Version bump to 1.10.1.1

* fixes removed eventColor_index fields when there is at least one DAVdroid
  account with enabled calendar colors and at least one account with disabled
  calendar colors

.gitlab-ci.yml

@@ -0,0 +1,31 @@
+image: registry.gitlab.com/bitfireat/davdroid:latest
+
+before_script:
+  - git submodule update --init --recursive
+  - export GRADLE_USER_HOME=`pwd`/.gradle; chmod +x gradlew
+
+cache:
+  paths:
+     - .gradle/
+     - apk/
+
+test:
+  script:
+    - (cd /sdk/emulator; ./emulator @test -no-audio -no-window & wait-for-emulator.sh)
+    - (mkdir -p apk && cd apk && wget -q https://f-droid.org/repo/org.dmfs.tasks_481.apk && adb install org.dmfs.tasks_481.apk)
+    - ./gradlew check mergeAndroidReports
+  artifacts:
+    paths:
+      - app/build/outputs/lint-results-debug.html
+      - app/build/reports
+      - build/reports
+
+pages:
+  script:
+    - ./gradlew app:dokka
+    - mkdir public && mv app/build/dokka public
+  artifacts:
+    paths:
+      - public
+  only:
+    - master-ose

.gitmodules

@@ -1,13 +1,12 @@
 [submodule "dav4android"]
 	path = dav4android
-	url = https://gitlab.com/bitfireAT/dav4android.git
+	url = ../dav4android.git
 [submodule "ical4android"]
 	path = ical4android
-	url = https://gitlab.com/bitfireAT/ical4android.git
+	url = ../ical4android.git
 [submodule "vcard4android"]
 	path = vcard4android
-	url = https://gitlab.com/bitfireAT/vcard4android.git
-[submodule "MemorizingTrustManager"]
-	path = MemorizingTrustManager
-	url = https://github.com/ge0rg/MemorizingTrustManager
-	ignore = dirty
+	url = ../vcard4android.git
+[submodule "cert4android"]
+	path = cert4android
+	url = ../cert4android.git

README.md

@@ -1,34 +1,40 @@
 
+[![build status](https://gitlab.com/bitfireAT/davdroid/badges/master-ose/build.svg)](https://gitlab.com/bitfireAT/davdroid/commits/master-ose)
+
+
 DAVdroid
 ========
 
-Please see the [DAVdroid Web site](https://davdroid.bitfire.at) for
+Please see the [DAVdroid Web site](https://www.davdroid.com) for
 comprehensive information about DAVdroid.
 
 DAVdroid is licensed under the [GPLv3 License](LICENSE).
 
-News and updates: [@davdroidapp](https://twitter.com/davdroidapp)
+News and updates: [@davdroidapp](https://twitter.com/davdroidapp) on Twitter
 
-Help and discussion: [DAVdroid forums](https://davdroid.bitfire.at/forums)
+Help and discussion: [DAVdroid forums](https://www.davdroid.com/forums/)
+
+**If you want to support DAVdroid, please consider [donating to DAVdroid](https://www.davdroid.com/donate/)
+or [purchasing it](https://www.davdroid.com/download/).**
+
+Generated KDoc: https://bitfireAT.gitlab.io/davdroid/dokka/app/
 
 Parts of DAVdroid have been outsourced into these libraries:
 
+* [cert4android](https://gitlab.com/bitfireAT/cert4android) – custom certificate management
 * [dav4android](https://gitlab.com/bitfireAT/dav4android) – WebDAV/CalDav/CardDAV framework
 * [ical4android](https://gitlab.com/bitfireAT/ical4android) – iCalendar processing and Calendar Provider access
 * [vcard4android](https://gitlab.com/bitfireAT/vcard4android) – VCard processing and Contacts Provider access
 
-[![Flattr this!](https://api.flattr.com/button/flattr-badge-large.png)](https://flattr.com/submit/auto?user_id=bitfire&url=https://davdroid.bitfire.at&title=DAVdroid&category=software)
-
 
 USED THIRD-PARTY LIBRARIES
 ==========================
 
 Those libraries are used by DAVdroid (alphabetically):
 
+* [Ambilwarna](https://github.com/yukuku/ambilwarna) – [Apache License, Version 2.0](https://github.com/yukuku/ambilwarna/blob/master/LICENSE)
 * [dnsjava](http://www.xbill.org/dnsjava/) – [BSD License](http://www.xbill.org/dnsjava/dnsjava-current/LICENSE)
-* [ez-vcard](https://code.google.com/p/ez-vcard/) – [New BSD License](http://opensource.org/licenses/BSD-3-Clause)
-* [iCal4j](http://ical4j.sourceforge.net/) – [New BSD License](http://sourceforge.net/p/ical4j/ical4j/ci/default/tree/LICENSE)
-* [MemorizingTrustManager](https://github.com/ge0rg/MemorizingTrustManager) – [MIT License](https://raw.githubusercontent.com/ge0rg/MemorizingTrustManager/master/LICENSE.txt)
-* [okhttp](https://square.github.io/okhttp/) – [Apache License, Version 2.0](https://square.github.io/okhttp/#license)
+* [ez-vcard](https://github.com/mangstadt/ez-vcard) – [New BSD License](http://opensource.org/licenses/BSD-3-Clause)
+* [iCal4j](https://github.com/ical4j/ical4j) – [New BSD License](http://sourceforge.net/p/ical4j/ical4j/ci/default/tree/LICENSE)
+* [okhttp](https://square.github.io/okhttp) – [Apache License, Version 2.0](https://square.github.io/okhttp/#license)
 * [Project Lombok](http://projectlombok.org/) – [MIT License](http://opensource.org/licenses/mit-license.php)
-* [SLF4J](http://www.slf4j.org/) – [MIT License](http://www.slf4j.org/license.html)

app/build.gradle

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2013 – 2016 Ricki Hirner (bitfire web engineering).
+ * Copyright (c) Ricki Hirner (bitfire web engineering).
  * All rights reserved. This program and the accompanying materials
  * are made available under the terms of the GNU Public License v3.0
  * which accompanies this distribution, and is available at
@@ -7,20 +7,37 @@
  */
 
 apply plugin: 'com.android.application'
+apply plugin: 'kotlin-android'
+apply plugin: 'kotlin-android-extensions'
+apply plugin: 'org.jetbrains.dokka-android'
 
 android {
-    compileSdkVersion 23
-    buildToolsVersion '23.0.2'
+    compileSdkVersion 27
+    buildToolsVersion '27.0.1'
 
     defaultConfig {
         applicationId "at.bitfire.davdroid"
-        minSdkVersion 14
-        targetSdkVersion 22
-
-        versionCode 88
-        versionName "1.0-beta1"
 
+        versionCode 205
         buildConfigField "long", "buildTime", System.currentTimeMillis() + "L"
+        buildConfigField "boolean", "customCerts", "true"
+
+        minSdkVersion 19        // Android 4.4
+        targetSdkVersion 27     // Android 8.1
+
+        // when using this, make sure that notification icons are real bitmaps
+        vectorDrawables.useSupportLibrary = true
+    }
+
+    flavorDimensions "type"
+
+    productFlavors {
+        standard {
+            versionName "1.10.1.1-ose"
+
+            buildConfigField "boolean", "customCerts", "true"
+            buildConfigField "boolean", "customCertsUI", "true"
+        }
     }
 
     buildTypes {
@@ -34,44 +51,58 @@ android {
     }
 
     lintOptions {
-        disable 'ExtraTranslation'
-        disable 'IconColors'
-        disable 'IconLauncherShape'
-        disable 'IconMissingDensityFolder'
-        disable 'InconsistentLayout'
-        disable 'MergeRootFrame'
-        disable 'MissingTranslation'
-        disable 'OldTargetApi'
+        disable 'GoogleAppIndexingWarning'      // we don't need Google indexing, thanks
+        disable 'ImpliedQuantity', 'MissingQuantity'		// quantities from Transifex may vary
+        disable 'MissingTranslation', 'ExtraTranslation'	// translations from Transifex are not always up to date
+        disable "OnClick"     // doesn't recognize Kotlin onClick methods
+        disable 'Recycle'           // doesn't understand Lombok's @Cleanup
         disable 'RtlEnabled'
+        disable 'RtlHardcoded'
         disable 'Typos'
     }
     packagingOptions {
-        exclude 'LICENSE'
-        exclude 'META-INF/LICENSE.txt'
-        exclude 'META-INF/NOTICE.txt'
+        exclude 'META-INF/DEPENDENCIES'
+        exclude 'META-INF/LICENSE'
+    }
+
+    defaultConfig {
+        testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"
     }
 }
 
-configurations.all {
-    exclude module: 'commons-logging'       // undocumented part of Android
-}
-
 dependencies {
-    provided 'org.projectlombok:lombok:1.16.6'
-
+    compile project(':cert4android')
     compile project(':dav4android')
     compile project(':ical4android')
     compile project(':vcard4android')
 
-    compile 'com.android.support:appcompat-v7:23.+'
-    compile 'com.android.support:cardview-v7:23.+'
-    compile 'com.android.support:design:23.+'
-    compile 'com.android.support:preference-v7:23.+'
+    compile "org.jetbrains.kotlin:kotlin-stdlib-jdk7:$kotlin_version"
+
+    compile 'com.android.support:appcompat-v7:27.0.2'
+    compile 'com.android.support:cardview-v7:27.0.2'
+    compile 'com.android.support:design:27.0.2'
+    compile 'com.android.support:preference-v14:27.0.2'
 
     compile 'com.github.yukuku:ambilwarna:2.0.1'
-    compile project(':MemorizingTrustManager')
 
-    androidTestCompile 'com.squareup.okhttp3:mockwebserver:3.2.0'
-    compile 'dnsjava:dnsjava:2.1.7'
-    compile 'org.apache.commons:commons-lang3:3.4'
+    compile 'com.squareup.okhttp3:logging-interceptor:3.9.1'
+    compile 'commons-io:commons-io:2.6'
+    compile 'dnsjava:dnsjava:2.1.8'
+    compile 'org.apache.commons:commons-lang3:3.6'
+    compile 'org.apache.commons:commons-collections4:4.1'
+
+    // for tests
+    //noinspection GradleDynamicVersion
+    androidTestCompile('com.android.support.test:runner:+') {
+        exclude group: 'com.android.support', module: 'support-annotations'
+    }
+    //noinspection GradleDynamicVersion
+    androidTestCompile('com.android.support.test:rules:+') {
+        exclude group: 'com.android.support', module: 'support-annotations'
+    }
+    androidTestCompile 'junit:junit:4.12'
+    androidTestCompile 'com.squareup.okhttp3:mockwebserver:3.9.1'
+
+    testCompile 'junit:junit:4.12'
+    testCompile 'com.squareup.okhttp3:mockwebserver:3.9.1'
 }

app/proguard-rules.txt

@@ -1,36 +1,43 @@
 
 # ProGuard usage for DAVdroid:
-# 	shrinking		yes - main reason for using ProGuard
-# 	optimization		no - too risky
-# 	obfuscation		no - DAVdroid is open-source
-# 	preverification		no (Android default)
+#       shrinking        yes (main reason for using ProGuard)
+#       optimization     yes
+#       obfuscation      no (DAVdroid is open-source)
+#       preverification  no
 
 -dontobfuscate
 
+-optimizations !code/simplification/arithmetic,!code/simplification/cast,!field/*,!class/merging/*
+-optimizationpasses 5
+-allowaccessmodification
+-dontpreverify
+
+# Kotlin
+-dontwarn kotlin.**
+
 # ez-vcard
--dontwarn com.fasterxml.jackson.**		# Jackson JSON Processor (for jCards) not used
--dontwarn freemarker.**				# freemarker templating library (for creating hCards) not used
--dontwarn org.jsoup.**				# jsoup library (for hCard parsing) not used
--dontwarn sun.misc.Perf
--keep class ezvcard.property.** { *; }		# keep all VCard properties (created at runtime)
+-dontwarn ezvcard.io.json.**            # JSON serializer (for jCards) not used
+-dontwarn freemarker.**                 # freemarker templating library (for creating hCards) not used
+-dontwarn org.jsoup.**                  # jsoup library (for hCard parsing) not used
+-keep class ezvcard.property.** { *; }  # keep all VCard properties (created at runtime)
 
 # ical4j: ignore unused dynamic libraries
 -dontwarn aQute.**
--dontwarn groovy.**				# Groovy-based ContentBuilder not used
+-dontwarn groovy.**                       # Groovy-based ContentBuilder not used
+-dontwarn javax.cache.**                  # no JCache support in Android
+-dontwarn net.fortuna.ical4j.model.**
 -dontwarn org.codehaus.groovy.**
--dontwarn org.apache.commons.logging.**		# Commons logging is not available
--dontwarn net.fortuna.ical4j.model.**		# ignore warnings from Groovy dependency
--keep class net.fortuna.ical4j.model.** { *; }	# keep all model classes (properties/factories, created at runtime)
+-dontwarn org.apache.log4j.**             # ignore warnings from log4j dependency
+-keep class net.fortuna.ical4j.** { *; }  # keep all model classes (properties/factories, created at runtime)
+-keep class org.threeten.bp.** { *; }     # keep ThreeTen (for time zone processing)
 
 # okhttp
--dontwarn java.nio.file.**		# not available on Android
--dontwarn org.codehaus.mojo.animal_sniffer.IgnoreJRERequirement
-
-# MemorizingTrustManager
--dontwarn de.duenndns.ssl.MemorizingTrustManager
+-dontwarn okio.**
+-dontwarn javax.annotation.Nullable
+-dontwarn javax.annotation.ParametersAreNonnullByDefault
 
 # dnsjava
--dontwarn sun.net.spi.nameservice.**		# not available on Android
+-dontwarn sun.net.spi.nameservice.**   # not available on Android
 
 # DAVdroid + libs
--keep class at.bitfire.** { *; }	# all DAVdroid code is required
+-keep class at.bitfire.** { *; }       # all DAVdroid code is required

app/src/androidTest/java/at/bitfire/davdroid/ArrayUtilsTest.java

@@ -1,39 +0,0 @@
-/*
- * Copyright © 2013 – 2015 Ricki Hirner (bitfire web engineering).
- * All rights reserved. This program and the accompanying materials
- * are made available under the terms of the GNU Public License v3.0
- * which accompanies this distribution, and is available at
- * http://www.gnu.org/licenses/gpl.html
- */
-package at.bitfire.davdroid;
-
-import junit.framework.TestCase;
-
-import java.util.Arrays;
-
-
-public class ArrayUtilsTest extends TestCase {
-	
-	public void testPartition() {
-		// n == 0
-		assertTrue(Arrays.deepEquals(
-				new Long[0][0],
-				ArrayUtils.partition(new Long[] { }, 5)));
-				
-		// n < max
-		assertTrue(Arrays.deepEquals(
-				new Long[][] { { 1l, 2l } },
-				ArrayUtils.partition(new Long[] { 1l, 2l }, 5)));
-		
-		// n == max
-		assertTrue(Arrays.deepEquals(
-				new Long[][] { { 1l, 2l }, { 3l, 4l } },
-				ArrayUtils.partition(new Long[] { 1l, 2l, 3l, 4l }, 2)));
-		
-		// n > max
-		assertTrue(Arrays.deepEquals(
-				new Long[][] { { 1l, 2l, 3l, 4l, 5l }, { 6l, 7l, 8l, 9l, 10l }, { 11l } },
-				ArrayUtils.partition(new Long[] { 1l, 2l, 3l, 4l, 5l, 6l, 7l, 8l, 9l, 10l, 11l }, 5)));
-	}
-	
-}

app/src/androidTest/java/at/bitfire/davdroid/CustomTlsSocketFactoryTest.kt

@@ -0,0 +1,128 @@
+/*
+ * Copyright © Ricki Hirner (bitfire web engineering).
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the GNU Public License v3.0
+ * which accompanies this distribution, and is available at
+ * http://www.gnu.org/licenses/gpl.html
+ */
+
+package at.bitfire.davdroid;
+
+import android.support.test.InstrumentationRegistry.getInstrumentation
+import at.bitfire.cert4android.CustomCertManager
+import okhttp3.OkHttpClient
+import okhttp3.Request
+import okhttp3.mockwebserver.MockWebServer
+import org.apache.commons.io.IOUtils
+import org.apache.commons.lang3.ArrayUtils.contains
+import org.junit.After
+import org.junit.Assert.*
+import org.junit.Before
+import org.junit.Test
+import java.net.Socket
+import java.security.KeyFactory
+import java.security.KeyStore
+import java.security.Principal
+import java.security.cert.CertificateFactory
+import java.security.cert.X509Certificate
+import java.security.spec.PKCS8EncodedKeySpec
+import javax.net.ssl.SSLSocket
+import javax.net.ssl.TrustManagerFactory
+import javax.net.ssl.X509ExtendedKeyManager
+import javax.net.ssl.X509TrustManager
+
+class CustomTlsSocketFactoryTest {
+
+    lateinit var certMgr: CustomCertManager
+    lateinit var factory: CustomTlsSocketFactory
+    val server = MockWebServer()
+
+    @Before
+    fun startServer() {
+        certMgr = CustomCertManager(getInstrumentation().context, false, true)
+        factory = CustomTlsSocketFactory(null, certMgr)
+        server.start()
+    }
+
+    @After
+    fun stopServer() {
+        server.shutdown()
+        certMgr.close()
+    }
+
+
+    @Test
+    fun testSendClientCertificate() {
+        var public: X509Certificate? = null
+        javaClass.classLoader.getResourceAsStream("sample.crt").use {
+            public = CertificateFactory.getInstance("X509").generateCertificate(it) as? X509Certificate
+        }
+        assertNotNull(public)
+
+        val keyFactory = KeyFactory.getInstance("RSA")
+        val private = keyFactory.generatePrivate(PKCS8EncodedKeySpec(readResource("sample.key")))
+        assertNotNull(private)
+
+        val keyStore = KeyStore.getInstance("AndroidKeyStore")
+        keyStore.load(null)
+        val alias = "sample"
+        keyStore.setKeyEntry(alias, private, null, arrayOf(public))
+        assertTrue(keyStore.containsAlias(alias))
+
+        val trustManagerFactory = TrustManagerFactory.getInstance("X509")
+        trustManagerFactory.init(null as KeyStore?)
+        val trustManager = trustManagerFactory.trustManagers.first() as X509TrustManager
+
+        val factory = CustomTlsSocketFactory(object: X509ExtendedKeyManager() {
+            override fun getServerAliases(p0: String?, p1: Array<out Principal>?): Array<String>? = null
+            override fun chooseServerAlias(p0: String?, p1: Array<out Principal>?, p2: Socket?) = null
+
+            override fun getClientAliases(p0: String?, p1: Array<out Principal>?) =
+                    arrayOf(alias)
+
+            override fun chooseClientAlias(p0: Array<out String>?, p1: Array<out Principal>?, p2: Socket?) =
+                    alias
+
+            override fun getCertificateChain(forAlias: String?) =
+                    arrayOf(public).takeIf { forAlias == alias }
+
+            override fun getPrivateKey(forAlias: String?) =
+                    private.takeIf { forAlias == alias }
+        }, trustManager)
+
+        /* known client cert test URLs (thanks!):
+        *  - https://prod.idrix.eu/secure/
+        *  - https://server.cryptomix.com/secure/
+        */
+        val client = OkHttpClient.Builder()
+                .sslSocketFactory(factory, trustManager)
+                .build()
+        client.newCall(Request.Builder()
+                .get()
+                .url("https://prod.idrix.eu/secure/")
+                .build()).execute().use { response ->
+            assertTrue(response.isSuccessful)
+            assertTrue(response.body()!!.string().contains("CN=User Cert,O=Internet Widgits Pty Ltd,ST=Some-State,C=CA"))
+        }
+    }
+
+    @Test
+    fun testUpgradeTLS() {
+        val s = factory.createSocket(server.hostName, server.port)
+        assertTrue(s is SSLSocket)
+        val ssl = s as SSLSocket
+
+        assertFalse(contains(ssl.enabledProtocols, "SSLv3"))
+        assertTrue(contains(ssl.enabledProtocols, "TLSv1"))
+        assertTrue(contains(ssl.enabledProtocols, "TLSv1.1"))
+        assertTrue(contains(ssl.enabledProtocols, "TLSv1.2"))
+    }
+
+
+    private fun readResource(name: String): ByteArray {
+        this.javaClass.classLoader.getResourceAsStream(name).use {
+            return IOUtils.toByteArray(it)
+        }
+    }
+
+}

app/src/androidTest/java/at/bitfire/davdroid/HttpClientTest.java

@@ -1,64 +0,0 @@
-/*
- * Copyright © 2013 – 2015 Ricki Hirner (bitfire web engineering).
- * All rights reserved. This program and the accompanying materials
- * are made available under the terms of the GNU Public License v3.0
- * which accompanies this distribution, and is available at
- * http://www.gnu.org/licenses/gpl.html
- */
-
-package at.bitfire.davdroid;
-
-import android.test.InstrumentationTestCase;
-
-import java.io.IOException;
-import java.net.URISyntaxException;
-
-import okhttp3.HttpUrl;
-import okhttp3.OkHttpClient;
-import okhttp3.Request;
-import okhttp3.mockwebserver.MockResponse;
-import okhttp3.mockwebserver.MockWebServer;
-
-public class HttpClientTest extends InstrumentationTestCase {
-
-    MockWebServer server;
-    OkHttpClient httpClient;
-
-    @Override
-    public void setUp() throws IOException {
-        httpClient = HttpClient.create(getInstrumentation().getTargetContext().getApplicationContext(), null);
-
-        server = new MockWebServer();
-        server.start();
-    }
-
-    @Override
-    public void tearDown() throws IOException {
-        server.shutdown();
-    }
-
-    public void testCookies() throws IOException, InterruptedException, URISyntaxException {
-        HttpUrl url = server.url("/");
-
-        // set cookie in first response
-        server.enqueue(new MockResponse()
-                .setResponseCode(200)
-                .setHeader("Set-Cookie", "theme=light; path=/")
-                .setBody("Cookie set"));
-        httpClient.newCall(new Request.Builder()
-                .get().url(url)
-                .build()).execute();
-        assertNull(server.takeRequest().getHeader("Cookie"));
-
-        // cookie should be sent with second request
-        server.enqueue(new MockResponse()
-                .setResponseCode(200));
-        httpClient.newCall(new Request.Builder()
-                .get().url(url)
-                .build()).execute();
-        //assertEquals("theme=light", server.takeRequest().getHeader("Cookie"));
-
-        // doesn't work for URLs with ports, see https://code.google.com/p/android/issues/detail?id=193475
-    }
-
-}

app/src/androidTest/java/at/bitfire/davdroid/SSLSocketFactoryCompatTest.java

@@ -1,56 +0,0 @@
-/*
- * Copyright © 2013 – 2015 Ricki Hirner (bitfire web engineering).
- * All rights reserved. This program and the accompanying materials
- * are made available under the terms of the GNU Public License v3.0
- * which accompanies this distribution, and is available at
- * http://www.gnu.org/licenses/gpl.html
- */
-
-package at.bitfire.davdroid;
-
-import android.os.Build;
-import android.test.InstrumentationTestCase;
-
-import junit.framework.TestCase;
-
-import java.io.IOException;
-import java.net.Socket;
-
-import javax.net.ssl.SSLSocket;
-
-import de.duenndns.ssl.MemorizingTrustManager;
-import okhttp3.OkHttpClient;
-import okhttp3.mockwebserver.MockWebServer;
-
-public class SSLSocketFactoryCompatTest extends InstrumentationTestCase {
-
-    SSLSocketFactoryCompat factory;
-    MockWebServer server = new MockWebServer();
-
-    @Override
-    protected void setUp() throws Exception {
-        factory = new SSLSocketFactoryCompat(new MemorizingTrustManager(getInstrumentation().getTargetContext().getApplicationContext()));
-        server.start();
-    }
-
-    @Override
-    protected void tearDown() throws Exception {
-        server.shutdown();
-    }
-
-
-    public void testUpgradeTLS() throws IOException {
-        Socket s = factory.createSocket(server.getHostName(), server.getPort());
-        assertTrue(s instanceof SSLSocket);
-
-        SSLSocket ssl = (SSLSocket)s;
-        assertFalse(org.apache.commons.lang3.ArrayUtils.contains(ssl.getEnabledProtocols(), "SSLv3"));
-        assertTrue(org.apache.commons.lang3.ArrayUtils.contains(ssl.getEnabledProtocols(), "TLSv1"));
-
-        if (Build.VERSION.SDK_INT >= 16) {
-            assertTrue(org.apache.commons.lang3.ArrayUtils.contains(ssl.getEnabledProtocols(), "TLSv1.1"));
-            assertTrue(org.apache.commons.lang3.ArrayUtils.contains(ssl.getEnabledProtocols(), "TLSv1.2"));
-        }
-    }
-
-}

app/src/androidTest/java/at/bitfire/davdroid/TestConstants.java

@@ -1,27 +0,0 @@
-/*
- * Copyright © 2013 – 2015 Ricki Hirner (bitfire web engineering).
- * All rights reserved. This program and the accompanying materials
- * are made available under the terms of the GNU Public License v3.0
- * which accompanies this distribution, and is available at
- * http://www.gnu.org/licenses/gpl.html
- */
-
-package at.bitfire.davdroid;
-
-import android.util.Log;
-
-import java.net.URI;
-import java.net.URISyntaxException;
-
-public class TestConstants {
-	public static final String ROBOHYDRA_BASE = "http://192.168.0.11:3000/";
-
-	public static URI roboHydra;
-	static {
-		try {
-			roboHydra = new URI(ROBOHYDRA_BASE);
-		} catch(URISyntaxException e) {
-			Log.wtf("davdroid.test.Constants", "Invalid RoboHydra base URL");
-		}
-	}
-}

app/src/androidTest/java/at/bitfire/davdroid/model/CollectionInfoTest.java

@@ -0,0 +1,133 @@
+/*
+ * Copyright © Ricki Hirner (bitfire web engineering).
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the GNU Public License v3.0
+ * which accompanies this distribution, and is available at
+ * http://www.gnu.org/licenses/gpl.html
+ */
+
+package at.bitfire.davdroid.model;
+
+import android.content.ContentValues;
+
+import org.junit.After;
+import org.junit.Before;
+import org.junit.Test;
+
+import java.io.IOException;
+
+import at.bitfire.dav4android.DavResource;
+import at.bitfire.dav4android.exception.DavException;
+import at.bitfire.dav4android.exception.HttpException;
+import at.bitfire.dav4android.property.ResourceType;
+import at.bitfire.davdroid.HttpClient;
+import at.bitfire.davdroid.model.ServiceDB.Collections;
+import okhttp3.mockwebserver.MockResponse;
+import okhttp3.mockwebserver.MockWebServer;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertFalse;
+import static org.junit.Assert.assertNull;
+import static org.junit.Assert.assertTrue;
+
+public class CollectionInfoTest {
+
+    HttpClient httpClient;
+    MockWebServer server = new MockWebServer();
+
+    @Before
+    public void setUp() {
+        httpClient = new HttpClient.Builder().build();
+    }
+
+    @After
+    public void shutDown() {
+        httpClient.close();
+    }
+
+
+    @Test
+    public void testFromDavResource() throws IOException, HttpException, DavException {
+        // r/w address book
+        server.enqueue(new MockResponse()
+                .setResponseCode(207)
+                .setBody("<multistatus xmlns='DAV:' xmlns:CARD='urn:ietf:params:xml:ns:carddav'>" +
+                        "<response>" +
+                        "   <href>/</href>" +
+                        "   <propstat><prop>" +
+                        "       <resourcetype><collection/><CARD:addressbook/></resourcetype>" +
+                        "       <displayname>My Contacts</displayname>" +
+                        "       <CARD:addressbook-description>My Contacts Description</CARD:addressbook-description>" +
+                        "   </prop></propstat>" +
+                        "</response>" +
+                        "</multistatus>"));
+
+        DavResource dav = new DavResource(httpClient.getOkHttpClient(), server.url("/"));
+        dav.propfind(0, ResourceType.NAME);
+        CollectionInfo info = new CollectionInfo(dav);
+        assertEquals(CollectionInfo.Type.ADDRESS_BOOK, info.getType());
+        assertFalse(info.getReadOnly());
+        assertEquals("My Contacts", info.getDisplayName());
+        assertEquals("My Contacts Description", info.getDescription());
+
+        // read-only calendar, no display name
+        server.enqueue(new MockResponse()
+                .setResponseCode(207)
+                .setBody("<multistatus xmlns='DAV:' xmlns:CAL='urn:ietf:params:xml:ns:caldav' xmlns:ICAL='http://apple.com/ns/ical/'>" +
+                        "<response>" +
+                        "   <href>/</href>" +
+                        "   <propstat><prop>" +
+                        "       <resourcetype><collection/><CAL:calendar/></resourcetype>" +
+                        "       <current-user-privilege-set><privilege><read/></privilege></current-user-privilege-set>" +
+                        "       <CAL:calendar-description>My Calendar</CAL:calendar-description>" +
+                        "       <CAL:calendar-timezone>tzdata</CAL:calendar-timezone>" +
+                        "       <ICAL:calendar-color>#ff0000</ICAL:calendar-color>" +
+                        "   </prop></propstat>" +
+                        "</response>" +
+                        "</multistatus>"));
+
+        dav = new DavResource(httpClient.getOkHttpClient(), server.url("/"));
+        dav.propfind(0, ResourceType.NAME);
+        info = new CollectionInfo(dav);
+        assertEquals(CollectionInfo.Type.CALENDAR, info.getType());
+        assertTrue(info.getReadOnly());
+        assertNull(info.getDisplayName());
+        assertEquals("My Calendar", info.getDescription());
+        assertEquals(0xFFFF0000, (int)info.getColor());
+        assertEquals("tzdata", info.getTimeZone());
+        assertTrue(info.getSupportsVEVENT());
+        assertTrue(info.getSupportsVTODO());
+    }
+
+    @Test
+    public void testFromDB() {
+        ContentValues values = new ContentValues();
+        values.put(Collections.ID, 1);
+        values.put(Collections.SERVICE_ID, 1);
+        values.put(Collections.TYPE, CollectionInfo.Type.CALENDAR.name());
+        values.put(Collections.URL, "http://example.com");
+        values.put(Collections.READ_ONLY, 1);
+        values.put(Collections.DISPLAY_NAME, "display name");
+        values.put(Collections.DESCRIPTION, "description");
+        values.put(Collections.COLOR, 0xFFFF0000);
+        values.put(Collections.TIME_ZONE, "tzdata");
+        values.put(Collections.SUPPORTS_VEVENT, 1);
+        values.put(Collections.SUPPORTS_VTODO, 1);
+        values.put(Collections.SYNC, 1);
+
+        CollectionInfo info = new CollectionInfo(values);
+        assertEquals(CollectionInfo.Type.CALENDAR, info.getType());
+        assertEquals(1, (long)info.getId());
+        assertEquals(1, (long)info.getServiceID());
+        assertEquals("http://example.com", info.getUrl());
+        assertTrue(info.getReadOnly());
+        assertEquals("display name", info.getDisplayName());
+        assertEquals("description", info.getDescription());
+        assertEquals(0xFFFF0000, (int)info.getColor());
+        assertEquals("tzdata", info.getTimeZone());
+        assertTrue(info.getSupportsVEVENT());
+        assertTrue(info.getSupportsVTODO());
+        assertTrue(info.getSelected());
+    }
+
+}

app/src/androidTest/java/at/bitfire/davdroid/resource/DavResourceFinderTest.java

@@ -1,90 +0,0 @@
-package at.bitfire.davdroid.resource;
-
-import android.test.InstrumentationTestCase;
-
-import java.io.IOException;
-import java.net.URI;
-
-import at.bitfire.dav4android.exception.DavException;
-import at.bitfire.dav4android.exception.HttpException;
-import at.bitfire.davdroid.ui.setup.DavResourceFinder;
-import at.bitfire.davdroid.ui.setup.LoginCredentials;
-import okhttp3.HttpUrl;
-import okhttp3.mockwebserver.MockResponse;
-import okhttp3.mockwebserver.MockWebServer;
-
-public class DavResourceFinderTest extends InstrumentationTestCase {
-
-    MockWebServer server = new MockWebServer();
-
-    @Override
-    protected void setUp() throws Exception {
-        server.start();
-    }
-
-    @Override
-    protected void tearDown() throws Exception {
-        server.shutdown();
-    }
-
-
-    public void testGetCurrentUserPrincipal() throws IOException, HttpException, DavException {
-        HttpUrl url = server.url("/dav");
-        LoginCredentials credentials = new LoginCredentials(url.uri(), "admin", "12345", true);
-        DavResourceFinder finder = new DavResourceFinder(getInstrumentation().getTargetContext().getApplicationContext(), credentials);
-
-        // positive test case
-        server.enqueue(new MockResponse()       // PROPFIND response
-                .setResponseCode(207)
-                .setHeader("Content-Type", "application/xml;charset=utf-8")
-                .setBody("<multistatus xmlns='DAV:'>" +
-                        "  <response>" +
-                        "    <href>/dav</href>" +
-                        "    <propstat>" +
-                        "      <prop>" +
-                        "        <current-user-principal><href>/principals/myself</href></current-user-principal>" +
-                        "      </prop>" +
-                        "      <status>HTTP/1.0 200 OK</status>" +
-                        "    </propstat>" +
-                        "  </response>" +
-                        "</multistatus>"));
-        server.enqueue(new MockResponse()       // OPTIONS response
-                .setResponseCode(200)
-                .setHeader("DAV", "addressbook"));
-        URI principal = finder.getCurrentUserPrincipal(url, DavResourceFinder.Service.CARDDAV);
-        assertEquals(url.resolve("/principals/myself").uri(), principal);
-
-        // negative test case: no current-user-principal
-        server.enqueue(new MockResponse()
-                .setResponseCode(207)
-                .setHeader("Content-Type", "application/xml;charset=utf-8")
-                .setBody("<multistatus xmlns='DAV:'>" +
-                        "  <response>" +
-                        "    <href>/dav</href>" +
-                      "      <status>HTTP/1.0 200 OK</status>" +
-                        "  </response>" +
-                        "</multistatus>"));
-        assertNull(finder.getCurrentUserPrincipal(url, DavResourceFinder.Service.CARDDAV));
-
-        // negative test case: requested service not available
-        server.enqueue(new MockResponse()       // PROPFIND response
-                .setResponseCode(207)
-                .setHeader("Content-Type", "application/xml;charset=utf-8")
-                .setBody("<multistatus xmlns='DAV:'>" +
-                        "  <response>" +
-                        "    <href>/dav</href>" +
-                        "    <propstat>" +
-                        "      <prop>" +
-                        "        <current-user-principal><href>/principals/myself</href></current-user-principal>" +
-                        "      </prop>" +
-                        "      <status>HTTP/1.0 200 OK</status>" +
-                        "    </propstat>" +
-                        "  </response>" +
-                        "</multistatus>"));
-        server.enqueue(new MockResponse()       // OPTIONS response
-                .setResponseCode(200)
-                .setHeader("DAV", "addressbook"));
-        assertNull(finder.getCurrentUserPrincipal(url, DavResourceFinder.Service.CALDAV));
-    }
-
-}

app/src/androidTest/java/at/bitfire/davdroid/settings/DefaultsProviderTest.kt

@@ -0,0 +1,39 @@
+/*
+ * Copyright © Ricki Hirner (bitfire web engineering).
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the GNU Public License v3.0
+ * which accompanies this distribution, and is available at
+ * http://www.gnu.org/licenses/gpl.html
+ */
+
+package at.bitfire.davdroid.settings
+
+import at.bitfire.davdroid.App
+import junit.framework.Assert.assertEquals
+import junit.framework.Assert.assertFalse
+import org.junit.Test
+
+class DefaultsProviderTest {
+
+    private val provider: Provider = DefaultsProvider()
+
+    @Test
+    fun testHas() {
+        assertEquals(Pair(false, true), provider.has("notExisting"))
+        assertEquals(Pair(true, true), provider.has(App.OVERRIDE_PROXY))
+    }
+
+    @Test
+    fun testGet() {
+        assertEquals(Pair("localhost", true), provider.getString(App.OVERRIDE_PROXY_HOST))
+        assertEquals(Pair(8118, true), provider.getInt(App.OVERRIDE_PROXY_PORT))
+    }
+
+    @Test
+    fun testPutRemove() {
+        assertEquals(Pair(false, true), provider.isWritable(App.OVERRIDE_PROXY))
+        assertFalse(provider.putBoolean(App.OVERRIDE_PROXY, true))
+        assertFalse(provider.remove(App.OVERRIDE_PROXY))
+    }
+
+}

app/src/androidTest/java/at/bitfire/davdroid/settings/SettingsTest.kt

@@ -0,0 +1,44 @@
+/*
+ * Copyright © Ricki Hirner (bitfire web engineering).
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the GNU Public License v3.0
+ * which accompanies this distribution, and is available at
+ * http://www.gnu.org/licenses/gpl.html
+ */
+
+package at.bitfire.davdroid.settings
+
+import android.content.ServiceConnection
+import android.support.test.InstrumentationRegistry
+import android.support.test.InstrumentationRegistry.getTargetContext
+import at.bitfire.davdroid.App
+import junit.framework.Assert.*
+import org.junit.After
+import org.junit.Before
+import org.junit.Test
+
+class SettingsTest {
+
+    lateinit var settings: Settings.Stub
+
+    @Before
+    fun init() {
+        InstrumentationRegistry.getContext().isRestricted
+        settings = Settings.getInstance(getTargetContext())!!
+    }
+
+    @After
+    fun shutdown() {
+        settings.close()
+    }
+
+
+    @Test
+    fun testHas() {
+        assertFalse(settings.has("notExisting"))
+
+        // provided by DefaultsProvider
+        assertTrue(settings.has(App.OVERRIDE_PROXY))
+    }
+
+}

app/src/androidTest/java/at/bitfire/davdroid/ui/setup/DavResourceFinderTest.java

@@ -0,0 +1,201 @@
+/*
+ * Copyright © Ricki Hirner (bitfire web engineering).
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the GNU Public License v3.0
+ * which accompanies this distribution, and is available at
+ * http://www.gnu.org/licenses/gpl.html
+ */
+
+package at.bitfire.davdroid.ui.setup;
+
+import org.junit.After;
+import org.junit.Before;
+import org.junit.Test;
+
+import java.io.IOException;
+import java.net.URI;
+
+import at.bitfire.dav4android.DavResource;
+import at.bitfire.dav4android.exception.DavException;
+import at.bitfire.dav4android.exception.HttpException;
+import at.bitfire.dav4android.property.AddressbookHomeSet;
+import at.bitfire.dav4android.property.ResourceType;
+import at.bitfire.davdroid.HttpClient;
+import at.bitfire.davdroid.log.Logger;
+import at.bitfire.davdroid.model.Credentials;
+import at.bitfire.davdroid.ui.setup.DavResourceFinder.Configuration.ServiceInfo;
+import okhttp3.mockwebserver.Dispatcher;
+import okhttp3.mockwebserver.MockResponse;
+import okhttp3.mockwebserver.MockWebServer;
+import okhttp3.mockwebserver.RecordedRequest;
+
+import static android.support.test.InstrumentationRegistry.getTargetContext;
+import static junit.framework.TestCase.assertFalse;
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertNull;
+import static org.junit.Assert.assertTrue;
+
+public class DavResourceFinderTest {
+
+    MockWebServer server = new MockWebServer();
+
+    DavResourceFinder finder;
+    HttpClient client;
+    LoginInfo loginInfo;
+
+    private static final String
+            PATH_NO_DAV = "/nodav",
+
+            PATH_CALDAV = "/caldav",
+            PATH_CARDDAV = "/carddav",
+            PATH_CALDAV_AND_CARDDAV = "/both-caldav-carddav",
+
+            SUBPATH_PRINCIPAL = "/principal",
+            SUBPATH_ADDRESSBOOK_HOMESET = "/addressbooks",
+            SUBPATH_ADDRESSBOOK = "/addressbooks/private-contacts";
+
+    @Before
+    public void initServerAndClient() throws Exception {
+        server.setDispatcher(new TestDispatcher());
+        server.start();
+
+        loginInfo = new LoginInfo(URI.create("/"), new Credentials("mock", "12345"));
+        finder = new DavResourceFinder(getTargetContext(), loginInfo);
+
+        client = new HttpClient.Builder()
+                .addAuthentication(null, loginInfo.credentials)
+                .build();
+    }
+
+    @After
+    public void stopServer() throws Exception {
+        server.shutdown();
+    }
+
+    @Test
+    public void testRememberIfAddressBookOrHomeset() throws IOException, HttpException, DavException {
+        ServiceInfo info;
+
+        // before dav.propfind(), no info is available
+        DavResource dav = new DavResource(client.getOkHttpClient(), server.url(PATH_CARDDAV + SUBPATH_PRINCIPAL));
+        finder.rememberIfAddressBookOrHomeset(dav, info = new ServiceInfo());
+        assertEquals(0, info.getCollections().size());
+        assertEquals(0, info.getHomeSets().size());
+
+        // recognize home set
+        dav.propfind(0, AddressbookHomeSet.NAME);
+        finder.rememberIfAddressBookOrHomeset(dav, info = new ServiceInfo());
+        assertEquals(0, info.getCollections().size());
+        assertEquals(1, info.getHomeSets().size());
+        assertEquals(server.url(PATH_CARDDAV + SUBPATH_ADDRESSBOOK_HOMESET + "/").uri(), info.getHomeSets().iterator().next());
+
+        // recognize address book
+        dav = new DavResource(client.getOkHttpClient(), server.url(PATH_CARDDAV + SUBPATH_ADDRESSBOOK));
+        dav.propfind(0, ResourceType.NAME);
+        finder.rememberIfAddressBookOrHomeset(dav, info = new ServiceInfo());
+        assertEquals(1, info.getCollections().size());
+        assertEquals(server.url(PATH_CARDDAV + SUBPATH_ADDRESSBOOK + "/").uri(), info.getCollections().keySet().iterator().next());
+        assertEquals(0, info.getHomeSets().size());
+    }
+
+    @Test
+    public void testProvidesService() throws IOException {
+        assertFalse(finder.providesService(server.url(PATH_NO_DAV), DavResourceFinder.Service.CALDAV));
+        assertFalse(finder.providesService(server.url(PATH_NO_DAV), DavResourceFinder.Service.CARDDAV));
+
+        assertTrue(finder.providesService(server.url(PATH_CALDAV), DavResourceFinder.Service.CALDAV));
+        assertFalse(finder.providesService(server.url(PATH_CALDAV), DavResourceFinder.Service.CARDDAV));
+
+        assertTrue(finder.providesService(server.url(PATH_CARDDAV), DavResourceFinder.Service.CARDDAV));
+        assertFalse(finder.providesService(server.url(PATH_CARDDAV), DavResourceFinder.Service.CALDAV));
+
+        assertTrue(finder.providesService(server.url(PATH_CALDAV_AND_CARDDAV), DavResourceFinder.Service.CALDAV));
+        assertTrue(finder.providesService(server.url(PATH_CALDAV_AND_CARDDAV), DavResourceFinder.Service.CARDDAV));
+    }
+
+    @Test
+    public void testGetCurrentUserPrincipal() throws IOException, HttpException, DavException {
+        assertNull(finder.getCurrentUserPrincipal(server.url(PATH_NO_DAV), DavResourceFinder.Service.CALDAV));
+        assertNull(finder.getCurrentUserPrincipal(server.url(PATH_NO_DAV), DavResourceFinder.Service.CARDDAV));
+
+        assertEquals(
+                server.url(PATH_CALDAV + SUBPATH_PRINCIPAL).uri(),
+                finder.getCurrentUserPrincipal(server.url(PATH_CALDAV), DavResourceFinder.Service.CALDAV)
+        );
+        assertNull(finder.getCurrentUserPrincipal(server.url(PATH_CALDAV), DavResourceFinder.Service.CARDDAV));
+
+        assertEquals(
+                server.url(PATH_CARDDAV + SUBPATH_PRINCIPAL).uri(),
+                finder.getCurrentUserPrincipal(server.url(PATH_CARDDAV), DavResourceFinder.Service.CARDDAV)
+        );
+        assertNull(finder.getCurrentUserPrincipal(server.url(PATH_CARDDAV), DavResourceFinder.Service.CALDAV));
+    }
+
+
+    // mock server
+
+    public class TestDispatcher extends Dispatcher {
+
+        @Override
+        public MockResponse dispatch(RecordedRequest rq) throws InterruptedException {
+            if (!checkAuth(rq)) {
+                MockResponse authenticate = new MockResponse().setResponseCode(401);
+                authenticate.setHeader("WWW-Authenticate", "Basic realm=\"test\"");
+                return authenticate;
+            }
+
+            String path = rq.getPath();
+
+            if ("OPTIONS".equalsIgnoreCase(rq.getMethod())) {
+                String dav = null;
+                if (path.startsWith(PATH_CALDAV))
+                    dav = "calendar-access";
+                else if (path.startsWith(PATH_CARDDAV))
+                    dav = "addressbook";
+                else if (path.startsWith(PATH_CALDAV_AND_CARDDAV))
+                    dav = "calendar-access, addressbook";
+                MockResponse response = new MockResponse().setResponseCode(200);
+                if (dav != null)
+                       response.addHeader("DAV", dav);
+                return response;
+
+            } else if ("PROPFIND".equalsIgnoreCase(rq.getMethod())) {
+                String props = null;
+                switch (path) {
+                    case PATH_CALDAV:
+                    case PATH_CARDDAV:
+                        props = "<current-user-principal><href>" + path + SUBPATH_PRINCIPAL + "</href></current-user-principal>";
+                        break;
+
+                    case PATH_CARDDAV + SUBPATH_PRINCIPAL:
+                        props = "<CARD:addressbook-home-set>" +
+                                "   <href>" + PATH_CARDDAV + SUBPATH_ADDRESSBOOK_HOMESET + "</href>" +
+                                "</CARD:addressbook-home-set>";
+                        break;
+                    case PATH_CARDDAV + SUBPATH_ADDRESSBOOK:
+                        props = "<resourcetype>" +
+                                "   <collection/>" +
+                                "   <CARD:addressbook/>" +
+                                "</resourcetype>";
+                        break;
+                }
+                Logger.log.info("Sending props: " + props);
+                return new MockResponse()
+                        .setResponseCode(207)
+                        .setBody("<multistatus xmlns='DAV:' xmlns:CARD='urn:ietf:params:xml:ns:carddav'>" +
+                                "<response>" +
+                                "   <href>" + rq.getPath() + "</href>" +
+                                "   <propstat><prop>" + props + "</prop></propstat>" +
+                                "</response>" +
+                                "</multistatus>");
+            }
+
+            return new MockResponse().setResponseCode(404);
+        }
+
+        private boolean checkAuth(RecordedRequest rq) {
+            return "Basic bW9jazoxMjM0NQ==".equals(rq.getHeader("Authorization"));
+        }
+    }
+
+}

app/src/androidTest/resources/sample.crt

@@ -0,0 +1,24 @@
+-----BEGIN CERTIFICATE-----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+-----END CERTIFICATE-----

app/src/main/AndroidManifest.xml

@@ -12,33 +12,32 @@
           android:installLocation="internalOnly">
 
     <!-- normal permissions -->
+    <uses-permission android:name="android.permission.ACCESS_NETWORK_STATE"/>
+    <uses-permission android:name="android.permission.ACCESS_WIFI_STATE"/>
     <uses-permission android:name="android.permission.INTERNET"/>
-    <uses-permission android:name="android.permission.GET_ACCOUNTS"/>
-    <uses-permission android:name="android.permission.MANAGE_ACCOUNTS"/>
     <uses-permission android:name="android.permission.READ_SYNC_SETTINGS"/>
+    <uses-permission android:name="android.permission.READ_SYNC_STATS"/>
     <uses-permission android:name="android.permission.WRITE_SYNC_SETTINGS"/>
+    <uses-permission android:name="android.permission.REQUEST_IGNORE_BATTERY_OPTIMIZATIONS"/>
+
+    <!-- account management permissions not required for own accounts since API level 22 -->
+    <uses-permission android:name="android.permission.AUTHENTICATE_ACCOUNTS" android:maxSdkVersion="22"/>
+    <uses-permission android:name="android.permission.GET_ACCOUNTS" android:maxSdkVersion="22"/>
+    <uses-permission android:name="android.permission.MANAGE_ACCOUNTS" android:maxSdkVersion="22"/>
 
-    <!-- legacy permissions -->
     <!--
          for writing external log files; permission only required for SDK <= 18 because since then,
          writing to app-private directory doesn't require extra permissions
     -->
-    <uses-permission
-        android:name="android.permission.READ_EXTERNAL_STORAGE"
-        android:maxSdkVersion="18"
-        tools:ignore="UnusedAttribute"/>
-    <uses-permission
-        android:name="android.permission.WRITE_EXTERNAL_STORAGE"
-        android:maxSdkVersion="18"
-        tools:ignore="UnusedAttribute"/>
+    <uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" android:maxSdkVersion="18"/>
+    <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" android:maxSdkVersion="18"/>
 
     <!-- other permissions -->
-    <uses-permission android:name="android.permission.AUTHENTICATE_ACCOUNTS"/>
-    <uses-permission android:name="android.permission.READ_CONTACTS"/>
     <!-- android.permission-group.CONTACTS -->
+    <uses-permission android:name="android.permission.READ_CONTACTS"/>
     <uses-permission android:name="android.permission.WRITE_CONTACTS"/>
-    <uses-permission android:name="android.permission.READ_CALENDAR"/>
     <!-- android.permission-group.CALENDAR -->
+    <uses-permission android:name="android.permission.READ_CALENDAR"/>
     <uses-permission android:name="android.permission.WRITE_CALENDAR"/>
 
     <!-- ical4android declares task access permissions -->
@@ -47,10 +46,76 @@
         android:name=".App"
         android:allowBackup="true"
         android:fullBackupContent="false"
-        android:icon="@drawable/ic_launcher"
+        android:networkSecurityConfig="@xml/network_security_config"
+        android:icon="@mipmap/ic_launcher"
         android:label="@string/app_name"
         android:theme="@style/AppTheme"
         tools:ignore="UnusedAttribute">
+
+        <service android:name=".DavService"/>
+        <service android:name=".settings.Settings"/>
+
+        <activity
+            android:name=".ui.AccountsActivity"
+            android:label="@string/app_name"
+            android:theme="@style/AppTheme.NoActionBar">
+            <intent-filter>
+                <action android:name="android.intent.action.MAIN"/>
+                <category android:name="android.intent.category.LAUNCHER"/>
+            </intent-filter>
+        </activity>
+
+        <activity
+            android:name=".ui.AboutActivity"
+            android:label="@string/app_name"
+            android:theme="@style/AppTheme.NoActionBar"
+            android:parentActivityName=".ui.AccountsActivity"/>
+
+        <activity
+            android:name=".ui.AppSettingsActivity"
+            android:label="@string/app_settings"
+            android:parentActivityName=".ui.AccountsActivity"/>
+
+        <activity android:name=".ui.PermissionsActivity"
+                  android:label="@string/permissions_title"
+                  android:parentActivityName=".ui.AccountsActivity"/>
+
+        <activity
+            android:name=".ui.setup.LoginActivity"
+            android:label="@string/login_title"
+            android:parentActivityName=".ui.AccountsActivity">
+            <intent-filter>
+                <action android:name="android.intent.action.MAIN"/>
+            </intent-filter>
+        </activity>
+
+        <activity
+            android:name=".ui.AccountActivity"
+            android:parentActivityName=".ui.AccountsActivity">
+        </activity>
+        <activity android:name=".ui.AccountSettingsActivity"/>
+        <activity android:name=".ui.CreateAddressBookActivity"
+            android:label="@string/create_addressbook"/>
+        <activity android:name=".ui.CreateCalendarActivity"
+                  android:label="@string/create_calendar"/>
+
+        <activity
+            android:name=".ui.DebugInfoActivity"
+            android:parentActivityName=".ui.AppSettingsActivity"
+            android:exported="true"
+            android:label="@string/debug_info_title">
+        </activity>
+        <provider
+            android:name="android.support.v4.content.FileProvider"
+            android:authorities="@string/authority_log_provider"
+            android:grantUriPermissions="true"
+            android:exported="false">
+            <meta-data
+                android:name="android.support.FILE_PROVIDER_PATHS"
+                android:resource="@xml/log_paths" />
+        </provider>
+
+        <!-- account type "DAVdroid" -->
         <service
             android:name=".syncadapter.AccountAuthenticatorService"
             android:exported="false">
@@ -62,22 +127,6 @@
                 android:name="android.accounts.AccountAuthenticator"
                 android:resource="@xml/account_authenticator"/>
         </service>
-        <service
-            android:name=".syncadapter.ContactsSyncAdapterService"
-            android:exported="true"
-            android:process=":sync"
-            tools:ignore="ExportedService">
-            <intent-filter>
-                <action android:name="android.content.SyncAdapter"/>
-            </intent-filter>
-
-            <meta-data
-                android:name="android.content.SyncAdapter"
-                android:resource="@xml/sync_contacts"/>
-            <meta-data
-                android:name="android.provider.CONTACTS_STRUCTURE"
-                android:resource="@xml/contacts"/>
-        </service>
         <service
             android:name=".syncadapter.CalendarsSyncAdapterService"
             android:exported="true"
@@ -104,63 +153,54 @@
                 android:name="android.content.SyncAdapter"
                 android:resource="@xml/sync_tasks"/>
         </service>
+
+        <!-- account type "DAVdroid Address book" -->
         <service
-            android:name=".DavService"
-            android:enabled="true">
+            android:name=".syncadapter.NullAuthenticatorService"
+            android:exported="false">
+            <intent-filter>
+                <action android:name="android.accounts.AccountAuthenticator"/>
+            </intent-filter>
+
+            <meta-data
+                android:name="android.accounts.AccountAuthenticator"
+                android:resource="@xml/account_authenticator_address_book"/>
         </service>
-        <receiver
-            android:name=".AccountsChangedReceiver"
-            android:enabled="true"
-            android:exported="true">
-            <intent-filter>
-                <action android:name="android.accounts.LOGIN_ACCOUNTS_CHANGED"/>
-            </intent-filter>
-        </receiver>
-
-        <activity
-            android:name=".ui.AccountsActivity"
-            android:label="@string/app_name"
-            android:theme="@style/AppTheme.NoActionBar">
-            <intent-filter>
-                <action android:name="android.intent.action.MAIN"/>
-                <category android:name="android.intent.category.LAUNCHER"/>
-            </intent-filter>
-        </activity>
-
-        <activity
-            android:name=".ui.AppSettingsActivity"
-            android:label="@string/app_settings"
-            android:parentActivityName=".ui.AccountsActivity"/>
-
-        <activity
-            android:name=".ui.setup.LoginActivity"
-            android:label="@string/login_title"
-            android:parentActivityName=".ui.AccountsActivity">
-            <intent-filter>
-                <action android:name="android.intent.action.MAIN"/>
-            </intent-filter>
-        </activity>
-
-        <activity
-            android:name=".ui.AccountActivity"
-            android:parentActivityName=".ui.AccountsActivity">
-        </activity>
-        <activity android:name=".ui.AccountSettingsActivity"/>
-        <activity android:name=".ui.CreateAddressBookActivity"
-            android:label="@string/create_addressbook"/>
-        <activity android:name=".ui.CreateCalendarActivity"
-                  android:label="@string/create_calendar"/>
-
-        <activity
-            android:name=".ui.DebugInfoActivity"
+        <provider
+            android:authorities="@string/address_books_authority"
+            android:exported="false"
+            android:label="@string/address_books_authority_title"
+            android:name=".syncadapter.AddressBookProvider"
+            android:multiprocess="false"/>
+        <service
+            android:name=".syncadapter.AddressBooksSyncAdapterService"
             android:exported="true"
-            android:label="@string/debug_info_title">
-        </activity>
+            android:process=":sync"
+            tools:ignore="ExportedService">
+            <intent-filter>
+                <action android:name="android.content.SyncAdapter"/>
+            </intent-filter>
 
-        <!-- MemorizingTrustManager -->
-        <activity
-            android:name="de.duenndns.ssl.MemorizingActivity"
-            android:theme="@android:style/Theme.Holo.Light.Dialog.NoActionBar"/>
+            <meta-data
+                android:name="android.content.SyncAdapter"
+                android:resource="@xml/sync_address_books"/>
+        </service>
+        <service
+            android:name=".syncadapter.ContactsSyncAdapterService"
+            android:exported="true"
+            android:process=":sync"
+            tools:ignore="ExportedService">
+            <intent-filter>
+                <action android:name="android.content.SyncAdapter"/>
+            </intent-filter>
+
+            <meta-data
+                android:name="android.content.SyncAdapter"
+                android:resource="@xml/sync_contacts"/>
+            <meta-data
+                android:name="android.provider.CONTACTS_STRUCTURE"
+                android:resource="@xml/contacts"/>
+        </service>
 
     </application>
 

app/src/main/aidl/at/bitfire/davdroid/settings/ISettings.aidl

@@ -0,0 +1,28 @@
+package at.bitfire.davdroid.settings;
+
+import at.bitfire.davdroid.settings.ISettingsObserver;
+
+interface ISettings {
+
+    void forceReload();
+
+    boolean has(String key);
+
+    boolean getBoolean(String key, boolean defaultValue);
+    int getInt(String key, int defaultValue);
+    long getLong(String key, long defaultValue);
+    String getString(String key, String defaultValue);
+
+    boolean isWritable(String key);
+
+    boolean putBoolean(String key, boolean value);
+    boolean putInt(String key, int value);
+    boolean putLong(String key, long value);
+    boolean putString(String key, String value);
+
+    boolean remove(String key);
+
+    void registerObserver(ISettingsObserver observer);
+    void unregisterObserver(ISettingsObserver observer);
+
+}

app/src/main/aidl/at/bitfire/davdroid/settings/ISettingsObserver.aidl

@@ -0,0 +1,7 @@
+package at.bitfire.davdroid.settings;
+
+interface ISettingsObserver {
+
+    void onSettingsChanged();
+
+}

app/src/main/assets/apache2.html

@@ -0,0 +1,153 @@
+<h3>Apache License, Version 2.0, January 2004</h3>
+<p><a href="http://www.apache.org/licenses/">http://www.apache.org/licenses/</a> </p>
+<p>TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION</p>
+<p><strong><a name="definitions">1. Definitions</a></strong>.</p>
+<p>"License" shall mean the terms and conditions for use, reproduction, and
+distribution as defined by Sections 1 through 9 of this document.</p>
+<p>"Licensor" shall mean the copyright owner or entity authorized by the
+copyright owner that is granting the License.</p>
+<p>"Legal Entity" shall mean the union of the acting entity and all other
+entities that control, are controlled by, or are under common control with
+that entity. For the purposes of this definition, "control" means (i) the
+power, direct or indirect, to cause the direction or management of such
+entity, whether by contract or otherwise, or (ii) ownership of fifty
+percent (50%) or more of the outstanding shares, or (iii) beneficial
+ownership of such entity.</p>
+<p>"You" (or "Your") shall mean an individual or Legal Entity exercising
+permissions granted by this License.</p>
+<p>"Source" form shall mean the preferred form for making modifications,
+including but not limited to software source code, documentation source,
+and configuration files.</p>
+<p>"Object" form shall mean any form resulting from mechanical transformation
+or translation of a Source form, including but not limited to compiled
+object code, generated documentation, and conversions to other media types.</p>
+<p>"Work" shall mean the work of authorship, whether in Source or Object form,
+made available under the License, as indicated by a copyright notice that
+is included in or attached to the work (an example is provided in the
+Appendix below).</p>
+<p>"Derivative Works" shall mean any work, whether in Source or Object form,
+that is based on (or derived from) the Work and for which the editorial
+revisions, annotations, elaborations, or other modifications represent, as
+a whole, an original work of authorship. For the purposes of this License,
+Derivative Works shall not include works that remain separable from, or
+merely link (or bind by name) to the interfaces of, the Work and Derivative
+Works thereof.</p>
+<p>"Contribution" shall mean any work of authorship, including the original
+version of the Work and any modifications or additions to that Work or
+Derivative Works thereof, that is intentionally submitted to Licensor for
+inclusion in the Work by the copyright owner or by an individual or Legal
+Entity authorized to submit on behalf of the copyright owner. For the
+purposes of this definition, "submitted" means any form of electronic,
+verbal, or written communication sent to the Licensor or its
+representatives, including but not limited to communication on electronic
+mailing lists, source code control systems, and issue tracking systems that
+are managed by, or on behalf of, the Licensor for the purpose of discussing
+and improving the Work, but excluding communication that is conspicuously
+marked or otherwise designated in writing by the copyright owner as "Not a
+Contribution."</p>
+<p>"Contributor" shall mean Licensor and any individual or Legal Entity on
+behalf of whom a Contribution has been received by Licensor and
+subsequently incorporated within the Work.</p>
+<p><strong><a name="copyright">2. Grant of Copyright License</a></strong>. Subject to the
+terms and conditions of this License, each Contributor hereby grants to You
+a perpetual, worldwide, non-exclusive, no-charge, royalty-free, irrevocable
+copyright license to reproduce, prepare Derivative Works of, publicly
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+<p><strong><a name="patent">3. Grant of Patent License</a></strong>. Subject to the terms
+and conditions of this License, each Contributor hereby grants to You a
+perpetual, worldwide, non-exclusive, no-charge, royalty-free, irrevocable
+(except as stated in this section) patent license to make, have made, use,
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+granted to You under this License for that Work shall terminate as of the
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+You meet the following conditions:</p>
+
+<p>a. You must give any other recipients of the Work or Derivative Works a
+copy of this License; and</p>
+
+<p>b. You must cause any modified files to carry prominent notices stating
+that You changed the files; and</p>
+
+<p>c. You must retain, in the Source form of any Derivative Works that You
+distribute, all copyright, patent, trademark, and attribution notices from
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+
+<p>d. If the Work includes a "NOTICE" text file as part of its distribution,
+then any Derivative Works that You distribute must include a readable copy
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+appear. The contents of the NOTICE file are for informational purposes only
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+within Derivative Works that You distribute, alongside or as an addendum to
+the NOTICE text from the Work, provided that such additional attribution
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+<br/>
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+You may add Your own copyright statement to Your modifications and may
+provide additional or different license terms and conditions for use,
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+
+<p><strong><a name="contributions">5. Submission of Contributions</a></strong>. Unless You
+explicitly state otherwise, any Contribution intentionally submitted for
+inclusion in the Work by You to the Licensor shall be under the terms and
+conditions of this License, without any additional terms or conditions.
+Notwithstanding the above, nothing herein shall supersede or modify the
+terms of any separate license agreement you may have executed with Licensor
+regarding such Contributions.</p>
+<p><strong><a name="trademarks">6. Trademarks</a></strong>. This License does not grant
+permission to use the trade names, trademarks, service marks, or product
+names of the Licensor, except as required for reasonable and customary use
+in describing the origin of the Work and reproducing the content of the
+NOTICE file.</p>
+<p><strong><a name="no-warranty">7. Disclaimer of Warranty</a></strong>. Unless required by
+applicable law or agreed to in writing, Licensor provides the Work (and
+each Contributor provides its Contributions) on an "AS IS" BASIS, WITHOUT
+WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied, including,
+without limitation, any warranties or conditions of TITLE,
+NON-INFRINGEMENT, MERCHANTABILITY, or FITNESS FOR A PARTICULAR PURPOSE. You
+are solely responsible for determining the appropriateness of using or
+redistributing the Work and assume any risks associated with Your exercise
+of permissions under this License.</p>
+<p><strong><a name="no-liability">8. Limitation of Liability</a></strong>. In no event and
+under no legal theory, whether in tort (including negligence), contract, or
+otherwise, unless required by applicable law (such as deliberate and
+grossly negligent acts) or agreed to in writing, shall any Contributor be
+liable to You for damages, including any direct, indirect, special,
+incidental, or consequential damages of any character arising as a result
+of this License or out of the use or inability to use the Work (including
+but not limited to damages for loss of goodwill, work stoppage, computer
+failure or malfunction, or any and all other commercial damages or losses),
+even if such Contributor has been advised of the possibility of such
+damages.</p>
+<p><strong><a name="additional">9. Accepting Warranty or Additional Liability</a></strong>.
+While redistributing the Work or Derivative Works thereof, You may choose
+to offer, and charge a fee for, acceptance of support, warranty, indemnity,
+or other liability obligations and/or rights consistent with this License.
+However, in accepting such obligations, You may act only on Your own behalf
+and on Your sole responsibility, not on behalf of any other Contributor,
+and only if You agree to indemnify, defend, and hold each Contributor
+harmless for any liability incurred by, or claims asserted against, such
+Contributor by reason of your accepting any such warranty or additional
+liability.</p>
+
+<p>END OF TERMS AND CONDITIONS</p>

app/src/main/assets/bsd-3clause.html

@@ -0,0 +1,28 @@
+<h3>BSD License (3-clause)</h3>
+
+<p>Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions
+are met:</p>
+
+<p>o Redistributions of source code must retain the above copyright
+notice, this list of conditions and the following disclaimer.</p>
+
+<p>o Redistributions in binary form must reproduce the above copyright
+notice, this list of conditions and the following disclaimer in the
+documentation and/or other materials provided with the distribution.</p>
+
+<p>o Neither the name of Ben Fortuna nor the names of any other contributors
+may be used to endorse or promote products derived from this software
+without specific prior written permission.</p>
+
+<p>THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE COPYRIGHT OWNER OR
+CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
+PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
+LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.</p>

app/src/main/assets/bsd.html

@@ -0,0 +1,23 @@
+<h3>BSD License</h3>
+
+<p>Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are met:</p>
+
+<p>1. Redistributions of source code must retain the above copyright notice, this
+   list of conditions and the following disclaimer.</p>
+
+<p>2. Redistributions in binary form must reproduce the above copyright notice,
+   this list of conditions and the following disclaimer in the documentation
+   and/or other materials provided with the distribution.</p>
+
+<p>THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
+ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
+ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+(INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.</p>
+

app/src/main/assets/gpl-3.0-standalone.html

@@ -0,0 +1,628 @@
+<h3 style="text-align: center;">GNU GENERAL PUBLIC LICENSE</h3>
+<p style="text-align: center;">Version 3, 29 June 2007</p>
+
+<p>Copyright &copy; 2007 Free Software Foundation, Inc.
+ &lt;<a href="http://fsf.org/">http://fsf.org/</a>&gt;</p><p>
+ Everyone is permitted to copy and distribute verbatim copies
+ of this license document, but changing it is not allowed.</p>
+
+<h3><a name="preamble"></a>Preamble</h3>
+
+<p>The GNU General Public License is a free, copyleft license for
+software and other kinds of works.</p>
+
+<p>The licenses for most software and other practical works are designed
+to take away your freedom to share and change the works.  By contrast,
+the GNU General Public License is intended to guarantee your freedom to
+share and change all versions of a program--to make sure it remains free
+software for all its users.  We, the Free Software Foundation, use the
+GNU General Public License for most of our software; it applies also to
+any other work released this way by its authors.  You can apply it to
+your programs, too.</p>
+
+<p>When we speak of free software, we are referring to freedom, not
+price.  Our General Public Licenses are designed to make sure that you
+have the freedom to distribute copies of free software (and charge for
+them if you wish), that you receive source code or can get it if you
+want it, that you can change the software or use pieces of it in new
+free programs, and that you know you can do these things.</p>
+
+<p>To protect your rights, we need to prevent others from denying you
+these rights or asking you to surrender the rights.  Therefore, you have
+certain responsibilities if you distribute copies of the software, or if
+you modify it: responsibilities to respect the freedom of others.</p>
+
+<p>For example, if you distribute copies of such a program, whether
+gratis or for a fee, you must pass on to the recipients the same
+freedoms that you received.  You must make sure that they, too, receive
+or can get the source code.  And you must show them these terms so they
+know their rights.</p>
+
+<p>Developers that use the GNU GPL protect your rights with two steps:
+(1) assert copyright on the software, and (2) offer you this License
+giving you legal permission to copy, distribute and/or modify it.</p>
+
+<p>For the developers' and authors' protection, the GPL clearly explains
+that there is no warranty for this free software.  For both users' and
+authors' sake, the GPL requires that modified versions be marked as
+changed, so that their problems will not be attributed erroneously to
+authors of previous versions.</p>
+
+<p>Some devices are designed to deny users access to install or run
+modified versions of the software inside them, although the manufacturer
+can do so.  This is fundamentally incompatible with the aim of
+protecting users' freedom to change the software.  The systematic
+pattern of such abuse occurs in the area of products for individuals to
+use, which is precisely where it is most unacceptable.  Therefore, we
+have designed this version of the GPL to prohibit the practice for those
+products.  If such problems arise substantially in other domains, we
+stand ready to extend this provision to those domains in future versions
+of the GPL, as needed to protect the freedom of users.</p>
+
+<p>Finally, every program is threatened constantly by software patents.
+States should not allow patents to restrict development and use of
+software on general-purpose computers, but in those that do, we wish to
+avoid the special danger that patents applied to a free program could
+make it effectively proprietary.  To prevent this, the GPL assures that
+patents cannot be used to render the program non-free.</p>
+
+<p>The precise terms and conditions for copying, distribution and
+modification follow.</p>
+
+<h3><a name="terms"></a>TERMS AND CONDITIONS</h3>
+
+<h4><a name="section0"></a>0. Definitions.</h4>
+
+<p>&ldquo;This License&rdquo; refers to version 3 of the GNU General Public License.</p>
+
+<p>&ldquo;Copyright&rdquo; also means copyright-like laws that apply to other kinds of
+works, such as semiconductor masks.</p>
+ 
+<p>&ldquo;The Program&rdquo; refers to any copyrightable work licensed under this
+License.  Each licensee is addressed as &ldquo;you&rdquo;.  &ldquo;Licensees&rdquo; and
+&ldquo;recipients&rdquo; may be individuals or organizations.</p>
+
+<p>To &ldquo;modify&rdquo; a work means to copy from or adapt all or part of the work
+in a fashion requiring copyright permission, other than the making of an
+exact copy.  The resulting work is called a &ldquo;modified version&rdquo; of the
+earlier work or a work &ldquo;based on&rdquo; the earlier work.</p>
+
+<p>A &ldquo;covered work&rdquo; means either the unmodified Program or a work based
+on the Program.</p>
+
+<p>To &ldquo;propagate&rdquo; a work means to do anything with it that, without
+permission, would make you directly or secondarily liable for
+infringement under applicable copyright law, except executing it on a
+computer or modifying a private copy.  Propagation includes copying,
+distribution (with or without modification), making available to the
+public, and in some countries other activities as well.</p>
+
+<p>To &ldquo;convey&rdquo; a work means any kind of propagation that enables other
+parties to make or receive copies.  Mere interaction with a user through
+a computer network, with no transfer of a copy, is not conveying.</p>
+
+<p>An interactive user interface displays &ldquo;Appropriate Legal Notices&rdquo;
+to the extent that it includes a convenient and prominently visible
+feature that (1) displays an appropriate copyright notice, and (2)
+tells the user that there is no warranty for the work (except to the
+extent that warranties are provided), that licensees may convey the
+work under this License, and how to view a copy of this License.  If
+the interface presents a list of user commands or options, such as a
+menu, a prominent item in the list meets this criterion.</p>
+
+<h4><a name="section1"></a>1. Source Code.</h4>
+
+<p>The &ldquo;source code&rdquo; for a work means the preferred form of the work
+for making modifications to it.  &ldquo;Object code&rdquo; means any non-source
+form of a work.</p>
+
+<p>A &ldquo;Standard Interface&rdquo; means an interface that either is an official
+standard defined by a recognized standards body, or, in the case of
+interfaces specified for a particular programming language, one that
+is widely used among developers working in that language.</p>
+
+<p>The &ldquo;System Libraries&rdquo; of an executable work include anything, other
+than the work as a whole, that (a) is included in the normal form of
+packaging a Major Component, but which is not part of that Major
+Component, and (b) serves only to enable use of the work with that
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+implementation is available to the public in source code form.  A
+&ldquo;Major Component&rdquo;, in this context, means a major essential component
+(kernel, window system, and so on) of the specific operating system
+(if any) on which the executable work runs, or a compiler used to
+produce the work, or an object code interpreter used to run it.</p>
+
+<p>The &ldquo;Corresponding Source&rdquo; for a work in object code form means all
+the source code needed to generate, install, and (for an executable
+work) run the object code and to modify the work, including scripts to
+control those activities.  However, it does not include the work's
+System Libraries, or general-purpose tools or generally available free
+programs which are used unmodified in performing those activities but
+which are not part of the work.  For example, Corresponding Source
+includes interface definition files associated with source files for
+the work, and the source code for shared libraries and dynamically
+linked subprograms that the work is specifically designed to require,
+such as by intimate data communication or control flow between those
+subprograms and other parts of the work.</p>
+
+<p>The Corresponding Source need not include anything that users
+can regenerate automatically from other parts of the Corresponding
+Source.</p>
+
+<p>The Corresponding Source for a work in source code form is that
+same work.</p>
+
+<h4><a name="section2"></a>2. Basic Permissions.</h4>
+
+<p>All rights granted under this License are granted for the term of
+copyright on the Program, and are irrevocable provided the stated
+conditions are met.  This License explicitly affirms your unlimited
+permission to run the unmodified Program.  The output from running a
+covered work is covered by this License only if the output, given its
+content, constitutes a covered work.  This License acknowledges your
+rights of fair use or other equivalent, as provided by copyright law.</p>
+
+<p>You may make, run and propagate covered works that you do not
+convey, without conditions so long as your license otherwise remains
+in force.  You may convey covered works to others for the sole purpose
+of having them make modifications exclusively for you, or provide you
+with facilities for running those works, provided that you comply with
+the terms of this License in conveying all material for which you do
+not control copyright.  Those thus making or running the covered works
+for you must do so exclusively on your behalf, under your direction
+and control, on terms that prohibit them from making any copies of
+your copyrighted material outside their relationship with you.</p>
+
+<p>Conveying under any other circumstances is permitted solely under
+the conditions stated below.  Sublicensing is not allowed; section 10
+makes it unnecessary.</p>
+
+<h4><a name="section3"></a>3. Protecting Users' Legal Rights From Anti-Circumvention Law.</h4>
+
+<p>No covered work shall be deemed part of an effective technological
+measure under any applicable law fulfilling obligations under article
+11 of the WIPO copyright treaty adopted on 20 December 1996, or
+similar laws prohibiting or restricting circumvention of such
+measures.</p>
+
+<p>When you convey a covered work, you waive any legal power to forbid
+circumvention of technological measures to the extent such circumvention
+is effected by exercising rights under this License with respect to
+the covered work, and you disclaim any intention to limit operation or
+modification of the work as a means of enforcing, against the work's
+users, your or third parties' legal rights to forbid circumvention of
+technological measures.</p>
+
+<h4><a name="section4"></a>4. Conveying Verbatim Copies.</h4>
+
+<p>You may convey verbatim copies of the Program's source code as you
+receive it, in any medium, provided that you conspicuously and
+appropriately publish on each copy an appropriate copyright notice;
+keep intact all notices stating that this License and any
+non-permissive terms added in accord with section 7 apply to the code;
+keep intact all notices of the absence of any warranty; and give all
+recipients a copy of this License along with the Program.</p>
+
+<p>You may charge any price or no price for each copy that you convey,
+and you may offer support or warranty protection for a fee.</p>
+
+<h4><a name="section5"></a>5. Conveying Modified Source Versions.</h4>
+
+<p>You may convey a work based on the Program, or the modifications to
+produce it from the Program, in the form of source code under the
+terms of section 4, provided that you also meet all of these conditions:</p>
+
+<ul>
+<li>a) The work must carry prominent notices stating that you modified
+    it, and giving a relevant date.</li>
+
+<li>b) The work must carry prominent notices stating that it is
+    released under this License and any conditions added under section
+    7.  This requirement modifies the requirement in section 4 to
+    &ldquo;keep intact all notices&rdquo;.</li>
+
+<li>c) You must license the entire work, as a whole, under this
+    License to anyone who comes into possession of a copy.  This
+    License will therefore apply, along with any applicable section 7
+    additional terms, to the whole of the work, and all its parts,
+    regardless of how they are packaged.  This License gives no
+    permission to license the work in any other way, but it does not
+    invalidate such permission if you have separately received it.</li>
+
+<li>d) If the work has interactive user interfaces, each must display
+    Appropriate Legal Notices; however, if the Program has interactive
+    interfaces that do not display Appropriate Legal Notices, your
+    work need not make them do so.</li>
+</ul>
+
+<p>A compilation of a covered work with other separate and independent
+works, which are not by their nature extensions of the covered work,
+and which are not combined with it such as to form a larger program,
+in or on a volume of a storage or distribution medium, is called an
+&ldquo;aggregate&rdquo; if the compilation and its resulting copyright are not
+used to limit the access or legal rights of the compilation's users
+beyond what the individual works permit.  Inclusion of a covered work
+in an aggregate does not cause this License to apply to the other
+parts of the aggregate.</p>
+
+<h4><a name="section6"></a>6. Conveying Non-Source Forms.</h4>
+
+<p>You may convey a covered work in object code form under the terms
+of sections 4 and 5, provided that you also convey the
+machine-readable Corresponding Source under the terms of this License,
+in one of these ways:</p>
+
+<ul>
+<li>a) Convey the object code in, or embodied in, a physical product
+    (including a physical distribution medium), accompanied by the
+    Corresponding Source fixed on a durable physical medium
+    customarily used for software interchange.</li>
+
+<li>b) Convey the object code in, or embodied in, a physical product
+    (including a physical distribution medium), accompanied by a
+    written offer, valid for at least three years and valid for as
+    long as you offer spare parts or customer support for that product
+    model, to give anyone who possesses the object code either (1) a
+    copy of the Corresponding Source for all the software in the
+    product that is covered by this License, on a durable physical
+    medium customarily used for software interchange, for a price no
+    more than your reasonable cost of physically performing this
+    conveying of source, or (2) access to copy the
+    Corresponding Source from a network server at no charge.</li>
+
+<li>c) Convey individual copies of the object code with a copy of the
+    written offer to provide the Corresponding Source.  This
+    alternative is allowed only occasionally and noncommercially, and
+    only if you received the object code with such an offer, in accord
+    with subsection 6b.</li>
+
+<li>d) Convey the object code by offering access from a designated
+    place (gratis or for a charge), and offer equivalent access to the
+    Corresponding Source in the same way through the same place at no
+    further charge.  You need not require recipients to copy the
+    Corresponding Source along with the object code.  If the place to
+    copy the object code is a network server, the Corresponding Source
+    may be on a different server (operated by you or a third party)
+    that supports equivalent copying facilities, provided you maintain
+    clear directions next to the object code saying where to find the
+    Corresponding Source.  Regardless of what server hosts the
+    Corresponding Source, you remain obligated to ensure that it is
+    available for as long as needed to satisfy these requirements.</li>
+
+<li>e) Convey the object code using peer-to-peer transmission, provided
+    you inform other peers where the object code and Corresponding
+    Source of the work are being offered to the general public at no
+    charge under subsection 6d.</li>
+</ul>
+
+<p>A separable portion of the object code, whose source code is excluded
+from the Corresponding Source as a System Library, need not be
+included in conveying the object code work.</p>
+
+<p>A &ldquo;User Product&rdquo; is either (1) a &ldquo;consumer product&rdquo;, which means any
+tangible personal property which is normally used for personal, family,
+or household purposes, or (2) anything designed or sold for incorporation
+into a dwelling.  In determining whether a product is a consumer product,
+doubtful cases shall be resolved in favor of coverage.  For a particular
+product received by a particular user, &ldquo;normally used&rdquo; refers to a
+typical or common use of that class of product, regardless of the status
+of the particular user or of the way in which the particular user
+actually uses, or expects or is expected to use, the product.  A product
+is a consumer product regardless of whether the product has substantial
+commercial, industrial or non-consumer uses, unless such uses represent
+the only significant mode of use of the product.</p>
+
+<p>&ldquo;Installation Information&rdquo; for a User Product means any methods,
+procedures, authorization keys, or other information required to install
+and execute modified versions of a covered work in that User Product from
+a modified version of its Corresponding Source.  The information must
+suffice to ensure that the continued functioning of the modified object
+code is in no case prevented or interfered with solely because
+modification has been made.</p>
+
+<p>If you convey an object code work under this section in, or with, or
+specifically for use in, a User Product, and the conveying occurs as
+part of a transaction in which the right of possession and use of the
+User Product is transferred to the recipient in perpetuity or for a
+fixed term (regardless of how the transaction is characterized), the
+Corresponding Source conveyed under this section must be accompanied
+by the Installation Information.  But this requirement does not apply
+if neither you nor any third party retains the ability to install
+modified object code on the User Product (for example, the work has
+been installed in ROM).</p>
+
+<p>The requirement to provide Installation Information does not include a
+requirement to continue to provide support service, warranty, or updates
+for a work that has been modified or installed by the recipient, or for
+the User Product in which it has been modified or installed.  Access to a
+network may be denied when the modification itself materially and
+adversely affects the operation of the network or violates the rules and
+protocols for communication across the network.</p>
+
+<p>Corresponding Source conveyed, and Installation Information provided,
+in accord with this section must be in a format that is publicly
+documented (and with an implementation available to the public in
+source code form), and must require no special password or key for
+unpacking, reading or copying.</p>
+
+<h4><a name="section7"></a>7. Additional Terms.</h4>
+
+<p>&ldquo;Additional permissions&rdquo; are terms that supplement the terms of this
+License by making exceptions from one or more of its conditions.
+Additional permissions that are applicable to the entire Program shall
+be treated as though they were included in this License, to the extent
+that they are valid under applicable law.  If additional permissions
+apply only to part of the Program, that part may be used separately
+under those permissions, but the entire Program remains governed by
+this License without regard to the additional permissions.</p>
+
+<p>When you convey a copy of a covered work, you may at your option
+remove any additional permissions from that copy, or from any part of
+it.  (Additional permissions may be written to require their own
+removal in certain cases when you modify the work.)  You may place
+additional permissions on material, added by you to a covered work,
+for which you have or can give appropriate copyright permission.</p>
+
+<p>Notwithstanding any other provision of this License, for material you
+add to a covered work, you may (if authorized by the copyright holders of
+that material) supplement the terms of this License with terms:</p>
+
+<ul>
+<li>a) Disclaiming warranty or limiting liability differently from the
+    terms of sections 15 and 16 of this License; or</li>
+
+<li>b) Requiring preservation of specified reasonable legal notices or
+    author attributions in that material or in the Appropriate Legal
+    Notices displayed by works containing it; or</li>
+
+<li>c) Prohibiting misrepresentation of the origin of that material, or
+    requiring that modified versions of such material be marked in
+    reasonable ways as different from the original version; or</li>
+
+<li>d) Limiting the use for publicity purposes of names of licensors or
+    authors of the material; or</li>
+
+<li>e) Declining to grant rights under trademark law for use of some
+    trade names, trademarks, or service marks; or</li>
+
+<li>f) Requiring indemnification of licensors and authors of that
+    material by anyone who conveys the material (or modified versions of
+    it) with contractual assumptions of liability to the recipient, for
+    any liability that these contractual assumptions directly impose on
+    those licensors and authors.</li>
+</ul>
+
+<p>All other non-permissive additional terms are considered &ldquo;further
+restrictions&rdquo; within the meaning of section 10.  If the Program as you
+received it, or any part of it, contains a notice stating that it is
+governed by this License along with a term that is a further
+restriction, you may remove that term.  If a license document contains
+a further restriction but permits relicensing or conveying under this
+License, you may add to a covered work material governed by the terms
+of that license document, provided that the further restriction does
+not survive such relicensing or conveying.</p>
+
+<p>If you add terms to a covered work in accord with this section, you
+must place, in the relevant source files, a statement of the
+additional terms that apply to those files, or a notice indicating
+where to find the applicable terms.</p>
+
+<p>Additional terms, permissive or non-permissive, may be stated in the
+form of a separately written license, or stated as exceptions;
+the above requirements apply either way.</p>
+
+<h4><a name="section8"></a>8. Termination.</h4>
+
+<p>You may not propagate or modify a covered work except as expressly
+provided under this License.  Any attempt otherwise to propagate or
+modify it is void, and will automatically terminate your rights under
+this License (including any patent licenses granted under the third
+paragraph of section 11).</p>
+
+<p>However, if you cease all violation of this License, then your
+license from a particular copyright holder is reinstated (a)
+provisionally, unless and until the copyright holder explicitly and
+finally terminates your license, and (b) permanently, if the copyright
+holder fails to notify you of the violation by some reasonable means
+prior to 60 days after the cessation.</p>
+
+<p>Moreover, your license from a particular copyright holder is
+reinstated permanently if the copyright holder notifies you of the
+violation by some reasonable means, this is the first time you have
+received notice of violation of this License (for any work) from that
+copyright holder, and you cure the violation prior to 30 days after
+your receipt of the notice.</p>
+
+<p>Termination of your rights under this section does not terminate the
+licenses of parties who have received copies or rights from you under
+this License.  If your rights have been terminated and not permanently
+reinstated, you do not qualify to receive new licenses for the same
+material under section 10.</p>
+
+<h4><a name="section9"></a>9. Acceptance Not Required for Having Copies.</h4>
+
+<p>You are not required to accept this License in order to receive or
+run a copy of the Program.  Ancillary propagation of a covered work
+occurring solely as a consequence of using peer-to-peer transmission
+to receive a copy likewise does not require acceptance.  However,
+nothing other than this License grants you permission to propagate or
+modify any covered work.  These actions infringe copyright if you do
+not accept this License.  Therefore, by modifying or propagating a
+covered work, you indicate your acceptance of this License to do so.</p>
+
+<h4><a name="section10"></a>10. Automatic Licensing of Downstream Recipients.</h4>
+
+<p>Each time you convey a covered work, the recipient automatically
+receives a license from the original licensors, to run, modify and
+propagate that work, subject to this License.  You are not responsible
+for enforcing compliance by third parties with this License.</p>
+
+<p>An &ldquo;entity transaction&rdquo; is a transaction transferring control of an
+organization, or substantially all assets of one, or subdividing an
+organization, or merging organizations.  If propagation of a covered
+work results from an entity transaction, each party to that
+transaction who receives a copy of the work also receives whatever
+licenses to the work the party's predecessor in interest had or could
+give under the previous paragraph, plus a right to possession of the
+Corresponding Source of the work from the predecessor in interest, if
+the predecessor has it or can get it with reasonable efforts.</p>
+
+<p>You may not impose any further restrictions on the exercise of the
+rights granted or affirmed under this License.  For example, you may
+not impose a license fee, royalty, or other charge for exercise of
+rights granted under this License, and you may not initiate litigation
+(including a cross-claim or counterclaim in a lawsuit) alleging that
+any patent claim is infringed by making, using, selling, offering for
+sale, or importing the Program or any portion of it.</p>
+
+<h4><a name="section11"></a>11. Patents.</h4>
+
+<p>A &ldquo;contributor&rdquo; is a copyright holder who authorizes use under this
+License of the Program or a work on which the Program is based.  The
+work thus licensed is called the contributor's &ldquo;contributor version&rdquo;.</p>
+
+<p>A contributor's &ldquo;essential patent claims&rdquo; are all patent claims
+owned or controlled by the contributor, whether already acquired or
+hereafter acquired, that would be infringed by some manner, permitted
+by this License, of making, using, or selling its contributor version,
+but do not include claims that would be infringed only as a
+consequence of further modification of the contributor version.  For
+purposes of this definition, &ldquo;control&rdquo; includes the right to grant
+patent sublicenses in a manner consistent with the requirements of
+this License.</p>
+
+<p>Each contributor grants you a non-exclusive, worldwide, royalty-free
+patent license under the contributor's essential patent claims, to
+make, use, sell, offer for sale, import and otherwise run, modify and
+propagate the contents of its contributor version.</p>
+
+<p>In the following three paragraphs, a &ldquo;patent license&rdquo; is any express
+agreement or commitment, however denominated, not to enforce a patent
+(such as an express permission to practice a patent or covenant not to
+sue for patent infringement).  To &ldquo;grant&rdquo; such a patent license to a
+party means to make such an agreement or commitment not to enforce a
+patent against the party.</p>
+
+<p>If you convey a covered work, knowingly relying on a patent license,
+and the Corresponding Source of the work is not available for anyone
+to copy, free of charge and under the terms of this License, through a
+publicly available network server or other readily accessible means,
+then you must either (1) cause the Corresponding Source to be so
+available, or (2) arrange to deprive yourself of the benefit of the
+patent license for this particular work, or (3) arrange, in a manner
+consistent with the requirements of this License, to extend the patent
+license to downstream recipients.  &ldquo;Knowingly relying&rdquo; means you have
+actual knowledge that, but for the patent license, your conveying the
+covered work in a country, or your recipient's use of the covered work
+in a country, would infringe one or more identifiable patents in that
+country that you have reason to believe are valid.</p>
+  
+<p>If, pursuant to or in connection with a single transaction or
+arrangement, you convey, or propagate by procuring conveyance of, a
+covered work, and grant a patent license to some of the parties
+receiving the covered work authorizing them to use, propagate, modify
+or convey a specific copy of the covered work, then the patent license
+you grant is automatically extended to all recipients of the covered
+work and works based on it.</p>
+
+<p>A patent license is &ldquo;discriminatory&rdquo; if it does not include within
+the scope of its coverage, prohibits the exercise of, or is
+conditioned on the non-exercise of one or more of the rights that are
+specifically granted under this License.  You may not convey a covered
+work if you are a party to an arrangement with a third party that is
+in the business of distributing software, under which you make payment
+to the third party based on the extent of your activity of conveying
+the work, and under which the third party grants, to any of the
+parties who would receive the covered work from you, a discriminatory
+patent license (a) in connection with copies of the covered work
+conveyed by you (or copies made from those copies), or (b) primarily
+for and in connection with specific products or compilations that
+contain the covered work, unless you entered into that arrangement,
+or that patent license was granted, prior to 28 March 2007.</p>
+
+<p>Nothing in this License shall be construed as excluding or limiting
+any implied license or other defenses to infringement that may
+otherwise be available to you under applicable patent law.</p>
+
+<h4><a name="section12"></a>12. No Surrender of Others' Freedom.</h4>
+
+<p>If conditions are imposed on you (whether by court order, agreement or
+otherwise) that contradict the conditions of this License, they do not
+excuse you from the conditions of this License.  If you cannot convey a
+covered work so as to satisfy simultaneously your obligations under this
+License and any other pertinent obligations, then as a consequence you may
+not convey it at all.  For example, if you agree to terms that obligate you
+to collect a royalty for further conveying from those to whom you convey
+the Program, the only way you could satisfy both those terms and this
+License would be to refrain entirely from conveying the Program.</p>
+
+<h4><a name="section13"></a>13. Use with the GNU Affero General Public License.</h4>
+
+<p>Notwithstanding any other provision of this License, you have
+permission to link or combine any covered work with a work licensed
+under version 3 of the GNU Affero General Public License into a single
+combined work, and to convey the resulting work.  The terms of this
+License will continue to apply to the part which is the covered work,
+but the special requirements of the GNU Affero General Public License,
+section 13, concerning interaction through a network will apply to the
+combination as such.</p>
+
+<h4><a name="section14"></a>14. Revised Versions of this License.</h4>
+
+<p>The Free Software Foundation may publish revised and/or new versions of
+the GNU General Public License from time to time.  Such new versions will
+be similar in spirit to the present version, but may differ in detail to
+address new problems or concerns.</p>
+
+<p>Each version is given a distinguishing version number.  If the
+Program specifies that a certain numbered version of the GNU General
+Public License &ldquo;or any later version&rdquo; applies to it, you have the
+option of following the terms and conditions either of that numbered
+version or of any later version published by the Free Software
+Foundation.  If the Program does not specify a version number of the
+GNU General Public License, you may choose any version ever published
+by the Free Software Foundation.</p>
+
+<p>If the Program specifies that a proxy can decide which future
+versions of the GNU General Public License can be used, that proxy's
+public statement of acceptance of a version permanently authorizes you
+to choose that version for the Program.</p>
+
+<p>Later license versions may give you additional or different
+permissions.  However, no additional obligations are imposed on any
+author or copyright holder as a result of your choosing to follow a
+later version.</p>
+
+<h4><a name="section15"></a>15. Disclaimer of Warranty.</h4>
+
+<p>THERE IS NO WARRANTY FOR THE PROGRAM, TO THE EXTENT PERMITTED BY
+APPLICABLE LAW.  EXCEPT WHEN OTHERWISE STATED IN WRITING THE COPYRIGHT
+HOLDERS AND/OR OTHER PARTIES PROVIDE THE PROGRAM &ldquo;AS IS&rdquo; WITHOUT WARRANTY
+OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED TO,
+THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+PURPOSE.  THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF THE PROGRAM
+IS WITH YOU.  SHOULD THE PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF
+ALL NECESSARY SERVICING, REPAIR OR CORRECTION.</p>
+
+<h4><a name="section16"></a>16. Limitation of Liability.</h4>
+
+<p>IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING
+WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MODIFIES AND/OR CONVEYS
+THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES, INCLUDING ANY
+GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE
+USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED TO LOSS OF
+DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD
+PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER PROGRAMS),
+EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF
+SUCH DAMAGES.</p>
+
+<h4><a name="section17"></a>17. Interpretation of Sections 15 and 16.</h4>
+
+<p>If the disclaimer of warranty and limitation of liability provided
+above cannot be given local legal effect according to their terms,
+reviewing courts shall apply local law that most closely approximates
+an absolute waiver of all civil liability in connection with the
+Program, unless a warranty or assumption of liability accompanies a
+copy of the Program in return for a fee.</p>
+
+<p>END OF TERMS AND CONDITIONS</p>

app/src/main/assets/mit.html

@@ -0,0 +1,7 @@
+<h3>The MIT License (MIT)</h3>
+
+<p>Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:</p>
+
+<p>The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.</p>
+
+<p>THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.</p>

app/src/main/java/at/bitfire/davdroid/AccountSettings.java

@@ -1,387 +0,0 @@
-/*
- * Copyright © 2013 – 2015 Ricki Hirner (bitfire web engineering).
- * All rights reserved. This program and the accompanying materials
- * are made available under the terms of the GNU Public License v3.0
- * which accompanies this distribution, and is available at
- * http://www.gnu.org/licenses/gpl.html
- */
-package at.bitfire.davdroid;
-
-import android.accounts.Account;
-import android.accounts.AccountManager;
-import android.app.Notification;
-import android.app.NotificationManager;
-import android.content.ContentProviderClient;
-import android.content.ContentResolver;
-import android.content.ContentUris;
-import android.content.ContentValues;
-import android.content.Context;
-import android.content.Intent;
-import android.content.PeriodicSync;
-import android.database.Cursor;
-import android.database.sqlite.SQLiteDatabase;
-import android.graphics.drawable.BitmapDrawable;
-import android.net.Uri;
-import android.os.Bundle;
-import android.provider.CalendarContract;
-import android.provider.CalendarContract.Calendars;
-import android.provider.ContactsContract;
-import android.support.annotation.NonNull;
-import android.support.v7.app.NotificationCompat;
-import android.text.TextUtils;
-
-import java.lang.reflect.Method;
-import java.net.URI;
-import java.net.URISyntaxException;
-import java.util.HashSet;
-import java.util.List;
-import java.util.Set;
-import java.util.logging.Level;
-
-import at.bitfire.davdroid.model.ServiceDB;
-import at.bitfire.davdroid.model.ServiceDB.*;
-import at.bitfire.davdroid.resource.LocalAddressBook;
-import at.bitfire.davdroid.resource.LocalCalendar;
-import at.bitfire.davdroid.resource.LocalTaskList;
-import at.bitfire.ical4android.CalendarStorageException;
-import at.bitfire.ical4android.TaskProvider;
-import at.bitfire.vcard4android.ContactsStorageException;
-import lombok.Cleanup;
-import okhttp3.HttpUrl;
-
-public class AccountSettings {
-	private final static int CURRENT_VERSION = 3;
-	private final static String
-		KEY_SETTINGS_VERSION = "version",
-
-        KEY_USERNAME = "user_name",
-		KEY_AUTH_PREEMPTIVE = "auth_preemptive";
-
-    /** Time range limitation to the past [in days]
-        value = null              default value (DEFAULT_TIME_RANGE_PAST_DAYS)
-                < 0 (-1)          no limit
-                >= 0              entries more than n days in the past won't be synchronized
-     */
-    private final static String KEY_TIME_RANGE_PAST_DAYS = "time_range_past_days";
-    private final static int DEFAULT_TIME_RANGE_PAST_DAYS = 90;
-
-	public final static long SYNC_INTERVAL_MANUALLY = -1;
-
-	final Context context;
-	final AccountManager accountManager;
-	final Account account;
-	
-	
-    public AccountSettings(@NonNull Context context, @NonNull Account account) {
-		this.context = context;
-		this.account = account;
-		
-		accountManager = AccountManager.get(context);
-		
-		synchronized(AccountSettings.class) {
-			int version = 0;
-			try {
-				version = Integer.parseInt(accountManager.getUserData(account, KEY_SETTINGS_VERSION));
-			} catch(NumberFormatException ignored) {
-			}
-            App.log.info("Account " + account.name + " has version " + version + ", current version: " + CURRENT_VERSION);
-
-			if (version < CURRENT_VERSION) {
-                Notification notify = new NotificationCompat.Builder(context)
-                        .setSmallIcon(R.drawable.ic_new_releases_light)
-                        .setLargeIcon(((BitmapDrawable)context.getResources().getDrawable(R.drawable.ic_launcher)).getBitmap())
-                        .setContentTitle(context.getString(R.string.settings_version_update))
-                        .setContentText(context.getString(R.string.settings_version_update_settings_updated))
-                        .setSubText(context.getString(R.string.settings_version_update_install_hint))
-                        .setCategory(NotificationCompat.CATEGORY_SYSTEM)
-                        .setPriority(NotificationCompat.PRIORITY_HIGH)
-                        .setLocalOnly(true)
-                        .build();
-                NotificationManager nm = (NotificationManager)context.getSystemService(Context.NOTIFICATION_SERVICE);
-                nm.notify(Constants.NOTIFICATION_ACCOUNT_SETTINGS_UPDATED, notify);
-
-                update(version);
-            }
-		}
-	}
-
-	public static Bundle initialUserData(String userName, boolean preemptive) {
-		Bundle bundle = new Bundle();
-		bundle.putString(KEY_SETTINGS_VERSION, String.valueOf(CURRENT_VERSION));
-		bundle.putString(KEY_USERNAME, userName);
-		bundle.putString(KEY_AUTH_PREEMPTIVE, Boolean.toString(preemptive));
-		return bundle;
-	}
-	
-	
-	// authentication settings
-
-	public String username() { return accountManager.getUserData(account, KEY_USERNAME); }
-	public void username(@NonNull String userName) { accountManager.setUserData(account, KEY_USERNAME, userName); }
-	
-	public String password() { return accountManager.getPassword(account); }
-	public void password(@NonNull String password) { accountManager.setPassword(account, password); }
-	
-	public boolean preemptiveAuth() { return Boolean.parseBoolean(accountManager.getUserData(account, KEY_AUTH_PREEMPTIVE)); }
-	public void preemptiveAuth(boolean preemptive) { accountManager.setUserData(account, KEY_AUTH_PREEMPTIVE, Boolean.toString(preemptive)); }
-
-
-	// sync. settings
-
-	public Long getSyncInterval(@NonNull String authority) {
-		if (ContentResolver.getIsSyncable(account, authority) <= 0)
-			return null;
-
-		if (ContentResolver.getSyncAutomatically(account, authority)) {
-			List<PeriodicSync> syncs = ContentResolver.getPeriodicSyncs(account, authority);
-			if (syncs.isEmpty())
-				return SYNC_INTERVAL_MANUALLY;
-			else
-				return syncs.get(0).period;
-		} else
-			return SYNC_INTERVAL_MANUALLY;
-	}
-
-	public void setSyncInterval(@NonNull String authority, long seconds) {
-		if (seconds == SYNC_INTERVAL_MANUALLY) {
-			ContentResolver.setSyncAutomatically(account, authority, false);
-		} else {
-			ContentResolver.setSyncAutomatically(account, authority, true);
-			ContentResolver.addPeriodicSync(account, authority, new Bundle(), seconds);
-		}
-	}
-
-    public Integer getTimeRangePastDays() {
-        String strDays = accountManager.getUserData(account, KEY_TIME_RANGE_PAST_DAYS);
-        if (strDays != null) {
-            int days = Integer.valueOf(strDays);
-            return days < 0 ? null : days;
-        } else
-            return DEFAULT_TIME_RANGE_PAST_DAYS;
-    }
-
-    public void setTimeRangePastDays(Integer days) {
-        accountManager.setUserData(account, KEY_TIME_RANGE_PAST_DAYS, String.valueOf(days == null ? -1 : days));
-    }
-
-	
-	// update from previous account settings
-	
-	private void update(int fromVersion) {
-		for (int toVersion = fromVersion + 1; toVersion <= CURRENT_VERSION; toVersion++) {
-            App.log.info("Updating account " + account.name + " from version " + fromVersion + " to " + toVersion);
-            try {
-                Method updateProc = getClass().getDeclaredMethod("update_" + fromVersion + "_" + toVersion);
-                updateProc.invoke(this);
-            } catch (Exception e) {
-                App.log.log(Level.SEVERE, "Couldn't update account settings", e);
-            }
-            fromVersion = toVersion;
-        }
-	}
-
-    @SuppressWarnings({ "Recycle", "unused" })
-	private void update_0_1() throws URISyntaxException {
-		String	v0_principalURL = accountManager.getUserData(account, "principal_url"),
-				v0_addressBookPath = accountManager.getUserData(account, "addressbook_path");
-        App.log.fine("Old principal URL = " + v0_principalURL);
-        App.log.fine("Old address book path = " + v0_addressBookPath);
-		
-		URI principalURI = new URI(v0_principalURL);
-
-		// update address book
-		if (v0_addressBookPath != null) {
-			String addressBookURL = principalURI.resolve(v0_addressBookPath).toASCIIString();
-            App.log.fine("New address book URL = " + addressBookURL);
-			accountManager.setUserData(account, "addressbook_url", addressBookURL);
-		}
-		
-		// update calendars
-		ContentResolver resolver = context.getContentResolver();
-		Uri calendars = Calendars.CONTENT_URI.buildUpon()
-				.appendQueryParameter(Calendars.ACCOUNT_NAME, account.name)
-				.appendQueryParameter(Calendars.ACCOUNT_TYPE, account.type)
-				.appendQueryParameter(CalendarContract.CALLER_IS_SYNCADAPTER, "true").build();
-		@Cleanup Cursor cursor = resolver.query(calendars, new String[] { Calendars._ID, Calendars.NAME }, null, null, null);
-		while (cursor != null && cursor.moveToNext()) {
-			int id = cursor.getInt(0);
-			String	v0_path = cursor.getString(1),
-					v1_url = principalURI.resolve(v0_path).toASCIIString();
-            App.log.fine("Updating calendar #" + id + " name: " + v0_path + " -> " + v1_url);
-			Uri calendar = ContentUris.appendId(Calendars.CONTENT_URI.buildUpon()
-					.appendQueryParameter(Calendars.ACCOUNT_NAME, account.name)
-					.appendQueryParameter(Calendars.ACCOUNT_TYPE, account.type)
-					.appendQueryParameter(CalendarContract.CALLER_IS_SYNCADAPTER, "true"), id).build();
-			ContentValues newValues = new ContentValues(1);
-			newValues.put(Calendars.NAME, v1_url);
-			if (resolver.update(calendar, newValues, null, null) != 1)
-                App.log.fine("Number of modified calendars != 1");
-		}
-
-		accountManager.setUserData(account, "principal_url", null);
-		accountManager.setUserData(account, "addressbook_path", null);
-
-		accountManager.setUserData(account, KEY_SETTINGS_VERSION, "1");
-	}
-
-    @SuppressWarnings({ "Recycle", "unused" })
-    private void update_1_2() throws ContactsStorageException {
-        /* - KEY_ADDRESSBOOK_URL ("addressbook_url"),
-           - KEY_ADDRESSBOOK_CTAG ("addressbook_ctag"),
-           - KEY_ADDRESSBOOK_VCARD_VERSION ("addressbook_vcard_version") are not used anymore (now stored in ContactsContract.SyncState)
-           - KEY_LAST_ANDROID_VERSION ("last_android_version") has been added
-        */
-
-        // move previous address book info to ContactsContract.SyncState
-        @Cleanup("release") ContentProviderClient provider = context.getContentResolver().acquireContentProviderClient(ContactsContract.AUTHORITY);
-        if (provider == null)
-            throw new ContactsStorageException("Couldn't access Contacts provider");
-
-        LocalAddressBook addr = new LocalAddressBook(account, provider);
-
-        // until now, ContactsContract.Settings.UNGROUPED_VISIBLE was not set explicitly
-        ContentValues values = new ContentValues();
-        values.put(ContactsContract.Settings.UNGROUPED_VISIBLE, 1);
-        addr.updateSettings(values);
-
-        String url = accountManager.getUserData(account, "addressbook_url");
-        if (!TextUtils.isEmpty(url))
-            addr.setURL(url);
-        accountManager.setUserData(account, "addressbook_url", null);
-
-        String cTag = accountManager.getUserData(account, "addressbook_ctag");
-        if (!TextUtils.isEmpty(cTag))
-            addr.setCTag(cTag);
-        accountManager.setUserData(account, "addressbook_ctag", null);
-
-        accountManager.setUserData(account, KEY_SETTINGS_VERSION, "2");
-    }
-
-    @SuppressWarnings({ "Recycle", "unused" })
-    private void update_2_3() {
-        // Don't show a warning for Android updates anymore
-        accountManager.setUserData(account, "last_android_version", null);
-
-        Long serviceCardDAV = null, serviceCalDAV = null;
-
-        ServiceDB.OpenHelper dbHelper = new ServiceDB.OpenHelper(context);
-        try {
-            SQLiteDatabase db = dbHelper.getWritableDatabase();
-            // we have to create the WebDAV Service database only from the old address book, calendar and task list URLs
-
-            // CardDAV: migrate address books
-            ContentProviderClient client = context.getContentResolver().acquireContentProviderClient(ContactsContract.AUTHORITY);
-            if (client != null)
-                try {
-                    LocalAddressBook addrBook = new LocalAddressBook(account, client);
-                    String url = addrBook.getURL();
-                    if (url != null) {
-                        App.log.fine("Migrating address book " + url);
-
-                        // insert CardDAV service
-                        ContentValues values = new ContentValues();
-                        values.put(Services.ACCOUNT_NAME, account.name);
-                        values.put(Services.SERVICE, Services.SERVICE_CARDDAV);
-                        serviceCardDAV = db.insert(Services._TABLE, null, values);
-
-                        // insert address book
-                        values.clear();
-                        values.put(Collections.SERVICE_ID, serviceCardDAV);
-                        values.put(Collections.URL, url);
-                        values.put(Collections.SYNC, 1);
-                        db.insert(Collections._TABLE, null, values);
-
-                        // insert home set
-                        HttpUrl homeSet = HttpUrl.parse(url).resolve("../");
-                        values.clear();
-                        values.put(HomeSets.SERVICE_ID, serviceCardDAV);
-                        values.put(HomeSets.URL, homeSet.toString());
-                        db.insert(HomeSets._TABLE, null, values);
-                    }
-
-                } catch (ContactsStorageException e) {
-                    App.log.log(Level.SEVERE, "Couldn't migrate address book", e);
-                } finally {
-                    client.release();
-                }
-
-            // CalDAV: migrate calendars + task lists
-            Set<String> collections = new HashSet<>();
-            Set<HttpUrl> homeSets = new HashSet<>();
-
-            client = context.getContentResolver().acquireContentProviderClient(CalendarContract.AUTHORITY);
-            if (client != null)
-                try {
-                    LocalCalendar calendars[] = (LocalCalendar[])LocalCalendar.find(account, client, LocalCalendar.Factory.INSTANCE, null, null);
-                    for (LocalCalendar calendar : calendars) {
-                        String url = calendar.getName();
-                        App.log.fine("Migrating calendar " + url);
-                        collections.add(url);
-                        homeSets.add(HttpUrl.parse(url).resolve("../"));
-                    }
-                } catch (CalendarStorageException e) {
-                    App.log.log(Level.SEVERE, "Couldn't migrate calendars", e);
-                } finally {
-                    client.release();
-                }
-
-            TaskProvider provider = LocalTaskList.acquireTaskProvider(context.getContentResolver());
-            if (provider != null)
-                try {
-                    LocalTaskList[] taskLists = (LocalTaskList[])LocalTaskList.find(account, provider, LocalTaskList.Factory.INSTANCE, null, null);
-                    for (LocalTaskList taskList : taskLists) {
-                        String url = taskList.getSyncId();
-                        App.log.fine("Migrating task list " + url);
-                        collections.add(url);
-                        homeSets.add(HttpUrl.parse(url).resolve("../"));
-                    }
-                } catch (CalendarStorageException e) {
-                    App.log.log(Level.SEVERE, "Couldn't migrate task lists", e);
-                } finally {
-                    provider.close();
-                }
-
-            if (!collections.isEmpty()) {
-                // insert CalDAV service
-                ContentValues values = new ContentValues();
-                values.put(Services.ACCOUNT_NAME, account.name);
-                values.put(Services.SERVICE, Services.SERVICE_CALDAV);
-                serviceCalDAV = db.insert(Services._TABLE, null, values);
-
-                // insert collections
-                for (String url : collections) {
-                    values.clear();
-                    values.put(Collections.SERVICE_ID, serviceCalDAV);
-                    values.put(Collections.URL, url);
-                    values.put(Collections.SYNC, 1);
-                    db.insert(Collections._TABLE, null, values);
-                }
-
-                // insert home sets
-                for (HttpUrl homeSet : homeSets) {
-                    values.clear();
-                    values.put(HomeSets.SERVICE_ID, serviceCalDAV);
-                    values.put(HomeSets.URL, homeSet.toString());
-                    db.insert(HomeSets._TABLE, null, values);
-                }
-            }
-        } finally {
-            dbHelper.close();
-        }
-
-        // initiate service detection (refresh) to get display names, colors etc.
-        Intent refresh = new Intent(context, DavService.class);
-        refresh.setAction(DavService.ACTION_REFRESH_COLLECTIONS);
-        if (serviceCardDAV != null) {
-            refresh.putExtra(DavService.EXTRA_DAV_SERVICE_ID, serviceCardDAV);
-            context.startService(refresh);
-        }
-        if (serviceCalDAV != null) {
-            refresh.putExtra(DavService.EXTRA_DAV_SERVICE_ID, serviceCalDAV);
-            context.startService(refresh);
-        }
-
-        accountManager.setUserData(account, KEY_SETTINGS_VERSION, "3");
-    }
-
-}

app/src/main/java/at/bitfire/davdroid/AccountSettings.kt

@@ -0,0 +1,527 @@
+/*
+ * Copyright © Ricki Hirner (bitfire web engineering).
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the GNU Public License v3.0
+ * which accompanies this distribution, and is available at
+ * http://www.gnu.org/licenses/gpl.html
+ */
+package at.bitfire.davdroid
+
+import android.accounts.Account
+import android.accounts.AccountManager
+import android.content.*
+import android.os.Build
+import android.os.Bundle
+import android.os.Parcel
+import android.os.RemoteException
+import android.provider.CalendarContract
+import android.provider.ContactsContract
+import at.bitfire.davdroid.log.Logger
+import at.bitfire.davdroid.model.CollectionInfo
+import at.bitfire.davdroid.model.Credentials
+import at.bitfire.davdroid.model.ServiceDB
+import at.bitfire.davdroid.model.ServiceDB.*
+import at.bitfire.davdroid.model.ServiceDB.Collections
+import at.bitfire.davdroid.resource.LocalAddressBook
+import at.bitfire.davdroid.resource.LocalCalendar
+import at.bitfire.davdroid.resource.LocalTaskList
+import at.bitfire.davdroid.settings.ISettings
+import at.bitfire.ical4android.AndroidCalendar
+import at.bitfire.ical4android.AndroidTaskList
+import at.bitfire.ical4android.CalendarStorageException
+import at.bitfire.ical4android.TaskProvider
+import at.bitfire.vcard4android.ContactsStorageException
+import at.bitfire.vcard4android.GroupMethod
+import okhttp3.HttpUrl
+import org.apache.commons.lang3.StringUtils
+import org.dmfs.tasks.contract.TaskContract
+import java.util.*
+import java.util.logging.Level
+
+class AccountSettings @Throws(InvalidAccountException::class) constructor(
+        val context: Context,
+        val settings: ISettings,
+        val account: Account
+) {
+
+    companion object {
+
+        val CURRENT_VERSION = 8
+        val KEY_SETTINGS_VERSION = "version"
+
+        val KEY_USERNAME = "user_name"
+        val KEY_CERTIFICATE_ALIAS = "certificate_alias"
+
+        val KEY_WIFI_ONLY = "wifi_only"               // sync on WiFi only (default: false)
+        val KEY_WIFI_ONLY_SSIDS = "wifi_only_ssids"   // restrict sync to specific WiFi SSIDs
+
+        /** Time range limitation to the past [in days]
+        value = null            default value (DEFAULT_TIME_RANGE_PAST_DAYS)
+        < 0 (-1)          no limit
+        >= 0              entries more than n days in the past won't be synchronized
+         */
+        val KEY_TIME_RANGE_PAST_DAYS = "time_range_past_days"
+        val DEFAULT_TIME_RANGE_PAST_DAYS = 90
+
+        /* Whether DAVdroid sets the local calendar color to the value from service DB at every sync
+           value = null (not existing)     true (default)
+                   "0"                     false */
+        val KEY_MANAGE_CALENDAR_COLORS = "manage_calendar_colors"
+
+        /* Whether DAVdroid populates and uses CalendarContract.Colors
+           value = null (not existing)     false (default)
+                   "1"                     true */
+        val KEY_EVENT_COLORS = "event_colors"
+
+        /** Contact group method:
+        value = null (not existing)     groups as separate VCards (default)
+        "CATEGORIES"            groups are per-contact CATEGORIES
+         */
+        val KEY_CONTACT_GROUP_METHOD = "contact_group_method"
+
+        @JvmField
+        val SYNC_INTERVAL_MANUALLY = -1L
+
+        fun initialUserData(credentials: Credentials): Bundle {
+            val bundle = Bundle(2)
+            bundle.putString(KEY_SETTINGS_VERSION, CURRENT_VERSION.toString())
+
+            when (credentials.type) {
+                Credentials.Type.UsernamePassword ->
+                    bundle.putString(KEY_USERNAME, credentials.userName)
+                Credentials.Type.ClientCertificate ->
+                    bundle.putString(KEY_CERTIFICATE_ALIAS, credentials.certificateAlias)
+            }
+
+            return bundle
+        }
+
+    }
+
+
+    val accountManager: AccountManager = AccountManager.get(context)
+
+    init {
+        synchronized(AccountSettings::class.java) {
+            val versionStr = accountManager.getUserData(account, KEY_SETTINGS_VERSION) ?: throw InvalidAccountException(account)
+            var version = 0
+            try {
+                version = Integer.parseInt(versionStr)
+            } catch (e: NumberFormatException) {
+            }
+            Logger.log.fine("Account ${account.name} has version $version, current version: $CURRENT_VERSION")
+
+            if (version < CURRENT_VERSION)
+                update(version)
+        }
+    }
+
+
+    // authentication settings
+
+    fun credentials() = Credentials(
+            accountManager.getUserData(account, KEY_USERNAME),
+            accountManager.getPassword(account),
+            accountManager.getUserData(account, KEY_CERTIFICATE_ALIAS)
+    )
+
+    fun credentials(credentials: Credentials) {
+        accountManager.setUserData(account, KEY_USERNAME, credentials.userName)
+        accountManager.setPassword(account, credentials.password)
+        accountManager.setUserData(account, KEY_CERTIFICATE_ALIAS, credentials.certificateAlias)
+    }
+
+
+    // sync. settings
+
+    fun getSyncInterval(authority: String): Long? {
+        if (ContentResolver.getIsSyncable(account, authority) <= 0)
+            return null
+
+        return if (ContentResolver.getSyncAutomatically(account, authority))
+            ContentResolver.getPeriodicSyncs(account, authority).firstOrNull()?.period ?: SYNC_INTERVAL_MANUALLY
+        else
+            SYNC_INTERVAL_MANUALLY
+    }
+
+    fun setSyncInterval(authority: String, seconds: Long) {
+        if (seconds == SYNC_INTERVAL_MANUALLY) {
+            ContentResolver.setSyncAutomatically(account, authority, false)
+        } else {
+            ContentResolver.setSyncAutomatically(account, authority, true)
+            ContentResolver.addPeriodicSync(account, authority, Bundle(), seconds)
+        }
+    }
+
+    fun getSyncWifiOnly() = if (settings.has(KEY_WIFI_ONLY))
+            settings.getBoolean(KEY_WIFI_ONLY, false)
+                else
+            accountManager.getUserData(account, KEY_WIFI_ONLY) != null
+    fun setSyncWiFiOnly(wiFiOnly: Boolean) =
+            accountManager.setUserData(account, KEY_WIFI_ONLY, if (wiFiOnly) "1" else null)
+
+    fun getSyncWifiOnlySSIDs(): List<String>? = (if (settings.has(KEY_WIFI_ONLY_SSIDS))
+                settings.getString(KEY_WIFI_ONLY_SSIDS, null)
+            else
+                accountManager.getUserData(account, KEY_WIFI_ONLY_SSIDS))?.split(',')
+    fun setSyncWifiOnlySSIDs(ssids: List<String>?) =
+            accountManager.setUserData(account, KEY_WIFI_ONLY_SSIDS, StringUtils.trimToNull(ssids?.joinToString(",")))
+
+
+    // CalDAV settings
+
+    fun getTimeRangePastDays(): Int? {
+        val strDays = accountManager.getUserData(account, KEY_TIME_RANGE_PAST_DAYS)
+        if (strDays != null) {
+            val days = Integer.valueOf(strDays)
+            return if (days < 0) null else days
+        } else
+            return DEFAULT_TIME_RANGE_PAST_DAYS
+    }
+
+    fun setTimeRangePastDays(days: Int?) =
+            accountManager.setUserData(account, KEY_TIME_RANGE_PAST_DAYS, (days ?: -1).toString())
+
+    fun getManageCalendarColors() = if (settings.has(KEY_MANAGE_CALENDAR_COLORS))
+        settings.getBoolean(KEY_MANAGE_CALENDAR_COLORS, false)
+    else
+        accountManager.getUserData(account, KEY_MANAGE_CALENDAR_COLORS) == null
+    fun setManageCalendarColors(manage: Boolean) =
+            accountManager.setUserData(account, KEY_MANAGE_CALENDAR_COLORS, if (manage) null else "0")
+
+    fun getEventColors() = if (settings.has(KEY_EVENT_COLORS))
+            settings.getBoolean(KEY_EVENT_COLORS, false)
+                else
+            accountManager.getUserData(account, KEY_EVENT_COLORS) != null
+    fun setEventColors(useColors: Boolean) =
+            accountManager.setUserData(account, KEY_EVENT_COLORS, if (useColors) "1" else null)
+
+    // CardDAV settings
+
+    fun getGroupMethod(): GroupMethod {
+        val name = settings.getString(KEY_CONTACT_GROUP_METHOD, null) ?:
+                accountManager.getUserData(account, KEY_CONTACT_GROUP_METHOD)
+        if (name != null)
+            try {
+                return GroupMethod.valueOf(name)
+            }
+            catch (e: IllegalArgumentException) {
+            }
+        return GroupMethod.GROUP_VCARDS
+    }
+
+    fun setGroupMethod(method: GroupMethod) {
+        accountManager.setUserData(account, KEY_CONTACT_GROUP_METHOD, method.name)
+    }
+
+
+    // update from previous account settings
+
+    private fun update(baseVersion: Int) {
+        for (toVersion in baseVersion+1 .. CURRENT_VERSION) {
+            val fromVersion = toVersion-1
+            Logger.log.info("Updating account ${account.name} from version $fromVersion to $toVersion")
+            try {
+                val updateProc = this::class.java.getDeclaredMethod("update_${fromVersion}_$toVersion")
+                updateProc.invoke(this)
+
+                Logger.log.info("Account version update successful")
+                accountManager.setUserData(account, KEY_SETTINGS_VERSION, toVersion.toString())
+            } catch (e: Exception) {
+                Logger.log.log(Level.SEVERE, "Couldn't update account settings", e)
+            }
+        }
+    }
+
+    @Suppress("unused")
+    private fun update_7_8() {
+        TaskProvider.acquire(context, TaskProvider.ProviderName.OpenTasks)?.let { provider ->
+            // ETag is now in sync_version instead of sync1
+            // UID  is now in _uid         instead of sync2
+            val cursor = provider.client.query(TaskProvider.syncAdapterUri(provider.tasksUri(), account),
+                    arrayOf(TaskContract.Tasks._ID, TaskContract.Tasks.SYNC1, TaskContract.Tasks.SYNC2),
+                    "${TaskContract.Tasks.ACCOUNT_TYPE}=? AND ${TaskContract.Tasks.ACCOUNT_NAME}=?",
+                    arrayOf(account.type, account.name), null)
+            while (cursor.moveToNext()) {
+                val id = cursor.getLong(0)
+                val eTag = cursor.getString(1)
+                val uid = cursor.getString(2)
+                val values = ContentValues(4)
+                values.put(TaskContract.Tasks._UID, uid)
+                values.put(TaskContract.Tasks.SYNC_VERSION, eTag)
+                values.putNull(TaskContract.Tasks.SYNC1)
+                values.putNull(TaskContract.Tasks.SYNC2)
+                Logger.log.log(Level.FINER, "Updating task $id", values)
+                provider.client.update(
+                        TaskProvider.syncAdapterUri(ContentUris.withAppendedId(provider.tasksUri(), id), account),
+                        values, null, null)
+            }
+        }
+    }
+
+    @Suppress("unused")
+    private fun update_6_7() {
+        // add calendar colors
+        context.contentResolver.acquireContentProviderClient(CalendarContract.AUTHORITY)?.let { provider ->
+            try {
+                AndroidCalendar.insertColors(provider, account)
+            } finally {
+                if (Build.VERSION.SDK_INT >= 24)
+                    provider.close()
+                else
+                    provider.release()
+            }
+        }
+
+        // update allowed WiFi settings key
+        val onlySSID = accountManager.getUserData(account, "wifi_only_ssid")
+        accountManager.setUserData(account, KEY_WIFI_ONLY_SSIDS, onlySSID)
+        accountManager.setUserData(account, "wifi_only_ssid", null)
+    }
+
+    @Suppress("unused")
+    private fun update_5_6() {
+        context.contentResolver.acquireContentProviderClient(ContactsContract.AUTHORITY)?.let { provider ->
+            val parcel = Parcel.obtain()
+            try {
+                // don't run syncs during the migration
+                ContentResolver.setIsSyncable(account, ContactsContract.AUTHORITY, 0)
+                ContentResolver.setIsSyncable(account, context.getString(R.string.address_books_authority), 0)
+                ContentResolver.cancelSync(account, null)
+
+                // get previous address book settings (including URL)
+                val raw = ContactsContract.SyncState.get(provider, account)
+                if (raw == null)
+                    Logger.log.info("No contacts sync state, ignoring account")
+                else {
+                    parcel.unmarshall(raw, 0, raw.size)
+                    parcel.setDataPosition(0)
+                    val params = parcel.readBundle()
+                    val url = params.getString("url")
+                    if (url == null)
+                        Logger.log.info("No address book URL, ignoring account")
+                    else {
+                        // create new address book
+                        val info = CollectionInfo(url)
+                        info.type = CollectionInfo.Type.ADDRESS_BOOK
+                        info.displayName = account.name
+                        Logger.log.log(Level.INFO, "Creating new address book account", url)
+                        val addressBookAccount = Account(LocalAddressBook.accountName(account, info), context.getString(R.string.account_type_address_book))
+                        if (!accountManager.addAccountExplicitly(addressBookAccount, null, LocalAddressBook.initialUserData(account, info.url)))
+                            throw ContactsStorageException("Couldn't create address book account")
+
+                        // move contacts to new address book
+                        Logger.log.info("Moving contacts from $account to $addressBookAccount")
+                        val newAccount = ContentValues(2)
+                        newAccount.put(ContactsContract.RawContacts.ACCOUNT_NAME, addressBookAccount.name)
+                        newAccount.put(ContactsContract.RawContacts.ACCOUNT_TYPE, addressBookAccount.type)
+                        val affected = provider.update(ContactsContract.RawContacts.CONTENT_URI.buildUpon()
+                                .appendQueryParameter(ContactsContract.RawContacts.ACCOUNT_NAME, account.name)
+                                .appendQueryParameter(ContactsContract.RawContacts.ACCOUNT_TYPE, account.type)
+                                .appendQueryParameter(ContactsContract.CALLER_IS_SYNCADAPTER, "true").build(),
+                                newAccount,
+                                "${ContactsContract.RawContacts.ACCOUNT_NAME}=? AND ${ContactsContract.RawContacts.ACCOUNT_TYPE}=?",
+                                arrayOf(account.name, account.type))
+                        Logger.log.info("$affected contacts moved to new address book")
+                    }
+
+                    ContactsContract.SyncState.set(provider, account, null)
+                }
+            } catch(e: RemoteException) {
+                throw ContactsStorageException("Couldn't migrate contacts to new address book", e)
+            } finally {
+                parcel.recycle()
+                if (Build.VERSION.SDK_INT >= 24)
+                    provider.close()
+                else
+                    provider.release()
+            }
+        }
+
+        // update version number so that further syncs don't repeat the migration
+        accountManager.setUserData(account, KEY_SETTINGS_VERSION, "6")
+
+        // request sync of new address book account
+        ContentResolver.setIsSyncable(account, context.getString(R.string.address_books_authority), 1)
+        setSyncInterval(context.getString(R.string.address_books_authority), Constants.DEFAULT_SYNC_INTERVAL)
+    }
+
+    /* Android 7.1.1 OpenTasks fix */
+    @Suppress("unused")
+    private fun update_4_5() {
+        // call PackageChangedReceiver which then enables/disables OpenTasks sync when it's (not) available
+        PackageChangedReceiver.updateTaskSync(context)
+    }
+
+    @Suppress("unused")
+    private fun update_3_4() {
+        setGroupMethod(GroupMethod.CATEGORIES)
+    }
+
+    @Suppress("unused")
+    private fun update_2_3() {
+        // Don't show a warning for Android updates anymore
+        accountManager.setUserData(account, "last_android_version", null)
+
+        var serviceCardDAV: Long? = null
+        var serviceCalDAV: Long? = null
+
+        ServiceDB.OpenHelper(context).use { dbHelper ->
+            val db = dbHelper.writableDatabase
+            // we have to create the WebDAV Service database only from the old address book, calendar and task list URLs
+
+            // CardDAV: migrate address books
+            context.contentResolver.acquireContentProviderClient(ContactsContract.AUTHORITY)?.let { client ->
+                try {
+                    val addrBook = LocalAddressBook(context, account, client)
+                    val url = addrBook.getURL()
+                    Logger.log.fine("Migrating address book $url")
+
+                    // insert CardDAV service
+                    val values = ContentValues(3)
+                    values.put(Services.ACCOUNT_NAME, account.name)
+                    values.put(Services.SERVICE, Services.SERVICE_CARDDAV)
+                    serviceCardDAV = db.insert(Services._TABLE, null, values)
+
+                    // insert address book
+                    values.clear()
+                    values.put(Collections.SERVICE_ID, serviceCardDAV)
+                    values.put(Collections.URL, url)
+                    values.put(Collections.SYNC, 1)
+                    db.insert(Collections._TABLE, null, values)
+
+                    // insert home set
+                    HttpUrl.parse(url)?.let {
+                        val homeSet = it.resolve("../")
+                        values.clear()
+                        values.put(HomeSets.SERVICE_ID, serviceCardDAV)
+                        values.put(HomeSets.URL, homeSet.toString())
+                        db.insert(HomeSets._TABLE, null, values)
+                    }
+                } catch (e: ContactsStorageException) {
+                    Logger.log.log(Level.SEVERE, "Couldn't migrate address book", e)
+                } finally {
+                    if (Build.VERSION.SDK_INT >= 24)
+                        client.close()
+                    else
+                        @Suppress("deprecation")
+                        client.release()
+                }
+            }
+
+            // CalDAV: migrate calendars + task lists
+            val collections = HashSet<String>()
+            val homeSets = HashSet<HttpUrl>()
+
+            context.contentResolver.acquireContentProviderClient(CalendarContract.AUTHORITY)?.let { client ->
+                try {
+                    val calendars = AndroidCalendar.find(account, client, LocalCalendar.Factory, null, null)
+                    for (calendar in calendars)
+                        calendar.name?.let { url ->
+                            Logger.log.fine("Migrating calendar $url")
+                            collections.add(url)
+                            HttpUrl.parse(url)?.resolve("../")?.let { homeSets.add(it) }
+                        }
+                } catch (e: CalendarStorageException) {
+                    Logger.log.log(Level.SEVERE, "Couldn't migrate calendars", e)
+                } finally {
+                    if (Build.VERSION.SDK_INT >= 24)
+                        client.close()
+                    else
+                        @Suppress("deprecation")
+                        client.release()
+                }
+            }
+
+            AndroidTaskList.acquireTaskProvider(context)?.use { provider ->
+                try {
+                    val taskLists = AndroidTaskList.find(account, provider, LocalTaskList.Factory, null, null)
+                    for (taskList in taskLists)
+                        taskList.syncId?.let { url ->
+                            Logger.log.fine("Migrating task list $url")
+                            collections.add(url)
+                            HttpUrl.parse(url)?.resolve("../")?.let { homeSets.add(it) }
+                        }
+                } catch (e: CalendarStorageException) {
+                    Logger.log.log(Level.SEVERE, "Couldn't migrate task lists", e)
+                }
+            }
+
+            if (!collections.isEmpty()) {
+                // insert CalDAV service
+                val values = ContentValues(3)
+                values.put(Services.ACCOUNT_NAME, account.name)
+                values.put(Services.SERVICE, Services.SERVICE_CALDAV)
+                serviceCalDAV = db.insert(Services._TABLE, null, values)
+
+                // insert collections
+                for (url in collections) {
+                    values.clear()
+                    values.put(Collections.SERVICE_ID, serviceCalDAV)
+                    values.put(Collections.URL, url)
+                    values.put(Collections.SYNC, 1)
+                    db.insert(Collections._TABLE, null, values)
+                }
+
+                // insert home sets
+                for (homeSet in homeSets) {
+                    values.clear()
+                    values.put(HomeSets.SERVICE_ID, serviceCalDAV)
+                    values.put(HomeSets.URL, homeSet.toString())
+                    db.insert(HomeSets._TABLE, null, values)
+                }
+            }
+        }
+
+        // initiate service detection (refresh) to get display names, colors etc.
+        val refresh = Intent(context, DavService::class.java)
+        refresh.action = DavService.ACTION_REFRESH_COLLECTIONS
+        serviceCardDAV?.let {
+            refresh.putExtra(DavService.EXTRA_DAV_SERVICE_ID, it)
+            context.startService(refresh)
+        }
+        serviceCalDAV?.let {
+            refresh.putExtra(DavService.EXTRA_DAV_SERVICE_ID, it)
+            context.startService(refresh)
+        }
+    }
+
+    @Suppress("unused")
+    private fun update_1_2() {
+        /* - KEY_ADDRESSBOOK_URL ("addressbook_url"),
+           - KEY_ADDRESSBOOK_CTAG ("addressbook_ctag"),
+           - KEY_ADDRESSBOOK_VCARD_VERSION ("addressbook_vcard_version") are not used anymore (now stored in ContactsContract.SyncState)
+           - KEY_LAST_ANDROID_VERSION ("last_android_version") has been added
+        */
+
+        // move previous address book info to ContactsContract.SyncState
+        val provider = context.contentResolver.acquireContentProviderClient(ContactsContract.AUTHORITY) ?:
+            throw ContactsStorageException("Couldn't access Contacts provider")
+
+        try {
+            val addr = LocalAddressBook(context, account, provider)
+
+            // until now, ContactsContract.Settings.UNGROUPED_VISIBLE was not set explicitly
+            val values = ContentValues()
+            values.put(ContactsContract.Settings.UNGROUPED_VISIBLE, 1)
+            addr.updateSettings(values)
+
+            val url = accountManager.getUserData(account, "addressbook_url")
+            if (!url.isNullOrEmpty())
+                addr.setURL(url)
+            accountManager.setUserData(account, "addressbook_url", null)
+
+            val cTag = accountManager.getUserData (account, "addressbook_ctag")
+            if (!cTag.isNullOrEmpty())
+                addr.setCTag(cTag)
+            accountManager.setUserData(account, "addressbook_ctag", null)
+        } finally {
+            if (Build.VERSION.SDK_INT >= 24)
+                provider.close()
+            else
+                @Suppress("deprecation")
+                provider.release()
+        }
+    }
+
+}

app/src/main/java/at/bitfire/davdroid/AccountsChangedReceiver.java

@@ -1,43 +0,0 @@
-/*
- * Copyright © 2013 – 2016 Ricki Hirner (bitfire web engineering).
- * All rights reserved. This program and the accompanying materials
- * are made available under the terms of the GNU Public License v3.0
- * which accompanies this distribution, and is available at
- * http://www.gnu.org/licenses/gpl.html
- */
-
-package at.bitfire.davdroid;
-
-import android.accounts.OnAccountsUpdateListener;
-import android.content.BroadcastReceiver;
-import android.content.Context;
-import android.content.Intent;
-
-import java.util.LinkedList;
-import java.util.List;
-
-public class AccountsChangedReceiver extends BroadcastReceiver {
-
-    protected static final List<OnAccountsUpdateListener> listeners = new LinkedList<>();
-
-    @Override
-    public void onReceive(Context context, Intent intent) {
-        Intent serviceIntent = new Intent(context, DavService.class);
-        serviceIntent.setAction(DavService.ACTION_ACCOUNTS_UPDATED);
-        context.startService(serviceIntent);
-
-        for (OnAccountsUpdateListener listener : listeners)
-            listener.onAccountsUpdated(null);
-    }
-
-    public static void registerListener(OnAccountsUpdateListener listener, boolean callImmediately) {
-        listeners.add(listener);
-        if (callImmediately)
-            listener.onAccountsUpdated(null);
-    }
-
-    public static void unregisterListener(OnAccountsUpdateListener listener) {
-        listeners.remove(listener);
-    }
-
-}

app/src/main/java/at/bitfire/davdroid/App.java

@@ -1,153 +0,0 @@
-/*
- * Copyright © 2013 – 2016 Ricki Hirner (bitfire web engineering).
- * All rights reserved. This program and the accompanying materials
- * are made available under the terms of the GNU Public License v3.0
- * which accompanies this distribution, and is available at
- * http://www.gnu.org/licenses/gpl.html
- */
-
-package at.bitfire.davdroid;
-
-import android.accounts.Account;
-import android.app.ActivityManager;
-import android.app.Application;
-import android.app.Notification;
-import android.app.NotificationManager;
-import android.app.PendingIntent;
-import android.content.ContentResolver;
-import android.content.Intent;
-import android.content.SharedPreferences;
-import android.graphics.drawable.BitmapDrawable;
-import android.net.Uri;
-import android.os.*;
-import android.os.Process;
-import android.support.v4.app.ActivityManagerCompat;
-import android.support.v7.app.NotificationCompat;
-import android.util.Log;
-
-import org.apache.commons.lang3.time.DateFormatUtils;
-
-import java.io.File;
-import java.io.IOException;
-import java.lang.reflect.Method;
-import java.util.logging.FileHandler;
-import java.util.logging.Handler;
-import java.util.logging.Level;
-import java.util.logging.Logger;
-
-import javax.net.ssl.HostnameVerifier;
-
-import at.bitfire.davdroid.log.LogcatHandler;
-import at.bitfire.davdroid.log.PlainTextFormatter;
-import de.duenndns.ssl.MemorizingTrustManager;
-import lombok.Getter;
-import okhttp3.internal.tls.OkHostnameVerifier;
-
-public class App extends Application implements SharedPreferences.OnSharedPreferenceChangeListener {
-    public static final String
-            PREF_FILE = "davdroid_preferences",             // preference file name
-            PREF_LOG_TO_FILE = "log_to_file";               // boolean: external logging enabled
-
-    @Getter
-    private static MemorizingTrustManager memorizingTrustManager;
-
-    @Getter
-    private static SSLSocketFactoryCompat sslSocketFactoryCompat;
-
-    @Getter
-    private static HostnameVerifier hostnameVerifier;
-
-    public final static Logger log = Logger.getLogger("davdroid");
-
-    @Getter
-    private static SharedPreferences preferences;
-
-    @Override
-    public void onCreate() {
-        super.onCreate();
-
-        preferences = getSharedPreferences(PREF_FILE, MODE_PRIVATE);
-        preferences.registerOnSharedPreferenceChangeListener(this);
-
-        // initialize MemorizingTrustManager
-        memorizingTrustManager = new MemorizingTrustManager(this);
-        sslSocketFactoryCompat = new SSLSocketFactoryCompat(memorizingTrustManager);
-        hostnameVerifier = memorizingTrustManager.wrapHostnameVerifier(OkHostnameVerifier.INSTANCE);
-
-        // initializer logger
-        reinitLogger();
-    }
-
-    // won't be called in production
-    @Override
-    public void onTerminate() {
-        super.onTerminate();
-        preferences.unregisterOnSharedPreferenceChangeListener(this);
-    }
-
-    @Override
-    public void onSharedPreferenceChanged(SharedPreferences sharedPreferences, String key) {
-        if (PREF_LOG_TO_FILE.equals(key)) {
-            log.info("Logging preferences changed, initializing logger again");
-            reinitLogger();
-        }
-    }
-
-    private void reinitLogger() {
-        // don't use Android default logging, we have our own handlers
-        log.setUseParentHandlers(false);
-
-        boolean logToFile = preferences.getBoolean(PREF_LOG_TO_FILE, false),
-                logVerbose = logToFile || Log.isLoggable(log.getName(), Log.DEBUG);
-
-        // set logging level according to preferences
-        log.setLevel(logVerbose ? Level.ALL : Level.INFO);
-
-        // remove all handlers
-        for (Handler handler : log.getHandlers())
-            log.removeHandler(handler);
-
-        // add logcat handler
-        log.addHandler(LogcatHandler.INSTANCE);
-
-        NotificationManager nm = (NotificationManager)getSystemService(NOTIFICATION_SERVICE);
-        // log to external file according to preferences
-        if (logToFile) {
-            NotificationCompat.Builder builder = new NotificationCompat.Builder(this);
-            builder .setSmallIcon(R.drawable.ic_sd_storage_light)
-                    .setLargeIcon(((BitmapDrawable)getResources().getDrawable(R.drawable.ic_launcher)).getBitmap())
-                    .setContentTitle(getString(R.string.logging_davdroid_file_logging))
-                    .setLocalOnly(true);
-
-            File dir = getExternalFilesDir(null);
-            if (dir != null)
-                try {
-                    String pattern = new File(dir, "davdroid%u-" + DateFormatUtils.format(System.currentTimeMillis(), "yyyyMMdd-HHmmss") + ".txt").toString();
-                    log.info("Logging to " + pattern);
-
-                    FileHandler fileHandler = new FileHandler(pattern);
-                    fileHandler.setFormatter(PlainTextFormatter.DEFAULT);
-                    log.addHandler(fileHandler);
-                    builder .setContentText(dir.getPath())
-                            .setSubText(getString(R.string.logging_to_external_storage_warning))
-                            .setCategory(NotificationCompat.CATEGORY_STATUS)
-                            .setPriority(NotificationCompat.PRIORITY_HIGH)
-                            .setStyle(new NotificationCompat.BigTextStyle()
-                                    .bigText(getString(R.string.logging_to_external_storage, dir.getPath())))
-                            .setOngoing(true);
-
-                } catch (IOException e) {
-                    log.log(Level.SEVERE, "Couldn't create external log file", e);
-
-                    builder .setContentText(getString(R.string.logging_couldnt_create_file, e.getLocalizedMessage()))
-                            .setCategory(NotificationCompat.CATEGORY_ERROR);
-                }
-            else
-                builder.setContentText(getString(R.string.logging_no_external_storage));
-
-            nm.notify(Constants.NOTIFICATION_EXTERNAL_FILE_LOGGING, builder.build());
-        } else
-            nm.cancel(Constants.NOTIFICATION_EXTERNAL_FILE_LOGGING);
-    }
-
-}

app/src/main/java/at/bitfire/davdroid/App.kt

@@ -0,0 +1,56 @@
+/*
+ * Copyright © Ricki Hirner (bitfire web engineering).
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the GNU Public License v3.0
+ * which accompanies this distribution, and is available at
+ * http://www.gnu.org/licenses/gpl.html
+ */
+
+package at.bitfire.davdroid
+
+import android.app.Application
+import android.content.Context
+import android.graphics.Bitmap
+import android.graphics.drawable.BitmapDrawable
+import android.os.Build
+import android.support.v7.app.AppCompatDelegate
+import at.bitfire.davdroid.log.Logger
+
+class App: Application() {
+
+    companion object {
+
+        @JvmField val DISTRUST_SYSTEM_CERTIFICATES = "distrust_system_certs"
+        @JvmField val OVERRIDE_PROXY = "override_proxy"
+        @JvmField val OVERRIDE_PROXY_HOST = "override_proxy_host"
+        @JvmField val OVERRIDE_PROXY_PORT = "override_proxy_port"
+
+        @JvmField val OVERRIDE_PROXY_HOST_DEFAULT = "localhost"
+        @JvmField val OVERRIDE_PROXY_PORT_DEFAULT = 8118
+
+
+        @JvmStatic
+        fun getLauncherBitmap(context: Context): Bitmap? {
+            val drawableLogo = if (android.os.Build.VERSION.SDK_INT >= 21)
+                    context.getDrawable(R.mipmap.ic_launcher)
+                else
+                    @Suppress("deprecation")
+                    context.resources.getDrawable(R.mipmap.ic_launcher)
+            return if (drawableLogo is BitmapDrawable)
+                drawableLogo.bitmap
+            else
+                null
+        }
+
+    }
+
+
+    override fun onCreate() {
+        super.onCreate()
+        Logger.initialize(this)
+
+        if (Build.VERSION.SDK_INT <= 21)
+            AppCompatDelegate.setCompatVectorFromResourcesEnabled(true)
+    }
+
+}

app/src/main/java/at/bitfire/davdroid/ArrayUtils.java

@@ -1,33 +0,0 @@
-/*
- * Copyright © 2013 – 2015 Ricki Hirner (bitfire web engineering).
- * All rights reserved. This program and the accompanying materials
- * are made available under the terms of the GNU Public License v3.0
- * which accompanies this distribution, and is available at
- * http://www.gnu.org/licenses/gpl.html
- */
-package at.bitfire.davdroid;
-
-import java.lang.reflect.Array;
-
-public class ArrayUtils {
-
-	@SuppressWarnings("unchecked")
-	public static <T> T[][] partition(T[] bigArray, int max) {
-		int nItems = bigArray.length;
-		int nPartArrays = (nItems + max-1)/max;
-		
-		T[][] partArrays = (T[][])Array.newInstance(bigArray.getClass().getComponentType(), nPartArrays, 0); 
-		
-		// nItems is now the number of remaining items
-		for (int i = 0; nItems > 0; i++) {
-			int n = (nItems < max) ? nItems : max;
-			partArrays[i] = (T[])Array.newInstance(bigArray.getClass().getComponentType(), n); 
-			System.arraycopy(bigArray, i*max, partArrays[i], 0, n);
-			
-			nItems -= n;
-		}
-		
-		return partArrays;
-	}
-	
-}

app/src/main/java/at/bitfire/davdroid/Constants.java

@@ -1,27 +0,0 @@
-/*
- * Copyright © 2013 – 2015 Ricki Hirner (bitfire web engineering).
- * All rights reserved. This program and the accompanying materials
- * are made available under the terms of the GNU Public License v3.0
- * which accompanies this distribution, and is available at
- * http://www.gnu.org/licenses/gpl.html
- */
-package at.bitfire.davdroid;
-
-import android.net.Uri;
-
-public class Constants {
-
-	public static final String
-		ACCOUNT_TYPE = "bitfire.at.davdroid";
-
-    // notification IDs
-    public final static int
-            NOTIFICATION_ACCOUNT_SETTINGS_UPDATED = 0,
-            NOTIFICATION_EXTERNAL_FILE_LOGGING = 1,
-            NOTIFICATION_CONTACTS_SYNC = 10,
-            NOTIFICATION_CALENDAR_SYNC = 11,
-            NOTIFICATION_TASK_SYNC = 12;
-
-    public static final Uri webUri = Uri.parse("https://davdroid.bitfire.at/?pk_campaign=davdroid-app");
-
-}

app/src/main/java/at/bitfire/davdroid/Constants.kt

@@ -0,0 +1,23 @@
+/*
+ * Copyright © Ricki Hirner (bitfire web engineering).
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the GNU Public License v3.0
+ * which accompanies this distribution, and is available at
+ * http://www.gnu.org/licenses/gpl.html
+ */
+package at.bitfire.davdroid
+
+object Constants {
+
+    // notification IDs
+    @JvmField val NOTIFICATION_EXTERNAL_FILE_LOGGING = 1
+    @JvmField val NOTIFICATION_REFRESH_COLLECTIONS = 2
+    @JvmField val NOTIFICATION_CONTACTS_SYNC = 10
+    @JvmField val NOTIFICATION_CALENDAR_SYNC = 11
+    @JvmField val NOTIFICATION_TASK_SYNC = 12
+    @JvmField val NOTIFICATION_PERMISSIONS = 20
+
+    @JvmField
+    val DEFAULT_SYNC_INTERVAL = 4 * 3600L    // 4 hours
+
+}

app/src/main/java/at/bitfire/davdroid/CustomTlsSocketFactory.kt

@@ -0,0 +1,165 @@
+/*
+ * Copyright © Ricki Hirner (bitfire web engineering).
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the GNU Public License v3.0
+ * which accompanies this distribution, and is available at
+ * http://www.gnu.org/licenses/gpl.html
+ */
+
+package at.bitfire.davdroid
+
+import android.os.Build
+import at.bitfire.davdroid.log.Logger
+import java.io.IOException
+import java.net.InetAddress
+import java.net.Socket
+import java.security.GeneralSecurityException
+import java.util.*
+import javax.net.ssl.*
+
+/**
+ * Custom TLS socket factory with support for
+ *   - enabling/disabling algorithms depending on the Android version,
+ *   - client certificate authentication
+ */
+class CustomTlsSocketFactory(
+        keyManager: KeyManager?,
+        trustManager: X509TrustManager
+): SSLSocketFactory() {
+
+    private var delegate: SSLSocketFactory
+
+    companion object {
+        // Android 5.0+ (API level 21) provides reasonable default settings
+        // but it still allows SSLv3
+        // https://developer.android.com/reference/javax/net/ssl/SSLSocket.html
+        var protocols: Array<String>? = null
+        var cipherSuites: Array<String>? = null
+        init {
+            if (Build.VERSION.SDK_INT >= 23) {
+                // Since Android 6.0 (API level 23),
+                // - TLSv1.1 and TLSv1.2 is enabled by default
+                // - SSLv3 is disabled by default
+                // - all modern ciphers are activated by default
+                protocols = null
+                cipherSuites = null
+                Logger.log.fine("Using device default TLS protocols/ciphers")
+            } else {
+                (SSLSocketFactory.getDefault().createSocket() as? SSLSocket)?.use { socket ->
+                    try {
+                        /* set reasonable protocol versions */
+                        // - enable all supported protocols (enables TLSv1.1 and TLSv1.2 on Android <5.0)
+                        // - remove all SSL versions (especially SSLv3) because they're insecure now
+                        val _protocols = LinkedList<String>()
+                        for (protocol in socket.supportedProtocols.filterNot { it.contains("SSL", true) })
+                            _protocols += protocol
+                        Logger.log.info("Enabling (only) these TLS protocols: ${_protocols.joinToString(", ")}")
+                        protocols = _protocols.toTypedArray()
+
+                        /* set up reasonable cipher suites */
+                        val knownCiphers = arrayOf(
+                                // TLS 1.2
+                                "TLS_RSA_WITH_AES_256_GCM_SHA384",
+                                "TLS_RSA_WITH_AES_128_GCM_SHA256",
+                                "TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA256",
+                                "TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256",
+                                "TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384",
+                                "TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256",
+                                "TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256",
+                                // maximum interoperability
+                                "TLS_RSA_WITH_3DES_EDE_CBC_SHA",
+                                "SSL_RSA_WITH_3DES_EDE_CBC_SHA",
+                                "TLS_RSA_WITH_AES_128_CBC_SHA",
+                                // additionally
+                                "TLS_RSA_WITH_AES_256_CBC_SHA",
+                                "TLS_ECDHE_ECDSA_WITH_3DES_EDE_CBC_SHA",
+                                "TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA",
+                                "TLS_ECDHE_RSA_WITH_3DES_EDE_CBC_SHA",
+                                "TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA"
+                        )
+                        val availableCiphers = socket.supportedCipherSuites
+                        Logger.log.info("Available cipher suites: ${availableCiphers.joinToString(", ")}")
+
+                        /* For maximum security, preferredCiphers should *replace* enabled ciphers (thus
+                         * disabling ciphers which are enabled by default, but have become unsecure), but for
+                         * the security level of DAVdroid and maximum compatibility, disabling of insecure
+                         * ciphers should be a server-side task */
+
+                        // for the final set of enabled ciphers, take the ciphers enabled by default, ...
+                        val _cipherSuites = LinkedList<String>()
+                        _cipherSuites.addAll(socket.enabledCipherSuites)
+                        Logger.log.fine("Cipher suites enabled by default: ${_cipherSuites.joinToString(", ")}")
+                        // ... add explicitly allowed ciphers ...
+                        _cipherSuites.addAll(knownCiphers)
+                        // ... and keep only those which are actually available
+                        _cipherSuites.retainAll(availableCiphers)
+
+                        Logger.log.info("Enabling (only) these TLS ciphers: " + _cipherSuites.joinToString(", "))
+                        cipherSuites = _cipherSuites.toTypedArray()
+                    } catch (e: IOException) {
+                        Logger.log.severe("Couldn't determine default TLS settings")
+                    }
+                }
+            }
+        }
+    }
+
+
+    init {
+        try {
+            val sslContext = SSLContext.getInstance("TLS")
+            sslContext.init(
+                    if (keyManager != null) arrayOf(keyManager) else null,
+                    arrayOf(trustManager),
+                    null)
+            delegate = sslContext.socketFactory
+        } catch (e: GeneralSecurityException) {
+            throw IllegalStateException()      // system has no TLS
+        }
+    }
+
+    override fun getDefaultCipherSuites(): Array<String>? = cipherSuites ?: delegate.defaultCipherSuites
+    override fun getSupportedCipherSuites(): Array<String>? = cipherSuites ?: delegate.supportedCipherSuites
+
+    override fun createSocket(s: Socket, host: String, port: Int, autoClose: Boolean): Socket {
+        val ssl = delegate.createSocket(s, host, port, autoClose)
+        if (ssl is SSLSocket)
+            upgradeTLS(ssl)
+        return ssl
+    }
+
+    override fun createSocket(host: String, port: Int): Socket {
+        val ssl = delegate.createSocket(host, port)
+        if (ssl is SSLSocket)
+            upgradeTLS(ssl)
+        return ssl
+    }
+
+    override fun createSocket(host: String, port: Int, localHost: InetAddress, localPort: Int): Socket {
+        val ssl = delegate.createSocket(host, port, localHost, localPort)
+        if (ssl is SSLSocket)
+            upgradeTLS(ssl)
+        return ssl
+    }
+
+    override fun createSocket(host: InetAddress, port: Int): Socket {
+        val ssl = delegate.createSocket(host, port)
+        if (ssl is SSLSocket)
+            upgradeTLS(ssl)
+        return ssl
+    }
+
+    override fun createSocket(address: InetAddress, port: Int, localAddress: InetAddress, localPort: Int): Socket {
+        val ssl = delegate.createSocket(address, port, localAddress, localPort)
+        if (ssl is SSLSocket)
+            upgradeTLS(ssl)
+        return ssl
+    }
+
+
+    private fun upgradeTLS(ssl: SSLSocket) {
+        protocols?.let { ssl.enabledProtocols = it }
+        cipherSuites?.let { ssl.enabledCipherSuites = it }
+    }
+
+}

app/src/main/java/at/bitfire/davdroid/DavService.java

@@ -1,346 +0,0 @@
-/*
- * Copyright © 2013 – 2016 Ricki Hirner (bitfire web engineering).
- * All rights reserved. This program and the accompanying materials
- * are made available under the terms of the GNU Public License v3.0
- * which accompanies this distribution, and is available at
- * http://www.gnu.org/licenses/gpl.html
- */
-
-package at.bitfire.davdroid;
-
-import android.accounts.Account;
-import android.accounts.AccountManager;
-import android.app.Service;
-import android.content.ContentValues;
-import android.content.Intent;
-import android.database.Cursor;
-import android.database.DatabaseUtils;
-import android.database.sqlite.SQLiteDatabase;
-import android.os.Binder;
-import android.os.IBinder;
-import android.text.TextUtils;
-
-import java.io.IOException;
-import java.util.HashSet;
-import java.util.Iterator;
-import java.util.LinkedHashMap;
-import java.util.LinkedHashSet;
-import java.util.LinkedList;
-import java.util.List;
-import java.util.Map;
-import java.util.Set;
-import java.util.logging.Level;
-
-import at.bitfire.dav4android.DavResource;
-import at.bitfire.dav4android.UrlUtils;
-import at.bitfire.dav4android.exception.DavException;
-import at.bitfire.dav4android.exception.HttpException;
-import at.bitfire.dav4android.exception.NotFoundException;
-import at.bitfire.dav4android.property.AddressbookHomeSet;
-import at.bitfire.dav4android.property.CalendarHomeSet;
-import at.bitfire.dav4android.property.GroupMembership;
-import at.bitfire.davdroid.model.CollectionInfo;
-import at.bitfire.davdroid.model.ServiceDB.Collections;
-import at.bitfire.davdroid.model.ServiceDB.HomeSets;
-import at.bitfire.davdroid.model.ServiceDB.OpenHelper;
-import at.bitfire.davdroid.model.ServiceDB.Services;
-import lombok.Cleanup;
-import okhttp3.HttpUrl;
-import okhttp3.OkHttpClient;
-
-public class DavService extends Service {
-
-    public static final String
-            ACTION_ACCOUNTS_UPDATED = "accountsUpdated",
-            ACTION_REFRESH_COLLECTIONS = "refreshCollections",
-            EXTRA_DAV_SERVICE_ID = "davServiceID";
-
-    private final IBinder binder = new InfoBinder();
-
-    private final Set<Long> runningRefresh = new HashSet<>();
-    private final List<RefreshingStatusListener> refreshingStatusListeners = new LinkedList<>();
-
-
-    @Override
-    public int onStartCommand(Intent intent, int flags, int startId) {
-        String action = intent.getAction();
-        long id = intent.getLongExtra(EXTRA_DAV_SERVICE_ID, -1);
-
-        switch (action) {
-            case ACTION_ACCOUNTS_UPDATED:
-                cleanupAccounts();
-                break;
-            case ACTION_REFRESH_COLLECTIONS:
-                if (runningRefresh.add(id)) {
-                    new Thread(new RefreshCollections(id)).start();
-                    for (RefreshingStatusListener listener : refreshingStatusListeners)
-                        listener.onDavRefreshStatusChanged(id, true);
-                }
-                break;
-        }
-
-        return START_NOT_STICKY;
-    }
-
-
-    /* BOUND SERVICE PART
-       for communicating with the activities
-    */
-
-    @Override
-    public IBinder onBind(Intent intent) {
-        return binder;
-    }
-
-    public interface RefreshingStatusListener {
-        void onDavRefreshStatusChanged(long id, boolean refreshing);
-    }
-
-    public class InfoBinder extends Binder {
-        public boolean isRefreshing(long id) {
-            return runningRefresh.contains(id);
-        }
-
-        public void addRefreshingStatusListener(RefreshingStatusListener listener, boolean callImmediate) {
-            refreshingStatusListeners.add(listener);
-            if (callImmediate)
-                for (long id : runningRefresh)
-                    listener.onDavRefreshStatusChanged(id, true);
-        }
-
-        public void removeRefreshingStatusListener(RefreshingStatusListener listener) {
-            refreshingStatusListeners.remove(listener);
-        }
-    }
-
-
-    /* ACTION RUNNABLES
-       which actually do the work
-     */
-
-    void cleanupAccounts() {
-        App.log.info("Cleaning up orphaned accounts");
-
-        final OpenHelper dbHelper = new OpenHelper(this);
-        try {
-            SQLiteDatabase db = dbHelper.getWritableDatabase();
-
-            List<String> sqlAccountNames = new LinkedList<>();
-            AccountManager am = AccountManager.get(this);
-            for (Account account : am.getAccountsByType(Constants.ACCOUNT_TYPE))
-                sqlAccountNames.add(DatabaseUtils.sqlEscapeString(account.name));
-
-            if (sqlAccountNames.isEmpty())
-                db.delete(Services._TABLE, null, null);
-            else
-                db.delete(Services._TABLE, Services.ACCOUNT_NAME + " NOT IN (" + TextUtils.join(",", sqlAccountNames) + ")", null);
-        } finally {
-            dbHelper.close();
-        }
-    }
-
-    private class RefreshCollections implements Runnable {
-        final long service;
-        final OpenHelper dbHelper;
-        SQLiteDatabase db;
-
-        RefreshCollections(long davServiceId) {
-            this.service = davServiceId;
-            dbHelper = new OpenHelper(DavService.this);
-        }
-
-        @Override
-        public void run() {
-            try {
-                db = dbHelper.getWritableDatabase();
-
-                String serviceType = serviceType();
-                App.log.info("Refreshing " + serviceType + " collections of service #" + service);
-
-                // create authenticating OkHttpClient (credentials taken from account settings)
-                OkHttpClient httpClient = httpClient();
-
-                // refresh home sets: principal
-                Set<HttpUrl> homeSets = readHomeSets();
-                HttpUrl principal = readPrincipal();
-                if (principal != null) {
-                    App.log.fine("Querying principal for home sets");
-                    DavResource dav = new DavResource(httpClient, principal);
-                    queryHomeSets(serviceType, httpClient, principal, homeSets);
-
-                    // refresh home sets: direct group memberships
-                    GroupMembership groupMembership = (GroupMembership)dav.properties.get(GroupMembership.NAME);
-                    if (groupMembership != null)
-                        for (String href : groupMembership.hrefs) {
-                            App.log.fine("Querying member group " + href + " for home sets");
-                            queryHomeSets(serviceType, httpClient, dav.location.resolve(href), homeSets);
-                        }
-                }
-
-                // now refresh collections (taken from home sets)
-                Map<HttpUrl, CollectionInfo> collections = readCollections();
-
-                // (remember selections before)
-                Set<HttpUrl> selectedCollections = new HashSet<>();
-                for (CollectionInfo info : collections.values())
-                    if (info.selected)
-                        selectedCollections.add(HttpUrl.parse(info.url));
-
-                for (Iterator<HttpUrl> iterator = homeSets.iterator(); iterator.hasNext();) {
-                    HttpUrl homeSet = iterator.next();
-                    App.log.fine("Listing home set " + homeSet);
-
-                    DavResource dav = new DavResource(httpClient, homeSet);
-                    try {
-                        dav.propfind(1, CollectionInfo.DAV_PROPERTIES);
-                        for (DavResource member : dav.members) {
-                            CollectionInfo info = CollectionInfo.fromDavResource(member);
-                            info.confirmed = true;
-                            App.log.fine("Found collection" + info);
-
-                            if ((serviceType.equals(Services.SERVICE_CARDDAV) && info.type == CollectionInfo.Type.ADDRESS_BOOK) ||
-                                (serviceType.equals(Services.SERVICE_CALDAV) && info.type == CollectionInfo.Type.CALENDAR))
-                                collections.put(member.location, info);
-                        }
-                    } catch(NotFoundException e) {
-                        // 404, remove home set
-                        iterator.remove();
-                    }
-                }
-
-                // check/refresh unconfirmed collections
-                for (Iterator<Map.Entry<HttpUrl, CollectionInfo>> iterator = collections.entrySet().iterator(); iterator.hasNext();) {
-                    Map.Entry<HttpUrl, CollectionInfo> entry = iterator.next();
-                    HttpUrl url = entry.getKey();
-                    CollectionInfo info = entry.getValue();
-
-                    if (!info.confirmed)
-                        try {
-                            DavResource dav = new DavResource(httpClient, url);
-                            dav.propfind(0, CollectionInfo.DAV_PROPERTIES);
-                            info = CollectionInfo.fromDavResource(dav);
-                            info.confirmed = true;
-
-                            // remove unusable collections
-                            if ((serviceType.equals(Services.SERVICE_CARDDAV) && info.type != CollectionInfo.Type.ADDRESS_BOOK) ||
-                                (serviceType.equals(Services.SERVICE_CALDAV) && info.type != CollectionInfo.Type.CALENDAR))
-                                iterator.remove();
-                        } catch(NotFoundException e) {
-                            // 404, remove collection
-                            iterator.remove();
-                        }
-                }
-
-                // restore selections
-                for (HttpUrl url : selectedCollections) {
-                    CollectionInfo info = collections.get(url);
-                    if (info != null)
-                        info.selected = true;
-                }
-
-                try {
-                    db.beginTransaction();
-                    saveHomeSets(homeSets);
-                    saveCollections(collections.values());
-                    db.setTransactionSuccessful();
-                } finally {
-                    db.endTransaction();
-                }
-
-            } catch (IOException|HttpException|DavException e) {
-                App.log.log(Level.SEVERE, "Couldn't refresh collection list", e);
-            } finally {
-                dbHelper.close();
-
-                runningRefresh.remove(service);
-                for (RefreshingStatusListener listener : refreshingStatusListeners)
-                    listener.onDavRefreshStatusChanged(service, false);
-            }
-        }
-
-        private void queryHomeSets(String serviceType, OkHttpClient client, HttpUrl url, Set<HttpUrl> homeSets) throws IOException, HttpException, DavException {
-            DavResource dav = new DavResource(client, url);
-            if (Services.SERVICE_CARDDAV.equals(serviceType)) {
-                dav.propfind(0, AddressbookHomeSet.NAME, GroupMembership.NAME);
-                AddressbookHomeSet addressbookHomeSet = (AddressbookHomeSet)dav.properties.get(AddressbookHomeSet.NAME);
-                if (addressbookHomeSet != null)
-                    for (String href : addressbookHomeSet.hrefs)
-                        homeSets.add(UrlUtils.withTrailingSlash(dav.location.resolve(href)));
-            } else if (Services.SERVICE_CALDAV.equals(serviceType)) {
-                dav.propfind(0, CalendarHomeSet.NAME, GroupMembership.NAME);
-                CalendarHomeSet calendarHomeSet = (CalendarHomeSet)dav.properties.get(CalendarHomeSet.NAME);
-                if (calendarHomeSet != null)
-                    for (String href : calendarHomeSet.hrefs)
-                        homeSets.add(UrlUtils.withTrailingSlash(dav.location.resolve(href)));
-            }
-        }
-
-
-        private OkHttpClient httpClient() {
-            @Cleanup Cursor cursor = db.query(Services._TABLE, new String[]{Services.ACCOUNT_NAME}, Services.ID + "=?", new String[] { String.valueOf(service) }, null, null, null);
-            if (cursor.moveToNext()) {
-                Account account = new Account(cursor.getString(0), Constants.ACCOUNT_TYPE);
-                return HttpClient.create(DavService.this, account);
-            } else
-                throw new IllegalArgumentException("Service not found");
-        }
-
-        private String serviceType() {
-            @Cleanup Cursor cursor = db.query(Services._TABLE, new String[]{Services.SERVICE}, Services.ID + "=?", new String[] { String.valueOf(service) }, null, null, null);
-            if (cursor.moveToNext())
-                return cursor.getString(0);
-            else
-                throw new IllegalArgumentException("Service not found");
-        }
-
-        private HttpUrl readPrincipal() {
-            @Cleanup Cursor cursor = db.query(Services._TABLE, new String[]{Services.PRINCIPAL}, Services.ID + "=?", new String[]{String.valueOf(service)}, null, null, null);
-            if (cursor.moveToNext()) {
-                String principal = cursor.getString(0);
-                if (principal != null)
-                    return HttpUrl.parse(cursor.getString(0));
-            }
-            return null;
-        }
-
-        private Set<HttpUrl> readHomeSets() {
-            Set<HttpUrl> homeSets = new LinkedHashSet<>();
-            @Cleanup Cursor cursor = db.query(HomeSets._TABLE, new String[]{HomeSets.URL}, HomeSets.SERVICE_ID + "=?", new String[]{String.valueOf(service)}, null, null, null);
-            while (cursor.moveToNext())
-                homeSets.add(HttpUrl.parse(cursor.getString(0)));
-            return homeSets;
-        }
-
-        private void saveHomeSets(Set<HttpUrl> homeSets) {
-            db.delete(HomeSets._TABLE, HomeSets.SERVICE_ID + "=?", new String[]{String.valueOf(service)});
-            for (HttpUrl homeSet : homeSets) {
-                ContentValues values = new ContentValues(1);
-                values.put(HomeSets.SERVICE_ID, service);
-                values.put(HomeSets.URL, homeSet.toString());
-                db.insertOrThrow(HomeSets._TABLE, null, values);
-            }
-        }
-
-        private Map<HttpUrl, CollectionInfo> readCollections() {
-            Map<HttpUrl, CollectionInfo> collections = new LinkedHashMap<>();
-            @Cleanup Cursor cursor = db.query(Collections._TABLE, Collections._COLUMNS, Collections.SERVICE_ID + "=?", new String[]{String.valueOf(service)}, null, null, null);
-            while (cursor.moveToNext()) {
-                ContentValues values = new ContentValues();
-                DatabaseUtils.cursorRowToContentValues(cursor, values);
-                collections.put(HttpUrl.parse(values.getAsString(Collections.URL)), CollectionInfo.fromDB(values));
-            }
-            return collections;
-        }
-
-        private void saveCollections(Iterable<CollectionInfo> collections) {
-            db.delete(Collections._TABLE, HomeSets.SERVICE_ID + "=?", new String[]{String.valueOf(service)});
-            for (CollectionInfo collection : collections) {
-                ContentValues values = collection.toDB();
-                App.log.log(Level.FINE, "Saving collection", values);
-                values.put(Collections.SERVICE_ID, service);
-                db.insertWithOnConflict(Collections._TABLE, null, values, SQLiteDatabase.CONFLICT_REPLACE);
-            }
-        }
-    }
-
-}

app/src/main/java/at/bitfire/davdroid/DavService.kt

@@ -0,0 +1,344 @@
+/*
+ * Copyright © Ricki Hirner (bitfire web engineering).
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the GNU Public License v3.0
+ * which accompanies this distribution, and is available at
+ * http://www.gnu.org/licenses/gpl.html
+ */
+
+package at.bitfire.davdroid
+
+import android.accounts.Account
+import android.app.PendingIntent
+import android.app.Service
+import android.content.ContentValues
+import android.content.Intent
+import android.database.DatabaseUtils
+import android.database.sqlite.SQLiteDatabase
+import android.os.Binder
+import android.support.v4.app.NotificationCompat
+import at.bitfire.dav4android.DavResource
+import at.bitfire.dav4android.UrlUtils
+import at.bitfire.dav4android.exception.DavException
+import at.bitfire.dav4android.exception.HttpException
+import at.bitfire.dav4android.property.*
+import at.bitfire.davdroid.log.Logger
+import at.bitfire.davdroid.model.CollectionInfo
+import at.bitfire.davdroid.model.ServiceDB.*
+import at.bitfire.davdroid.model.ServiceDB.Collections
+import at.bitfire.davdroid.settings.Settings
+import at.bitfire.davdroid.ui.DebugInfoActivity
+import at.bitfire.davdroid.ui.NotificationUtils
+import okhttp3.HttpUrl
+import org.apache.commons.collections4.iterators.IteratorChain
+import org.apache.commons.collections4.iterators.SingletonIterator
+import java.io.IOException
+import java.lang.ref.WeakReference
+import java.util.*
+import java.util.logging.Level
+import kotlin.concurrent.thread
+
+class DavService: Service() {
+
+    companion object {
+        @JvmField val ACTION_REFRESH_COLLECTIONS = "refreshCollections"
+        @JvmField val EXTRA_DAV_SERVICE_ID = "davServiceID"
+    }
+
+    private val runningRefresh = HashSet<Long>()
+    private val refreshingStatusListeners = LinkedList<WeakReference<RefreshingStatusListener>>()
+
+
+    override fun onStartCommand(intent: Intent?, flags: Int, startId: Int): Int {
+        intent?.let {
+            val id = intent.getLongExtra(EXTRA_DAV_SERVICE_ID, -1)
+
+            when (intent.action) {
+                ACTION_REFRESH_COLLECTIONS ->
+                    if (runningRefresh.add(id)) {
+                        thread { refreshCollections(id) }
+                        refreshingStatusListeners.forEach { it.get()?.onDavRefreshStatusChanged(id, true) }
+                    }
+            }
+        }
+
+        return START_NOT_STICKY
+    }
+
+
+    /* BOUND SERVICE PART
+       for communicating with the activities
+    */
+
+    interface RefreshingStatusListener {
+        fun onDavRefreshStatusChanged(id: Long, refreshing: Boolean)
+    }
+
+    private val binder = InfoBinder()
+
+    inner class InfoBinder: Binder() {
+        fun isRefreshing(id: Long) = runningRefresh.contains(id)
+
+        fun addRefreshingStatusListener(listener: RefreshingStatusListener, callImmediate: Boolean) {
+            refreshingStatusListeners += WeakReference<RefreshingStatusListener>(listener)
+            if (callImmediate)
+                runningRefresh.forEach { id -> listener.onDavRefreshStatusChanged(id, true) }
+        }
+
+        fun removeRefreshingStatusListener(listener: RefreshingStatusListener) {
+            val iter = refreshingStatusListeners.iterator()
+            while (iter.hasNext()) {
+                val item = iter.next().get()
+                if (listener == item)
+                    iter.remove()
+            }
+        }
+    }
+
+    override fun onBind(intent: Intent?) = binder
+
+
+
+    /* ACTION RUNNABLES
+       which actually do the work
+     */
+
+    private fun refreshCollections(service: Long) {
+        OpenHelper(this@DavService).use { dbHelper ->
+            val db = dbHelper.writableDatabase
+
+            val serviceType by lazy {
+                db.query(Services._TABLE, arrayOf(Services.SERVICE), "${Services.ID}=?", arrayOf(service.toString()), null, null, null)?.use { cursor ->
+                    if (cursor.moveToNext())
+                        return@lazy cursor.getString(0)
+                } ?: throw IllegalArgumentException("Service not found")
+            }
+
+            val account by lazy {
+                db.query(Services._TABLE, arrayOf(Services.ACCOUNT_NAME), "${Services.ID}=?", arrayOf(service.toString()), null, null, null)?.use { cursor ->
+                    if (cursor.moveToNext())
+                        return@lazy Account(cursor.getString(0), getString(R.string.account_type))
+                }
+                throw IllegalArgumentException("Account not found")
+            }
+
+            val homeSets by lazy {
+                val homeSets = mutableSetOf<HttpUrl>()
+                db.query(HomeSets._TABLE, arrayOf(HomeSets.URL), "${HomeSets.SERVICE_ID}=?", arrayOf(service.toString()), null, null, null)?.use { cursor ->
+                    while (cursor.moveToNext())
+                        HttpUrl.parse(cursor.getString(0))?.let { homeSets += it }
+                }
+                homeSets
+            }
+
+            val collections by lazy {
+                val collections = mutableMapOf<HttpUrl, CollectionInfo>()
+                db.query(Collections._TABLE, null, "${Collections.SERVICE_ID}=?", arrayOf(service.toString()), null, null, null)?.use { cursor ->
+                    while (cursor.moveToNext()) {
+                        val values = ContentValues()
+                        DatabaseUtils.cursorRowToContentValues(cursor, values)
+                        values.getAsString(Collections.URL)?.let { url ->
+                            HttpUrl.parse(url)?.let { collections.put(it, CollectionInfo(values)) }
+                        }
+                    }
+                }
+                collections
+            }
+
+            fun readPrincipal(): HttpUrl? {
+                db.query(Services._TABLE, arrayOf(Services.PRINCIPAL), "${Services.ID}=?", arrayOf(service.toString()), null, null, null)?.use { cursor ->
+                    if (cursor.moveToNext())
+                        cursor.getString(0)?.let { return HttpUrl.parse(it) }
+                }
+                return null
+            }
+
+            /**
+             * Checks if the given URL defines home sets and adds them to the home set list.
+             * @param dav               DavResource to check
+             */
+            @Throws(IOException::class, HttpException::class, DavException::class)
+            fun queryHomeSets(dav: DavResource) {
+                when (serviceType) {
+                    Services.SERVICE_CARDDAV -> {
+                        dav.propfind(0, AddressbookHomeSet.NAME, GroupMembership.NAME)
+                        for ((resource, addressbookHomeSet) in dav.findProperties(AddressbookHomeSet::class.java))
+                            for (href in addressbookHomeSet.hrefs)
+                                resource.location.resolve(href)?.let { homeSets += UrlUtils.withTrailingSlash(it) }
+                    }
+                    Services.SERVICE_CALDAV -> {
+                        dav.propfind(0, CalendarHomeSet.NAME, CalendarProxyReadFor.NAME, CalendarProxyWriteFor.NAME, GroupMembership.NAME)
+                        for ((resource, calendarHomeSet) in dav.findProperties(CalendarHomeSet::class.java))
+                            for (href in calendarHomeSet.hrefs)
+                                resource.location.resolve(href)?.let { homeSets.add(UrlUtils.withTrailingSlash(it)) }
+                    }
+                }
+            }
+
+            fun saveHomeSets() {
+                db.delete(HomeSets._TABLE, "${HomeSets.SERVICE_ID}=?", arrayOf(service.toString()))
+                for (homeSet in homeSets) {
+                    val values = ContentValues(2)
+                    values.put(HomeSets.SERVICE_ID, service)
+                    values.put(HomeSets.URL, homeSet.toString())
+                    db.insertOrThrow(HomeSets._TABLE, null, values)
+                }
+            }
+
+            fun saveCollections() {
+                db.delete(Collections._TABLE, "${HomeSets.SERVICE_ID}=?", arrayOf(service.toString()))
+                for ((_,collection) in collections) {
+                    val values = collection.toDB()
+                    Logger.log.log(Level.FINE, "Saving collection", values)
+                    values.put(Collections.SERVICE_ID, service)
+                    db.insertWithOnConflict(Collections._TABLE, null, values, SQLiteDatabase.CONFLICT_REPLACE)
+                }
+            }
+
+
+            try {
+                Logger.log.info("Refreshing $serviceType collections of service #$service")
+
+                Settings.getInstance(this)?.use { settings ->
+                    // create authenticating OkHttpClient (credentials taken from account settings)
+                    HttpClient.Builder(this, settings, AccountSettings(this, settings, account))
+                            .setForeground(true)
+                            .build().use { client ->
+                        val httpClient = client.okHttpClient
+
+                        // refresh home set list (from principal)
+                        readPrincipal()?.let { principalUrl ->
+                            Logger.log.fine("Querying principal $principalUrl for home sets")
+                            val principal = DavResource(httpClient, principalUrl)
+                            queryHomeSets(principal)
+
+                            // refresh home sets: calendar-proxy-read/write-for
+                            for ((resource, proxyRead) in principal.findProperties(CalendarProxyReadFor::class.java))
+                                for (href in proxyRead.hrefs) {
+                                    Logger.log.fine("Principal is a read-only proxy for $href, checking for home sets")
+                                    resource.location.resolve(href)?.let { queryHomeSets(DavResource(httpClient, it)) }
+                                }
+                            for ((resource, proxyWrite) in principal.findProperties(CalendarProxyWriteFor::class.java))
+                                for (href in proxyWrite.hrefs) {
+                                    Logger.log.fine("Principal is a read/write proxy for $href, checking for home sets")
+                                    resource.location.resolve(href)?.let { queryHomeSets(DavResource(httpClient, it)) }
+                                }
+
+                            // refresh home sets: direct group memberships
+                            principal.properties[GroupMembership::class.java]?.let { groupMembership ->
+                                for (href in groupMembership.hrefs) {
+                                    Logger.log.fine("Principal is member of group $href, checking for home sets")
+                                    principal.location.resolve(href)?.let { url ->
+                                        try {
+                                            queryHomeSets(DavResource(httpClient, url))
+                                        } catch(e: HttpException) {
+                                            Logger.log.log(Level.WARNING, "Couldn't query member group", e)
+                                        } catch(e: DavException) {
+                                            Logger.log.log(Level.WARNING, "Couldn't query member group", e)
+                                        }
+                                    }
+                                }
+                            }
+                        }
+
+                        // remember selected collections
+                        val selectedCollections = HashSet<HttpUrl>()
+                        collections.values
+                                .filter { it.selected }
+                                .forEach { (url,_) -> HttpUrl.parse(url)?.let { selectedCollections.add(it) } }
+
+                        // now refresh collections (taken from home sets)
+                        val itHomeSets = homeSets.iterator()
+                        while (itHomeSets.hasNext()) {
+                            val homeSetUrl = itHomeSets.next()
+                            Logger.log.fine("Listing home set $homeSetUrl")
+
+                            val homeSet = DavResource(httpClient, homeSetUrl)
+                            try {
+                                homeSet.propfind(1, *CollectionInfo.DAV_PROPERTIES)
+                                val itCollections = IteratorChain<DavResource>(homeSet.members.iterator(), homeSet.related.iterator(), SingletonIterator(homeSet))
+                                while (itCollections.hasNext()) {
+                                    val member = itCollections.next()
+                                    val info = CollectionInfo(member)
+                                    info.confirmed = true
+                                    Logger.log.log(Level.FINE, "Found collection", info)
+
+                                    if ((serviceType == Services.SERVICE_CARDDAV && info.type == CollectionInfo.Type.ADDRESS_BOOK) ||
+                                            (serviceType == Services.SERVICE_CALDAV && arrayOf(CollectionInfo.Type.CALENDAR, CollectionInfo.Type.WEBCAL).contains(info.type)))
+                                        collections[member.location] = info
+                                }
+                            } catch(e: HttpException) {
+                                if (e.status in arrayOf(403, 404, 410))
+                                // delete home set only if it was not accessible (40x)
+                                    itHomeSets.remove()
+                            }
+                        }
+
+                        // check/refresh unconfirmed collections
+                        val itCollections = collections.entries.iterator()
+                        while (itCollections.hasNext()) {
+                            val (url, info) = itCollections.next()
+                            if (!info.confirmed)
+                                try {
+                                    val collection = DavResource(httpClient, url)
+                                    collection.propfind(0, *CollectionInfo.DAV_PROPERTIES)
+                                    val info = CollectionInfo(collection)
+                                    info.confirmed = true
+
+                                    // remove unusable collections
+                                    if ((serviceType == Services.SERVICE_CARDDAV && info.type != CollectionInfo.Type.ADDRESS_BOOK) ||
+                                            (serviceType == Services.SERVICE_CALDAV && !arrayOf(CollectionInfo.Type.CALENDAR, CollectionInfo.Type.WEBCAL).contains(info.type)) ||
+                                            (info.type == CollectionInfo.Type.WEBCAL && info.source == null))
+                                        itCollections.remove()
+                                } catch(e: HttpException) {
+                                    if (e.status in arrayOf(403, 404, 410))
+                                    // delete collection only if it was not accessible (40x)
+                                        itCollections.remove()
+                                    else
+                                        throw e
+                                }
+                        }
+
+                        // restore selections
+                        for (url in selectedCollections)
+                            collections[url]?.let { it.selected = true }
+                    }
+
+                }
+
+                db.beginTransactionNonExclusive()
+                try {
+                    saveHomeSets()
+                    saveCollections()
+                    db.setTransactionSuccessful()
+                } finally {
+                    db.endTransaction()
+                }
+
+            } catch(e: InvalidAccountException) {
+                Logger.log.log(Level.SEVERE, "Invalid account", e)
+            } catch(e: Exception) {
+                Logger.log.log(Level.SEVERE, "Couldn't refresh collection list", e)
+
+                val debugIntent = Intent(this@DavService, DebugInfoActivity::class.java)
+                debugIntent.putExtra(DebugInfoActivity.KEY_THROWABLE, e)
+                debugIntent.putExtra(DebugInfoActivity.KEY_ACCOUNT, account)
+
+                val nm = NotificationUtils.createChannels(this)
+                val notify = NotificationCompat.Builder(this, NotificationUtils.CHANNEL_SYNC_PROBLEMS)
+                        .setSmallIcon(R.drawable.ic_sync_error_notification)
+                        .setLargeIcon(App.getLauncherBitmap(this))
+                        .setContentTitle(getString(R.string.dav_service_refresh_failed))
+                        .setContentText(getString(R.string.dav_service_refresh_couldnt_refresh))
+                        .setContentIntent(PendingIntent.getActivity(this, 0, debugIntent, PendingIntent.FLAG_UPDATE_CURRENT))
+                        .build()
+                nm.notify(Constants.NOTIFICATION_REFRESH_COLLECTIONS, notify)
+            } finally {
+                runningRefresh.remove(service)
+                refreshingStatusListeners.forEach { it.get()?.onDavRefreshStatusChanged(service, false) }
+            }
+        }
+
+    }
+
+}

app/src/main/java/at/bitfire/davdroid/DavUtils.java

@@ -1,22 +0,0 @@
-/*
- * Copyright © 2013 – 2015 Ricki Hirner (bitfire web engineering).
- * All rights reserved. This program and the accompanying materials
- * are made available under the terms of the GNU Public License v3.0
- * which accompanies this distribution, and is available at
- * http://www.gnu.org/licenses/gpl.html
- */
-
-package at.bitfire.davdroid;
-
-import java.util.regex.Matcher;
-import java.util.regex.Pattern;
-
-public class DavUtils {
-
-    public static String ARGBtoCalDAVColor(int colorWithAlpha) {
-        byte alpha = (byte)(colorWithAlpha >> 24);
-        int color = colorWithAlpha & 0xFFFFFF;
-        return String.format("#%06X%02X", color, alpha);
-    }
-
-}

app/src/main/java/at/bitfire/davdroid/DavUtils.kt

@@ -0,0 +1,86 @@
+/*
+ * Copyright © Ricki Hirner (bitfire web engineering).
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the GNU Public License v3.0
+ * which accompanies this distribution, and is available at
+ * http://www.gnu.org/licenses/gpl.html
+ */
+
+package at.bitfire.davdroid
+
+import android.annotation.TargetApi
+import android.content.Context
+import android.net.ConnectivityManager
+import android.os.Build
+import at.bitfire.davdroid.log.Logger
+import okhttp3.HttpUrl
+import org.xbill.DNS.*
+import java.util.*
+
+/**
+ * Some WebDAV and related network utility methods
+ */
+object DavUtils {
+
+    @JvmStatic
+    fun ARGBtoCalDAVColor(colorWithAlpha: Int): String {
+        val alpha = (colorWithAlpha shr 24) and 0xFF
+        val color = colorWithAlpha and 0xFFFFFF
+        return String.format("#%06X%02X", color, alpha)
+    }
+
+    @JvmStatic
+    fun lastSegmentOfUrl(url: String): String {
+        val httpUrl = HttpUrl.parse(url) ?: throw IllegalArgumentException("url not parsable")
+
+        // the list returned by HttpUrl.pathSegments() is unmodifiable, so we have to create a copy
+        val segments = LinkedList<String>(httpUrl.pathSegments())
+        Collections.reverse(segments)
+
+        return segments.firstOrNull { it.isNotEmpty() } ?: "/"
+    }
+
+    fun prepareLookup(context: Context, lookup: Lookup) {
+        @TargetApi(Build.VERSION_CODES.O)
+        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
+            /* Since Android 8, the system properties net.dns1, net.dns2, ... are not available anymore.
+               The current version of dnsjava relies on these properties to find the default name servers,
+               so we have to add the servers explicitly (fortunately, there's an Android API to
+               get the active DNS servers). */
+            val connectivity = context.getSystemService(Context.CONNECTIVITY_SERVICE) as ConnectivityManager
+            val activeLink = connectivity.getLinkProperties(connectivity.activeNetwork)
+            val simpleResolvers = activeLink.dnsServers.map {
+                Logger.log.fine("Using DNS server ${it.hostAddress}")
+                val resolver = SimpleResolver()
+                resolver.setAddress(it)
+                resolver
+            }
+            val resolver = ExtendedResolver(simpleResolvers.toTypedArray())
+            lookup.setResolver(resolver)
+        }
+    }
+
+    fun selectSRVRecord(records: Array<Record>?): SRVRecord? {
+        val srvRecords = records?.filterIsInstance(SRVRecord::class.java)
+        srvRecords?.let {
+            if (it.size > 1)
+                Logger.log.warning("Multiple SRV records not supported yet; using first one")
+            return it.firstOrNull()
+        }
+        return null
+    }
+
+    fun pathsFromTXTRecords(records: Array<Record>?): List<String> {
+        val paths = LinkedList<String>()
+        records?.filterIsInstance(TXTRecord::class.java)?.forEach { txt ->
+            @Suppress("UNCHECKED_CAST")
+            for (segment in txt.strings as List<String>)
+                if (segment.startsWith("path=")) {
+                    paths.add(segment.substring(5))
+                    break
+                }
+        }
+        return paths
+    }
+
+}

app/src/main/java/at/bitfire/davdroid/HttpClient.java

@@ -1,143 +0,0 @@
-/*
- * Copyright © 2013 – 2015 Ricki Hirner (bitfire web engineering).
- * All rights reserved. This program and the accompanying materials
- * are made available under the terms of the GNU Public License v3.0
- * which accompanies this distribution, and is available at
- * http://www.gnu.org/licenses/gpl.html
- */
-
-package at.bitfire.davdroid;
-
-import android.accounts.Account;
-import android.content.Context;
-import android.os.Build;
-import android.support.annotation.NonNull;
-
-import java.io.IOException;
-import java.text.SimpleDateFormat;
-import java.util.Date;
-import java.util.Locale;
-import java.util.concurrent.TimeUnit;
-import java.util.logging.Level;
-import java.util.logging.Logger;
-
-import at.bitfire.dav4android.BasicDigestAuthenticator;
-import lombok.RequiredArgsConstructor;
-import okhttp3.Credentials;
-import okhttp3.Interceptor;
-import okhttp3.OkHttpClient;
-import okhttp3.Request;
-import okhttp3.Response;
-import okhttp3.logging.HttpLoggingInterceptor;
-
-public class HttpClient {
-    private static final OkHttpClient client = new OkHttpClient();
-    private static final UserAgentInterceptor userAgentInterceptor = new UserAgentInterceptor();
-
-    private static final String userAgent;
-    static {
-        String date = new SimpleDateFormat("yyyy/MM/dd", Locale.US).format(new Date(BuildConfig.buildTime));
-        userAgent = "DAVdroid/" + BuildConfig.VERSION_NAME + " (" + date + "; dav4android; okhttp3) Android/" + Build.VERSION.RELEASE;
-    }
-
-    private HttpClient() {
-    }
-
-    public static OkHttpClient create(Context context, Account account, @NonNull final Logger logger) {
-        OkHttpClient.Builder builder = client.newBuilder();
-
-        // use MemorizingTrustManager to manage self-signed certificates
-        if (App.getSslSocketFactoryCompat() != null)
-            builder.sslSocketFactory(App.getSslSocketFactoryCompat());
-        if (App.getHostnameVerifier() != null)
-            builder.hostnameVerifier(App.getHostnameVerifier());
-
-        // set timeouts
-        builder.connectTimeout(30, TimeUnit.SECONDS);
-        builder.writeTimeout(30, TimeUnit.SECONDS);
-        builder.readTimeout(120, TimeUnit.SECONDS);
-
-        // don't allow redirects, because it would break PROPFIND handling
-        builder.followRedirects(false);
-
-        // add User-Agent to every request
-        builder.addNetworkInterceptor(userAgentInterceptor);
-
-        // add cookie store for non-persistent cookies (some services like Horde use cookies for session tracking)
-        builder.cookieJar(MemoryCookieStore.INSTANCE);
-
-        if (context != null && account != null) {
-            // use account settings for authentication and logging
-            AccountSettings settings = new AccountSettings(context, account);
-
-            if (settings.preemptiveAuth())
-                builder.addNetworkInterceptor(new PreemptiveAuthenticationInterceptor(settings.username(), settings.password()));
-            else
-                builder.authenticator(new BasicDigestAuthenticator(null, settings.username(), settings.password()));
-        }
-
-        if (logger.isLoggable(Level.FINEST)) {
-            HttpLoggingInterceptor loggingInterceptor = new HttpLoggingInterceptor(new HttpLoggingInterceptor.Logger() {
-                @Override
-                public void log(String message) {
-                    logger.finest(message);
-                }
-            });
-            loggingInterceptor.setLevel(HttpLoggingInterceptor.Level.BODY);
-            builder.addInterceptor(loggingInterceptor);
-        }
-
-        return builder.build();
-    }
-
-    public static OkHttpClient create(Context context, Account account) {
-        return create(context, account, App.log);
-    }
-
-    private static OkHttpClient.Builder addAuthentication(@NonNull OkHttpClient.Builder builder, @NonNull String username, @NonNull String password, boolean preemptive) {
-        if (preemptive)
-            builder.addNetworkInterceptor(new PreemptiveAuthenticationInterceptor(username, password));
-        else
-            builder.authenticator(new BasicDigestAuthenticator(null, username, password));
-        return builder;
-    }
-
-    public static OkHttpClient addAuthentication(@NonNull OkHttpClient client, @NonNull String username, @NonNull String password, boolean preemptive) {
-        OkHttpClient.Builder builder = client.newBuilder();
-        addAuthentication(builder, username, password, preemptive);
-        return builder.build();
-    }
-
-    public static OkHttpClient addAuthentication(@NonNull OkHttpClient client, @NonNull String host, @NonNull String username, @NonNull String password) {
-        return client.newBuilder()
-                .authenticator(new BasicDigestAuthenticator(host, username, password))
-                .build();
-    }
-
-
-    static class UserAgentInterceptor implements Interceptor {
-        @Override
-        public Response intercept(Chain chain) throws IOException {
-            Locale locale = Locale.getDefault();
-            Request request = chain.request().newBuilder()
-                    .header("User-Agent", userAgent)
-                    .header("Accept-Language", locale.getLanguage() + "-" + locale.getCountry() + ", " + locale.getLanguage() + ";q=0.7, *;q=0.5")
-                    .build();
-            return chain.proceed(request);
-        }
-    }
-
-    @RequiredArgsConstructor
-    static class PreemptiveAuthenticationInterceptor implements Interceptor {
-        final String username, password;
-
-        @Override
-        public Response intercept(Chain chain) throws IOException {
-            Request request = chain.request().newBuilder()
-                    .header("Authorization", Credentials.basic(username, password))
-                    .build();
-            return chain.proceed(request);
-        }
-    }
-
-}

app/src/main/java/at/bitfire/davdroid/HttpClient.kt

@@ -0,0 +1,235 @@
+/*
+ * Copyright © Ricki Hirner (bitfire web engineering).
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the GNU Public License v3.0
+ * which accompanies this distribution, and is available at
+ * http://www.gnu.org/licenses/gpl.html
+ */
+
+package at.bitfire.davdroid
+
+import android.content.Context
+import android.os.Build
+import android.security.KeyChain
+import at.bitfire.cert4android.CustomCertManager
+import at.bitfire.dav4android.BasicDigestAuthHandler
+import at.bitfire.dav4android.UrlUtils
+import at.bitfire.davdroid.log.Logger
+import at.bitfire.davdroid.model.Credentials
+import at.bitfire.davdroid.settings.ISettings
+import okhttp3.Cache
+import okhttp3.Interceptor
+import okhttp3.OkHttpClient
+import okhttp3.Response
+import okhttp3.internal.tls.OkHostnameVerifier
+import okhttp3.logging.HttpLoggingInterceptor
+import java.io.Closeable
+import java.io.File
+import java.net.InetSocketAddress
+import java.net.Proxy
+import java.net.Socket
+import java.security.KeyStore
+import java.security.Principal
+import java.text.DateFormat
+import java.util.*
+import java.util.concurrent.TimeUnit
+import java.util.logging.Level
+import javax.net.ssl.KeyManager
+import javax.net.ssl.TrustManagerFactory
+import javax.net.ssl.X509ExtendedKeyManager
+import javax.net.ssl.X509TrustManager
+
+class HttpClient private constructor(
+        val okHttpClient: OkHttpClient,
+        private val certManager: CustomCertManager?
+): Closeable {
+
+    companion object {
+        /** [OkHttpClient] singleton to build all clients from */
+        val sharedClient = OkHttpClient.Builder()
+                // set timeouts
+                .connectTimeout(30, TimeUnit.SECONDS)
+                .writeTimeout(30, TimeUnit.SECONDS)
+                .readTimeout(120, TimeUnit.SECONDS)
+
+                // don't allow redirects by default, because it would break PROPFIND handling
+                .followRedirects(false)
+
+                // add User-Agent to every request
+                .addNetworkInterceptor(UserAgentInterceptor)
+
+                .build()!!
+    }
+
+    override fun close() {
+        certManager?.close()
+    }
+
+    class Builder @JvmOverloads constructor(
+            val context: Context? = null,
+            val settings: ISettings? = null,
+            accountSettings: AccountSettings? = null,
+            val logger: java.util.logging.Logger = Logger.log
+    ) {
+        private var certManager: CustomCertManager? = null
+        private var certificateAlias: String? = null
+
+        private val orig = sharedClient.newBuilder()
+
+        init {
+            // add cookie store for non-persistent cookies (some services like Horde use cookies for session tracking)
+            orig.cookieJar(MemoryCookieStore())
+
+            // add network logging, if requested
+            if (logger.isLoggable(Level.FINEST)) {
+                val loggingInterceptor = HttpLoggingInterceptor(HttpLoggingInterceptor.Logger {
+                    message -> logger.finest(message)
+                })
+                loggingInterceptor.level = HttpLoggingInterceptor.Level.BODY
+                orig.addInterceptor(loggingInterceptor)
+            }
+
+            settings?.let {
+                // custom proxy support
+                try {
+                    if (settings.getBoolean(App.OVERRIDE_PROXY, false)) {
+                        val address = InetSocketAddress(
+                                settings.getString(App.OVERRIDE_PROXY_HOST, App.OVERRIDE_PROXY_HOST_DEFAULT),
+                                settings.getInt(App.OVERRIDE_PROXY_PORT, App.OVERRIDE_PROXY_PORT_DEFAULT)
+                        )
+
+                        val proxy = Proxy(Proxy.Type.HTTP, address)
+                        orig.proxy(proxy)
+                        Logger.log.log(Level.INFO, "Using proxy", proxy)
+                    }
+                } catch(e: Exception) {
+                    Logger.log.log(Level.SEVERE, "Can't set proxy, ignoring", e)
+                }
+
+                context?.let {
+                    if (BuildConfig.customCerts)
+                        customCertManager(CustomCertManager(context, BuildConfig.customCertsUI, !settings.getBoolean(App.DISTRUST_SYSTEM_CERTIFICATES, false)))
+
+                    // use account settings for authentication
+                    accountSettings?.let {
+                        addAuthentication(null, it.credentials())
+                    }
+                }
+            }
+        }
+
+        constructor(context: Context, host: String?, credentials: Credentials): this(context) {
+            addAuthentication(host, credentials)
+        }
+
+        fun withDiskCache(): Builder {
+            val context = context ?: throw IllegalArgumentException("Context is required to find the cache directory")
+            for (dir in arrayOf(context.externalCacheDir, context.cacheDir)) {
+                if (dir.exists() && dir.canWrite()) {
+                    val cacheDir = File(dir, "HttpClient")
+                    cacheDir.mkdir()
+                    Logger.log.fine("Using disk cache: $cacheDir")
+                    orig.cache(Cache(cacheDir, 10*1024*1024))
+                    break
+                }
+            }
+            return this
+        }
+
+        fun followRedirects(follow: Boolean): Builder {
+            orig.followRedirects(follow)
+            return this
+        }
+
+        fun customCertManager(manager: CustomCertManager) {
+            certManager = manager
+        }
+        fun setForeground(foreground: Boolean): Builder {
+            certManager?.appInForeground = foreground
+            return this
+        }
+
+        fun addAuthentication(host: String?, credentials: Credentials): Builder {
+            when (credentials.type) {
+                Credentials.Type.UsernamePassword -> {
+                    val authHandler = BasicDigestAuthHandler(UrlUtils.hostToDomain(host), credentials.userName!!, credentials.password!!)
+                    orig    .addNetworkInterceptor(authHandler)
+                            .authenticator(authHandler)
+                }
+                Credentials.Type.ClientCertificate -> {
+                    certificateAlias = credentials.certificateAlias
+                }
+            }
+            return this
+        }
+
+        fun build(): HttpClient {
+            val trustManager = certManager ?: {
+                val factory = TrustManagerFactory.getInstance(TrustManagerFactory.getDefaultAlgorithm())
+                factory.init(null as KeyStore?)
+                factory.trustManagers.first() as X509TrustManager
+            }()
+
+            val hostnameVerifier = certManager?.hostnameVerifier(OkHostnameVerifier.INSTANCE)
+                    ?: OkHostnameVerifier.INSTANCE
+
+            var keyManager: KeyManager? = null
+            try {
+                certificateAlias?.let { alias ->
+                    // get client certificate and private key
+                    val certs = KeyChain.getCertificateChain(context, alias) ?: return@let
+                    val key = KeyChain.getPrivateKey(context, alias) ?: return@let
+                    logger.fine("Using client certificate $alias for authentication (chain length: ${certs.size})")
+
+                    // create Android KeyStore (performs key operations without revealing secret data to DAVdroid)
+                    val keyStore = KeyStore.getInstance("AndroidKeyStore")
+                    keyStore.load(null)
+
+                    // create KeyManager
+                    keyManager = object: X509ExtendedKeyManager() {
+                        override fun getServerAliases(p0: String?, p1: Array<out Principal>?): Array<String>? = null
+                        override fun chooseServerAlias(p0: String?, p1: Array<out Principal>?, p2: Socket?) = null
+
+                        override fun getClientAliases(p0: String?, p1: Array<out Principal>?) =
+                                arrayOf(alias)
+
+                        override fun chooseClientAlias(p0: Array<out String>?, p1: Array<out Principal>?, p2: Socket?) =
+                                alias
+
+                        override fun getCertificateChain(forAlias: String?) =
+                                certs.takeIf { forAlias == alias }
+
+                        override fun getPrivateKey(forAlias: String?) =
+                                key.takeIf { forAlias == alias }
+                    }
+                }
+            } catch (e: Exception) {
+                logger.log(Level.SEVERE, "Couldn't set up client certificate authentication", e)
+            }
+
+            orig.sslSocketFactory(CustomTlsSocketFactory(keyManager, trustManager), trustManager)
+            orig.hostnameVerifier(hostnameVerifier)
+
+            return HttpClient(orig.build(), certManager)
+        }
+
+    }
+
+
+    private object UserAgentInterceptor: Interceptor {
+
+        private val userAgentDate = DateFormat.getDateInstance(DateFormat.SHORT, Locale.US).format(Date(BuildConfig.buildTime))
+        private val userAgent = "DAVdroid/${BuildConfig.VERSION_NAME} ($userAgentDate; dav4android; okhttp3) Android/${Build.VERSION.RELEASE}"
+
+        override fun intercept(chain: Interceptor.Chain): Response {
+            val locale = Locale.getDefault()
+            val request = chain.request().newBuilder()
+                    .header("User-Agent", userAgent)
+                    .header("Accept-Language", "${locale.language}-${locale.country}, ${locale.language};q=0.7, *;q=0.5")
+                    .build()
+            return chain.proceed(request)
+        }
+
+    }
+
+}

app/src/main/java/at/bitfire/davdroid/InvalidAccountException.kt

@@ -0,0 +1,13 @@
+/*
+ * Copyright © Ricki Hirner (bitfire web engineering).
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the GNU Public License v3.0
+ * which accompanies this distribution, and is available at
+ * http://www.gnu.org/licenses/gpl.html
+ */
+
+package at.bitfire.davdroid
+
+import android.accounts.Account
+
+class InvalidAccountException(account: Account): Exception("Invalid account: $account")

app/src/main/java/at/bitfire/davdroid/MemoryCookieStore.java

@@ -1,46 +0,0 @@
-/*
- * Copyright © 2013 – 2016 Ricki Hirner (bitfire web engineering).
- * All rights reserved. This program and the accompanying materials
- * are made available under the terms of the GNU Public License v3.0
- * which accompanies this distribution, and is available at
- * http://www.gnu.org/licenses/gpl.html
- */
-
-package at.bitfire.davdroid;
-
-import java.util.Collections;
-import java.util.List;
-import java.util.Map;
-import java.util.concurrent.ConcurrentHashMap;
-
-import okhttp3.Cookie;
-import okhttp3.CookieJar;
-import okhttp3.HttpUrl;
-
-/**
- * Primitive cookie store that stores cookies in a (volatile) hash map.
- * Will be sufficient for session cookies.
- */
-public class MemoryCookieStore implements CookieJar {
-
-    public static final MemoryCookieStore INSTANCE = new MemoryCookieStore();
-
-    protected final Map<HttpUrl, List<Cookie>> store = new ConcurrentHashMap<>();
-
-
-    @Override
-    public void saveFromResponse(HttpUrl url, List<Cookie> cookies) {
-        store.put(url, cookies);
-    }
-
-    @Override
-    public List<Cookie> loadForRequest(HttpUrl url) {
-        List<Cookie> cookies = store.get(url);
-
-        if (cookies == null)
-            cookies = Collections.emptyList();
-
-        return cookies;
-    }
-
-}

app/src/main/java/at/bitfire/davdroid/MemoryCookieStore.kt

@@ -0,0 +1,63 @@
+/*
+ * Copyright © Ricki Hirner (bitfire web engineering).
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the GNU Public License v3.0
+ * which accompanies this distribution, and is available at
+ * http://www.gnu.org/licenses/gpl.html
+ */
+
+package at.bitfire.davdroid
+
+import okhttp3.Cookie
+import okhttp3.CookieJar
+import okhttp3.HttpUrl
+import org.apache.commons.collections4.keyvalue.MultiKey
+import org.apache.commons.collections4.map.HashedMap
+import org.apache.commons.collections4.map.MultiKeyMap
+import java.util.*
+
+/**
+ * Primitive cookie store that stores cookies in a (volatile) hash map.
+ * Will be sufficient for session cookies.
+ */
+class MemoryCookieStore: CookieJar {
+
+    /**
+     * Stored cookies. The multi-key consists of three parts: name, domain, and path.
+     * This ensures that cookies can be overwritten. [RFC 6265 5.3 Storage Model]
+     * Not thread-safe!
+     */
+    val storage = MultiKeyMap.multiKeyMap(HashedMap<MultiKey<out String>, Cookie>())!!
+
+    override fun saveFromResponse(url: HttpUrl, cookies: List<Cookie>) {
+        synchronized(storage) {
+            for (cookie in cookies)
+                storage.put(cookie.name(), cookie.domain(), cookie.path(), cookie)
+        }
+    }
+
+    override fun loadForRequest(url: HttpUrl): List<Cookie> {
+        val cookies = LinkedList<Cookie>()
+
+        synchronized(storage) {
+            val iter = storage.mapIterator()
+            while (iter.hasNext()) {
+                iter.next()
+                val cookie = iter.value
+
+                // remove expired cookies
+                if (cookie.expiresAt() <= System.currentTimeMillis()) {
+                    iter.remove()
+                    continue
+                }
+
+                // add applicable cookies
+                if (cookie.matches(url))
+                    cookies += cookie
+            }
+        }
+
+        return cookies
+    }
+
+}

app/src/main/java/at/bitfire/davdroid/PackageChangedReceiver.kt

@@ -0,0 +1,65 @@
+/*
+ * Copyright © Ricki Hirner (bitfire web engineering).
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the GNU Public License v3.0
+ * which accompanies this distribution, and is available at
+ * http://www.gnu.org/licenses/gpl.html
+ */
+
+package at.bitfire.davdroid
+
+import android.accounts.Account
+import android.annotation.SuppressLint
+import android.content.BroadcastReceiver
+import android.content.ContentResolver
+import android.content.Context
+import android.content.Intent
+import android.os.Bundle
+import at.bitfire.davdroid.log.Logger
+import at.bitfire.davdroid.model.ServiceDB
+import at.bitfire.davdroid.model.ServiceDB.Services
+import at.bitfire.davdroid.resource.LocalTaskList
+import at.bitfire.ical4android.TaskProvider
+
+class PackageChangedReceiver: BroadcastReceiver() {
+
+    @SuppressLint("MissingPermission")
+    override fun onReceive(context: Context, intent: Intent) {
+        if (intent.action == Intent.ACTION_PACKAGE_ADDED || intent.action == Intent.ACTION_PACKAGE_FULLY_REMOVED)
+            updateTaskSync(context)
+    }
+
+
+    companion object {
+
+        @JvmStatic
+        fun updateTaskSync(context: Context) {
+            val tasksInstalled = LocalTaskList.tasksProviderAvailable(context)
+            Logger.log.info("Package (un)installed; OpenTasks provider now available = $tasksInstalled")
+
+            // check all accounts and (de)activate OpenTasks if a CalDAV service is defined
+            ServiceDB.OpenHelper(context).use { dbHelper ->
+                val db = dbHelper.readableDatabase
+
+                db.query(Services._TABLE, arrayOf(Services.ACCOUNT_NAME),
+                        "${Services.SERVICE}=?", arrayOf(Services.SERVICE_CALDAV), null, null, null)?.use { cursor ->
+                    while (cursor.moveToNext()) {
+                        val account = Account(cursor.getString(0), context.getString(R.string.account_type))
+
+                        if (tasksInstalled) {
+                            if (ContentResolver.getIsSyncable(account, TaskProvider.ProviderName.OpenTasks.authority) <= 0) {
+                                ContentResolver.setIsSyncable(account, TaskProvider.ProviderName.OpenTasks.authority, 1)
+                                ContentResolver.setSyncAutomatically(account, TaskProvider.ProviderName.OpenTasks.authority, true)
+                                ContentResolver.addPeriodicSync(account, TaskProvider.ProviderName.OpenTasks.authority, Bundle(), Constants.DEFAULT_SYNC_INTERVAL)
+                            }
+                        } else
+                            ContentResolver.setIsSyncable(account, TaskProvider.ProviderName.OpenTasks.authority, 0)
+
+                    }
+                }
+            }
+        }
+
+    }
+
+}

app/src/main/java/at/bitfire/davdroid/SSLSocketFactoryCompat.java

@@ -1,172 +0,0 @@
-/*
- * Copyright © 2013 – 2015 Ricki Hirner (bitfire web engineering).
- * All rights reserved. This program and the accompanying materials
- * are made available under the terms of the GNU Public License v3.0
- * which accompanies this distribution, and is available at
- * http://www.gnu.org/licenses/gpl.html
- */
-
-package at.bitfire.davdroid;
-
-import android.os.Build;
-import android.support.annotation.NonNull;
-import android.text.TextUtils;
-
-import java.io.IOException;
-import java.net.InetAddress;
-import java.net.Socket;
-import java.net.UnknownHostException;
-import java.security.GeneralSecurityException;
-import java.util.Arrays;
-import java.util.HashSet;
-import java.util.LinkedList;
-import java.util.List;
-import java.util.Locale;
-
-import javax.net.ssl.SSLContext;
-import javax.net.ssl.SSLSocket;
-import javax.net.ssl.SSLSocketFactory;
-import javax.net.ssl.X509TrustManager;
-
-import de.duenndns.ssl.MemorizingTrustManager;
-import lombok.Cleanup;
-
-public class SSLSocketFactoryCompat extends SSLSocketFactory {
-
-    private SSLSocketFactory delegate;
-
-    // Android 5.0+ (API level21) provides reasonable default settings
-    // but it still allows SSLv3
-    // https://developer.android.com/reference/javax/net/ssl/SSLSocket.html
-    static String protocols[] = null, cipherSuites[] = null;
-    static {
-        try {
-            @Cleanup SSLSocket socket = (SSLSocket)SSLSocketFactory.getDefault().createSocket();
-            if (socket != null) {
-                /* set reasonable protocol versions */
-                // - enable all supported protocols (enables TLSv1.1 and TLSv1.2 on Android <5.0)
-                // - remove all SSL versions (especially SSLv3) because they're insecure now
-                List<String> protocols = new LinkedList<>();
-                for (String protocol : socket.getSupportedProtocols())
-                    if (!protocol.toUpperCase(Locale.US).contains("SSL"))
-                        protocols.add(protocol);
-                App.log.info("Setting allowed TLS protocols: " + TextUtils.join(", ", protocols));
-                SSLSocketFactoryCompat.protocols = protocols.toArray(new String[protocols.size()]);
-
-                /* set up reasonable cipher suites */
-                if (Build.VERSION.SDK_INT < Build.VERSION_CODES.LOLLIPOP) {
-                    // choose known secure cipher suites
-                    List<String> allowedCiphers = Arrays.asList(
-                            // TLS 1.2
-                            "TLS_RSA_WITH_AES_256_GCM_SHA384",
-                            "TLS_RSA_WITH_AES_128_GCM_SHA256",
-                            "TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA256",
-                            "TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256",
-                            "TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384",
-                            "TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256",
-                            "TLS_ECHDE_RSA_WITH_AES_128_GCM_SHA256",
-                            // maximum interoperability
-                            "TLS_RSA_WITH_3DES_EDE_CBC_SHA",
-                            "TLS_RSA_WITH_AES_128_CBC_SHA",
-                            // additionally
-                            "TLS_RSA_WITH_AES_256_CBC_SHA",
-                            "TLS_ECDHE_ECDSA_WITH_3DES_EDE_CBC_SHA",
-                            "TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA",
-                            "TLS_ECDHE_RSA_WITH_3DES_EDE_CBC_SHA",
-                            "TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA");
-                    List<String> availableCiphers = Arrays.asList(socket.getSupportedCipherSuites());
-                    App.log.fine("Available cipher suites: " + TextUtils.join(", ", availableCiphers));
-                    App.log.fine("Cipher suites enabled by default: " + TextUtils.join(", ", socket.getEnabledCipherSuites()));
-
-                    // take all allowed ciphers that are available and put them into preferredCiphers
-                    HashSet<String> preferredCiphers = new HashSet<>(allowedCiphers);
-                    preferredCiphers.retainAll(availableCiphers);
-
-                    /* For maximum security, preferredCiphers should *replace* enabled ciphers (thus disabling
-                     * ciphers which are enabled by default, but have become unsecure), but I guess for
-                     * the security level of DAVdroid and maximum compatibility, disabling of insecure
-                     * ciphers should be a server-side task */
-
-                    // add preferred ciphers to enabled ciphers
-                    HashSet<String> enabledCiphers = preferredCiphers;
-                    enabledCiphers.addAll(new HashSet<>(Arrays.asList(socket.getEnabledCipherSuites())));
-
-                    App.log.info("Enabling (only) those TLS ciphers: " + TextUtils.join(", ", enabledCiphers));
-                    SSLSocketFactoryCompat.cipherSuites = enabledCiphers.toArray(new String[enabledCiphers.size()]);
-                }
-            }
-        } catch (IOException e) {
-            App.log.severe("Couldn't determine default TLS settings");
-        }
-    }
-
-    public SSLSocketFactoryCompat(@NonNull MemorizingTrustManager mtm) {
-        try {
-            SSLContext sslContext = SSLContext.getInstance("TLS");
-            sslContext.init(null, new X509TrustManager[] { mtm }, null);
-            delegate = sslContext.getSocketFactory();
-        } catch (GeneralSecurityException e) {
-            throw new AssertionError(); // The system has no TLS. Just give up.
-        }
-    }
-
-    private void upgradeTLS(SSLSocket ssl) {
-        if (protocols != null)
-            ssl.setEnabledProtocols(protocols);
-
-        if (cipherSuites != null)
-            ssl.setEnabledCipherSuites(cipherSuites);
-    }
-
-
-    @Override
-    public String[] getDefaultCipherSuites() {
-        return cipherSuites;
-    }
-
-    @Override
-    public String[] getSupportedCipherSuites() {
-        return cipherSuites;
-    }
-
-    @Override
-    public Socket createSocket(Socket s, String host, int port, boolean autoClose) throws IOException {
-        Socket ssl = delegate.createSocket(s, host, port, autoClose);
-        if (ssl instanceof SSLSocket)
-            upgradeTLS((SSLSocket)ssl);
-        return ssl;
-    }
-
-    @Override
-    public Socket createSocket(String host, int port) throws IOException {
-        Socket ssl = delegate.createSocket(host, port);
-        if (ssl instanceof SSLSocket)
-            upgradeTLS((SSLSocket)ssl);
-        return ssl;
-    }
-
-    @Override
-    public Socket createSocket(String host, int port, InetAddress localHost, int localPort) throws IOException {
-        Socket ssl = delegate.createSocket(host, port, localHost, localPort);
-        if (ssl instanceof SSLSocket)
-            upgradeTLS((SSLSocket)ssl);
-        return ssl;
-    }
-
-    @Override
-    public Socket createSocket(InetAddress host, int port) throws IOException {
-        Socket ssl = delegate.createSocket(host, port);
-        if (ssl instanceof SSLSocket)
-            upgradeTLS((SSLSocket)ssl);
-        return ssl;
-    }
-
-    @Override
-    public Socket createSocket(InetAddress address, int port, InetAddress localAddress, int localPort) throws IOException {
-        Socket ssl = delegate.createSocket(address, port, localAddress, localPort);
-        if (ssl instanceof SSLSocket)
-            upgradeTLS((SSLSocket)ssl);
-        return ssl;
-    }
-
-}

app/src/main/java/at/bitfire/davdroid/log/LogcatHandler.java

@@ -1,59 +0,0 @@
-/*
- * Copyright © 2013 – 2016 Ricki Hirner (bitfire web engineering).
- * All rights reserved. This program and the accompanying materials
- * are made available under the terms of the GNU Public License v3.0
- * which accompanies this distribution, and is available at
- * http://www.gnu.org/licenses/gpl.html
- */
-
-package at.bitfire.davdroid.log;
-
-import android.util.Log;
-
-import org.apache.commons.lang3.math.NumberUtils;
-
-import java.util.logging.Handler;
-import java.util.logging.Level;
-import java.util.logging.LogRecord;
-
-public class LogcatHandler extends Handler {
-    private static final int MAX_LINE_LENGTH = 3000;
-    public static final LogcatHandler INSTANCE = new LogcatHandler();
-
-    private LogcatHandler() {
-        super();
-        setFormatter(PlainTextFormatter.LOGCAT);
-        setLevel(Level.ALL);
-    }
-
-    @Override
-    public void publish(LogRecord r) {
-        String text = getFormatter().format(r);
-        int level = r.getLevel().intValue();
-
-        int end = text.length();
-        for (int pos = 0; pos < end; pos += MAX_LINE_LENGTH) {
-            String line = text.substring(pos, NumberUtils.min(pos + MAX_LINE_LENGTH, end));
-
-            if (level >= Level.SEVERE.intValue())
-                Log.e(r.getLoggerName(), line);
-            else if (level >= Level.WARNING.intValue())
-                Log.w(r.getLoggerName(), line);
-            else if (level >= Level.CONFIG.intValue())
-                Log.i(r.getLoggerName(), line);
-            else if (level >= Level.FINER.intValue())
-                Log.d(r.getLoggerName(), line);
-            else
-                Log.v(r.getLoggerName(), line);
-        }
-    }
-
-    @Override
-    public void flush() {
-    }
-
-    @Override
-    public void close() {
-    }
-
-}

app/src/main/java/at/bitfire/davdroid/log/LogcatHandler.kt

@@ -0,0 +1,50 @@
+/*
+ * Copyright © Ricki Hirner (bitfire web engineering).
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the GNU Public License v3.0
+ * which accompanies this distribution, and is available at
+ * http://www.gnu.org/licenses/gpl.html
+ */
+
+package at.bitfire.davdroid.log
+
+import android.util.Log
+
+import org.apache.commons.lang3.math.NumberUtils
+
+import java.util.logging.Handler
+import java.util.logging.Level
+import java.util.logging.LogRecord
+
+object LogcatHandler: Handler() {
+
+    private val MAX_LINE_LENGTH = 3000
+
+    init {
+        formatter = PlainTextFormatter.LOGCAT
+        level = Level.ALL
+    }
+
+    override fun publish(r: LogRecord) {
+        val text = formatter.format(r)
+        val level = r.level.intValue()
+
+        val end = text.length
+        var pos = 0
+        while (pos < end) {
+            val line = text.substring(pos, NumberUtils.min(pos + MAX_LINE_LENGTH, end))
+            when {
+                level >= Level.SEVERE.intValue()  -> Log.e(r.loggerName, line)
+                level >= Level.WARNING.intValue() -> Log.w(r.loggerName, line)
+                level >= Level.CONFIG.intValue()  -> Log.i(r.loggerName, line)
+                level >= Level.FINER.intValue()   -> Log.d(r.loggerName, line)
+                else                              -> Log.v(r.loggerName, line)
+            }
+            pos += MAX_LINE_LENGTH
+        }
+    }
+
+    override fun flush() {}
+    override fun close() {}
+
+}

app/src/main/java/at/bitfire/davdroid/log/Logger.kt

@@ -0,0 +1,109 @@
+/*
+ * Copyright © Ricki Hirner (bitfire web engineering).
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the GNU Public License v3.0
+ * which accompanies this distribution, and is available at
+ * http://www.gnu.org/licenses/gpl.html
+ */
+
+package at.bitfire.davdroid.log
+
+import android.app.PendingIntent
+import android.content.Context
+import android.content.Intent
+import android.content.SharedPreferences
+import android.os.Process
+import android.preference.PreferenceManager
+import android.support.v4.app.NotificationCompat
+import android.util.Log
+import at.bitfire.davdroid.App
+import at.bitfire.davdroid.Constants
+import at.bitfire.davdroid.R
+import at.bitfire.davdroid.ui.AppSettingsActivity
+import at.bitfire.davdroid.ui.NotificationUtils
+import org.apache.commons.lang3.time.DateFormatUtils
+import java.io.File
+import java.io.IOException
+import java.util.logging.FileHandler
+import java.util.logging.Level
+
+object Logger {
+
+    val LOG_TO_EXTERNAL_STORAGE = "log_to_external_storage"
+
+    @JvmField
+    val log = java.util.logging.Logger.getLogger("davdroid")!!
+
+
+    lateinit private var preferences: SharedPreferences
+
+    fun initialize(context: Context) {
+        preferences = PreferenceManager.getDefaultSharedPreferences(context)
+        preferences.registerOnSharedPreferenceChangeListener { _, s ->
+            if (s == LOG_TO_EXTERNAL_STORAGE)
+                reinitialize(context.applicationContext)
+        }
+
+        reinitialize(context.applicationContext)
+    }
+
+    private fun reinitialize(context: Context) {
+        val logToFile = preferences.getBoolean(LOG_TO_EXTERNAL_STORAGE, false)
+        val logVerbose = logToFile || Log.isLoggable(log.name, Log.DEBUG)
+
+        log.info("Verbose logging: $logVerbose; to file: $logToFile")
+
+        // set logging level according to preferences
+        val rootLogger = java.util.logging.Logger.getLogger("")
+        rootLogger.level = if (logVerbose) Level.ALL else Level.INFO
+
+        // remove all handlers and add our own logcat handler
+        rootLogger.useParentHandlers = false
+        rootLogger.handlers.forEach { rootLogger.removeHandler(it) }
+        rootLogger.addHandler(LogcatHandler)
+
+        val nm = NotificationUtils.createChannels(context)
+        // log to external file according to preferences
+        if (logToFile) {
+            val builder = NotificationCompat.Builder(context, NotificationUtils.CHANNEL_DEBUG)
+            builder .setSmallIcon(R.drawable.ic_sd_storage_notification)
+                    .setLargeIcon(App.getLauncherBitmap(context))
+                    .setContentTitle(context.getString(R.string.logging_davdroid_file_logging))
+                    .setLocalOnly(true)
+
+            val dir = context.getExternalFilesDir(null)
+            if (dir != null)
+                try {
+                    val fileName = File(dir, "davdroid-${Process.myPid()}-${DateFormatUtils.format(System.currentTimeMillis(), "yyyyMMdd-HHmmss")}.txt").toString()
+                    log.info("Logging to $fileName")
+
+                    val fileHandler = FileHandler(fileName)
+                    fileHandler.formatter = PlainTextFormatter.DEFAULT
+                    rootLogger.addHandler(fileHandler)
+
+                    val prefIntent = Intent(context, AppSettingsActivity::class.java)
+                    prefIntent.putExtra(AppSettingsActivity.EXTRA_SCROLL_TO, LOG_TO_EXTERNAL_STORAGE)
+
+                    builder .setContentText(dir.path)
+                            .setCategory(NotificationCompat.CATEGORY_STATUS)
+                            .setPriority(NotificationCompat.PRIORITY_HIGH)
+                            .setContentIntent(PendingIntent.getActivity(context, 0, prefIntent, PendingIntent.FLAG_UPDATE_CURRENT))
+                            .setStyle(NotificationCompat.BigTextStyle()
+                                    .bigText(context.getString(R.string.logging_to_external_storage, dir.path)))
+                            .setOngoing(true)
+
+                } catch(e: IOException) {
+                    log.log(Level.SEVERE, "Couldn't create external log file", e)
+
+                    builder .setContentText(context.getString(R.string.logging_couldnt_create_file, e.localizedMessage))
+                            .setCategory(NotificationCompat.CATEGORY_ERROR)
+                }
+            else
+                builder.setContentText(context.getString(R.string.logging_no_external_storage))
+
+            nm.notify(Constants.NOTIFICATION_EXTERNAL_FILE_LOGGING, builder.build())
+        } else
+            nm.cancel(Constants.NOTIFICATION_EXTERNAL_FILE_LOGGING)
+    }
+
+}

app/src/main/java/at/bitfire/davdroid/log/PlainTextFormatter.java

@@ -1,63 +0,0 @@
-/*
- * Copyright © 2013 – 2016 Ricki Hirner (bitfire web engineering).
- * All rights reserved. This program and the accompanying materials
- * are made available under the terms of the GNU Public License v3.0
- * which accompanies this distribution, and is available at
- * http://www.gnu.org/licenses/gpl.html
- */
-
-package at.bitfire.davdroid.log;
-
-import android.util.Log;
-
-import org.apache.commons.lang3.StringUtils;
-import org.apache.commons.lang3.time.DateFormatUtils;
-
-import java.util.logging.Formatter;
-import java.util.logging.LogRecord;
-
-public class PlainTextFormatter extends Formatter {
-    public final static PlainTextFormatter
-            LOGCAT = new PlainTextFormatter(true),
-            DEFAULT = new PlainTextFormatter(false);
-
-    private final boolean logcat;
-
-    private PlainTextFormatter(boolean onLogcat) {
-        this.logcat = onLogcat;
-    }
-
-    @Override
-    public String format(LogRecord r) {
-        StringBuilder builder = new StringBuilder();
-
-        if (!logcat) {
-            builder.append(DateFormatUtils.format(r.getMillis(), "yyyy-MM-dd HH:mm:ss"));
-            builder.append(String.format(" %d ", r.getThreadID()));
-        }
-
-        builder.append(String.format("[%s] %s", shortClassName(r.getSourceClassName()), r.getMessage()));
-
-        if (r.getThrown() != null) {
-            builder.append("\nEXCEPTION ");
-            builder.append(Log.getStackTraceString(r.getThrown()));
-        }
-
-        if (r.getParameters() != null) {
-            int idx = 1;
-            for (Object param : r.getParameters())
-                builder.append("\nPARAMETER #").append(idx).append(" = ").append(param);
-        }
-
-        if (!logcat)
-            builder.append("\n");
-
-        return builder.toString();
-    }
-
-    private String shortClassName(String className) {
-        String s = StringUtils.replace(className, "at.bitfire.davdroid.", "");
-        return StringUtils.replace(s, "at.bitfire.", "");
-    }
-
-}

app/src/main/java/at/bitfire/davdroid/log/PlainTextFormatter.kt

@@ -0,0 +1,61 @@
+/*
+ * Copyright © Ricki Hirner (bitfire web engineering).
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the GNU Public License v3.0
+ * which accompanies this distribution, and is available at
+ * http://www.gnu.org/licenses/gpl.html
+ */
+
+package at.bitfire.davdroid.log
+
+import org.apache.commons.lang3.StringUtils
+import org.apache.commons.lang3.exception.ExceptionUtils
+import org.apache.commons.lang3.time.DateFormatUtils
+import java.util.logging.Formatter
+import java.util.logging.LogRecord
+
+class PlainTextFormatter private constructor(
+        private val logcat: Boolean
+): Formatter() {
+
+    companion object {
+        @JvmField val LOGCAT = PlainTextFormatter(true)
+        @JvmField val DEFAULT = PlainTextFormatter(false)
+
+        val MAX_MESSAGE_LENGTH = 20000
+    }
+
+    override fun format(r: LogRecord): String {
+        val builder = StringBuilder()
+
+        if (!logcat)
+            builder .append(DateFormatUtils.format(r.millis, "yyyy-MM-dd HH:mm:ss"))
+                    .append(" ").append(r.threadID).append(" ")
+
+        val className = shortClassName(r.sourceClassName)
+        if (className != r.loggerName)
+            builder.append("[").append(className).append("] ")
+
+        builder.append(StringUtils.abbreviate(r.message, MAX_MESSAGE_LENGTH))
+
+        r.thrown?.let {
+            builder .append("\nEXCEPTION ")
+                    .append(ExceptionUtils.getStackTrace(it))
+        }
+
+        r.parameters?.let {
+            for ((idx, param) in it.withIndex())
+                builder.append("\n\tPARAMETER #").append(idx).append(" = ").append(param)
+        }
+
+        if (!logcat)
+            builder.append("\n")
+
+        return builder.toString()
+    }
+
+    private fun shortClassName(className: String) = className
+            .replace(Regex("^at\\.bitfire\\.(dav|cert4an|dav4an|ical4an|vcard4an)droid\\."), "")
+            .replace(Regex("\\$.*$"), "")
+
+}

app/src/main/java/at/bitfire/davdroid/log/StringHandler.java

@@ -1,40 +0,0 @@
-/*
- * Copyright © 2013 – 2016 Ricki Hirner (bitfire web engineering).
- * All rights reserved. This program and the accompanying materials
- * are made available under the terms of the GNU Public License v3.0
- * which accompanies this distribution, and is available at
- * http://www.gnu.org/licenses/gpl.html
- */
-
-package at.bitfire.davdroid.log;
-
-import java.util.logging.Handler;
-import java.util.logging.LogRecord;
-
-public class StringHandler extends Handler {
-
-    StringBuilder builder = new StringBuilder();
-
-    public StringHandler() {
-        super();
-        setFormatter(PlainTextFormatter.DEFAULT);
-    }
-
-    @Override
-    public void publish(LogRecord record) {
-        builder.append(getFormatter().format(record));
-    }
-
-    @Override
-    public void flush() {
-    }
-
-    @Override
-    public void close() {
-    }
-
-    @Override
-    public String toString() {
-        return builder.toString();
-    }
-}

app/src/main/java/at/bitfire/davdroid/log/StringHandler.kt

@@ -0,0 +1,31 @@
+/*
+ * Copyright © Ricki Hirner (bitfire web engineering).
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the GNU Public License v3.0
+ * which accompanies this distribution, and is available at
+ * http://www.gnu.org/licenses/gpl.html
+ */
+
+package at.bitfire.davdroid.log
+
+import java.util.logging.Handler
+import java.util.logging.LogRecord
+
+class StringHandler: Handler() {
+
+    val builder = StringBuilder()
+
+    init {
+        formatter = PlainTextFormatter.DEFAULT
+    }
+
+    override fun publish(record: LogRecord) {
+        builder.append(formatter.format(record))
+    }
+
+    override fun flush() {}
+    override fun close() {}
+
+    override fun toString() = builder.toString()
+
+}

app/src/main/java/at/bitfire/davdroid/model/CollectionInfo.java

@@ -1,161 +0,0 @@
-/*
- * Copyright © 2013 – 2016 Ricki Hirner (bitfire web engineering).
- * All rights reserved. This program and the accompanying materials
- * are made available under the terms of the GNU Public License v3.0
- * which accompanies this distribution, and is available at
- * http://www.gnu.org/licenses/gpl.html
- */
-
-package at.bitfire.davdroid.model;
-
-import android.content.ContentValues;
-
-import java.io.Serializable;
-
-import at.bitfire.dav4android.DavResource;
-import at.bitfire.dav4android.Property;
-import at.bitfire.dav4android.property.AddressbookDescription;
-import at.bitfire.dav4android.property.CalendarColor;
-import at.bitfire.dav4android.property.CalendarDescription;
-import at.bitfire.dav4android.property.CalendarTimezone;
-import at.bitfire.dav4android.property.CurrentUserPrivilegeSet;
-import at.bitfire.dav4android.property.DisplayName;
-import at.bitfire.dav4android.property.ResourceType;
-import at.bitfire.dav4android.property.SupportedAddressData;
-import at.bitfire.dav4android.property.SupportedCalendarComponentSet;
-import at.bitfire.davdroid.model.ServiceDB.Collections;
-import lombok.ToString;
-
-@ToString
-public class CollectionInfo implements Serializable {
-    public long id;
-    public Long serviceID;
-
-    public enum Type {
-        ADDRESS_BOOK,
-        CALENDAR
-    };
-    public Type type;
-
-    public String url;
-
-    public boolean readOnly;
-    public String displayName, description;
-    public Integer color;
-
-    public String timeZone;
-    public Boolean supportsVEVENT;
-    public Boolean supportsVTODO;
-
-    public boolean selected;
-
-    // non-persistent properties
-    public boolean confirmed;
-
-
-    public static final Property.Name[] DAV_PROPERTIES = {
-            ResourceType.NAME,
-            CurrentUserPrivilegeSet.NAME,
-            DisplayName.NAME,
-            AddressbookDescription.NAME, SupportedAddressData.NAME,
-            CalendarDescription.NAME, CalendarColor.NAME, SupportedCalendarComponentSet.NAME
-    };
-
-    public static CollectionInfo fromDavResource(DavResource dav) {
-        CollectionInfo info = new CollectionInfo();
-        info.url = dav.location.toString();
-
-        ResourceType type = (ResourceType)dav.properties.get(ResourceType.NAME);
-        if (type != null) {
-            if (type.types.contains(ResourceType.ADDRESSBOOK))
-                info.type = Type.ADDRESS_BOOK;
-            else if (type.types.contains(ResourceType.CALENDAR))
-                info.type = Type.CALENDAR;
-        }
-
-        boolean readOnly = false;
-        CurrentUserPrivilegeSet privilegeSet = (CurrentUserPrivilegeSet)dav.properties.get(CurrentUserPrivilegeSet.NAME);
-        if (privilegeSet != null)
-            readOnly = !privilegeSet.mayWriteContent;
-
-        DisplayName displayName = (DisplayName)dav.properties.get(DisplayName.NAME);
-        if (displayName != null && !displayName.displayName.isEmpty())
-            info.displayName = displayName.displayName;
-
-        if (info.type == Type.ADDRESS_BOOK) {
-            AddressbookDescription addressbookDescription = (AddressbookDescription)dav.properties.get(AddressbookDescription.NAME);
-            if (addressbookDescription != null)
-                info.description = addressbookDescription.description;
-
-        } else if (info.type == Type.CALENDAR) {
-            CalendarDescription calendarDescription = (CalendarDescription)dav.properties.get(CalendarDescription.NAME);
-            if (calendarDescription != null)
-                info.description = calendarDescription.description;
-
-            CalendarColor calendarColor = (CalendarColor)dav.properties.get(CalendarColor.NAME);
-            if (calendarColor != null)
-                info.color = calendarColor.color;
-
-            CalendarTimezone timeZone = (CalendarTimezone)dav.properties.get(CalendarTimezone.NAME);
-            if (timeZone != null)
-                info.timeZone = timeZone.vTimeZone;
-
-            info.supportsVEVENT = info.supportsVTODO = true;
-            SupportedCalendarComponentSet supportedCalendarComponentSet = (SupportedCalendarComponentSet)dav.properties.get(SupportedCalendarComponentSet.NAME);
-            if (supportedCalendarComponentSet != null) {
-                info.supportsVEVENT = supportedCalendarComponentSet.supportsEvents;
-                info.supportsVTODO = supportedCalendarComponentSet.supportsTasks;
-            }
-        }
-
-        return info;
-    }
-
-
-    public static CollectionInfo fromDB(ContentValues values) {
-        CollectionInfo info = new CollectionInfo();
-        info.id = values.getAsLong(Collections.ID);
-        info.serviceID = values.getAsLong(Collections.SERVICE_ID);
-
-        info.url = values.getAsString(Collections.URL);
-        info.displayName = values.getAsString(Collections.DISPLAY_NAME);
-        info.description = values.getAsString(Collections.DESCRIPTION);
-
-        info.color = values.getAsInteger(Collections.COLOR);
-
-        info.timeZone = values.getAsString(Collections.TIME_ZONE);
-        info.supportsVEVENT = booleanField(values, Collections.SUPPORTS_VEVENT);
-        info.supportsVTODO = booleanField(values, Collections.SUPPORTS_VTODO);
-
-        info.selected = booleanField(values, Collections.SYNC);
-        return info;
-    }
-
-    public ContentValues toDB() {
-        ContentValues values = new ContentValues();
-        // Collections.SERVICE_ID is never changed
-
-        values.put(Collections.URL, url);
-        values.put(Collections.DISPLAY_NAME, displayName);
-        values.put(Collections.DESCRIPTION, description);
-        values.put(Collections.COLOR, color);
-
-        values.put(Collections.TIME_ZONE, timeZone);
-        if (supportsVEVENT != null)
-            values.put(Collections.SUPPORTS_VEVENT, supportsVEVENT ? 1 : 0);
-        if (supportsVTODO != null)
-            values.put(Collections.SUPPORTS_VTODO, supportsVTODO ? 1 : 0);
-
-        values.put(Collections.SYNC, selected ? 1 : 0);
-        return values;
-    }
-
-
-    private static Boolean booleanField(ContentValues values, String field) {
-        Integer i = values.getAsInteger(field);
-        if (i == null)
-            return null;
-        return i != 0;
-    }
-
-}

app/src/main/java/at/bitfire/davdroid/model/CollectionInfo.kt

@@ -0,0 +1,163 @@
+/*
+ * Copyright © Ricki Hirner (bitfire web engineering).
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the GNU Public License v3.0
+ * which accompanies this distribution, and is available at
+ * http://www.gnu.org/licenses/gpl.html
+ */
+
+package at.bitfire.davdroid.model
+
+import android.content.ContentValues
+import at.bitfire.dav4android.DavResource
+import at.bitfire.dav4android.property.*
+import at.bitfire.davdroid.model.ServiceDB.Collections
+import java.io.Serializable
+
+data class CollectionInfo @JvmOverloads constructor(
+        val url: String,
+
+        var id: Long? = null,
+        var serviceID: Long? = null,
+
+        var type: Type? = null,
+
+        var readOnly: Boolean = false,
+        var forceReadOnly: Boolean = false,
+        var displayName: String? = null,
+        var description: String? = null,
+        var color: Int? = null,
+
+        var timeZone: String? = null,
+        var supportsVEVENT: Boolean = false,
+        var supportsVTODO: Boolean = false,
+        var selected: Boolean = false,
+
+        // subscriptions
+        var source: String? = null,
+
+        // non-persistent properties
+        var confirmed: Boolean = false
+): Serializable {
+
+    enum class Type {
+        ADDRESS_BOOK,
+        CALENDAR,
+        WEBCAL          // iCalendar subscription
+    }
+
+    companion object {
+
+        @JvmField
+        val DAV_PROPERTIES = arrayOf(
+            ResourceType.NAME,
+            CurrentUserPrivilegeSet.NAME,
+            DisplayName.NAME,
+            AddressbookDescription.NAME, SupportedAddressData.NAME,
+            CalendarDescription.NAME, CalendarColor.NAME, SupportedCalendarComponentSet.NAME,
+            Source.NAME
+        )
+
+    }
+
+
+    constructor(dav: DavResource): this(dav.location.toString()) {
+        dav.properties[ResourceType::class.java]?.let { type ->
+            when {
+                type.types.contains(ResourceType.ADDRESSBOOK) -> this.type = Type.ADDRESS_BOOK
+                type.types.contains(ResourceType.CALENDAR)    -> this.type = Type.CALENDAR
+                type.types.contains(ResourceType.SUBSCRIBED)  -> this.type = Type.WEBCAL
+            }
+        }
+
+        dav.properties[CurrentUserPrivilegeSet::class.java]?.let { privilegeSet ->
+            readOnly = !privilegeSet.mayWriteContent
+        }
+
+        dav.properties[DisplayName::class.java]?.let {
+            if (!it.displayName.isNullOrEmpty())
+                displayName = it.displayName
+        }
+
+        when (type) {
+            Type.ADDRESS_BOOK -> {
+                dav.properties[AddressbookDescription::class.java]?.let { description = it.description }
+            }
+            Type.CALENDAR, Type.WEBCAL -> {
+                dav.properties[CalendarDescription::class.java]?.let { description = it.description }
+                dav.properties[CalendarColor::class.java]?.let { color = it.color }
+                dav.properties[CalendarTimezone::class.java]?.let { timeZone = it.vTimeZone }
+
+                if (type == Type.CALENDAR) {
+                    supportsVEVENT = true
+                    supportsVTODO = true
+                    dav.properties[SupportedCalendarComponentSet::class.java]?.let {
+                        supportsVEVENT = it.supportsEvents
+                        supportsVTODO = it.supportsTasks
+                    }
+                } else { // Type.WEBCAL
+                    dav.properties[Source::class.java]?.let { source = it.hrefs.firstOrNull() }
+                    supportsVEVENT = true
+                }
+            }
+        }
+    }
+
+
+    constructor(values: ContentValues): this(values.getAsString(Collections.URL)) {
+        id = values.getAsLong(Collections.ID)
+        serviceID = values.getAsLong(Collections.SERVICE_ID)
+        type = try {
+            Type.valueOf(values.getAsString(Collections.TYPE))
+        } catch (e: Exception) {
+            null
+        }
+
+        readOnly = values.getAsInteger(Collections.READ_ONLY) != 0
+        forceReadOnly = values.getAsInteger(Collections.FORCE_READ_ONLY) != 0
+        displayName = values.getAsString(Collections.DISPLAY_NAME)
+        description = values.getAsString(Collections.DESCRIPTION)
+
+        color = values.getAsInteger(Collections.COLOR)
+
+        timeZone = values.getAsString(Collections.TIME_ZONE)
+        supportsVEVENT = getAsBooleanOrNull(values, Collections.SUPPORTS_VEVENT) ?: false
+        supportsVTODO = getAsBooleanOrNull(values, Collections.SUPPORTS_VTODO) ?: false
+
+        source = values.getAsString(Collections.SOURCE)
+
+        selected = values.getAsInteger(Collections.SYNC) != 0
+    }
+
+    fun toDB(): ContentValues {
+        val values = ContentValues()
+        // Collections.SERVICE_ID is never changed
+        type?.let { values.put(Collections.TYPE, it.name) }
+
+        values.put(Collections.URL, url)
+        values.put(Collections.READ_ONLY, if (readOnly) 1 else 0)
+        values.put(Collections.FORCE_READ_ONLY, if (forceReadOnly) 1 else 0)
+        values.put(Collections.DISPLAY_NAME, displayName)
+        values.put(Collections.DESCRIPTION, description)
+        values.put(Collections.COLOR, color)
+
+        values.put(Collections.TIME_ZONE, timeZone)
+        values.put(Collections.SUPPORTS_VEVENT, if (supportsVEVENT) 1 else 0)
+        values.put(Collections.SUPPORTS_VTODO, if (supportsVTODO) 1 else 0)
+
+        values.put(Collections.SOURCE, source)
+
+        values.put(Collections.SYNC, if (selected) 1 else 0)
+        return values
+    }
+
+
+    private fun getAsBooleanOrNull(values: ContentValues, field: String): Boolean? {
+        val i = values.getAsInteger(field)
+        return if (i == null)
+            null
+        else
+            (i != 0)
+    }
+
+}

app/src/main/java/at/bitfire/davdroid/model/Credentials.kt

@@ -0,0 +1,41 @@
+/*
+ * Copyright © Ricki Hirner (bitfire web engineering).
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the GNU Public License v3.0
+ * which accompanies this distribution, and is available at
+ * http://www.gnu.org/licenses/gpl.html
+ */
+
+package at.bitfire.davdroid.model
+
+import java.io.Serializable
+
+class Credentials @JvmOverloads constructor(
+        @JvmField val userName: String? = null,
+        @JvmField val password: String? = null,
+        @JvmField val certificateAlias: String? = null
+): Serializable {
+
+    enum class Type {
+        UsernamePassword,
+        ClientCertificate
+    }
+
+    val type: Type
+
+    init {
+        type = when {
+            !certificateAlias.isNullOrEmpty() ->
+                Type.ClientCertificate
+            !userName.isNullOrEmpty() && !password.isNullOrEmpty() ->
+                Type.UsernamePassword
+            else ->
+                throw IllegalArgumentException("Either username/password or certificate alias must be set")
+        }
+    }
+
+    override fun toString(): String {
+        return "Credentials(type=$type, userName=$userName, certificateAlias=$certificateAlias)"
+    }
+
+}

app/src/main/java/at/bitfire/davdroid/model/HomeSet.java

@@ -1,29 +0,0 @@
-/*
- * Copyright © 2013 – 2016 Ricki Hirner (bitfire web engineering).
- * All rights reserved. This program and the accompanying materials
- * are made available under the terms of the GNU Public License v3.0
- * which accompanies this distribution, and is available at
- * http://www.gnu.org/licenses/gpl.html
- */
-
-package at.bitfire.davdroid.model;
-
-import android.content.ContentValues;
-
-import lombok.ToString;
-
-@ToString
-public class HomeSet {
-
-    public long id, serviceID;
-    public String URL;
-
-    public static HomeSet fromDB(ContentValues values) {
-        HomeSet homeSet = new HomeSet();
-        homeSet.id = values.getAsLong(ServiceDB.HomeSets.ID);
-        homeSet.serviceID = values.getAsLong(ServiceDB.HomeSets.SERVICE_ID);
-        homeSet.URL = values.getAsString(ServiceDB.HomeSets.URL);
-        return homeSet;
-    }
-
-}

app/src/main/java/at/bitfire/davdroid/model/Service.java

@@ -1,29 +0,0 @@
-/*
- * Copyright © 2013 – 2016 Ricki Hirner (bitfire web engineering).
- * All rights reserved. This program and the accompanying materials
- * are made available under the terms of the GNU Public License v3.0
- * which accompanies this distribution, and is available at
- * http://www.gnu.org/licenses/gpl.html
- */
-
-package at.bitfire.davdroid.model;
-
-import android.content.ContentValues;
-
-public class Service {
-
-    public long id;
-    public String accountName, service, principal;
-    public long lastRefresh;
-
-
-    public static Service fromDB(ContentValues values) {
-        Service service = new Service();
-        service.id = values.getAsLong(ServiceDB.Services.ID);
-        service.accountName = values.getAsString(ServiceDB.Services.ACCOUNT_NAME);
-        service.service = values.getAsString(ServiceDB.Services.SERVICE);
-        service.principal = values.getAsString(ServiceDB.Services.PRINCIPAL);
-        return service;
-    }
-
-}

app/src/main/java/at/bitfire/davdroid/model/ServiceDB.java

@@ -1,170 +0,0 @@
-/*
- * Copyright © 2013 – 2016 Ricki Hirner (bitfire web engineering).
- * All rights reserved. This program and the accompanying materials
- * are made available under the terms of the GNU Public License v3.0
- * which accompanies this distribution, and is available at
- * http://www.gnu.org/licenses/gpl.html
- */
-
-package at.bitfire.davdroid.model;
-
-import android.content.Context;
-import android.database.Cursor;
-import android.database.sqlite.SQLiteDatabase;
-import android.database.sqlite.SQLiteException;
-import android.database.sqlite.SQLiteOpenHelper;
-import android.os.Build;
-
-import at.bitfire.davdroid.App;
-import lombok.Cleanup;
-
-public class ServiceDB {
-
-    public static class Services {
-        public static final String
-                _TABLE = "services",
-                ID = "_id",
-                ACCOUNT_NAME = "accountName",
-                SERVICE = "service",
-                PRINCIPAL = "principal";
-
-        // allowed values for SERVICE column
-        public static final String
-                SERVICE_CALDAV = "caldav",
-                SERVICE_CARDDAV = "carddav";
-    }
-
-    public static class HomeSets {
-        public static final String
-                _TABLE = "homesets",
-                ID = "_id",
-                SERVICE_ID = "serviceID",
-                URL = "url";
-    }
-
-    public static class Collections {
-        public static final String
-                _TABLE = "collections",
-                ID = "_id",
-                SERVICE_ID = "serviceID",
-                URL = "url",
-                DISPLAY_NAME = "displayName",
-                DESCRIPTION = "description",
-                COLOR = "color",
-                TIME_ZONE = "timezone",
-                SUPPORTS_VEVENT = "supportsVEVENT",
-                SUPPORTS_VTODO = "supportsVTODO",
-                SYNC = "sync";
-
-        public static String[] _COLUMNS = new String[] {
-                ID, SERVICE_ID, URL, DISPLAY_NAME, DESCRIPTION, COLOR,
-                TIME_ZONE, SUPPORTS_VEVENT, SUPPORTS_VTODO,
-                SYNC
-        };
-    }
-
-
-    public static class OpenHelper extends SQLiteOpenHelper {
-        private static final String DATABASE_NAME = "services.db";
-        private static final int DATABASE_VERSION = 1;
-
-        public OpenHelper(Context context) {
-            super(context, DATABASE_NAME, null, DATABASE_VERSION);
-        }
-
-        @Override
-        public void onOpen(SQLiteDatabase db) {
-            db.enableWriteAheadLogging();
-            if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.JELLY_BEAN)
-                db.setForeignKeyConstraintsEnabled(true);
-            else
-                db.execSQL("PRAGMA foreign_keys=ON;");
-        }
-
-        @Override
-        public void onCreate(SQLiteDatabase db) {
-            App.log.info("Creating services database");
-
-            db.execSQL("CREATE TABLE " + Services._TABLE + "(" +
-                    Services.ID + " INTEGER PRIMARY KEY AUTOINCREMENT," +
-                    Services.ACCOUNT_NAME + " TEXT NOT NULL," +
-                    Services.SERVICE + " TEXT NOT NULL," +
-                    Services.PRINCIPAL + " TEXT NULL" +
-            ")");
-            db.execSQL("CREATE UNIQUE INDEX services_account ON " + Services._TABLE + " (" + Services.ACCOUNT_NAME + "," + Services.SERVICE + ")");
-
-            db.execSQL("CREATE TABLE " + HomeSets._TABLE + "(" +
-                    HomeSets.ID + " INTEGER PRIMARY KEY AUTOINCREMENT," +
-                    HomeSets.SERVICE_ID + " INTEGER NOT NULL REFERENCES " + Services._TABLE +" ON DELETE CASCADE," +
-                    HomeSets.URL + " TEXT NOT NULL" +
-             ")");
-            db.execSQL("CREATE UNIQUE INDEX homesets_service_url ON " + HomeSets._TABLE + "(" + HomeSets.SERVICE_ID + "," + HomeSets.URL + ")");
-
-            db.execSQL("CREATE TABLE " + Collections._TABLE + "(" +
-                    Collections.ID + " INTEGER PRIMARY KEY AUTOINCREMENT," +
-                    Collections.SERVICE_ID + " INTEGER NOT NULL REFERENCES " + Services._TABLE +" ON DELETE CASCADE," +
-                    Collections.URL + " TEXT NOT NULL," +
-                    Collections.DISPLAY_NAME + " TEXT NULL," +
-                    Collections.DESCRIPTION + " TEXT NULL," +
-                    Collections.COLOR + " INTEGER NULL," +
-                    Collections.TIME_ZONE + " TEXt NULL," +
-                    Collections.SUPPORTS_VEVENT + " INTEGER NULL," +
-                    Collections.SUPPORTS_VTODO + " INTEGER NULL," +
-                    Collections.SYNC + " INTEGER DEFAULT 0 NOT NULL" +
-            ")");
-            db.execSQL("CREATE UNIQUE INDEX collections_service_url ON " + Collections._TABLE + "(" + Collections.SERVICE_ID + "," + Collections.URL + ")");
-        }
-
-        @Override
-        public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
-        }
-
-
-        public void dump(StringBuilder sb) {
-            SQLiteDatabase db = getReadableDatabase();
-            db.beginTransactionNonExclusive();
-
-            // iterate through all tables
-            @Cleanup Cursor cursorTables = db.query("sqlite_master", new String[] { "name" }, "type='table'", null, null, null, null);
-            while (cursorTables.moveToNext()) {
-                String table = cursorTables.getString(0);
-                sb.append("\t").append(table).append("\n");
-                @Cleanup Cursor cursor = db.query(table, null, null, null, null, null, null);
-
-                // print columns
-                int cols = cursor.getColumnCount();
-                sb.append("\t\t| ");
-                for (int i = 0; i < cols; i++) {
-                    sb.append(" ");
-                    sb.append(cursor.getColumnName(i));
-                    sb.append(" |");
-                }
-                sb.append("\n");
-
-                // print rows
-                while (cursor.moveToNext()) {
-                    sb.append("\t\t| ");
-                    for (int i = 0; i < cols; i++) {
-                        sb.append(" ");
-                        try {
-                            String value = cursor.getString(i);
-                            if (value != null)
-                                sb.append(value
-                                        .replace("\r", "<CR>")
-                                        .replace("\n", "<LF>"));
-                            else
-                                sb.append("<null>");
-
-                        } catch (SQLiteException e) {
-                            sb.append("<unprintable>");
-                        }
-                        sb.append(" |");
-                    }
-                    sb.append("\n");
-                }
-            }
-            db.endTransaction();
-        }
-    }
-
-}

app/src/main/java/at/bitfire/davdroid/model/ServiceDB.kt

@@ -0,0 +1,231 @@
+/*
+ * Copyright © Ricki Hirner (bitfire web engineering).
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the GNU Public License v3.0
+ * which accompanies this distribution, and is available at
+ * http://www.gnu.org/licenses/gpl.html
+ */
+
+package at.bitfire.davdroid.model
+
+import android.content.ContentValues
+import android.content.Context
+import android.database.sqlite.SQLiteDatabase
+import android.database.sqlite.SQLiteException
+import android.database.sqlite.SQLiteOpenHelper
+import android.preference.PreferenceManager
+import at.bitfire.davdroid.App
+import at.bitfire.davdroid.log.Logger
+import at.bitfire.davdroid.ui.StartupDialogFragment
+import java.io.Closeable
+import java.util.logging.Level
+
+class ServiceDB {
+
+    /*object Settings {
+        @JvmField val _TABLE = "settings"
+        @JvmField val NAME = "setting"
+        @JvmField val VALUE = "value"
+    }*/
+
+    object Services {
+        @JvmField val _TABLE = "services"
+        @JvmField val ID = "_id"
+        @JvmField val ACCOUNT_NAME = "accountName"
+        @JvmField val SERVICE = "service"
+        @JvmField val PRINCIPAL = "principal"
+
+        // allowed values for SERVICE column
+        @JvmField val SERVICE_CALDAV = "caldav"
+        @JvmField val SERVICE_CARDDAV = "carddav"
+    }
+
+    object HomeSets {
+        @JvmField val _TABLE = "homesets"
+        @JvmField val ID = "_id"
+        @JvmField val SERVICE_ID = "serviceID"
+        @JvmField val URL = "url"
+    }
+
+    object Collections {
+        @JvmField val _TABLE = "collections"
+        @JvmField val ID = "_id"
+        @JvmField val TYPE = "type"
+        @JvmField val SERVICE_ID = "serviceID"
+        @JvmField val URL = "url"
+        @JvmField val READ_ONLY = "readOnly"
+        @JvmField val FORCE_READ_ONLY = "forceReadOnly"
+        @JvmField val DISPLAY_NAME = "displayName"
+        @JvmField val DESCRIPTION = "description"
+        @JvmField val COLOR = "color"
+        @JvmField val TIME_ZONE = "timezone"
+        @JvmField val SUPPORTS_VEVENT = "supportsVEVENT"
+        @JvmField val SUPPORTS_VTODO = "supportsVTODO"
+        @JvmField val SOURCE = "source"
+        @JvmField val SYNC = "sync"
+    }
+
+    companion object {
+
+        @JvmStatic
+        fun onRenameAccount(db: SQLiteDatabase, oldName: String, newName: String) {
+            val values = ContentValues(1)
+            values.put(Services.ACCOUNT_NAME, newName)
+            db.updateWithOnConflict(Services._TABLE, values, Services.ACCOUNT_NAME + "=?", arrayOf(oldName), SQLiteDatabase.CONFLICT_REPLACE)
+        }
+
+    }
+
+
+    class OpenHelper(
+            val context: Context
+    ): SQLiteOpenHelper(context, DATABASE_NAME, null, DATABASE_VERSION), Closeable {
+
+        companion object {
+            val DATABASE_NAME = "services.db"
+            val DATABASE_VERSION = 4
+        }
+
+        override fun onConfigure(db: SQLiteDatabase) {
+            setWriteAheadLoggingEnabled(true)
+            db.setForeignKeyConstraintsEnabled(true)
+        }
+
+        override fun onCreate(db: SQLiteDatabase) {
+            Logger.log.info("Creating database " + db.path)
+
+            db.execSQL("CREATE TABLE ${Services._TABLE}(" +
+                    "${Services.ID} INTEGER PRIMARY KEY AUTOINCREMENT," +
+                    "${Services.ACCOUNT_NAME} TEXT NOT NULL," +
+                    "${Services.SERVICE} TEXT NOT NULL," +
+                    "${Services.PRINCIPAL} TEXT NULL)")
+            db.execSQL("CREATE UNIQUE INDEX services_account ON ${Services._TABLE} (${Services.ACCOUNT_NAME},${Services.SERVICE})")
+
+            db.execSQL("CREATE TABLE ${HomeSets._TABLE}(" +
+                    "${HomeSets.ID} INTEGER PRIMARY KEY AUTOINCREMENT," +
+                    "${HomeSets.SERVICE_ID} INTEGER NOT NULL REFERENCES ${Services._TABLE} ON DELETE CASCADE," +
+                    "${HomeSets.URL} TEXT NOT NULL)")
+            db.execSQL("CREATE UNIQUE INDEX homesets_service_url ON ${HomeSets._TABLE}(${HomeSets.SERVICE_ID},${HomeSets.URL})")
+
+            db.execSQL("CREATE TABLE ${Collections._TABLE}(" +
+                    "${Collections.ID} INTEGER PRIMARY KEY AUTOINCREMENT," +
+                    "${Collections.SERVICE_ID} INTEGER NOT NULL REFERENCES ${Services._TABLE} ON DELETE CASCADE," +
+                    "${Collections.TYPE} TEXT NOT NULL," +
+                    "${Collections.URL} TEXT NOT NULL," +
+                    "${Collections.READ_ONLY} INTEGER DEFAULT 0 NOT NULL," +
+                    "${Collections.FORCE_READ_ONLY} INTEGER DEFAULT 0 NOT NULL," +
+                    "${Collections.DISPLAY_NAME} TEXT NULL," +
+                    "${Collections.DESCRIPTION} TEXT NULL," +
+                    "${Collections.COLOR} INTEGER NULL," +
+                    "${Collections.TIME_ZONE} TEXT NULL," +
+                    "${Collections.SUPPORTS_VEVENT} INTEGER NULL," +
+                    "${Collections.SUPPORTS_VTODO} INTEGER NULL," +
+                    "${Collections.SOURCE} TEXT NULL," +
+                    "${Collections.SYNC} INTEGER DEFAULT 0 NOT NULL)")
+            db.execSQL("CREATE UNIQUE INDEX collections_service_url ON ${Collections._TABLE}(${Collections.SERVICE_ID},${Collections.URL})")
+        }
+
+        override fun onUpgrade(db: SQLiteDatabase, oldVersion: Int, newVersion: Int) {
+            for (upgradeFrom in oldVersion until newVersion) {
+                val upgradeTo = upgradeFrom + 1
+                Logger.log.info("Upgrading database from version $upgradeFrom to $upgradeTo")
+                try {
+                    val upgradeProc = this::class.java.getDeclaredMethod("upgrade_${upgradeFrom}_$upgradeTo", SQLiteDatabase::class.java)
+                    upgradeProc.invoke(this, db)
+                } catch(e: Exception) {
+                    Logger.log.log(Level.SEVERE, "Couldn't upgrade database", e)
+                }
+            }
+        }
+
+        @Suppress("unused")
+        private fun upgrade_3_4(db: SQLiteDatabase) {
+            db.execSQL("ALTER TABLE ${Collections._TABLE} ADD COLUMN ${Collections.FORCE_READ_ONLY} INTEGER DEFAULT 0 NOT NULL")
+        }
+
+        @Suppress("unused")
+        private fun upgrade_2_3(db: SQLiteDatabase) {
+            val edit = PreferenceManager.getDefaultSharedPreferences(context).edit()
+            try {
+                db.query("settings", arrayOf("setting", "value"), null, null, null, null, null).use { cursor ->
+                    while (cursor.moveToNext()) {
+                        when (cursor.getString(0)) {
+                            "distrustSystemCerts" -> edit.putBoolean(App.DISTRUST_SYSTEM_CERTIFICATES, cursor.getInt(1) != 0)
+                            "overrideProxy" -> edit.putBoolean(App.OVERRIDE_PROXY, cursor.getInt(1) != 0)
+                            "overrideProxyHost" -> edit.putString(App.OVERRIDE_PROXY_HOST, cursor.getString(1))
+                            "overrideProxyPort" -> edit.putInt(App.OVERRIDE_PROXY_PORT, cursor.getInt(1))
+
+                            StartupDialogFragment.HINT_GOOGLE_PLAY_ACCOUNTS_REMOVED ->
+                                edit.putBoolean(StartupDialogFragment.HINT_GOOGLE_PLAY_ACCOUNTS_REMOVED, cursor.getInt(1) != 0)
+                            StartupDialogFragment.HINT_OPENTASKS_NOT_INSTALLED ->
+                                edit.putBoolean(StartupDialogFragment.HINT_OPENTASKS_NOT_INSTALLED, cursor.getInt(1) != 0)
+                        }
+                    }
+                }
+                db.execSQL("DROP TABLE settings")
+            } finally {
+                edit.apply()
+            }
+        }
+
+        @Suppress("unused")
+        private fun upgrade_1_2(db: SQLiteDatabase) {
+            db.execSQL("ALTER TABLE ${Collections._TABLE} ADD COLUMN ${Collections.TYPE} TEXT NOT NULL DEFAULT ''")
+            db.execSQL("ALTER TABLE ${Collections._TABLE} ADD COLUMN ${Collections.SOURCE} TEXT NULL")
+            db.execSQL("UPDATE ${Collections._TABLE} SET ${Collections.TYPE}=(" +
+                    "SELECT CASE ${Services.SERVICE} WHEN ? THEN ? ELSE ? END " +
+                    "FROM ${Services._TABLE} WHERE ${Services.ID}=${Collections._TABLE}.${Collections.SERVICE_ID}" +
+                    ")",
+                    arrayOf(Services.SERVICE_CALDAV, CollectionInfo.Type.CALENDAR, CollectionInfo.Type.ADDRESS_BOOK))
+        }
+
+
+        fun dump(sb: StringBuilder) {
+            val db = readableDatabase
+            db.beginTransactionNonExclusive()
+
+            // iterate through all tables
+            db.query("sqlite_master", arrayOf("name"), "type='table'", null, null, null, null).use { cursorTables ->
+                while (cursorTables.moveToNext()) {
+                    val table = cursorTables.getString(0)
+                    sb.append(table).append("\n")
+                    db.query(table, null, null, null, null, null, null).use { cursor ->
+                        // print columns
+                        val cols = cursor.columnCount
+                        sb.append("\t| ")
+                        for (i in 0 until cols)
+                            sb  .append(" ")
+                                .append(cursor.getColumnName(i))
+                                .append(" |")
+                        sb.append("\n")
+
+                        // print rows
+                        while (cursor.moveToNext()) {
+                            sb.append("\t| ")
+                            for (i in 0 until cols) {
+                                sb.append(" ")
+                                try {
+                                    val value = cursor.getString(i)
+                                    if (value != null)
+                                        sb.append(value
+                                                .replace("\r", "<CR>")
+                                                .replace("\n", "<LF>"))
+                                    else
+                                        sb.append("<null>")
+
+                                } catch (e: SQLiteException) {
+                                    sb.append("<unprintable>")
+                                }
+                                sb.append(" |")
+                            }
+                            sb.append("\n")
+                        }
+                        sb.append("----------\n")
+                    }
+                }
+                db.endTransaction()
+            }
+        }
+    }
+
+}

app/src/main/java/at/bitfire/davdroid/model/UnknownProperties.kt

@@ -0,0 +1,28 @@
+/*
+ * Copyright © Ricki Hirner (bitfire web engineering).
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the GNU Public License v3.0
+ * which accompanies this distribution, and is available at
+ * http://www.gnu.org/licenses/gpl.html
+ */
+
+package at.bitfire.davdroid.model
+
+import android.provider.ContactsContract.RawContacts
+
+object UnknownProperties {
+
+    @JvmField
+    val CONTENT_ITEM_TYPE = "x.davdroid/unknown-properties"
+
+
+    @JvmField
+    val MIMETYPE = RawContacts.Data.MIMETYPE
+
+    @JvmField
+    val RAW_CONTACT_ID = RawContacts.Data.RAW_CONTACT_ID
+
+    @JvmField
+    val UNKNOWN_PROPERTIES = RawContacts.Data.DATA1
+
+}

app/src/main/java/at/bitfire/davdroid/resource/LocalAddressBook.java

@@ -1,215 +0,0 @@
-/*
- * Copyright © 2013 – 2015 Ricki Hirner (bitfire web engineering).
- * All rights reserved. This program and the accompanying materials
- * are made available under the terms of the GNU Public License v3.0
- * which accompanies this distribution, and is available at
- * http://www.gnu.org/licenses/gpl.html
- */
-package at.bitfire.davdroid.resource;
-
-import android.accounts.Account;
-import android.content.ContentProviderClient;
-import android.content.ContentUris;
-import android.content.ContentValues;
-import android.database.Cursor;
-import android.os.Bundle;
-import android.os.Parcel;
-import android.os.RemoteException;
-import android.provider.ContactsContract;
-import android.provider.ContactsContract.CommonDataKinds.GroupMembership;
-import android.provider.ContactsContract.Data;
-import android.provider.ContactsContract.Groups;
-import android.provider.ContactsContract.RawContacts;
-
-import java.util.LinkedList;
-import java.util.List;
-
-import at.bitfire.davdroid.App;
-import at.bitfire.vcard4android.AndroidAddressBook;
-import at.bitfire.vcard4android.AndroidContact;
-import at.bitfire.vcard4android.AndroidGroupFactory;
-import at.bitfire.vcard4android.ContactsStorageException;
-import lombok.Cleanup;
-
-
-public class LocalAddressBook extends AndroidAddressBook implements LocalCollection {
-
-    protected static final String
-            SYNC_STATE_CTAG = "ctag",
-            SYNC_STATE_URL = "url";
-
-    private final Bundle syncState = new Bundle();
-
-
-    public LocalAddressBook(Account account, ContentProviderClient provider) {
-        super(account, provider, AndroidGroupFactory.INSTANCE, LocalContact.Factory.INSTANCE);
-    }
-
-
-    /**
-     * Returns an array of local contacts, excluding those which have been modified locally (and not uploaded yet).
-     */
-    @Override
-    public LocalContact[] getAll() throws ContactsStorageException {
-        return (LocalContact[])queryContacts(null, null);
-    }
-
-    /**
-     * Returns an array of local contacts which have been deleted locally. (DELETED != 0).
-     */
-    @Override
-    public LocalContact[] getDeleted() throws ContactsStorageException {
-        return (LocalContact[])queryContacts(RawContacts.DELETED + "!=0", null);
-    }
-
-    /**
-     * Returns an array of local contacts which have been changed locally (DIRTY != 0).
-     */
-    @Override
-    public LocalContact[] getDirty() throws ContactsStorageException {
-        return (LocalContact[])queryContacts(RawContacts.DIRTY + "!=0", null);
-    }
-
-    /**
-     * Returns an array of local contacts which don't have a file name yet.
-     */
-    @Override
-    public LocalContact[] getWithoutFileName() throws ContactsStorageException {
-        return (LocalContact[])queryContacts(AndroidContact.COLUMN_FILENAME + " IS NULL", null);
-    }
-
-    public void deleteAll()  throws ContactsStorageException {
-        try {
-            provider.delete(syncAdapterURI(RawContacts.CONTENT_URI), null, null);
-        } catch (RemoteException e) {
-            throw new ContactsStorageException("Couldn't delete all local contacts", e);
-        }
-    }
-
-
-    // GROUPS
-
-    /**
-     * Finds the first group with the given title.
-     * @param displayName   title of the group to look for
-     * @return              group with given title, or null if none
-     */
-    @SuppressWarnings("Recycle")
-    public LocalGroup findGroupByTitle(String displayName) throws ContactsStorageException {
-        try {
-            @Cleanup Cursor cursor = provider.query(syncAdapterURI(Groups.CONTENT_URI),
-                    new String[] { Groups._ID },
-                    ContactsContract.Groups.TITLE + "=?", new String[] { displayName }, null);
-            if (cursor != null && cursor.moveToNext())
-                return new LocalGroup(this, cursor.getLong(0));
-        } catch (RemoteException e) {
-            throw new ContactsStorageException("Couldn't find local contact group", e);
-        }
-        return null;
-    }
-
-    @SuppressWarnings("Recycle")
-    public LocalGroup[] getDeletedGroups() throws ContactsStorageException {
-        List<LocalGroup> groups = new LinkedList<>();
-        try {
-            @Cleanup Cursor cursor = provider.query(syncAdapterURI(Groups.CONTENT_URI),
-                    new String[] { Groups._ID },
-                    Groups.DELETED + "!=0", null, null);
-            while (cursor != null && cursor.moveToNext())
-                groups.add(new LocalGroup(this, cursor.getLong(0)));
-        } catch (RemoteException e) {
-            throw new ContactsStorageException("Couldn't query deleted groups", e);
-        }
-        return groups.toArray(new LocalGroup[groups.size()]);
-    }
-
-    @SuppressWarnings("Recycle")
-    public LocalGroup[] getDirtyGroups() throws ContactsStorageException {
-        List<LocalGroup> groups = new LinkedList<>();
-        try {
-            @Cleanup Cursor cursor = provider.query(syncAdapterURI(Groups.CONTENT_URI),
-                    new String[] { Groups._ID },
-                    Groups.DIRTY + "!=0", null, null);
-            while (cursor != null && cursor.moveToNext())
-                groups.add(new LocalGroup(this, cursor.getLong(0)));
-        } catch (RemoteException e) {
-            throw new ContactsStorageException("Couldn't query dirty groups", e);
-        }
-        return groups.toArray(new LocalGroup[groups.size()]);
-    }
-
-    @SuppressWarnings("Recycle")
-    public void markMembersDirty(long groupId) throws ContactsStorageException {
-        ContentValues dirty = new ContentValues(1);
-        dirty.put(RawContacts.DIRTY, 1);
-        try {
-            // query all GroupMemberships of this groupId, mark every corresponding raw contact as DIRTY
-            @Cleanup Cursor cursor = provider.query(syncAdapterURI(Data.CONTENT_URI),
-                    new String[] { GroupMembership.RAW_CONTACT_ID },
-                    Data.MIMETYPE + "=? AND " + GroupMembership.GROUP_ROW_ID + "=?",
-                    new String[] { GroupMembership.CONTENT_ITEM_TYPE, String.valueOf(groupId) }, null);
-            while (cursor != null && cursor.moveToNext()) {
-                long id = cursor.getLong(0);
-                App.log.fine("Marking raw contact #" + id + " as dirty");
-                provider.update(syncAdapterURI(ContentUris.withAppendedId(RawContacts.CONTENT_URI, id)), dirty, null, null);
-            }
-        } catch (RemoteException e) {
-            throw new ContactsStorageException("Couldn't query dirty groups", e);
-        }
-    }
-
-
-    // SYNC STATE
-
-    @SuppressWarnings("Recycle")
-    protected void readSyncState() throws ContactsStorageException {
-        @Cleanup("recycle") Parcel parcel = Parcel.obtain();
-        byte[] raw = getSyncState();
-        syncState.clear();
-        if (raw != null) {
-            parcel.unmarshall(raw, 0, raw.length);
-            parcel.setDataPosition(0);
-            syncState.putAll(parcel.readBundle());
-        }
-    }
-
-    @SuppressWarnings("Recycle")
-    protected void writeSyncState() throws ContactsStorageException {
-        @Cleanup("recycle") Parcel parcel = Parcel.obtain();
-        parcel.writeBundle(syncState);
-        setSyncState(parcel.marshall());
-    }
-
-    public String getURL() throws ContactsStorageException {
-        synchronized (syncState) {
-            readSyncState();
-            return syncState.getString(SYNC_STATE_URL);
-        }
-    }
-
-    public void setURL(String url) throws ContactsStorageException {
-        synchronized (syncState) {
-            readSyncState();
-            syncState.putString(SYNC_STATE_URL, url);
-            writeSyncState();
-        }
-    }
-
-    @Override
-    public String getCTag() throws ContactsStorageException {
-        synchronized (syncState) {
-            readSyncState();
-            return syncState.getString(SYNC_STATE_CTAG);
-        }
-    }
-
-    @Override
-    public void setCTag(String cTag) throws ContactsStorageException {
-        synchronized (syncState) {
-            readSyncState();
-            syncState.putString(SYNC_STATE_CTAG, cTag);
-            writeSyncState();
-        }
-    }
-
-}

app/src/main/java/at/bitfire/davdroid/resource/LocalAddressBook.kt

@@ -0,0 +1,366 @@
+/*
+ * Copyright © Ricki Hirner (bitfire web engineering).
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the GNU Public License v3.0
+ * which accompanies this distribution, and is available at
+ * http://www.gnu.org/licenses/gpl.html
+ */
+package at.bitfire.davdroid.resource
+
+import android.accounts.Account
+import android.accounts.AccountManager
+import android.annotation.TargetApi
+import android.content.*
+import android.os.Build
+import android.os.Bundle
+import android.os.RemoteException
+import android.provider.ContactsContract
+import android.provider.ContactsContract.CommonDataKinds.GroupMembership
+import android.provider.ContactsContract.Groups
+import android.provider.ContactsContract.RawContacts
+import android.util.Base64
+import at.bitfire.davdroid.DavUtils
+import at.bitfire.davdroid.R
+import at.bitfire.davdroid.log.Logger
+import at.bitfire.davdroid.model.CollectionInfo
+import at.bitfire.vcard4android.*
+import java.io.ByteArrayOutputStream
+import java.io.FileNotFoundException
+import java.util.*
+import java.util.logging.Level
+
+/**
+ * A local address book. Requires an own Android account, because Android manages contacts per
+ * account and there is no such thing as "address books". So, DAVdroid creates a "DAVdroid
+ * address book" account for every CardDAV address book. These accounts are bound to a
+ * DAVdroid main account.
+ */
+class LocalAddressBook(
+        private val context: Context,
+        account: Account,
+        provider: ContentProviderClient?
+): AndroidAddressBook<LocalContact, LocalGroup>(account, provider, LocalContact.Factory, LocalGroup.Factory), LocalCollection<LocalResource> {
+
+    companion object {
+
+        val USER_DATA_MAIN_ACCOUNT_TYPE = "real_account_type"
+        val USER_DATA_MAIN_ACCOUNT_NAME = "real_account_name"
+        val USER_DATA_URL = "url"
+        val USER_DATA_READ_ONLY = "read_only"
+        val USER_DATA_CTAG = "ctag"
+
+        @JvmStatic
+        @Throws(ContactsStorageException::class)
+        fun create(context: Context, provider: ContentProviderClient, mainAccount: Account, info: CollectionInfo): LocalAddressBook {
+            val accountManager = AccountManager.get(context)
+
+            val account = Account(accountName(mainAccount, info), context.getString(R.string.account_type_address_book))
+            if (!accountManager.addAccountExplicitly(account, null, initialUserData(mainAccount, info.url)))
+                throw ContactsStorageException("Couldn't create address book account")
+
+            val addressBook = LocalAddressBook(context, account, provider)
+            ContentResolver.setSyncAutomatically(account, ContactsContract.AUTHORITY, true)
+
+            // set up Contacts Provider Settings
+            val values = ContentValues(2)
+            values.put(ContactsContract.Settings.SHOULD_SYNC, 1)
+            values.put(ContactsContract.Settings.UNGROUPED_VISIBLE, 1)
+            addressBook.updateSettings(values)
+
+            return addressBook
+        }
+
+        @JvmStatic
+        @Throws(ContactsStorageException::class)
+        fun find(context: Context, provider: ContentProviderClient, mainAccount: Account?): List<LocalAddressBook> {
+            val accountManager = AccountManager.get(context)
+
+            val result = LinkedList<LocalAddressBook>()
+            accountManager.getAccountsByType(context.getString(R.string.account_type_address_book))
+                    .map { LocalAddressBook(context, it, provider) }
+                    .filter { mainAccount == null || it.getMainAccount() == mainAccount }
+                    .forEach { result += it }
+
+            return result
+        }
+
+        @JvmStatic
+        fun accountName(mainAccount: Account, info: CollectionInfo): String {
+            val baos = ByteArrayOutputStream()
+            baos.write(info.url.hashCode())
+            val hash = Base64.encodeToString(baos.toByteArray(), Base64.NO_WRAP or Base64.NO_PADDING)
+
+            val sb = StringBuilder(if (info.displayName.isNullOrEmpty()) DavUtils.lastSegmentOfUrl(info.url) else info.displayName)
+            sb      .append(" (")
+                    .append(mainAccount.name)
+                    .append(" ")
+                    .append(hash)
+                    .append(")")
+            return sb.toString()
+        }
+
+        @JvmStatic
+        fun initialUserData(mainAccount: Account, url: String): Bundle {
+            val bundle = Bundle(3)
+            bundle.putString(USER_DATA_MAIN_ACCOUNT_NAME, mainAccount.name)
+            bundle.putString(USER_DATA_MAIN_ACCOUNT_TYPE, mainAccount.type)
+            bundle.putString(USER_DATA_URL, url)
+            return bundle
+        }
+
+    }
+
+    /**
+     * Whether contact groups (LocalGroup resources) are included in query results for
+     * {@link #getAll()}, {@link #getDeleted()}, {@link #getDirty()} and
+     * {@link #getWithoutFileName()}.
+     */
+    var includeGroups = true
+
+
+    /* operations on the collection (address book) itself */
+
+    @Throws(ContactsStorageException::class)
+    fun update(info: CollectionInfo) {
+        val newAccountName = accountName(getMainAccount(), info)
+
+        @TargetApi(Build.VERSION_CODES.LOLLIPOP)
+        if (account.name != newAccountName && Build.VERSION.SDK_INT >= 21) {
+            val accountManager = AccountManager.get(context)
+            val future = accountManager.renameAccount(account, newAccountName, {
+                try {
+                    // update raw contacts to new account name
+                    provider?.let { provider ->
+                        val values = ContentValues(1)
+                        values.put(RawContacts.ACCOUNT_NAME, newAccountName)
+                        provider.update(syncAdapterURI(RawContacts.CONTENT_URI), values, "${RawContacts.ACCOUNT_NAME}=?", arrayOf(account.name))
+                    }
+                } catch(e: RemoteException) {
+                    Logger.log.log(Level.WARNING, "Couldn't re-assign contacts to new account name", e)
+                }
+            }, null)
+            account = future.result
+        }
+
+        Constants.log.info("Address book read-only? = ${info.readOnly}")
+        setReadOnly(info.readOnly || info.forceReadOnly)
+
+        // make sure it will still be synchronized when contacts are updated
+        ContentResolver.setSyncAutomatically(account, ContactsContract.AUTHORITY, true)
+    }
+
+    @Throws(ContactsStorageException::class)
+    fun delete() {
+        val accountManager = AccountManager.get(context)
+        try {
+            if (Build.VERSION.SDK_INT >= 22)
+                accountManager.removeAccount(account, null, null, null)
+            else
+                @Suppress("deprecation")
+                accountManager.removeAccount(account, null, null)
+        } catch(e: Exception) {
+            throw ContactsStorageException("Couldn't remove address book", e)
+        }
+    }
+
+
+    /* operations on members (contacts/groups) */
+
+    @Throws(ContactsStorageException::class, FileNotFoundException::class)
+    fun findContactByUID(uid: String): LocalContact {
+        val contacts = queryContacts("${AndroidContact.COLUMN_UID}=?", arrayOf(uid))
+        if (contacts.isEmpty())
+            throw FileNotFoundException()
+        return contacts.first()
+    }
+
+    @Throws(ContactsStorageException::class)
+    override fun getAll(): List<LocalResource> {
+        val all = LinkedList<LocalResource>()
+        all.addAll(queryContacts(null, null))
+        if (includeGroups)
+            all.addAll(queryGroups(null, null))
+        return all
+    }
+
+    /**
+     * Returns an array of local contacts/groups which have been deleted locally. (DELETED != 0).
+     */
+    @Throws(ContactsStorageException::class)
+    override fun getDeleted(): List<LocalResource> {
+        val deleted = LinkedList<LocalResource>()
+        deleted.addAll(getDeletedContacts())
+        if (includeGroups)
+            deleted.addAll(getDeletedGroups())
+        return deleted
+    }
+
+    /**
+     * Queries all contacts with DIRTY flag and checks whether their data checksum has changed, i.e.
+     * if they're "really dirty" (= data has changed, not only metadata, which is not hashed).
+     * The DIRTY flag is removed from contacts which are not "really dirty", i.e. from contacts
+     * whose contact data checksum has not changed.
+     * @return number of "really dirty" contacts
+     */
+    @Throws(ContactsStorageException::class)
+    fun verifyDirty(): Int {
+        if (Build.VERSION.SDK_INT < Build.VERSION_CODES.N || Build.VERSION.SDK_INT >= Build.VERSION_CODES.O)
+            throw IllegalStateException("verifyDirty() should not be called on Android != 7")
+
+        var reallyDirty = 0
+        for (contact in getDirtyContacts())
+            try {
+                val lastHash = contact.getLastHashCode()
+                val currentHash = contact.dataHashCode()
+                if (lastHash == currentHash) {
+                    // hash is code still the same, contact is not "really dirty" (only metadata been have changed)
+                    Logger.log.log(Level.FINE, "Contact data hash has not changed, resetting dirty flag", contact)
+                    contact.resetDirty()
+                } else {
+                    Logger.log.log(Level.FINE, "Contact data has changed from hash $lastHash to $currentHash", contact)
+                    reallyDirty++
+                }
+            } catch(e: FileNotFoundException) {
+                throw ContactsStorageException("Couldn't calculate hash code", e)
+            }
+
+        if (includeGroups)
+            reallyDirty += getDirtyGroups().size
+
+        return reallyDirty
+    }
+
+    /**
+     * Returns an array of local contacts/groups which have been changed locally (DIRTY != 0).
+     */
+    @Throws(ContactsStorageException::class)
+    override fun getDirty(): List<LocalResource> {
+        val dirty = LinkedList<LocalResource>()
+        dirty.addAll(getDirtyContacts())
+        if (includeGroups)
+            dirty.addAll(getDirtyGroups())
+        return dirty
+    }
+
+    /**
+     * Returns an array of local contacts which don't have a file name yet.
+     */
+    @Throws(ContactsStorageException::class)
+    override fun getWithoutFileName(): List<LocalResource> {
+        val nameless = LinkedList<LocalResource>()
+        nameless.addAll(queryContacts("${AndroidContact.COLUMN_FILENAME} IS NULL", null))
+        if (includeGroups)
+            nameless.addAll(queryGroups("${AndroidGroup.COLUMN_FILENAME} IS NULL", null))
+        return nameless
+    }
+
+    @Throws(ContactsStorageException::class)
+    fun getDeletedContacts() = queryContacts("${RawContacts.DELETED} != 0", null)
+
+    @Throws(ContactsStorageException::class)
+    fun getDirtyContacts() = queryContacts("${RawContacts.DIRTY} != 0", null)
+
+    @Throws(ContactsStorageException::class)
+    fun getDeletedGroups() = queryGroups("${Groups.DELETED} != 0", null)
+
+    @Throws(ContactsStorageException::class)
+    fun getDirtyGroups() = queryGroups("${Groups.DIRTY} != 0", null)
+
+    @Throws(ContactsStorageException::class)
+    fun getByGroupMembership(groupID: Long): List<LocalContact> {
+        try {
+            val ids = HashSet<Long>()
+
+            provider!!.query(syncAdapterURI(ContactsContract.Data.CONTENT_URI),
+                    arrayOf(RawContacts.Data.RAW_CONTACT_ID),
+                    "(${GroupMembership.MIMETYPE}=? AND ${GroupMembership.GROUP_ROW_ID}=?) OR (${CachedGroupMembership.MIMETYPE}=? AND ${CachedGroupMembership.GROUP_ID}=?)",
+                    arrayOf(GroupMembership.CONTENT_ITEM_TYPE, groupID.toString(), CachedGroupMembership.CONTENT_ITEM_TYPE, groupID.toString()),
+                    null)?.use { cursor ->
+                while (cursor.moveToNext())
+                    ids += cursor.getLong(0)
+            }
+
+            return ids.map { id -> LocalContact(this, id, null, null) }
+        } catch (e: RemoteException) {
+            throw ContactsStorageException("Couldn't query contacts", e)
+        }
+    }
+
+
+    /* special group operations */
+
+    /**
+     * Finds the first group with the given title. If there is no group with this
+     * title, a new group is created.
+     * @param title     title of the group to look for
+     * @return          id of the group with given title
+     * @throws ContactsStorageException on contact provider errors
+     */
+    @Throws(ContactsStorageException::class)
+    fun findOrCreateGroup(title: String): Long {
+        try {
+            provider!!.query(syncAdapterURI(Groups.CONTENT_URI), arrayOf(Groups._ID),
+                    "${Groups.TITLE}=?", arrayOf(title), null)?.use { cursor ->
+                if (cursor.moveToNext())
+                    return cursor.getLong(0)
+            }
+
+            val values = ContentValues(1)
+            values.put(Groups.TITLE, title)
+            val uri = provider.insert(syncAdapterURI(Groups.CONTENT_URI), values)
+            return ContentUris.parseId(uri)
+        } catch(e: RemoteException) {
+            throw ContactsStorageException("Couldn't find local contact group", e)
+        }
+    }
+
+    @Throws(ContactsStorageException::class)
+    fun removeEmptyGroups() {
+        // find groups without members
+        /** should be done using {@link Groups.SUMMARY_COUNT}, but it's not implemented in Android yet */
+        queryGroups(null, null).filter { it.getMembers().isEmpty() }.forEach { group ->
+            Logger.log.log(Level.FINE, "Deleting group", group)
+            group.delete()
+        }
+    }
+
+
+    // SETTINGS
+
+    @Throws(ContactsStorageException::class)
+    fun getMainAccount(): Account {
+        val accountManager = AccountManager.get(context)
+        val name = accountManager.getUserData(account, USER_DATA_MAIN_ACCOUNT_NAME)
+        val type = accountManager.getUserData(account, USER_DATA_MAIN_ACCOUNT_TYPE)
+        if (name != null && type != null)
+            return Account(name, type)
+        else
+            throw ContactsStorageException("Address book doesn't exist anymore")
+    }
+
+    fun setMainAccount(mainAccount: Account) {
+        val accountManager = AccountManager.get(context)
+        accountManager.setUserData(account, USER_DATA_MAIN_ACCOUNT_NAME, mainAccount.name)
+        accountManager.setUserData(account, USER_DATA_MAIN_ACCOUNT_TYPE, mainAccount.type)
+    }
+
+    @Throws(ContactsStorageException::class)
+    fun getURL() =
+            AccountManager.get(context).getUserData(account, USER_DATA_URL) ?: throw ContactsStorageException("Address book has no URL")
+
+    fun setURL(url: String) =
+            AccountManager.get(context).setUserData(account, USER_DATA_URL, url)
+
+    fun getReadOnly() =
+            AccountManager.get(context).getUserData(account, USER_DATA_READ_ONLY) != null
+
+    fun setReadOnly(readOnly: Boolean) =
+            AccountManager.get(context).setUserData(account, USER_DATA_READ_ONLY, if (readOnly) "1" else null)
+
+    override fun getCTag(): String? =
+            AccountManager.get(context).getUserData(account, USER_DATA_CTAG)
+
+    override fun setCTag(cTag: String?) =
+            AccountManager.get(context).setUserData(account, USER_DATA_CTAG, cTag)
+
+}

app/src/main/java/at/bitfire/davdroid/resource/LocalCalendar.java

@@ -1,254 +0,0 @@
-/*
- * Copyright © 2013 – 2015 Ricki Hirner (bitfire web engineering).
- * All rights reserved. This program and the accompanying materials
- * are made available under the terms of the GNU Public License v3.0
- * which accompanies this distribution, and is available at
- * http://www.gnu.org/licenses/gpl.html
- */
-
-package at.bitfire.davdroid.resource;
-
-import android.accounts.Account;
-import android.content.ContentProviderClient;
-import android.content.ContentProviderOperation;
-import android.content.ContentUris;
-import android.content.ContentValues;
-import android.database.Cursor;
-import android.net.Uri;
-import android.os.Build;
-import android.os.RemoteException;
-import android.provider.CalendarContract;
-import android.provider.CalendarContract.Calendars;
-import android.provider.CalendarContract.Events;
-import android.provider.CalendarContract.Reminders;
-import android.support.annotation.NonNull;
-import android.text.TextUtils;
-
-import net.fortuna.ical4j.model.component.VTimeZone;
-
-import org.apache.commons.lang3.StringUtils;
-
-import java.io.FileNotFoundException;
-import java.util.Collections;
-import java.util.LinkedList;
-import java.util.List;
-
-import at.bitfire.davdroid.App;
-import at.bitfire.davdroid.model.CollectionInfo;
-import at.bitfire.ical4android.AndroidCalendar;
-import at.bitfire.ical4android.AndroidCalendarFactory;
-import at.bitfire.ical4android.BatchOperation;
-import at.bitfire.ical4android.CalendarStorageException;
-import at.bitfire.ical4android.DateUtils;
-import at.bitfire.vcard4android.ContactsStorageException;
-import lombok.Cleanup;
-
-public class LocalCalendar extends AndroidCalendar implements LocalCollection {
-
-    public static final int defaultColor = 0xFF8bc34a;     // light green 500
-
-    public static final String COLUMN_CTAG = Calendars.CAL_SYNC1;
-
-    protected static final int
-            DIRTY_INCREASE_SEQUENCE = 1,
-            DIRTY_DONT_INCREASE_SEQUENCE = 2;
-
-    static String[] BASE_INFO_COLUMNS = new String[] {
-            Events._ID,
-            Events._SYNC_ID,
-            LocalEvent.COLUMN_ETAG
-    };
-
-    @Override
-    protected String[] eventBaseInfoColumns() {
-        return BASE_INFO_COLUMNS;
-    }
-
-
-    protected LocalCalendar(Account account, ContentProviderClient provider, long id) {
-        super(account, provider, LocalEvent.Factory.INSTANCE, id);
-    }
-
-    public static Uri create(@NonNull Account account, @NonNull ContentProviderClient provider, @NonNull CollectionInfo info) throws CalendarStorageException {
-        ContentValues values = valuesFromCollectionInfo(info);
-        values.put(Calendars.OWNER_ACCOUNT, account.name);
-        return create(account, provider, values);
-    }
-
-    public void update(CollectionInfo info) throws CalendarStorageException {
-        update(valuesFromCollectionInfo(info));
-    }
-
-    private static ContentValues valuesFromCollectionInfo(CollectionInfo info) {
-        ContentValues values = new ContentValues();
-        values.put(Calendars.NAME, info.url);
-        values.put(Calendars.CALENDAR_DISPLAY_NAME, info.displayName);
-        values.put(Calendars.CALENDAR_COLOR, info.color != null ? info.color : defaultColor);
-
-        if (info.readOnly)
-            values.put(Calendars.CALENDAR_ACCESS_LEVEL, Calendars.CAL_ACCESS_READ);
-        else {
-            values.put(Calendars.CALENDAR_ACCESS_LEVEL, Calendars.CAL_ACCESS_OWNER);
-            values.put(Calendars.CAN_MODIFY_TIME_ZONE, 1);
-            values.put(Calendars.CAN_ORGANIZER_RESPOND, 1);
-        }
-
-        values.put(Calendars.SYNC_EVENTS, 1);
-        values.put(Calendars.VISIBLE, 1);
-        if (!TextUtils.isEmpty(info.timeZone)) {
-            VTimeZone timeZone = DateUtils.parseVTimeZone(info.timeZone);
-            if (timeZone != null && timeZone.getTimeZoneId() != null)
-                values.put(Calendars.CALENDAR_TIME_ZONE, DateUtils.findAndroidTimezoneID(timeZone.getTimeZoneId().getValue()));
-        }
-        values.put(Calendars.ALLOWED_REMINDERS, Reminders.METHOD_ALERT);
-        if (Build.VERSION.SDK_INT >= 15) {
-            values.put(Calendars.ALLOWED_AVAILABILITY, StringUtils.join(new int[] { Reminders.AVAILABILITY_TENTATIVE, Reminders.AVAILABILITY_FREE, Reminders.AVAILABILITY_BUSY }, ","));
-            values.put(Calendars.ALLOWED_ATTENDEE_TYPES, StringUtils.join(new int[] { CalendarContract.Attendees.TYPE_OPTIONAL, CalendarContract.Attendees.TYPE_REQUIRED, CalendarContract.Attendees.TYPE_RESOURCE }, ", "));
-        }
-        return values;
-    }
-
-
-    @Override
-    public LocalResource[] getAll() throws CalendarStorageException, ContactsStorageException {
-        return (LocalEvent[])queryEvents(Events.ORIGINAL_ID + " IS NULL", null);
-    }
-
-    @Override
-    public LocalEvent[] getDeleted() throws CalendarStorageException {
-        return (LocalEvent[])queryEvents(Events.DELETED + "!=0 AND " + Events.ORIGINAL_ID + " IS NULL", null);
-    }
-
-    @Override
-    public LocalEvent[] getWithoutFileName() throws CalendarStorageException {
-        return (LocalEvent[])queryEvents(Events._SYNC_ID + " IS NULL AND " + Events.ORIGINAL_ID + " IS NULL", null);
-    }
-
-    @Override
-    public LocalResource[] getDirty() throws CalendarStorageException, FileNotFoundException {
-        List<LocalResource> dirty = new LinkedList<>();
-
-        // get dirty events which are not required to have an increased SEQUENCE value
-        Collections.addAll(dirty, (LocalEvent[])queryEvents(Events.DIRTY + "=" + DIRTY_DONT_INCREASE_SEQUENCE + " AND " + Events.ORIGINAL_ID + " IS NULL", null));
-
-        // get dirty events which are required to have an increased SEQUENCE value
-        for (LocalEvent event : (LocalEvent[])queryEvents(Events.DIRTY + "=" + DIRTY_INCREASE_SEQUENCE + " AND " + Events.ORIGINAL_ID + " IS NULL", null)) {
-            if (event.getEvent().sequence == null)      // sequence has not been assigned yet (i.e. this event was just locally created)
-                event.getEvent().sequence = 0;
-            else
-                event.getEvent().sequence++;
-            dirty.add(event);
-        }
-
-        return dirty.toArray(new LocalResource[dirty.size()]);
-    }
-
-
-    @Override
-    @SuppressWarnings("Recycle")
-    public String getCTag() throws CalendarStorageException {
-        try {
-            @Cleanup Cursor cursor = provider.query(calendarSyncURI(), new String[] { COLUMN_CTAG }, null, null, null);
-            if (cursor != null && cursor.moveToNext())
-                return cursor.getString(0);
-        } catch (RemoteException e) {
-            throw new CalendarStorageException("Couldn't read local (last known) CTag", e);
-        }
-        return null;
-    }
-
-    @Override
-    public void setCTag(String cTag) throws CalendarStorageException, ContactsStorageException {
-        try {
-            ContentValues values = new ContentValues(1);
-            values.put(COLUMN_CTAG, cTag);
-            provider.update(calendarSyncURI(), values, null, null);
-        } catch (RemoteException e) {
-            throw new CalendarStorageException("Couldn't write local (last known) CTag", e);
-        }
-    }
-
-    @SuppressWarnings("Recycle")
-    public void processDirtyExceptions() throws CalendarStorageException {
-        // process deleted exceptions
-        App.log.info("Processing deleted exceptions");
-        try {
-            @Cleanup Cursor cursor = provider.query(
-                    syncAdapterURI(Events.CONTENT_URI),
-                    new String[] { Events._ID, Events.ORIGINAL_ID, LocalEvent.COLUMN_SEQUENCE },
-                    Events.DELETED + "!=0 AND " + Events.ORIGINAL_ID + " IS NOT NULL", null, null);
-            while (cursor != null && cursor.moveToNext()) {
-                App.log.fine("Found deleted exception, removing; then re-schuling original event");
-                long    id = cursor.getLong(0),             // can't be null (by definition)
-                        originalID = cursor.getLong(1);     // can't be null (by query)
-
-                // get original event's SEQUENCE
-                @Cleanup Cursor cursor2 = provider.query(
-                        syncAdapterURI(ContentUris.withAppendedId(Events.CONTENT_URI, originalID)),
-                        new String[] { LocalEvent.COLUMN_SEQUENCE },
-                        null, null, null);
-                int originalSequence = (cursor2 == null || cursor2.isNull(0)) ? 0 : cursor2.getInt(0);
-
-                BatchOperation batch = new BatchOperation(provider);
-                // re-schedule original event and set it to DIRTY
-                batch.enqueue(ContentProviderOperation.newUpdate(
-                        syncAdapterURI(ContentUris.withAppendedId(Events.CONTENT_URI, originalID)))
-                        .withValue(LocalEvent.COLUMN_SEQUENCE, originalSequence + 1)
-                        .withValue(Events.DIRTY, DIRTY_INCREASE_SEQUENCE)
-                        .build());
-                // remove exception
-                batch.enqueue(ContentProviderOperation.newDelete(
-                        syncAdapterURI(ContentUris.withAppendedId(Events.CONTENT_URI, id))).build());
-                batch.commit();
-            }
-        } catch (RemoteException e) {
-            throw new CalendarStorageException("Couldn't process locally modified exception", e);
-        }
-
-        // process dirty exceptions
-        App.log.info("Processing dirty exceptions");
-        try {
-            @Cleanup Cursor cursor = provider.query(
-                    syncAdapterURI(Events.CONTENT_URI),
-                    new String[] { Events._ID, Events.ORIGINAL_ID, LocalEvent.COLUMN_SEQUENCE },
-                    Events.DIRTY + "!=0 AND " + Events.ORIGINAL_ID + " IS NOT NULL", null, null);
-            while (cursor != null && cursor.moveToNext()) {
-                App.log.fine("Found dirty exception, increasing SEQUENCE to re-schedule");
-                long    id = cursor.getLong(0),             // can't be null (by definition)
-                        originalID = cursor.getLong(1);     // can't be null (by query)
-                int sequence = cursor.isNull(2) ? 0 : cursor.getInt(2);
-
-                BatchOperation batch = new BatchOperation(provider);
-                // original event to DIRTY
-                batch.enqueue(ContentProviderOperation.newUpdate(
-                        syncAdapterURI(ContentUris.withAppendedId(Events.CONTENT_URI, originalID)))
-                        .withValue(Events.DIRTY, DIRTY_DONT_INCREASE_SEQUENCE)
-                        .build());
-                // increase SEQUENCE and set DIRTY to 0
-                batch.enqueue(ContentProviderOperation.newUpdate(
-                                syncAdapterURI(ContentUris.withAppendedId(Events.CONTENT_URI, id)))
-                                .withValue(LocalEvent.COLUMN_SEQUENCE, sequence + 1)
-                                .withValue(Events.DIRTY, 0)
-                                .build());
-                batch.commit();
-            }
-        } catch (RemoteException e) {
-            throw new CalendarStorageException("Couldn't process locally modified exception", e);
-        }
-    }
-
-
-    public static class Factory implements AndroidCalendarFactory {
-        public static final Factory INSTANCE = new Factory();
-
-        @Override
-        public AndroidCalendar newInstance(Account account, ContentProviderClient provider, long id) {
-            return new LocalCalendar(account, provider, id);
-        }
-
-        @Override
-        public AndroidCalendar[] newArray(int size) {
-            return new LocalCalendar[size];
-        }
-    }
-}

app/src/main/java/at/bitfire/davdroid/resource/LocalCalendar.kt

@@ -0,0 +1,236 @@
+/*
+ * Copyright © Ricki Hirner (bitfire web engineering).
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the GNU Public License v3.0
+ * which accompanies this distribution, and is available at
+ * http://www.gnu.org/licenses/gpl.html
+ */
+
+package at.bitfire.davdroid.resource
+
+import android.accounts.Account
+import android.content.ContentProviderClient
+import android.content.ContentProviderOperation
+import android.content.ContentUris
+import android.content.ContentValues
+import android.net.Uri
+import android.os.RemoteException
+import android.provider.CalendarContract
+import android.provider.CalendarContract.*
+import at.bitfire.davdroid.DavUtils
+import at.bitfire.davdroid.log.Logger
+import at.bitfire.davdroid.model.CollectionInfo
+import at.bitfire.ical4android.*
+import java.io.FileNotFoundException
+import java.util.*
+import java.util.logging.Level
+
+class LocalCalendar private constructor(
+        account: Account,
+        provider: ContentProviderClient,
+        id: Long
+): AndroidCalendar<LocalEvent>(account, provider, LocalEvent.Factory, id), LocalCollection<LocalEvent> {
+
+    companion object {
+
+        val defaultColor = 0xFF8bc34a.toInt()     // light green 500
+
+        val COLUMN_CTAG = Calendars.CAL_SYNC1
+
+        val BASE_INFO_COLUMNS = arrayOf(
+            Events._ID,
+            Events._SYNC_ID,
+            LocalEvent.COLUMN_ETAG
+        )
+
+
+        @Throws(CalendarStorageException::class)
+        fun create(account: Account, provider: ContentProviderClient, info: CollectionInfo): Uri {
+            val values = valuesFromCollectionInfo(info, true)
+
+            // ACCOUNT_NAME and ACCOUNT_TYPE are required (see docs)! If it's missing, other apps will crash.
+            values.put(Calendars.ACCOUNT_NAME, account.name)
+            values.put(Calendars.ACCOUNT_TYPE, account.type)
+            values.put(Calendars.OWNER_ACCOUNT, account.name)
+
+            // flag as visible & synchronizable at creation, might be changed by user at any time
+            values.put(Calendars.VISIBLE, 1)
+            values.put(Calendars.SYNC_EVENTS, 1)
+            return create(account, provider, values)
+        }
+
+        private fun valuesFromCollectionInfo(info: CollectionInfo, withColor: Boolean): ContentValues {
+            val values = ContentValues()
+            values.put(Calendars.NAME, info.url)
+            values.put(Calendars.CALENDAR_DISPLAY_NAME, if (info.displayName.isNullOrBlank()) DavUtils.lastSegmentOfUrl(info.url) else info.displayName)
+
+            if (withColor)
+                values.put(Calendars.CALENDAR_COLOR, info.color ?: defaultColor)
+
+            if (info.readOnly || info.forceReadOnly)
+                values.put(Calendars.CALENDAR_ACCESS_LEVEL, Calendars.CAL_ACCESS_READ)
+            else {
+                values.put(Calendars.CALENDAR_ACCESS_LEVEL, Calendars.CAL_ACCESS_OWNER)
+                values.put(Calendars.CAN_MODIFY_TIME_ZONE, 1)
+                values.put(Calendars.CAN_ORGANIZER_RESPOND, 1)
+            }
+
+            info.timeZone?.let { tzData ->
+                try {
+                    val timeZone = DateUtils.parseVTimeZone(tzData)
+                    timeZone.timeZoneId?.let { tzId ->
+                        values.put(Calendars.CALENDAR_TIME_ZONE, DateUtils.findAndroidTimezoneID(tzId.value))
+                    }
+                } catch(e: IllegalArgumentException) {
+                    Logger.log.log(Level.WARNING, "Couldn't parse calendar default time zone", e)
+                }
+            }
+            values.put(Calendars.ALLOWED_REMINDERS, "${Reminders.METHOD_ALERT},${Reminders.METHOD_EMAIL}")
+            values.put(Calendars.ALLOWED_AVAILABILITY, "${Reminders.AVAILABILITY_TENTATIVE},${Reminders.AVAILABILITY_FREE},${Reminders.AVAILABILITY_BUSY}")
+            values.put(Calendars.ALLOWED_ATTENDEE_TYPES, "${CalendarContract.Attendees.TYPE_OPTIONAL},${CalendarContract.Attendees.TYPE_REQUIRED},${CalendarContract.Attendees.TYPE_RESOURCE}")
+            return values
+        }
+
+    }
+
+
+    override fun eventBaseInfoColumns() = BASE_INFO_COLUMNS
+
+
+    @Throws(CalendarStorageException::class)
+    fun update(info: CollectionInfo, updateColor: Boolean) =
+            update(valuesFromCollectionInfo(info, updateColor))
+
+    @Throws(CalendarStorageException::class)
+    override fun getAll(): List<LocalEvent> =
+            queryEvents("${Events.ORIGINAL_ID} IS NULL", null)
+
+    @Throws(CalendarStorageException::class)
+    override fun getDeleted() =
+            queryEvents("${Events.DELETED}!=0 AND ${Events.ORIGINAL_ID} IS NULL", null)
+
+    @Throws(CalendarStorageException::class)
+    override fun getWithoutFileName() =
+            queryEvents("${Events._SYNC_ID} IS NULL AND ${Events.ORIGINAL_ID} IS NULL", null)
+
+    @Throws(FileNotFoundException::class, CalendarStorageException::class)
+    override fun getDirty(): List<LocalEvent> {
+        val dirty = LinkedList<LocalEvent>()
+
+        // get dirty events which are required to have an increased SEQUENCE value
+        for (localEvent in queryEvents("${Events.DIRTY}!=0 AND ${Events.ORIGINAL_ID} IS NULL", null)) {
+            val event = localEvent.event!!
+            val sequence = event.sequence
+            if (event.sequence == null)      // sequence has not been assigned yet (i.e. this event was just locally created)
+                event.sequence = 0
+            else if (localEvent.weAreOrganizer)
+                event.sequence = sequence!! + 1
+            dirty += localEvent
+        }
+
+        return dirty
+    }
+
+    @Throws(CalendarStorageException::class)
+    override fun getCTag(): String? =
+        try {
+            provider.query(calendarSyncURI(), arrayOf(COLUMN_CTAG), null, null, null)?.use { cursor ->
+                if (cursor.moveToNext())
+                    return cursor.getString(0)
+            }
+            null
+        } catch (e: RemoteException) {
+            throw CalendarStorageException("Couldn't read local (last known) CTag", e)
+        }
+
+    @Throws(CalendarStorageException::class)
+    override fun setCTag(cTag: String?) {
+        try {
+            val values = ContentValues(1)
+            values.put(COLUMN_CTAG, cTag)
+            provider.update(calendarSyncURI(), values, null, null)
+        } catch (e: RemoteException) {
+            throw CalendarStorageException("Couldn't write local (last known) CTag", e)
+        }
+    }
+
+    @Throws(CalendarStorageException::class)
+    fun processDirtyExceptions() {
+        try {
+            // process deleted exceptions
+            Logger.log.info("Processing deleted exceptions")
+            provider.query(
+                    syncAdapterURI(Events.CONTENT_URI),
+                    arrayOf(Events._ID, Events.ORIGINAL_ID, LocalEvent.COLUMN_SEQUENCE),
+                    "${Events.DELETED}!=0 AND ${Events.ORIGINAL_ID} IS NOT NULL", null, null)?.use { cursor ->
+                while (cursor.moveToNext()) {
+                    Logger.log.fine("Found deleted exception, removing; then re-scheduling original event")
+                    val id = cursor.getLong(0)             // can't be null (by definition)
+                    val originalID = cursor.getLong(1)     // can't be null (by query)
+
+                    val batch = BatchOperation(provider)
+
+                    // get original event's SEQUENCE
+                    provider.query(
+                            syncAdapterURI(ContentUris.withAppendedId(Events.CONTENT_URI, originalID)),
+                            arrayOf(LocalEvent.COLUMN_SEQUENCE),
+                            null, null, null)?.use { cursor2 ->
+                        val originalSequence = if (cursor2.isNull(0)) 0 else cursor2.getInt(0)
+
+                        // re-schedule original event and set it to DIRTY
+                        batch.enqueue(BatchOperation.Operation(
+                                ContentProviderOperation.newUpdate(syncAdapterURI(ContentUris.withAppendedId(Events.CONTENT_URI, originalID)))
+                                        .withValue(LocalEvent.COLUMN_SEQUENCE, originalSequence + 1)
+                                        .withValue(Events.DIRTY, 1)
+                        ))
+                    }
+
+                    // remove exception
+                    batch.enqueue(BatchOperation.Operation(
+                            ContentProviderOperation.newDelete(syncAdapterURI(ContentUris.withAppendedId(Events.CONTENT_URI, id)))
+                    ))
+                    batch.commit()
+                }
+            }
+
+            // process dirty exceptions
+            Logger.log.info("Processing dirty exceptions")
+            provider.query(
+                    syncAdapterURI(Events.CONTENT_URI),
+                    arrayOf(Events._ID, Events.ORIGINAL_ID, LocalEvent.COLUMN_SEQUENCE),
+                    "${Events.DIRTY}!=0 AND ${Events.ORIGINAL_ID} IS NOT NULL", null, null)?.use { cursor ->
+                while (cursor.moveToNext()) {
+                    Logger.log.fine("Found dirty exception, increasing SEQUENCE to re-schedule")
+                    val id = cursor.getLong(0)             // can't be null (by definition)
+                    val originalID = cursor.getLong(1)     // can't be null (by query)
+                    val sequence = if (cursor.isNull(2)) 0 else cursor.getInt(2)
+
+                    val batch = BatchOperation(provider)
+                    // original event to DIRTY
+                    batch.enqueue(BatchOperation.Operation (
+                            ContentProviderOperation.newUpdate(syncAdapterURI(ContentUris.withAppendedId(Events.CONTENT_URI, originalID)))
+                                    .withValue(Events.DIRTY, 1)
+                    ))
+                    // increase SEQUENCE and set DIRTY to 0
+                    batch.enqueue(BatchOperation.Operation (
+                            ContentProviderOperation.newUpdate(syncAdapterURI(ContentUris.withAppendedId(Events.CONTENT_URI, id)))
+                                    .withValue(LocalEvent.COLUMN_SEQUENCE, sequence + 1)
+                                    .withValue(Events.DIRTY, 0)
+                    ))
+                    batch.commit()
+                }
+            }
+        } catch (e: RemoteException) {
+            throw CalendarStorageException("Couldn't process locally modified exception", e)
+        }
+    }
+
+
+    object Factory: AndroidCalendarFactory<LocalCalendar> {
+
+        override fun newInstance(account: Account, provider: ContentProviderClient, id: Long) =
+            LocalCalendar(account, provider, id)
+
+    }
+
+}

app/src/main/java/at/bitfire/davdroid/resource/LocalCollection.java

@@ -1,26 +0,0 @@
-/*
- * Copyright © 2013 – 2015 Ricki Hirner (bitfire web engineering).
- * All rights reserved. This program and the accompanying materials
- * are made available under the terms of the GNU Public License v3.0
- * which accompanies this distribution, and is available at
- * http://www.gnu.org/licenses/gpl.html
- */
-
-package at.bitfire.davdroid.resource;
-
-import java.io.FileNotFoundException;
-
-import at.bitfire.ical4android.CalendarStorageException;
-import at.bitfire.vcard4android.ContactsStorageException;
-
-public interface LocalCollection {
-
-    LocalResource[] getDeleted() throws CalendarStorageException, ContactsStorageException;
-    LocalResource[] getWithoutFileName()  throws CalendarStorageException, ContactsStorageException;
-    LocalResource[] getDirty() throws CalendarStorageException, ContactsStorageException, FileNotFoundException;
-
-    LocalResource[] getAll() throws CalendarStorageException, ContactsStorageException;
-
-    String getCTag() throws CalendarStorageException, ContactsStorageException;
-    void setCTag(String cTag) throws CalendarStorageException, ContactsStorageException;
-}

app/src/main/java/at/bitfire/davdroid/resource/LocalCollection.kt

@@ -0,0 +1,35 @@
+/*
+ * Copyright © Ricki Hirner (bitfire web engineering).
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the GNU Public License v3.0
+ * which accompanies this distribution, and is available at
+ * http://www.gnu.org/licenses/gpl.html
+ */
+
+package at.bitfire.davdroid.resource
+
+import at.bitfire.ical4android.CalendarStorageException
+import at.bitfire.vcard4android.ContactsStorageException
+import java.io.FileNotFoundException
+
+interface LocalCollection<out T: LocalResource> {
+
+    @Throws(CalendarStorageException::class, ContactsStorageException::class)
+    fun getDeleted(): List<T>
+
+    @Throws(CalendarStorageException::class, ContactsStorageException::class)
+    fun getWithoutFileName(): List<T>
+
+    @Throws(CalendarStorageException::class, ContactsStorageException::class, FileNotFoundException::class)
+    fun getDirty(): List<T>
+
+    @Throws(CalendarStorageException::class, ContactsStorageException::class)
+    fun getAll(): List<T>
+
+    @Throws(CalendarStorageException::class, ContactsStorageException::class)
+    fun getCTag(): String?
+
+    @Throws(CalendarStorageException::class, ContactsStorageException::class)
+    fun setCTag(cTag: String?)
+
+}

app/src/main/java/at/bitfire/davdroid/resource/LocalContact.java

@@ -1,143 +0,0 @@
-/*
- * Copyright © 2013 – 2015 Ricki Hirner (bitfire web engineering).
- * All rights reserved. This program and the accompanying materials
- * are made available under the terms of the GNU Public License v3.0
- * which accompanies this distribution, and is available at
- * http://www.gnu.org/licenses/gpl.html
- */
-
-package at.bitfire.davdroid.resource;
-
-import android.content.ContentProviderOperation;
-import android.content.ContentValues;
-import android.os.RemoteException;
-import android.provider.ContactsContract;
-import android.provider.ContactsContract.CommonDataKinds.GroupMembership;
-
-import java.io.FileNotFoundException;
-import java.util.logging.Level;
-
-import at.bitfire.davdroid.App;
-import at.bitfire.davdroid.BuildConfig;
-import at.bitfire.vcard4android.AndroidAddressBook;
-import at.bitfire.vcard4android.AndroidContact;
-import at.bitfire.vcard4android.AndroidContactFactory;
-import at.bitfire.vcard4android.BatchOperation;
-import at.bitfire.vcard4android.Contact;
-import at.bitfire.vcard4android.ContactsStorageException;
-import ezvcard.Ezvcard;
-
-public class LocalContact extends AndroidContact implements LocalResource {
-    static {
-        Contact.productID = "+//IDN bitfire.at//DAVdroid/" + BuildConfig.VERSION_NAME + " vcard4android ez-vcard/" + Ezvcard.VERSION;
-    }
-
-    protected LocalContact(AndroidAddressBook addressBook, long id, String fileName, String eTag) {
-        super(addressBook, id, fileName, eTag);
-    }
-
-    public LocalContact(AndroidAddressBook addressBook, Contact contact, String fileName, String eTag) {
-        super(addressBook, contact, fileName, eTag);
-    }
-
-    public void clearDirty(String eTag) throws ContactsStorageException {
-        try {
-            ContentValues values = new ContentValues(1);
-            values.put(ContactsContract.RawContacts.DIRTY, 0);
-            values.put(COLUMN_ETAG, eTag);
-            addressBook.provider.update(rawContactSyncURI(), values, null, null);
-
-            this.eTag = eTag;
-        } catch (RemoteException e) {
-            throw new ContactsStorageException("Couldn't clear dirty flag", e);
-        }
-    }
-
-    public void updateFileNameAndUID(String uid) throws ContactsStorageException {
-        try {
-            String newFileName = uid + ".vcf";
-
-            ContentValues values = new ContentValues(2);
-            values.put(COLUMN_FILENAME, newFileName);
-            values.put(COLUMN_UID, uid);
-            addressBook.provider.update(rawContactSyncURI(), values, null, null);
-
-            fileName = newFileName;
-        } catch (RemoteException e) {
-            throw new ContactsStorageException("Couldn't update UID", e);
-        }
-    }
-
-
-    // group support
-
-    @Override
-    protected void populateGroupMembership(ContentValues row) {
-        if (row.containsKey(GroupMembership.GROUP_ROW_ID)) {
-            long groupId = row.getAsLong(GroupMembership.GROUP_ROW_ID);
-
-            // fetch group
-            LocalGroup group = new LocalGroup(addressBook, groupId);
-            try {
-                Contact groupInfo = group.getContact();
-
-                // add to CATEGORIES
-                contact.getCategories().add(groupInfo.displayName);
-            } catch (FileNotFoundException|ContactsStorageException e) {
-                App.log.log(Level.WARNING, "Couldn't find assigned group #" + groupId + ", ignoring membership", e);
-            }
-        }
-    }
-
-    @Override
-    protected void insertGroupMemberships(BatchOperation batch) throws ContactsStorageException {
-        for (String category : contact.getCategories()) {
-            // Is there already a category with this display name?
-            LocalGroup group = ((LocalAddressBook)addressBook).findGroupByTitle(category);
-
-            if (group == null) {
-                // no, we have to create the group before inserting the membership
-
-                Contact groupInfo = new Contact();
-                groupInfo.displayName = category;
-                group = new LocalGroup(addressBook, groupInfo);
-                group.create();
-            }
-
-            Long groupId = group.getId();
-            if (groupId != null) {
-                ContentProviderOperation.Builder builder = ContentProviderOperation.newInsert(dataSyncURI());
-                if (id == null)
-                    builder.withValueBackReference(GroupMembership.RAW_CONTACT_ID, 0);
-                else
-                    builder.withValue(GroupMembership.RAW_CONTACT_ID, id);
-                builder .withValue(GroupMembership.MIMETYPE, GroupMembership.CONTENT_ITEM_TYPE)
-                        .withValue(GroupMembership.GROUP_ROW_ID, groupId);
-                batch.enqueue(builder.build());
-            }
-        }
-    }
-
-
-    // factory
-
-    static class Factory extends AndroidContactFactory {
-        static final Factory INSTANCE = new Factory();
-
-        @Override
-        public LocalContact newInstance(AndroidAddressBook addressBook, long id, String fileName, String eTag) {
-            return new LocalContact(addressBook, id, fileName, eTag);
-        }
-
-        @Override
-        public LocalContact newInstance(AndroidAddressBook addressBook, Contact contact, String fileName, String eTag) {
-            return new LocalContact(addressBook, contact, fileName, eTag);
-        }
-
-        public LocalContact[] newArray(int size) {
-            return new LocalContact[size];
-        }
-
-    }
-
-}

app/src/main/java/at/bitfire/davdroid/resource/LocalContact.kt

@@ -0,0 +1,284 @@
+/*
+ * Copyright © Ricki Hirner (bitfire web engineering).
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the GNU Public License v3.0
+ * which accompanies this distribution, and is available at
+ * http://www.gnu.org/licenses/gpl.html
+ */
+
+package at.bitfire.davdroid.resource
+
+import android.content.ContentProviderOperation
+import android.content.ContentValues
+import android.os.Build
+import android.os.RemoteException
+import android.provider.ContactsContract
+import android.provider.ContactsContract.CommonDataKinds.GroupMembership
+import android.provider.ContactsContract.RawContacts.Data
+import at.bitfire.davdroid.BuildConfig
+import at.bitfire.davdroid.log.Logger
+import at.bitfire.davdroid.model.UnknownProperties
+import at.bitfire.vcard4android.*
+import ezvcard.Ezvcard
+import java.io.FileNotFoundException
+import java.util.*
+
+class LocalContact: AndroidContact, LocalResource {
+
+    companion object {
+
+        init {
+            Contact.productID = "+//IDN bitfire.at//DAVdroid/" + BuildConfig.VERSION_NAME + " ez-vcard/" + Ezvcard.VERSION
+        }
+
+        val COLUMN_HASHCODE = ContactsContract.RawContacts.SYNC3
+
+    }
+
+    private val cachedGroupMemberships = HashSet<Long>()
+    private val groupMemberships = HashSet<Long>()
+
+
+    constructor(addressBook: AndroidAddressBook<LocalContact,*>, id: Long, fileName: String?, eTag: String?):
+            super(addressBook, id, fileName, eTag)
+
+    constructor(addressBook: AndroidAddressBook<LocalContact,*>, contact: Contact, fileName: String?, eTag: String?):
+            super(addressBook, contact, fileName, eTag)
+
+
+    @Throws(ContactsStorageException::class)
+    fun resetDeleted() {
+        val values = ContentValues(1)
+        values.put(ContactsContract.RawContacts.DELETED, 0)
+        try {
+            addressBook.provider!!.update(rawContactSyncURI(), values, null, null)
+        } catch(e: RemoteException) {
+            throw ContactsStorageException("Couldn't clear deleted flag", e)
+        }
+    }
+
+    @Throws(ContactsStorageException::class)
+    fun resetDirty() {
+        val values = ContentValues(1)
+        values.put(ContactsContract.RawContacts.DIRTY, 0)
+        try {
+            addressBook.provider!!.update(rawContactSyncURI(), values, null, null)
+        } catch(e: RemoteException) {
+            throw ContactsStorageException("Couldn't clear dirty flag", e)
+        }
+    }
+
+    @Throws(ContactsStorageException::class)
+    override fun clearDirty(eTag: String?) {
+        try {
+            val values = ContentValues(3)
+            values.put(COLUMN_ETAG, eTag)
+            values.put(ContactsContract.RawContacts.DIRTY, 0)
+
+            if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.N && Build.VERSION.SDK_INT < Build.VERSION_CODES.O) {
+                // workaround for Android 7 which sets DIRTY flag when only meta-data is changed
+                val hashCode = dataHashCode()
+                values.put(COLUMN_HASHCODE, hashCode)
+                Logger.log.finer("Clearing dirty flag with eTag = $eTag, contact hash = $hashCode")
+            }
+
+            addressBook.provider!!.update(rawContactSyncURI(), values, null, null)
+
+            this.eTag = eTag
+        } catch(e: Exception) {
+            throw ContactsStorageException("Couldn't clear dirty flag", e)
+        }
+    }
+
+    @Throws(ContactsStorageException::class)
+    override fun prepareForUpload() {
+        try {
+            val uid = UUID.randomUUID().toString()
+            val newFileName = uid + ".vcf"
+
+            val values = ContentValues(2)
+            values.put(COLUMN_FILENAME, newFileName)
+            values.put(COLUMN_UID, uid)
+            addressBook.provider!!.update(rawContactSyncURI(), values, null, null)
+
+            fileName = newFileName
+        } catch(e: RemoteException) {
+            throw ContactsStorageException("Couldn't update UID", e)
+        }
+    }
+
+
+    @Throws(ContactsStorageException::class)
+    override fun populateData(mimeType: String, row: ContentValues) {
+        when (mimeType) {
+            CachedGroupMembership.CONTENT_ITEM_TYPE ->
+                cachedGroupMemberships.add(row.getAsLong(CachedGroupMembership.GROUP_ID))
+            GroupMembership.CONTENT_ITEM_TYPE ->
+                groupMemberships.add(row.getAsLong(GroupMembership.GROUP_ROW_ID))
+            UnknownProperties.CONTENT_ITEM_TYPE ->
+                try {
+                    contact!!.unknownProperties = row.getAsString(UnknownProperties.UNKNOWN_PROPERTIES)
+                } catch(e: FileNotFoundException) {
+                    throw ContactsStorageException("Couldn't fetch data rows", e)
+                }
+        }
+    }
+
+    @Throws(ContactsStorageException::class)
+    override fun insertDataRows(batch: BatchOperation) {
+        super.insertDataRows(batch)
+
+        try {
+            contact!!.unknownProperties?.let { unknownProperties ->
+                val op: BatchOperation.Operation
+                val builder = ContentProviderOperation.newInsert(dataSyncURI())
+                if (id == null)
+                    op = BatchOperation.Operation(builder, UnknownProperties.RAW_CONTACT_ID, 0)
+                else {
+                    op = BatchOperation.Operation(builder)
+                    builder.withValue(UnknownProperties.RAW_CONTACT_ID, id)
+                }
+                builder .withValue(UnknownProperties.MIMETYPE, UnknownProperties.CONTENT_ITEM_TYPE)
+                        .withValue(UnknownProperties.UNKNOWN_PROPERTIES, unknownProperties)
+                batch.enqueue(op)
+            }
+        } catch(e: FileNotFoundException) {
+            throw ContactsStorageException("Couldn't insert data rows", e)
+        }
+
+    }
+
+
+    /**
+     * Calculates a hash code from the contact's data (VCard) and group memberships.
+     * Attention: re-reads {@link #contact} from the database, discarding all changes in memory
+     * @return hash code of contact data (including group memberships)
+     */
+    @Throws(FileNotFoundException::class, ContactsStorageException::class)
+    internal fun dataHashCode(): Int {
+        if (Build.VERSION.SDK_INT < Build.VERSION_CODES.N || Build.VERSION.SDK_INT >= Build.VERSION_CODES.O)
+            throw IllegalStateException("dataHashCode() should not be called on Android != 7")
+
+        // reset contact so that getContact() reads from database
+        contact = null
+
+        // groupMemberships is filled by getContact()
+        val dataHash = contact!!.hashCode()
+        val groupHash = groupMemberships.hashCode()
+        Logger.log.finest("Calculated data hash = $dataHash, group memberships hash = $groupHash")
+        return dataHash xor groupHash
+    }
+
+    @Throws(ContactsStorageException::class)
+    fun updateHashCode(batch: BatchOperation?) {
+        if (Build.VERSION.SDK_INT < Build.VERSION_CODES.N || Build.VERSION.SDK_INT >= Build.VERSION_CODES.O)
+            throw IllegalStateException("updateHashCode() should not be called on Android != 7")
+
+        val values = ContentValues(1)
+        try {
+            val hashCode = dataHashCode()
+            Logger.log.fine("Storing contact hash = $hashCode")
+            values.put(COLUMN_HASHCODE, hashCode)
+
+            if (batch == null)
+                addressBook.provider!!.update(rawContactSyncURI(), values, null, null)
+            else {
+                val builder = ContentProviderOperation
+                        .newUpdate(rawContactSyncURI())
+                        .withValues(values)
+                batch.enqueue(BatchOperation.Operation(builder))
+            }
+        } catch(e: Exception) {
+            throw ContactsStorageException("Couldn't store contact checksum", e)
+        }
+    }
+
+    @Throws(ContactsStorageException::class)
+    fun getLastHashCode(): Int {
+        if (Build.VERSION.SDK_INT < Build.VERSION_CODES.N || Build.VERSION.SDK_INT >= Build.VERSION_CODES.O)
+            throw IllegalStateException("getLastHashCode() should not be called on Android != 7")
+
+        try {
+            addressBook.provider!!.query(rawContactSyncURI(), arrayOf(COLUMN_HASHCODE), null, null, null)?.use { c ->
+                if (c.moveToNext() && !c.isNull(0))
+                    return c.getInt(0)
+            }
+            return 0
+        } catch(e: RemoteException) {
+            throw ContactsStorageException("Could't read last hash code", e)
+        }
+    }
+
+
+    fun addToGroup(batch: BatchOperation, groupID: Long) {
+        batch.enqueue(BatchOperation.Operation(
+                ContentProviderOperation.newInsert(dataSyncURI())
+                        .withValue(GroupMembership.MIMETYPE, GroupMembership.CONTENT_ITEM_TYPE)
+                        .withValue(GroupMembership.RAW_CONTACT_ID, id)
+                        .withValue(GroupMembership.GROUP_ROW_ID, groupID)
+        ))
+        groupMemberships.add(groupID)
+
+        batch.enqueue(BatchOperation.Operation(
+                ContentProviderOperation.newInsert(dataSyncURI())
+                        .withValue(CachedGroupMembership.MIMETYPE, CachedGroupMembership.CONTENT_ITEM_TYPE)
+                        .withValue(CachedGroupMembership.RAW_CONTACT_ID, id)
+                        .withValue(CachedGroupMembership.GROUP_ID, groupID)
+                        .withYieldAllowed(true)
+        ))
+        cachedGroupMemberships.add(groupID)
+    }
+
+    fun removeGroupMemberships(batch: BatchOperation) {
+        batch.enqueue(BatchOperation.Operation(
+                ContentProviderOperation.newDelete(dataSyncURI())
+                        .withSelection(
+                                Data.RAW_CONTACT_ID + "=? AND " + Data.MIMETYPE + " IN (?,?)",
+                                arrayOf(id.toString(), GroupMembership.CONTENT_ITEM_TYPE, CachedGroupMembership.CONTENT_ITEM_TYPE)
+                        )
+                        .withYieldAllowed(true)
+        ))
+        groupMemberships.clear()
+        cachedGroupMemberships.clear()
+    }
+
+    /**
+     * Returns the IDs of all groups the contact was member of (cached memberships).
+     * Cached memberships are kept in sync with memberships by DAVdroid and are used to determine
+     * whether a membership has been deleted/added when a raw contact is dirty.
+     * @return set of {@link GroupMembership#GROUP_ROW_ID} (may be empty)
+     * @throws ContactsStorageException   on contact provider errors
+     * @throws FileNotFoundException      if the current contact can't be found
+     */
+    @Throws(FileNotFoundException::class, ContactsStorageException::class)
+    fun getCachedGroupMemberships(): Set<Long> {
+        contact
+        return cachedGroupMemberships
+    }
+
+    /**
+     * Returns the IDs of all groups the contact is member of.
+     * @return set of {@link GroupMembership#GROUP_ROW_ID}s (may be empty)
+     * @throws ContactsStorageException   on contact provider errors
+     * @throws FileNotFoundException      if the current contact can't be found
+     */
+    @Throws(FileNotFoundException::class, ContactsStorageException::class)
+    fun getGroupMemberships(): Set<Long> {
+        contact
+        return groupMemberships
+    }
+
+
+    // factory
+
+    object Factory: AndroidContactFactory<LocalContact> {
+
+        override fun newInstance(addressBook: AndroidAddressBook<LocalContact, *>, id: Long, fileName: String?, eTag: String?) =
+                LocalContact(addressBook, id, fileName, eTag)
+
+        override fun newInstance(addressBook: AndroidAddressBook<LocalContact, *>, contact: Contact, fileName: String?, eTag: String?) =
+                LocalContact(addressBook, contact, fileName, eTag)
+
+    }
+
+}

app/src/main/java/at/bitfire/davdroid/resource/LocalEvent.java

@@ -1,146 +0,0 @@
-/*
- * Copyright © 2013 – 2015 Ricki Hirner (bitfire web engineering).
- * All rights reserved. This program and the accompanying materials
- * are made available under the terms of the GNU Public License v3.0
- * which accompanies this distribution, and is available at
- * http://www.gnu.org/licenses/gpl.html
- */
-
-package at.bitfire.davdroid.resource;
-
-import android.annotation.TargetApi;
-import android.content.ContentProviderOperation;
-import android.content.ContentValues;
-import android.os.Build;
-import android.os.RemoteException;
-import android.provider.CalendarContract;
-import android.provider.CalendarContract.Events;
-import android.support.annotation.NonNull;
-
-import net.fortuna.ical4j.model.property.ProdId;
-
-import at.bitfire.davdroid.BuildConfig;
-import at.bitfire.ical4android.AndroidCalendar;
-import at.bitfire.ical4android.AndroidEvent;
-import at.bitfire.ical4android.AndroidEventFactory;
-import at.bitfire.ical4android.CalendarStorageException;
-import at.bitfire.ical4android.Event;
-import lombok.Getter;
-import lombok.Setter;
-
-@TargetApi(17)
-public class LocalEvent extends AndroidEvent implements LocalResource {
-    static {
-        Event.prodId = new ProdId("+//IDN bitfire.at//DAVdroid/" + BuildConfig.VERSION_NAME + " ical4android ical4j/2.x");
-    }
-
-    static final String COLUMN_ETAG = CalendarContract.Events.SYNC_DATA1,
-                        COLUMN_UID = Build.VERSION.SDK_INT >= 17 ? Events.UID_2445 : Events.SYNC_DATA2,
-                        COLUMN_SEQUENCE = CalendarContract.Events.SYNC_DATA3;
-
-    @Getter protected String fileName;
-    @Getter @Setter protected String eTag;
-
-    public LocalEvent(@NonNull AndroidCalendar calendar, Event event, String fileName, String eTag) {
-        super(calendar, event);
-        this.fileName = fileName;
-        this.eTag = eTag;
-    }
-
-    protected LocalEvent(@NonNull AndroidCalendar calendar, long id, ContentValues baseInfo) {
-        super(calendar, id, baseInfo);
-        if (baseInfo != null) {
-            fileName = baseInfo.getAsString(Events._SYNC_ID);
-            eTag = baseInfo.getAsString(COLUMN_ETAG);
-        }
-    }
-
-
-    /* process LocalEvent-specific fields */
-
-    @Override
-    protected void populateEvent(ContentValues values) {
-        super.populateEvent(values);
-        fileName = values.getAsString(Events._SYNC_ID);
-        eTag = values.getAsString(COLUMN_ETAG);
-        event.uid = values.getAsString(COLUMN_UID);
-
-        event.sequence = values.getAsInteger(COLUMN_SEQUENCE);
-    }
-
-    @Override
-    protected void buildEvent(Event recurrence, ContentProviderOperation.Builder builder) {
-        super.buildEvent(recurrence, builder);
-
-        boolean buildException = recurrence != null;
-        Event eventToBuild = buildException ? recurrence : event;
-
-        builder .withValue(COLUMN_UID, event.uid)
-                .withValue(COLUMN_SEQUENCE, eventToBuild.sequence)
-                .withValue(CalendarContract.Events.DIRTY, 0)
-                .withValue(CalendarContract.Events.DELETED, 0);
-
-        if (buildException)
-            builder.withValue(Events.ORIGINAL_SYNC_ID, fileName);
-        else
-            builder .withValue(Events._SYNC_ID, fileName)
-                    .withValue(COLUMN_ETAG, eTag);
-    }
-
-
-    /* custom queries */
-
-    public void updateFileNameAndUID(String uid) throws CalendarStorageException {
-        try {
-            String newFileName = uid + ".ics";
-
-            ContentValues values = new ContentValues(2);
-            values.put(Events._SYNC_ID, newFileName);
-            values.put(COLUMN_UID, uid);
-            calendar.provider.update(eventSyncURI(), values, null, null);
-
-            fileName = newFileName;
-            if (event != null)
-                event.uid = uid;
-
-        } catch (RemoteException e) {
-            throw new CalendarStorageException("Couldn't update UID", e);
-        }
-    }
-
-    @Override
-    public void clearDirty(String eTag) throws CalendarStorageException {
-        try {
-            ContentValues values = new ContentValues(2);
-            values.put(CalendarContract.Events.DIRTY, 0);
-            values.put(COLUMN_ETAG, eTag);
-            if (event != null)
-                values.put(COLUMN_SEQUENCE, event.sequence);
-            calendar.provider.update(eventSyncURI(), values, null, null);
-
-            this.eTag = eTag;
-        } catch (RemoteException e) {
-            throw new CalendarStorageException("Couldn't update UID", e);
-        }
-    }
-
-
-    static class Factory implements AndroidEventFactory {
-        static final Factory INSTANCE = new Factory();
-
-        @Override
-        public AndroidEvent newInstance(AndroidCalendar calendar, long id, ContentValues baseInfo) {
-            return new LocalEvent(calendar, id, baseInfo);
-        }
-
-        @Override
-        public AndroidEvent newInstance(AndroidCalendar calendar, Event event) {
-            return new LocalEvent(calendar, event, null, null);
-        }
-
-        @Override
-        public AndroidEvent[] newArray(int size) {
-            return new LocalEvent[size];
-        }
-    }
-}

app/src/main/java/at/bitfire/davdroid/resource/LocalEvent.kt

@@ -0,0 +1,141 @@
+/*
+ * Copyright © Ricki Hirner (bitfire web engineering).
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the GNU Public License v3.0
+ * which accompanies this distribution, and is available at
+ * http://www.gnu.org/licenses/gpl.html
+ */
+
+package at.bitfire.davdroid.resource
+
+import android.content.ContentProviderOperation
+import android.content.ContentValues
+import android.provider.CalendarContract
+import android.provider.CalendarContract.Events
+import at.bitfire.davdroid.BuildConfig
+import at.bitfire.ical4android.*
+import net.fortuna.ical4j.model.property.ProdId
+import java.io.FileNotFoundException
+import java.util.*
+
+class LocalEvent: AndroidEvent, LocalResource {
+
+    companion object {
+        init {
+            iCalendar.prodId = ProdId("+//IDN bitfire.at//DAVdroid/" + BuildConfig.VERSION_NAME + " ical4j/2.x")
+        }
+
+        val COLUMN_ETAG = CalendarContract.Events.SYNC_DATA1
+        val COLUMN_SEQUENCE = CalendarContract.Events.SYNC_DATA3
+    }
+
+    override var fileName: String? = null
+    override var eTag: String? = null
+
+    var weAreOrganizer = true
+
+
+    constructor(calendar: AndroidCalendar<*>, event: Event, fileName: String?, eTag: String?): super(calendar, event) {
+        this.fileName = fileName
+        this.eTag = eTag
+    }
+
+    private constructor(calendar: AndroidCalendar<*>, id: Long, baseInfo: ContentValues?): super(calendar, id, baseInfo) {
+        baseInfo?.let {
+            fileName = it.getAsString(Events._SYNC_ID)
+            eTag = it.getAsString(COLUMN_ETAG)
+        }
+    }
+
+
+    /* process LocalEvent-specific fields */
+
+    @Throws(FileNotFoundException::class, CalendarStorageException::class)
+    override fun populateEvent(row: ContentValues) {
+        super.populateEvent(row)
+        val event = requireNotNull(event)
+
+        fileName = row.getAsString(Events._SYNC_ID)
+        eTag = row.getAsString(COLUMN_ETAG)
+        event.uid = row.getAsString(Events.UID_2445)
+
+        event.sequence = row.getAsInteger(COLUMN_SEQUENCE)
+        val isOrganizer = row.getAsInteger(Events.IS_ORGANIZER)
+        weAreOrganizer = isOrganizer != null && isOrganizer != 0
+    }
+
+    @Throws(FileNotFoundException::class, CalendarStorageException::class)
+    override fun buildEvent(recurrence: Event?, builder: ContentProviderOperation.Builder) {
+        super.buildEvent(recurrence, builder)
+        val event = requireNotNull(event)
+
+        val buildException = recurrence != null
+        val eventToBuild = recurrence ?: event
+
+        builder .withValue(Events.UID_2445, event.uid)
+                .withValue(COLUMN_SEQUENCE, eventToBuild.sequence)
+                .withValue(CalendarContract.Events.DIRTY, 0)
+                .withValue(CalendarContract.Events.DELETED, 0)
+
+        if (buildException)
+            builder .withValue(Events.ORIGINAL_SYNC_ID, fileName)
+        else
+            builder .withValue(Events._SYNC_ID, fileName)
+                    .withValue(COLUMN_ETAG, eTag)
+    }
+
+
+    /* custom queries */
+
+    @Throws(CalendarStorageException::class)
+    override fun prepareForUpload() {
+        try {
+            var uid: String? = null
+            calendar.provider.query(eventSyncURI(), arrayOf(Events.UID_2445), null, null, null)?.use { cursor ->
+                if (cursor.moveToNext())
+                    uid = cursor.getString(0)
+            }
+            if (uid == null)
+                uid = UUID.randomUUID().toString()
+
+            val newFileName = "$uid.ics"
+
+            val values = ContentValues(2)
+            values.put(Events._SYNC_ID, newFileName)
+            values.put(Events.UID_2445, uid)
+            calendar.provider.update(eventSyncURI(), values, null, null)
+
+            fileName = newFileName
+            event!!.uid = uid
+
+        } catch(e: Exception) {
+            throw CalendarStorageException("Couldn't update UID", e)
+        }
+    }
+
+    @Throws(CalendarStorageException::class)
+    override fun clearDirty(eTag: String?) {
+        try {
+            val values = ContentValues(2)
+            values.put(CalendarContract.Events.DIRTY, 0)
+            values.put(COLUMN_ETAG, eTag)
+            values.put(COLUMN_SEQUENCE, event!!.sequence)
+            calendar.provider.update(eventSyncURI(), values, null, null)
+
+            this.eTag = eTag
+        } catch (e: Exception) {
+            throw CalendarStorageException("Couldn't update UID", e)
+        }
+    }
+
+
+    object Factory: AndroidEventFactory<LocalEvent> {
+
+        override fun newInstance(calendar: AndroidCalendar<*>, id: Long, baseInfo: ContentValues?) =
+                LocalEvent(calendar, id, baseInfo)
+
+        override fun newInstance(calendar: AndroidCalendar<*>, event: Event) =
+                LocalEvent(calendar, event, null, null)
+
+    }
+}

app/src/main/java/at/bitfire/davdroid/resource/LocalGroup.java

@@ -1,35 +0,0 @@
-/*
- * Copyright © 2013 – 2015 Ricki Hirner (bitfire web engineering).
- * All rights reserved. This program and the accompanying materials
- * are made available under the terms of the GNU Public License v3.0
- * which accompanies this distribution, and is available at
- * http://www.gnu.org/licenses/gpl.html
- */
-
-package at.bitfire.davdroid.resource;
-
-import android.content.ContentValues;
-import android.provider.ContactsContract;
-
-import at.bitfire.vcard4android.AndroidAddressBook;
-import at.bitfire.vcard4android.AndroidGroup;
-import at.bitfire.vcard4android.Contact;
-import at.bitfire.vcard4android.ContactsStorageException;
-
-public class LocalGroup extends AndroidGroup {
-
-    public LocalGroup(AndroidAddressBook addressBook, long id) {
-        super(addressBook, id);
-    }
-
-    public LocalGroup(AndroidAddressBook addressBook, Contact contact) {
-        super(addressBook, contact);
-    }
-
-    public void clearDirty() throws ContactsStorageException {
-        ContentValues values = new ContentValues(1);
-        values.put(ContactsContract.Groups.DIRTY, 0);
-        update(values);
-    }
-
-}

app/src/main/java/at/bitfire/davdroid/resource/LocalGroup.kt

@@ -0,0 +1,255 @@
+/*
+ * Copyright © Ricki Hirner (bitfire web engineering).
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the GNU Public License v3.0
+ * which accompanies this distribution, and is available at
+ * http://www.gnu.org/licenses/gpl.html
+ */
+
+package at.bitfire.davdroid.resource
+
+import android.content.ContentProviderOperation
+import android.content.ContentUris
+import android.content.ContentValues
+import android.os.Build
+import android.os.Parcel
+import android.os.RemoteException
+import android.provider.ContactsContract
+import android.provider.ContactsContract.CommonDataKinds.GroupMembership
+import android.provider.ContactsContract.Groups
+import android.provider.ContactsContract.RawContacts
+import android.provider.ContactsContract.RawContacts.Data
+import at.bitfire.dav4android.Constants
+import at.bitfire.vcard4android.*
+import java.io.FileNotFoundException
+import java.util.*
+import java.util.logging.Level
+
+class LocalGroup: AndroidGroup, LocalResource {
+
+    companion object {
+
+        /** marshaled list of member UIDs, as sent by server */
+        val COLUMN_PENDING_MEMBERS = Groups.SYNC3
+
+        /**
+         * Processes all groups with non-null {@link #COLUMN_PENDING_MEMBERS}: the pending memberships
+         * are (if possible) applied, keeping cached memberships in sync.
+         * @param addressBook    address book to take groups from
+         * @throws ContactsStorageException on contact provider errors
+         */
+        @JvmStatic
+        @Throws(ContactsStorageException::class)
+        fun applyPendingMemberships(addressBook: LocalAddressBook) {
+            try {
+                addressBook.provider!!.query(
+                        addressBook.syncAdapterURI(Groups.CONTENT_URI),
+                        arrayOf(Groups._ID, COLUMN_PENDING_MEMBERS),
+                        "$COLUMN_PENDING_MEMBERS IS NOT NULL", null,
+                        null
+                )?.use { cursor ->
+                    val batch = BatchOperation(addressBook.provider)
+                    while (cursor.moveToNext()) {
+                        val id = cursor.getLong(0)
+                        Constants.log.fine("Assigning members to group $id")
+
+                        // required for workaround for Android 7 which sets DIRTY flag when only meta-data is changed
+                        val changeContactIDs = HashSet<Long>()
+
+                        // delete all memberships and cached memberships for this group
+                        for (contact in addressBook.getByGroupMembership(id)) {
+                            contact.removeGroupMemberships(batch)
+                            changeContactIDs.add(contact.id!!)
+                        }
+
+                        // extract list of member UIDs
+                        val members = LinkedList<String>()
+                        val raw = cursor.getBlob(1)
+                        val parcel = Parcel.obtain()
+                        try {
+                            parcel.unmarshall(raw, 0, raw.size)
+                            parcel.setDataPosition(0)
+                            parcel.readStringList(members)
+                        } finally {
+                            parcel.recycle()
+                        }
+
+                        // insert memberships
+                        for (uid in members) {
+                            Constants.log.fine("Assigning member: $uid")
+                            try {
+                                val member = addressBook.findContactByUID(uid)
+                                member.addToGroup(batch, id)
+                                changeContactIDs.add(member.id!!)
+                            } catch(e: FileNotFoundException) {
+                                Constants.log.log(Level.WARNING, "Group member not found: $uid", e)
+                            }
+                        }
+
+                        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.N && Build.VERSION.SDK_INT < Build.VERSION_CODES.O)
+                            // workaround for Android 7 which sets DIRTY flag when only meta-data is changed
+                            changeContactIDs
+                                    .map { LocalContact(addressBook, it, null, null) }
+                                    .forEach { it.updateHashCode(batch) }
+
+                        // remove pending memberships
+                        batch.enqueue(BatchOperation.Operation(
+                                ContentProviderOperation.newUpdate(addressBook.syncAdapterURI(ContentUris.withAppendedId(Groups.CONTENT_URI, id)))
+                                        .withValue(COLUMN_PENDING_MEMBERS, null)
+                                        .withYieldAllowed(true)
+                                ))
+
+                        batch.commit()
+                    }
+                }
+            } catch(e: RemoteException) {
+                throw ContactsStorageException("Couldn't get pending memberships", e)
+            }
+        }
+
+    }
+
+
+    constructor(addressBook: AndroidAddressBook<out AndroidContact, LocalGroup>, id: Long, fileName: String?, eTag: String?):
+        super(addressBook, id, fileName, eTag)
+
+    constructor(addressBook: AndroidAddressBook<out AndroidContact, LocalGroup>, contact: Contact, fileName: String?, eTag: String?):
+        super(addressBook, contact, fileName, eTag)
+
+
+    @Throws(ContactsStorageException::class)
+    fun resetDeleted() {
+        val uri = ContentUris.withAppendedId(addressBook.syncAdapterURI(ContactsContract.Groups.CONTENT_URI), requireNotNull(id))
+
+        val values = ContentValues(1)
+        values.put(ContactsContract.Groups.DELETED, 0)
+        try {
+            addressBook.provider!!.update(uri, values, null, null)
+        } catch(e: RemoteException) {
+            throw ContactsStorageException("Couldn't clear deleted flag", e)
+        }
+    }
+
+    @Throws(ContactsStorageException::class)
+    override fun clearDirty(eTag: String?) {
+        val id = requireNotNull(id)
+
+        val values = ContentValues(2)
+        values.put(Groups.DIRTY, 0)
+        values.put(COLUMN_ETAG, eTag)
+        this.eTag = eTag
+        update(values)
+
+        // update cached group memberships
+        val batch = BatchOperation(addressBook.provider!!)
+
+        // delete cached group memberships
+        batch.enqueue(BatchOperation.Operation(
+                ContentProviderOperation.newDelete(addressBook.syncAdapterURI(ContactsContract.Data.CONTENT_URI))
+                        .withSelection(
+                                CachedGroupMembership.MIMETYPE + "=? AND " + CachedGroupMembership.GROUP_ID + "=?",
+                                arrayOf(CachedGroupMembership.CONTENT_ITEM_TYPE, id.toString())
+                        )
+        ))
+
+        // insert updated cached group memberships
+        for (member in getMembers())
+            batch.enqueue(BatchOperation.Operation(
+                    ContentProviderOperation.newInsert(addressBook.syncAdapterURI(ContactsContract.Data.CONTENT_URI))
+                            .withValue(CachedGroupMembership.MIMETYPE, CachedGroupMembership.CONTENT_ITEM_TYPE)
+                            .withValue(CachedGroupMembership.RAW_CONTACT_ID, member)
+                            .withValue(CachedGroupMembership.GROUP_ID, id)
+                            .withYieldAllowed(true)
+            ))
+
+        batch.commit()
+    }
+
+    @Throws(ContactsStorageException::class)
+    override fun prepareForUpload() {
+        val uid = UUID.randomUUID().toString()
+        val newFileName = "$uid.vcf"
+
+        val values = ContentValues(2)
+        values.put(COLUMN_FILENAME, newFileName)
+        values.put(COLUMN_UID, uid)
+        update(values)
+
+        fileName = newFileName
+    }
+
+    @Throws(FileNotFoundException::class, ContactsStorageException::class)
+    override fun contentValues(): ContentValues  {
+        val values = super.contentValues()
+
+        val members = Parcel.obtain()
+        try {
+            members.writeStringList(contact!!.members)
+            values.put(COLUMN_PENDING_MEMBERS, members.marshall())
+        } finally {
+            members.recycle()
+        }
+        return values
+    }
+
+
+    /**
+     * Marks all members of the current group as dirty.
+     */
+    @Throws(ContactsStorageException::class)
+    fun markMembersDirty() {
+        val batch = BatchOperation(addressBook.provider!!)
+
+        for (member in getMembers())
+            batch.enqueue(BatchOperation.Operation(
+                    ContentProviderOperation.newUpdate(addressBook.syncAdapterURI(ContentUris.withAppendedId(RawContacts.CONTENT_URI, member)))
+                            .withValue(RawContacts.DIRTY, 1)
+                            .withYieldAllowed(true)
+            ))
+
+        batch.commit()
+    }
+
+
+    // helpers
+
+    /**
+     * Lists all members of this group.
+     * @return list of all members' raw contact IDs
+     * @throws ContactsStorageException on contact provider errorst
+     */
+    @Throws(ContactsStorageException::class)
+    internal fun getMembers(): List<Long> {
+        val id = requireNotNull(id)
+        val members = LinkedList<Long>()
+        try {
+            addressBook.provider!!.query(
+                    addressBook.syncAdapterURI(ContactsContract.Data.CONTENT_URI),
+                    arrayOf(Data.RAW_CONTACT_ID),
+                    "${GroupMembership.MIMETYPE}=? AND ${GroupMembership.GROUP_ROW_ID}=?",
+                    arrayOf(GroupMembership.CONTENT_ITEM_TYPE, id.toString()),
+                    null
+            )?.use { cursor ->
+                while (cursor.moveToNext())
+                    members.add(cursor.getLong(0))
+            }
+        } catch(e: RemoteException) {
+            throw ContactsStorageException("Couldn't list group members", e)
+        }
+        return members
+    }
+
+
+    // factory
+
+    object Factory: AndroidGroupFactory<LocalGroup> {
+
+        override fun newInstance(addressBook: AndroidAddressBook<out AndroidContact, LocalGroup>, id: Long, fileName: String?, eTag: String?) =
+                LocalGroup(addressBook, id, fileName, eTag)
+
+        override fun newInstance(addressBook: AndroidAddressBook<out AndroidContact, LocalGroup>, contact: Contact, fileName: String?, eTag: String?) =
+                LocalGroup(addressBook, contact, fileName, eTag)
+
+    }
+
+}

app/src/main/java/at/bitfire/davdroid/resource/LocalResource.java

@@ -1,26 +0,0 @@
-/*
- * Copyright © 2013 – 2015 Ricki Hirner (bitfire web engineering).
- * All rights reserved. This program and the accompanying materials
- * are made available under the terms of the GNU Public License v3.0
- * which accompanies this distribution, and is available at
- * http://www.gnu.org/licenses/gpl.html
- */
-
-package at.bitfire.davdroid.resource;
-
-import at.bitfire.ical4android.CalendarStorageException;
-import at.bitfire.vcard4android.ContactsStorageException;
-
-public interface LocalResource {
-
-    Long getId();
-
-    String getFileName();
-    String getETag();
-
-    int delete() throws CalendarStorageException, ContactsStorageException;
-
-    void updateFileNameAndUID(String uuid) throws CalendarStorageException, ContactsStorageException;
-    void clearDirty(String eTag) throws CalendarStorageException, ContactsStorageException;
-
-}

app/src/main/java/at/bitfire/davdroid/resource/LocalResource.kt

@@ -0,0 +1,30 @@
+/*
+ * Copyright © Ricki Hirner (bitfire web engineering).
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the GNU Public License v3.0
+ * which accompanies this distribution, and is available at
+ * http://www.gnu.org/licenses/gpl.html
+ */
+
+package at.bitfire.davdroid.resource
+
+import at.bitfire.ical4android.CalendarStorageException
+import at.bitfire.vcard4android.ContactsStorageException
+
+interface LocalResource {
+
+    val id: Long?
+
+    var fileName: String?
+    var eTag: String?
+
+    @Throws(CalendarStorageException::class, ContactsStorageException::class)
+    fun delete(): Int
+
+    @Throws(CalendarStorageException::class, ContactsStorageException::class)
+    fun prepareForUpload()
+
+    @Throws(CalendarStorageException::class, ContactsStorageException::class)
+    fun clearDirty(eTag: String?)
+
+}

app/src/main/java/at/bitfire/davdroid/resource/LocalTask.java

@@ -1,138 +0,0 @@
-/*
- * Copyright © 2013 – 2015 Ricki Hirner (bitfire web engineering).
- * All rights reserved. This program and the accompanying materials
- * are made available under the terms of the GNU Public License v3.0
- * which accompanies this distribution, and is available at
- * http://www.gnu.org/licenses/gpl.html
- */
-
-package at.bitfire.davdroid.resource;
-
-import android.content.ContentProviderOperation;
-import android.content.ContentValues;
-import android.os.RemoteException;
-import android.provider.CalendarContract.Events;
-import android.support.annotation.NonNull;
-
-import net.fortuna.ical4j.model.property.ProdId;
-
-import org.dmfs.provider.tasks.TaskContract.Tasks;
-
-import java.io.FileNotFoundException;
-import java.text.ParseException;
-
-import at.bitfire.davdroid.BuildConfig;
-import at.bitfire.ical4android.AndroidTask;
-import at.bitfire.ical4android.AndroidTaskFactory;
-import at.bitfire.ical4android.AndroidTaskList;
-import at.bitfire.ical4android.CalendarStorageException;
-import at.bitfire.ical4android.Task;
-import lombok.Getter;
-import lombok.Setter;
-
-public class LocalTask extends AndroidTask implements LocalResource {
-    static {
-        Task.prodId = new ProdId("+//IDN bitfire.at//DAVdroid/" + BuildConfig.VERSION_NAME + " ical4android ical4j/2.x");
-    }
-
-    static final String COLUMN_ETAG = Tasks.SYNC1,
-                        COLUMN_UID = Tasks.SYNC2,
-                        COLUMN_SEQUENCE = Tasks.SYNC3;
-
-    @Getter protected String fileName;
-    @Getter @Setter protected String eTag;
-
-    public LocalTask(@NonNull AndroidTaskList taskList, Task task, String fileName, String eTag) {
-        super(taskList, task);
-        this.fileName = fileName;
-        this.eTag = eTag;
-    }
-
-    protected LocalTask(@NonNull AndroidTaskList taskList, long id, ContentValues baseInfo) {
-        super(taskList, id);
-        if (baseInfo != null) {
-            fileName = baseInfo.getAsString(Events._SYNC_ID);
-            eTag = baseInfo.getAsString(COLUMN_ETAG);
-        }
-    }
-
-
-    /* process LocalTask-specific fields */
-
-    @Override
-    protected void populateTask(ContentValues values) throws FileNotFoundException, RemoteException, ParseException {
-        super.populateTask(values);
-
-        fileName = values.getAsString(Events._SYNC_ID);
-        eTag = values.getAsString(COLUMN_ETAG);
-        task.uid = values.getAsString(COLUMN_UID);
-
-        task.sequence = values.getAsInteger(COLUMN_SEQUENCE);
-    }
-
-    @Override
-    protected void buildTask(ContentProviderOperation.Builder builder, boolean update) {
-        super.buildTask(builder, update);
-        builder .withValue(Tasks._SYNC_ID, fileName)
-                .withValue(COLUMN_UID, task.uid)
-                .withValue(COLUMN_SEQUENCE, task.sequence)
-                .withValue(COLUMN_ETAG, eTag);
-    }
-
-
-    /* custom queries */
-
-    public void updateFileNameAndUID(String uid) throws CalendarStorageException {
-        try {
-            String newFileName = uid + ".ics";
-
-            ContentValues values = new ContentValues(2);
-            values.put(Tasks._SYNC_ID, newFileName);
-            values.put(COLUMN_UID, uid);
-            taskList.provider.client.update(taskSyncURI(), values, null, null);
-
-            fileName = newFileName;
-            if (task != null)
-                task.uid = uid;
-
-        } catch (RemoteException e) {
-            throw new CalendarStorageException("Couldn't update UID", e);
-        }
-    }
-
-    @Override
-    public void clearDirty(String eTag) throws CalendarStorageException {
-        try {
-            ContentValues values = new ContentValues(2);
-            values.put(Tasks._DIRTY, 0);
-            values.put(COLUMN_ETAG, eTag);
-            if (task != null)
-                values.put(COLUMN_SEQUENCE, task.sequence);
-            taskList.provider.client.update(taskSyncURI(), values, null, null);
-
-            this.eTag = eTag;
-        } catch (RemoteException e) {
-            throw new CalendarStorageException("Couldn't update _DIRTY/ETag/SEQUENCE", e);
-        }
-    }
-
-
-    static class Factory implements AndroidTaskFactory {
-        static final Factory INSTANCE = new Factory();
-
-        @Override
-        public LocalTask newInstance(AndroidTaskList taskList, long id, ContentValues baseInfo) {
-            return new LocalTask(taskList, id, baseInfo);
-        }
-
-        @Override
-        public LocalTask newInstance(AndroidTaskList taskList, Task task) {
-            return new LocalTask(taskList, task, null, null);
-        }
-
-        @Override
-        public LocalTask[] newArray(int size) {
-            return new LocalTask[size];
-        }
-    }
-}

app/src/main/java/at/bitfire/davdroid/resource/LocalTask.kt

@@ -0,0 +1,114 @@
+/*
+ * Copyright © Ricki Hirner (bitfire web engineering).
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the GNU Public License v3.0
+ * which accompanies this distribution, and is available at
+ * http://www.gnu.org/licenses/gpl.html
+ */
+
+package at.bitfire.davdroid.resource
+
+import android.content.ContentProviderOperation
+import android.content.ContentValues
+import android.provider.CalendarContract.Events
+import at.bitfire.ical4android.*
+import org.dmfs.tasks.contract.TaskContract.Tasks
+import java.io.FileNotFoundException
+import java.text.ParseException
+import java.util.*
+
+class LocalTask: AndroidTask, LocalResource {
+
+    companion object {
+        val COLUMN_ETAG = Tasks.SYNC_VERSION
+        val COLUMN_SEQUENCE = Tasks.SYNC3
+    }
+
+    override var fileName: String? = null
+    override var eTag: String? = null
+
+    constructor(taskList: AndroidTaskList<*>, task: Task, fileName: String?, eTag: String?): super(taskList, task) {
+        this.fileName = fileName
+        this.eTag = eTag
+    }
+
+    private constructor(taskList: AndroidTaskList<*>, id: Long, baseInfo: ContentValues?): super(taskList, id) {
+        baseInfo?.let {
+            fileName = it.getAsString(Events._SYNC_ID)
+            eTag = it.getAsString(COLUMN_ETAG)
+        }
+    }
+
+
+    /* process LocalTask-specific fields */
+
+    @Throws(ParseException::class)
+    override fun populateTask(values: ContentValues) {
+        super.populateTask(values)
+
+        fileName = values.getAsString(Events._SYNC_ID)
+        eTag = values.getAsString(COLUMN_ETAG)
+
+        val task = requireNotNull(task)
+        task.sequence = values.getAsInteger(COLUMN_SEQUENCE)
+    }
+
+    @Throws(FileNotFoundException::class, CalendarStorageException::class)
+    override fun buildTask(builder: ContentProviderOperation.Builder, update: Boolean) {
+        super.buildTask(builder, update)
+        val task = requireNotNull(task)
+
+        builder .withValue(Tasks._SYNC_ID, fileName)
+                .withValue(COLUMN_SEQUENCE, task.sequence)
+                .withValue(COLUMN_ETAG, eTag)
+    }
+
+
+    /* custom queries */
+
+    @Throws(CalendarStorageException::class)
+    override fun prepareForUpload() {
+        try {
+            val uid = UUID.randomUUID().toString()
+            val newFileName = uid + ".ics"
+
+            val values = ContentValues(2)
+            values.put(Tasks._SYNC_ID, newFileName)
+            values.put(Tasks._UID, uid)
+            taskList.provider.client.update(taskSyncURI(), values, null, null)
+
+            fileName = newFileName
+
+            task!!.uid = uid
+        } catch (e: Exception) {
+            throw CalendarStorageException("Couldn't update UID", e)
+        }
+    }
+
+    @Throws(CalendarStorageException::class)
+    override fun clearDirty(eTag: String?) {
+        try {
+            val values = ContentValues(2)
+            values.put(Tasks._DIRTY, 0)
+            values.put(COLUMN_ETAG, eTag)
+
+            values.put(COLUMN_SEQUENCE, task!!.sequence)
+            taskList.provider.client.update(taskSyncURI(), values, null, null)
+
+            this.eTag = eTag
+        } catch (e: Exception) {
+            throw CalendarStorageException("Couldn't update _DIRTY/ETag/SEQUENCE", e)
+        }
+    }
+
+
+    object Factory: AndroidTaskFactory<LocalTask> {
+
+        override fun newInstance(calendar: AndroidTaskList<*>, id: Long, baseInfo: ContentValues?) =
+                LocalTask(calendar, id, baseInfo)
+
+        override fun newInstance(calendar: AndroidTaskList<*>, task: Task) =
+                LocalTask(calendar, task, null, null)
+
+    }
+}

app/src/main/java/at/bitfire/davdroid/resource/LocalTaskList.java

@@ -1,157 +0,0 @@
-/*
- * Copyright © 2013 – 2015 Ricki Hirner (bitfire web engineering).
- * All rights reserved. This program and the accompanying materials
- * are made available under the terms of the GNU Public License v3.0
- * which accompanies this distribution, and is available at
- * http://www.gnu.org/licenses/gpl.html
- */
-
-package at.bitfire.davdroid.resource;
-
-import android.accounts.Account;
-import android.content.ContentResolver;
-import android.content.ContentValues;
-import android.database.Cursor;
-import android.net.Uri;
-import android.os.RemoteException;
-import android.support.annotation.NonNull;
-
-import org.dmfs.provider.tasks.TaskContract.TaskLists;
-import org.dmfs.provider.tasks.TaskContract.Tasks;
-
-import java.io.FileNotFoundException;
-
-import at.bitfire.davdroid.model.CollectionInfo;
-import at.bitfire.ical4android.AndroidTaskList;
-import at.bitfire.ical4android.AndroidTaskListFactory;
-import at.bitfire.ical4android.CalendarStorageException;
-import at.bitfire.ical4android.TaskProvider;
-import lombok.Cleanup;
-
-public class LocalTaskList extends AndroidTaskList implements LocalCollection {
-
-    public static final int defaultColor = 0xFFC3EA6E;     // "DAVdroid green"
-
-    public static final String COLUMN_CTAG = TaskLists.SYNC_VERSION;
-
-    static String[] BASE_INFO_COLUMNS = new String[] {
-            Tasks._ID,
-            Tasks._SYNC_ID,
-            LocalTask.COLUMN_ETAG
-    };
-
-    // can be cached, because after installing OpenTasks, you have to re-install DAVdroid anyway
-    private static Boolean tasksProviderAvailable;
-
-
-    @Override
-    protected String[] taskBaseInfoColumns() {
-        return BASE_INFO_COLUMNS;
-    }
-
-
-    protected LocalTaskList(Account account, TaskProvider provider, long id) {
-        super(account, provider, LocalTask.Factory.INSTANCE, id);
-    }
-
-    public static Uri create(Account account, TaskProvider provider, CollectionInfo info) throws CalendarStorageException {
-        ContentValues values = valuesFromCollectionInfo(info);
-        values.put(TaskLists.OWNER, account.name);
-        return create(account, provider, values);
-    }
-
-    public void update(CollectionInfo info) throws CalendarStorageException {
-        update(valuesFromCollectionInfo(info));
-    }
-
-    private static ContentValues valuesFromCollectionInfo(CollectionInfo info) {
-        ContentValues values = new ContentValues();
-        values.put(TaskLists._SYNC_ID, info.url);
-        values.put(TaskLists.LIST_NAME, info.displayName);
-        values.put(TaskLists.LIST_COLOR, info.color != null ? info.color : defaultColor);
-        values.put(TaskLists.SYNC_ENABLED, 1);
-        values.put(TaskLists.VISIBLE, 1);
-        return values;
-    }
-
-
-    @Override
-    public LocalTask[] getAll() throws CalendarStorageException {
-        return (LocalTask[])queryTasks(null, null);
-    }
-
-    @Override
-    public LocalTask[] getDeleted() throws CalendarStorageException {
-        return (LocalTask[])queryTasks(Tasks._DELETED + "!=0", null);
-    }
-
-    @Override
-    public LocalTask[] getWithoutFileName() throws CalendarStorageException {
-        return (LocalTask[])queryTasks(Tasks._SYNC_ID + " IS NULL", null);
-    }
-
-    @Override
-    public LocalResource[] getDirty() throws CalendarStorageException, FileNotFoundException {
-        LocalTask[] tasks = (LocalTask[])queryTasks(Tasks._DIRTY + "!=0", null);
-        if (tasks != null)
-        for (LocalTask task : tasks) {
-            if (task.getTask().sequence == null)    // sequence has not been assigned yet (i.e. this task was just locally created)
-                task.getTask().sequence = 0;
-            else
-                task.getTask().sequence++;
-        }
-        return tasks;
-    }
-
-
-    @Override
-    @SuppressWarnings("Recycle")
-    public String getCTag() throws CalendarStorageException {
-        try {
-            @Cleanup Cursor cursor = provider.client.query(taskListSyncUri(), new String[] { COLUMN_CTAG }, null, null, null);
-            if (cursor != null && cursor.moveToNext())
-                return cursor.getString(0);
-        } catch (RemoteException e) {
-            throw new CalendarStorageException("Couldn't read local (last known) CTag", e);
-        }
-        return null;
-    }
-
-    @Override
-    public void setCTag(String cTag) throws CalendarStorageException {
-        try {
-            ContentValues values = new ContentValues(1);
-            values.put(COLUMN_CTAG, cTag);
-            provider.client.update(taskListSyncUri(), values, null, null);
-        } catch (RemoteException e) {
-            throw new CalendarStorageException("Couldn't write local (last known) CTag", e);
-        }
-    }
-
-
-    // helpers
-
-    public static boolean tasksProviderAvailable(@NonNull ContentResolver resolver) {
-        if (tasksProviderAvailable != null)
-            return tasksProviderAvailable;
-        else {
-            TaskProvider provider = TaskProvider.acquire(resolver, TaskProvider.ProviderName.OpenTasks);
-            return tasksProviderAvailable = (provider != null);
-        }
-    }
-
-
-    public static class Factory implements AndroidTaskListFactory {
-        public static final Factory INSTANCE = new Factory();
-
-        @Override
-        public AndroidTaskList newInstance(Account account, TaskProvider provider, long id) {
-            return new LocalTaskList(account, provider, id);
-        }
-
-        @Override
-        public AndroidTaskList[] newArray(int size) {
-            return new LocalTaskList[size];
-        }
-    }
-}

app/src/main/java/at/bitfire/davdroid/resource/LocalTaskList.kt

@@ -0,0 +1,164 @@
+/*
+ * Copyright © Ricki Hirner (bitfire web engineering).
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the GNU Public License v3.0
+ * which accompanies this distribution, and is available at
+ * http://www.gnu.org/licenses/gpl.html
+ */
+
+package at.bitfire.davdroid.resource
+
+import android.accounts.Account
+import android.content.ContentProviderClient
+import android.content.ContentResolver
+import android.content.ContentValues
+import android.content.Context
+import android.net.Uri
+import android.os.Build
+import at.bitfire.davdroid.DavUtils
+import at.bitfire.davdroid.model.CollectionInfo
+import at.bitfire.ical4android.AndroidTaskList
+import at.bitfire.ical4android.AndroidTaskListFactory
+import at.bitfire.ical4android.CalendarStorageException
+import at.bitfire.ical4android.TaskProvider
+import org.dmfs.tasks.contract.TaskContract.TaskLists
+import org.dmfs.tasks.contract.TaskContract.Tasks
+import java.io.FileNotFoundException
+
+class LocalTaskList private constructor(
+        account: Account,
+        provider: TaskProvider,
+        id: Long
+): AndroidTaskList<LocalTask>(account, provider, LocalTask.Factory, id), LocalCollection<LocalTask> {
+
+    companion object {
+
+        val defaultColor = 0xFFC3EA6E.toInt()     // "DAVdroid green"
+
+        val COLUMN_CTAG = TaskLists.SYNC_VERSION
+
+        val BASE_INFO_COLUMNS = arrayOf(
+            Tasks._ID,
+            Tasks._SYNC_ID,
+            LocalTask.COLUMN_ETAG
+        )
+
+        @JvmStatic
+        fun tasksProviderAvailable(context: Context): Boolean {
+            if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M)
+                return context.packageManager.resolveContentProvider(TaskProvider.ProviderName.OpenTasks.authority, 0) != null
+            else {
+                val provider = TaskProvider.acquire(context, TaskProvider.ProviderName.OpenTasks)
+                provider?.use { return true }
+                return false
+            }
+        }
+
+        @JvmStatic
+        @Throws(CalendarStorageException::class)
+        fun create(account: Account, provider: TaskProvider, info: CollectionInfo): Uri {
+            val values = valuesFromCollectionInfo(info, true)
+            values.put(TaskLists.OWNER, account.name)
+            values.put(TaskLists.SYNC_ENABLED, 1)
+            values.put(TaskLists.VISIBLE, 1)
+            return create(account, provider, values)
+        }
+
+        @JvmStatic
+        @Throws(Exception::class)
+        fun onRenameAccount(resolver: ContentResolver, oldName: String, newName: String) {
+            var client: ContentProviderClient? = null
+            try {
+                client = resolver.acquireContentProviderClient(TaskProvider.ProviderName.OpenTasks.authority)
+                client?.use {
+                    val values = ContentValues(1)
+                    values.put(Tasks.ACCOUNT_NAME, newName)
+                    it.update(Tasks.getContentUri(TaskProvider.ProviderName.OpenTasks.authority), values, "${Tasks.ACCOUNT_NAME}=?", arrayOf(oldName))
+                }
+            } finally {
+                if (Build.VERSION.SDK_INT >= 24)
+                    client?.close()
+                else
+                    client?.release()
+            }
+        }
+
+        private fun valuesFromCollectionInfo(info: CollectionInfo, withColor: Boolean): ContentValues {
+            val values = ContentValues(3)
+            values.put(TaskLists._SYNC_ID, info.url)
+            values.put(TaskLists.LIST_NAME, if (info.displayName.isNullOrBlank()) DavUtils.lastSegmentOfUrl(info.url) else info.displayName)
+
+            if (withColor)
+                values.put(TaskLists.LIST_COLOR, info.color ?: defaultColor)
+
+            return values
+        }
+
+    }
+
+
+    override fun taskBaseInfoColumns() = BASE_INFO_COLUMNS
+
+
+    @Throws(CalendarStorageException::class)
+    fun update(info: CollectionInfo, updateColor: Boolean) {
+        update(valuesFromCollectionInfo(info, updateColor))
+    }
+
+
+    @Throws(CalendarStorageException::class)
+    override fun getAll() = queryTasks(null, null)
+
+    @Throws(CalendarStorageException::class)
+    override fun getDeleted() = queryTasks("${Tasks._DELETED}!=0", null)
+
+    @Throws(CalendarStorageException::class)
+    override fun getWithoutFileName() = queryTasks("${Tasks._SYNC_ID} IS NULL", null)
+
+    @Throws(FileNotFoundException::class, CalendarStorageException::class)
+    override fun getDirty(): List<LocalTask> {
+        val tasks = queryTasks("${Tasks._DIRTY}!=0", null)
+        for (localTask in tasks) {
+            val task = requireNotNull(localTask.task)
+            val sequence = task.sequence
+            if (sequence == null)    // sequence has not been assigned yet (i.e. this task was just locally created)
+                task.sequence = 0
+            else
+                task.sequence = sequence + 1
+        }
+        return tasks
+    }
+
+
+    @Throws(CalendarStorageException::class)
+    override fun getCTag(): String? =
+        try {
+            provider.client.query(taskListSyncUri(), arrayOf(COLUMN_CTAG), null, null, null)?.use { cursor ->
+                if (cursor.moveToNext())
+                    return cursor.getString(0)
+            }
+            null
+        } catch(e: Exception) {
+            throw CalendarStorageException("Couldn't read local (last known) CTag", e)
+        }
+
+    @Throws(CalendarStorageException::class)
+    override fun setCTag(cTag: String?) {
+        try {
+            val values = ContentValues(1)
+            values.put(COLUMN_CTAG, cTag)
+            provider.client.update(taskListSyncUri(), values, null, null)
+        } catch (e: Exception) {
+            throw CalendarStorageException("Couldn't write local (last known) CTag", e)
+        }
+    }
+
+
+    object Factory: AndroidTaskListFactory<LocalTaskList> {
+
+        override fun newInstance(account: Account, provider: TaskProvider, id: Long) =
+                LocalTaskList(account, provider, id)
+
+    }
+
+}

app/src/main/java/at/bitfire/davdroid/settings/DefaultsProvider.kt

@@ -0,0 +1,74 @@
+/*
+ * Copyright © Ricki Hirner (bitfire web engineering).
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the GNU Public License v3.0
+ * which accompanies this distribution, and is available at
+ * http://www.gnu.org/licenses/gpl.html
+ */
+
+package at.bitfire.davdroid.settings
+
+import at.bitfire.davdroid.App
+
+open class DefaultsProvider(
+        private val allowOverride: Boolean = true
+): Provider {
+
+    open val booleanDefaults = mapOf(
+            Pair(App.DISTRUST_SYSTEM_CERTIFICATES, false),
+            Pair(App.OVERRIDE_PROXY, false)
+    )
+
+    open val intDefaults = mapOf(
+            Pair(App.OVERRIDE_PROXY_PORT, App.OVERRIDE_PROXY_PORT_DEFAULT)
+    )
+
+    open val longDefaults = mapOf<String, Long>()
+
+    open val stringDefaults = mapOf(
+            Pair(App.OVERRIDE_PROXY_HOST, App.OVERRIDE_PROXY_HOST_DEFAULT)
+    )
+
+
+    override fun close() {
+    }
+
+    override fun forceReload() {
+    }
+
+
+    private fun hasKey(key: String) =
+            booleanDefaults.containsKey(key) ||
+            intDefaults.containsKey(key) ||
+            longDefaults.containsKey(key) ||
+            stringDefaults.containsKey(key)
+
+    override fun has(key: String): Pair<Boolean, Boolean> {
+        val has = hasKey(key)
+        return Pair(has, allowOverride || !has)
+    }
+
+
+    override fun getBoolean(key: String) =
+            Pair(booleanDefaults[key], allowOverride || !booleanDefaults.containsKey(key))
+
+    override fun getInt(key: String) =
+            Pair(intDefaults[key], allowOverride || !intDefaults.containsKey(key))
+
+    override fun getLong(key: String) =
+            Pair(longDefaults[key], allowOverride || !longDefaults.containsKey(key))
+
+    override fun getString(key: String) =
+            Pair(stringDefaults[key], allowOverride || !stringDefaults.containsKey(key))
+
+
+    override fun isWritable(key: String) = Pair(false, allowOverride || !hasKey(key))
+
+    override fun putBoolean(key: String, value: Boolean?) = false
+    override fun putInt(key: String, value: Int?) = false
+    override fun putLong(key: String, value: Long?) = false
+    override fun putString(key: String, value: String?) = false
+
+    override fun remove(key: String) = false
+
+}

app/src/main/java/at/bitfire/davdroid/settings/Provider.kt

@@ -0,0 +1,38 @@
+/*
+ * Copyright © Ricki Hirner (bitfire web engineering).
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the GNU Public License v3.0
+ * which accompanies this distribution, and is available at
+ * http://www.gnu.org/licenses/gpl.html
+ */
+
+package at.bitfire.davdroid.settings
+
+import java.io.Closeable
+
+interface Provider: Closeable {
+
+    fun forceReload()
+
+    fun has(key: String): Pair<Boolean, Boolean>
+
+    fun getBoolean(key: String): Pair<Boolean?, Boolean>
+    fun getInt(key: String): Pair<Int?, Boolean>
+    fun getLong(key: String): Pair<Long?, Boolean>
+    fun getString(key: String): Pair<String?, Boolean>
+
+    fun isWritable(key: String): Pair<Boolean, Boolean>
+
+    fun putBoolean(key: String, value: Boolean?): Boolean
+    fun putInt(key: String, value: Int?): Boolean
+    fun putLong(key: String, value: Long?): Boolean
+    fun putString(key: String, value: String?): Boolean
+
+    fun remove(key: String): Boolean
+
+
+    interface Observer {
+        fun onReload()
+    }
+
+}

app/src/main/java/at/bitfire/davdroid/settings/Settings.kt

@@ -0,0 +1,276 @@
+/*
+ * Copyright © Ricki Hirner (bitfire web engineering).
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the GNU Public License v3.0
+ * which accompanies this distribution, and is available at
+ * http://www.gnu.org/licenses/gpl.html
+ */
+
+package at.bitfire.davdroid.settings
+
+import android.annotation.TargetApi
+import android.app.Service
+import android.content.ComponentName
+import android.content.Context
+import android.content.Intent
+import android.content.ServiceConnection
+import android.os.Build
+import android.os.Handler
+import android.os.IBinder
+import android.os.Looper
+import at.bitfire.davdroid.log.Logger
+import java.io.Closeable
+import java.lang.ref.WeakReference
+import java.util.*
+import java.util.logging.Level
+
+class Settings: Service(), Provider.Observer {
+
+    private val providers = LinkedList<Provider>()
+    private val observers = LinkedList<WeakReference<ISettingsObserver>>()
+
+    @TargetApi(Build.VERSION_CODES.LOLLIPOP)
+    override fun onCreate() {
+        Logger.log.info("Initializing Settings service")
+
+        // always add a defaults provider first
+        providers.add(DefaultsProvider())
+
+        // always add a provider for local preferences
+        providers.add(SharedPreferencesProvider(this))
+    }
+
+    override fun onDestroy() {
+        Logger.log.info("Shutting down Settings service")
+        providers.forEach { it.close() }
+        providers.clear()
+    }
+
+    override fun onTrimMemory(level: Int) {
+        stopSelf()
+    }
+
+
+    fun forceReload() {
+        providers.forEach { it.forceReload() }
+    }
+
+    override fun onReload() {
+        observers.forEach {
+            Handler(Looper.getMainLooper()).post {
+                it.get()?.onSettingsChanged()
+            }
+        }
+    }
+
+
+    private fun has(key: String): Boolean {
+        Logger.log.fine("Looking for setting $key")
+        var result = false
+        for (provider in providers)
+            try {
+                val (value, further) = provider.has(key)
+                Logger.log.finer("${provider::class.java.simpleName}: has $key = $value, continue: $further")
+                if (value) {
+                    result = true
+                    break
+                }
+                if (!further)
+                    break
+            } catch(e: Exception) {
+                Logger.log.log(Level.SEVERE, "Couldn't look up setting in $provider", e)
+            }
+        Logger.log.fine("Looking for setting $key -> $result")
+        return result
+    }
+
+    private fun<T> getValue(key: String, reader: (Provider) -> Pair<T?, Boolean>): T? {
+        Logger.log.fine("Looking up setting $key")
+        var result: T? = null
+        for (provider in providers)
+            try {
+                val (value, further) = reader(provider)
+                Logger.log.finer("${provider::class.java.simpleName}: value = $value, continue: $further")
+                value?.let { result = it }
+                if (!further)
+                    break
+            } catch(e: Exception) {
+                Logger.log.log(Level.SEVERE, "Couldn't read setting from $provider", e)
+            }
+        Logger.log.fine("Looked up setting $key -> $result")
+        return result
+    }
+
+    fun getBoolean(key: String) =
+            getValue(key, { provider -> provider.getBoolean(key) })
+
+    fun getInt(key: String) =
+            getValue(key, { provider -> provider.getInt(key) })
+
+    fun getLong(key: String) =
+            getValue(key, { provider -> provider.getLong(key) })
+
+    fun getString(key: String) =
+            getValue(key, { provider -> provider.getString(key) })
+
+
+    fun isWritable(key: String): Boolean {
+        for (provider in providers) {
+            val (value, further) = provider.isWritable(key)
+            if (value)
+                return true
+            if (!further)
+                return false
+        }
+        return false
+    }
+
+    private fun<T> putValue(key: String, value: T?, writer: (Provider) -> Boolean): Boolean {
+        Logger.log.fine("Trying to write setting $key = $value")
+        for (provider in providers) {
+            val (writable, further) = provider.isWritable(key)
+            Logger.log.finer("${provider::class.java.simpleName}: writable = $writable, continue: $further")
+            if (writable)
+                return try {
+                    writer(provider)
+                } catch (e: Exception) {
+                    Logger.log.log(Level.SEVERE, "Couldn't write setting to $provider", e)
+                    false
+                }
+            if (!further)
+                return false
+        }
+        return false
+    }
+
+    fun putBoolean(key: String, value: Boolean?) =
+            putValue(key, value, { provider -> provider.putBoolean(key, value) })
+
+    fun putInt(key: String, value: Int?) =
+            putValue(key, value, { provider -> provider.putInt(key, value) })
+
+    fun putLong(key: String, value: Long?) =
+            putValue(key, value, { provider -> provider.putLong(key, value) })
+
+    fun putString(key: String, value: String?) =
+            putValue(key, value, { provider -> provider.putString(key, value) })
+
+    fun remove(key: String): Boolean {
+        var deleted = false
+        providers.forEach { deleted = deleted || it.remove(key) }
+        return deleted
+    }
+
+
+    val binder = object: ISettings.Stub() {
+
+        override fun forceReload() =
+               this@Settings.forceReload()
+
+        override fun has(key: String) =
+                this@Settings.has(key)
+
+        override fun getBoolean(key: String, defaultValue: Boolean) =
+                this@Settings.getBoolean(key) ?: defaultValue
+
+        override fun getInt(key: String, defaultValue: Int) =
+                this@Settings.getInt(key) ?: defaultValue
+
+        override fun getLong(key: String, defaultValue: Long) =
+                this@Settings.getLong(key) ?: defaultValue
+
+        override fun getString(key: String, defaultValue: String?) =
+                this@Settings.getString(key) ?: defaultValue
+
+        override fun isWritable(key: String) =
+                this@Settings.isWritable(key)
+
+        override fun remove(key: String) =
+                this@Settings.remove(key)
+
+        override fun putBoolean(key: String, value: Boolean) =
+                this@Settings.putBoolean(key, value)
+
+        override fun putString(key: String, value: String?) =
+                this@Settings.putString(key, value)
+
+        override fun putInt(key: String, value: Int) =
+                this@Settings.putInt(key, value)
+
+        override fun putLong(key: String, value: Long) =
+                this@Settings.putLong(key, value)
+
+        override fun registerObserver(observer: ISettingsObserver) {
+            observers += WeakReference(observer)
+        }
+
+        override fun unregisterObserver(observer: ISettingsObserver) {
+            observers.removeAll { it.get() == observer }
+        }
+
+    }
+
+    override fun onBind(intent: Intent?) = binder
+
+
+    class Stub(
+            delegate: ISettings,
+            private val context: Context,
+            private val serviceConn: ServiceConnection
+    ): ISettings by delegate, Closeable {
+
+        override fun close() {
+            try {
+                context.unbindService(serviceConn)
+            } catch(e: Exception) {
+                Logger.log.log(Level.SEVERE, "Couldn't unbind Settings service", e)
+            }
+        }
+
+    }
+
+    companion object {
+
+        fun getInstance(context: Context): Stub? {
+            if (Looper.getMainLooper().thread == Thread.currentThread())
+                throw IllegalStateException("Must not be called from main thread")
+
+            var service: ISettings? = null
+            val serviceLock = Object()
+            val serviceConn = object: ServiceConnection {
+                override fun onServiceConnected(name: ComponentName, binder: IBinder) {
+                    synchronized(serviceLock) {
+                        service = ISettings.Stub.asInterface(binder)
+                        serviceLock.notify()
+                    }
+                }
+                override fun onServiceDisconnected(name: ComponentName) {
+                    service = null
+                }
+            }
+
+            if (!context.bindService(Intent(context, Settings::class.java), serviceConn, Context.BIND_AUTO_CREATE or Context.BIND_IMPORTANT))
+                return null
+
+            synchronized(serviceLock) {
+                if (service == null)
+                    try {
+                        serviceLock.wait()
+                    } catch(e: InterruptedException) {
+                    }
+
+                if (service == null) {
+                    try {
+                        context.unbindService(serviceConn)
+                    } catch (e: IllegalArgumentException) {
+                    }
+                    return null
+                }
+            }
+
+            return Stub(service!!, context, serviceConn)
+        }
+
+    }
+
+}

app/src/main/java/at/bitfire/davdroid/settings/SharedPreferencesProvider.kt

@@ -0,0 +1,120 @@
+/*
+ * Copyright © Ricki Hirner (bitfire web engineering).
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the GNU Public License v3.0
+ * which accompanies this distribution, and is available at
+ * http://www.gnu.org/licenses/gpl.html
+ */
+
+package at.bitfire.davdroid.settings
+
+import android.content.Context
+import android.content.Context.MODE_PRIVATE
+import android.content.SharedPreferences
+import android.preference.PreferenceManager
+import at.bitfire.davdroid.log.Logger
+import at.bitfire.davdroid.model.ServiceDB
+
+class SharedPreferencesProvider(
+        context: Context
+): Provider {
+
+    companion object {
+        private val META_VERSION = "version"
+        private val CURRENT_VERSION = 0
+    }
+
+    private val preferences = PreferenceManager.getDefaultSharedPreferences(context)
+
+    init {
+        val meta = context.getSharedPreferences("meta", MODE_PRIVATE)
+        val version = meta.getInt(META_VERSION, -1)
+        if (version == -1) {
+            // first call, check whether to migrate from SQLite database (DAVdroid <1.9)
+            firstCall(context)
+            meta.edit().putInt(META_VERSION, CURRENT_VERSION).apply()
+        }
+    }
+
+    override fun close() {
+    }
+
+    override fun forceReload() {
+    }
+
+
+    override fun has(key: String) =
+            Pair(preferences.contains(key), true)
+
+    private fun<T> getValue(key: String, reader: (SharedPreferences) -> T): Pair<T?, Boolean> {
+        if (preferences.contains(key))
+            return Pair(
+                    try { reader(preferences) } catch(e: ClassCastException) { null },
+                    true)
+
+        return Pair(null, true)
+    }
+
+    override fun getBoolean(key: String): Pair<Boolean?, Boolean> =
+            getValue(key, { preferences -> preferences.getBoolean(key, /* will never be used: */ false) })
+
+    override fun getInt(key: String): Pair<Int?, Boolean> =
+            getValue(key, { preferences -> preferences.getInt(key, /* will never be used: */ -1) })
+
+    override fun getLong(key: String): Pair<Long?, Boolean> =
+            getValue(key, { preferences -> preferences.getLong(key, /* will never be used: */ -1) })
+
+    override fun getString(key: String): Pair<String?, Boolean> =
+            getValue(key, { preferences -> preferences.getString(key, /* will never be used: */ null) })
+
+
+    override fun isWritable(key: String) =
+            Pair(true, true)
+
+    private fun<T> putValue(key: String, value: T?, writer: (SharedPreferences.Editor, T) -> Unit): Boolean {
+        if (value == null)
+            return remove(key)
+        else {
+            Logger.log.fine("Writing setting $key = $value")
+            val edit = preferences.edit()
+            writer(edit, value)
+            edit.apply()
+            return true
+        }
+    }
+
+    override fun putBoolean(key: String, value: Boolean?) =
+            putValue(key, value, { editor, v -> editor.putBoolean(key, v) })
+
+    override fun putInt(key: String, value: Int?) =
+            putValue(key, value, { editor, v -> editor.putInt(key, v) })
+
+    override fun putLong(key: String, value: Long?) =
+            putValue(key, value, { editor, v -> editor.putLong(key, v) })
+
+    override fun putString(key: String, value: String?) =
+            putValue(key, value, { editor, v -> editor.putString(key, v) })
+
+    override fun remove(key: String): Boolean {
+        Logger.log.fine("Removing setting $key")
+        preferences.edit()
+                .remove(key)
+                .apply()
+        return true
+    }
+
+
+    private fun firstCall(context: Context) {
+        // remove possible artifacts from DAVdroid <1.9
+        val edit = preferences.edit()
+        edit.remove("override_proxy")
+        edit.remove("proxy_host")
+        edit.remove("proxy_port")
+        edit.remove("log_to_external_storage")
+        edit.apply()
+
+        // open ServiceDB to upgrade it and possibly migrate settings
+        ServiceDB.OpenHelper(context).use { it.readableDatabase }
+    }
+
+}

app/src/main/java/at/bitfire/davdroid/syncadapter/AccountAuthenticatorService.java

@@ -1,88 +0,0 @@
-/*
- * Copyright © 2013 – 2015 Ricki Hirner (bitfire web engineering).
- * All rights reserved. This program and the accompanying materials
- * are made available under the terms of the GNU Public License v3.0
- * which accompanies this distribution, and is available at
- * http://www.gnu.org/licenses/gpl.html
- */
-package at.bitfire.davdroid.syncadapter;
-
-import android.accounts.AbstractAccountAuthenticator;
-import android.accounts.Account;
-import android.accounts.AccountAuthenticatorResponse;
-import android.accounts.AccountManager;
-import android.accounts.NetworkErrorException;
-import android.app.Service;
-import android.content.Context;
-import android.content.Intent;
-import android.os.Bundle;
-import android.os.IBinder;
-
-import at.bitfire.davdroid.ui.setup.LoginActivity;
-
-public class AccountAuthenticatorService extends Service {
-	private static AccountAuthenticator accountAuthenticator;
-
-	private AccountAuthenticator getAuthenticator() {
-		if (accountAuthenticator != null)
-			return accountAuthenticator;
-		return accountAuthenticator = new AccountAuthenticator(this);
-	}
-	
-	@Override
-	public IBinder onBind(Intent intent) {
-		if (intent.getAction().equals(android.accounts.AccountManager.ACTION_AUTHENTICATOR_INTENT))
-			return getAuthenticator().getIBinder(); 
-		return null;
-	}
-	
-	
-	private static class AccountAuthenticator extends AbstractAccountAuthenticator {
-		final Context context;
-		
-		public AccountAuthenticator(Context context) {
-			super(context);
-			this.context = context;
-		}
-
-		@Override
-		public Bundle addAccount(AccountAuthenticatorResponse response, String accountType, String authTokenType,
-				String[] requiredFeatures, Bundle options) throws NetworkErrorException {
-			Intent intent = new Intent(context, LoginActivity.class);
-			intent.putExtra(AccountManager.KEY_ACCOUNT_AUTHENTICATOR_RESPONSE, response);
-			Bundle bundle = new Bundle();
-			bundle.putParcelable(AccountManager.KEY_INTENT, intent);
-			return bundle;
-		}
-
-		@Override
-		public Bundle confirmCredentials(AccountAuthenticatorResponse response, Account account, Bundle options) throws NetworkErrorException {
-			return null;
-		}
-
-		@Override
-		public Bundle editProperties(AccountAuthenticatorResponse response, String accountType) {
-			return null;
-		}
-
-        @Override
-		public Bundle getAuthToken(AccountAuthenticatorResponse response, Account account, String authTokenType, Bundle options) throws NetworkErrorException {
-			return null;
-		}
-
-		@Override
-		public String getAuthTokenLabel(String authTokenType) {
-			return null;
-		}
-
-		@Override
-		public Bundle hasFeatures(AccountAuthenticatorResponse response, Account account, String[] features) throws NetworkErrorException {
-			return null;
-		}
-
-		@Override
-		public Bundle updateCredentials(AccountAuthenticatorResponse response, Account account, String authTokenType, Bundle options) throws NetworkErrorException {
-			return null;
-		}
-	}
-}

app/src/main/java/at/bitfire/davdroid/syncadapter/AccountAuthenticatorService.kt

@@ -0,0 +1,117 @@
+/*
+ * Copyright © Ricki Hirner (bitfire web engineering).
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the GNU Public License v3.0
+ * which accompanies this distribution, and is available at
+ * http://www.gnu.org/licenses/gpl.html
+ */
+package at.bitfire.davdroid.syncadapter
+
+import android.accounts.*
+import android.app.Service
+import android.content.Context
+import android.content.Intent
+import android.database.DatabaseUtils
+import android.os.Bundle
+import at.bitfire.davdroid.R
+import at.bitfire.davdroid.log.Logger
+import at.bitfire.davdroid.model.ServiceDB
+import at.bitfire.davdroid.resource.LocalAddressBook
+import at.bitfire.davdroid.ui.setup.LoginActivity
+import at.bitfire.vcard4android.ContactsStorageException
+import java.util.*
+import java.util.logging.Level
+
+
+/**
+ * Account authenticator for the main DAVdroid account type.
+ *
+ * Gets started when a DAVdroid account is removed, too, so it also watches for account removals
+ * and contains the corresponding cleanup code.
+ */
+class AccountAuthenticatorService: Service(), OnAccountsUpdateListener {
+
+    companion object {
+
+        fun cleanupAccounts(context: Context) {
+            Logger.log.info("Cleaning up orphaned accounts")
+
+            ServiceDB.OpenHelper(context).use { dbHelper ->
+                val db = dbHelper.writableDatabase
+
+                val sqlAccountNames = LinkedList<String>()
+                val accountNames = HashSet<String>()
+                val accountManager = AccountManager.get(context)
+                for (account in accountManager.getAccountsByType(context.getString(R.string.account_type))) {
+                    sqlAccountNames.add(DatabaseUtils.sqlEscapeString(account.name))
+                    accountNames += account.name
+                }
+
+                // delete orphaned address book accounts
+                accountManager.getAccountsByType(context.getString(R.string.account_type_address_book))
+                        .map { LocalAddressBook(context, it, null) }
+                        .forEach {
+                            try {
+                                if (!accountNames.contains(it.getMainAccount().name))
+                                    it.delete()
+                            } catch(e: ContactsStorageException) {
+                                Logger.log.log(Level.SEVERE, "Couldn't get address book main account", e)
+                            }
+                        }
+
+                // delete orphaned services in DB
+                if (sqlAccountNames.isEmpty())
+                    db.delete(ServiceDB.Services._TABLE, null, null)
+                else
+                    db.delete(ServiceDB.Services._TABLE, "${ServiceDB.Services.ACCOUNT_NAME} NOT IN (${sqlAccountNames.joinToString(",")})", null)
+            }
+        }
+
+    }
+
+
+    private lateinit var accountManager: AccountManager
+    private lateinit var accountAuthenticator: AccountAuthenticator
+
+    override fun onCreate() {
+        accountManager = AccountManager.get(this)
+        accountManager.addOnAccountsUpdatedListener(this, null, true)
+
+        accountAuthenticator = AccountAuthenticator(this)
+    }
+
+    override fun onDestroy() {
+        super.onDestroy()
+        accountManager.removeOnAccountsUpdatedListener(this)
+    }
+
+    override fun onBind(intent: Intent?) =
+            accountAuthenticator.iBinder.takeIf { intent?.action == android.accounts.AccountManager.ACTION_AUTHENTICATOR_INTENT }
+
+
+    override fun onAccountsUpdated(accounts: Array<out Account>?) {
+        cleanupAccounts(this)
+    }
+
+
+    private class AccountAuthenticator(
+            val context: Context
+    ): AbstractAccountAuthenticator(context) {
+
+        override fun addAccount(response: AccountAuthenticatorResponse?, accountType: String?, authTokenType: String?, requiredFeatures: Array<String>?, options: Bundle?): Bundle {
+            val intent = Intent(context, LoginActivity::class.java)
+            intent.putExtra(AccountManager.KEY_ACCOUNT_AUTHENTICATOR_RESPONSE, response)
+            val bundle = Bundle(1)
+            bundle.putParcelable(AccountManager.KEY_INTENT, intent)
+            return bundle
+        }
+
+        override fun editProperties(response: AccountAuthenticatorResponse?, accountType: String?)  = null
+        override fun getAuthTokenLabel(p0: String?) = null
+        override fun confirmCredentials(p0: AccountAuthenticatorResponse?, p1: Account?, p2: Bundle?) = null
+        override fun updateCredentials(p0: AccountAuthenticatorResponse?, p1: Account?, p2: String?, p3: Bundle?) = null
+        override fun getAuthToken(p0: AccountAuthenticatorResponse?, p1: Account?, p2: String?, p3: Bundle?) = null
+        override fun hasFeatures(p0: AccountAuthenticatorResponse?, p1: Account?, p2: Array<out String>?) = null
+
+    }
+}

app/src/main/java/at/bitfire/davdroid/syncadapter/AddressBookProvider.kt

@@ -0,0 +1,24 @@
+/*
+ * Copyright © Ricki Hirner (bitfire web engineering).
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the GNU Public License v3.0
+ * which accompanies this distribution, and is available at
+ * http://www.gnu.org/licenses/gpl.html
+ */
+
+package at.bitfire.davdroid.syncadapter
+
+import android.content.ContentProvider
+import android.content.ContentValues
+import android.net.Uri
+
+class AddressBookProvider: ContentProvider() {
+
+    override fun onCreate() = false
+    override fun insert(p0: Uri?, p1: ContentValues?) = null
+    override fun query(p0: Uri?, p1: Array<out String>?, p2: String?, p3: Array<out String>?, p4: String?) = null
+    override fun update(p0: Uri?, p1: ContentValues?, p2: String?, p3: Array<out String>?) = 0
+    override fun delete(p0: Uri?, p1: String?, p2: Array<out String>?) = 0
+    override fun getType(p0: Uri?) = null
+
+}

app/src/main/java/at/bitfire/davdroid/syncadapter/AddressBooksSyncAdapterService.kt

@@ -0,0 +1,135 @@
+/*
+ * Copyright © Ricki Hirner (bitfire web engineering).
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the GNU Public License v3.0
+ * which accompanies this distribution, and is available at
+ * http://www.gnu.org/licenses/gpl.html
+ */
+package at.bitfire.davdroid.syncadapter
+
+import android.accounts.Account
+import android.accounts.AccountManager
+import android.content.*
+import android.database.DatabaseUtils
+import android.os.Bundle
+import android.provider.ContactsContract
+import at.bitfire.davdroid.AccountSettings
+import at.bitfire.davdroid.R
+import at.bitfire.davdroid.log.Logger
+import at.bitfire.davdroid.model.CollectionInfo
+import at.bitfire.davdroid.model.ServiceDB
+import at.bitfire.davdroid.model.ServiceDB.Collections
+import at.bitfire.davdroid.resource.LocalAddressBook
+import at.bitfire.davdroid.settings.ISettings
+import at.bitfire.vcard4android.ContactsStorageException
+import java.util.logging.Level
+
+class AddressBooksSyncAdapterService: SyncAdapterService() {
+
+    override fun syncAdapter() = AddressBooksSyncAdapter(this)
+
+
+	protected class AddressBooksSyncAdapter(
+            context: Context
+    ): SyncAdapter(context) {
+
+        override fun sync(settings: ISettings, account: Account, extras: Bundle, authority: String, addressBooksProvider: ContentProviderClient, syncResult: SyncResult) {
+            val contactsProvider = context.contentResolver.acquireContentProviderClient(ContactsContract.AUTHORITY)
+            if (contactsProvider == null) {
+                Logger.log.severe("Couldn't access contacts provider")
+                syncResult.databaseError = true
+                return
+            }
+
+            try {
+                val accountSettings = AccountSettings(context, settings, account)
+
+                /* don't run sync if
+                   - sync conditions (e.g. "sync only in WiFi") are not met AND
+                   - this is is an automatic sync (i.e. manual syncs are run regardless of sync conditions)
+                 */
+                if (!extras.containsKey(ContentResolver.SYNC_EXTRAS_MANUAL) && !checkSyncConditions(accountSettings))
+                    return
+
+                updateLocalAddressBooks(contactsProvider, account)
+
+                val accountManager = AccountManager.get(context)
+                for (addressBookAccount in accountManager.getAccountsByType(context.getString(R.string.account_type_address_book))) {
+                    Logger.log.log(Level.INFO, "Running sync for address book", addressBookAccount)
+                    val syncExtras = Bundle(extras)
+                    syncExtras.putBoolean(ContentResolver.SYNC_EXTRAS_IGNORE_SETTINGS, true)
+                    syncExtras.putBoolean(ContentResolver.SYNC_EXTRAS_IGNORE_BACKOFF, true)
+                    ContentResolver.requestSync(addressBookAccount, ContactsContract.AUTHORITY, syncExtras)
+                }
+            } catch(e: Exception) {
+                Logger.log.log(Level.SEVERE, "Couldn't sync address books", e)
+            }
+
+            Logger.log.info("Address book sync complete")
+        }
+
+        private fun updateLocalAddressBooks(provider: ContentProviderClient, account: Account) {
+            ServiceDB.OpenHelper(context).use { dbHelper ->
+                val db = dbHelper.readableDatabase
+
+                fun getService() =
+                        db.query(ServiceDB.Services._TABLE, arrayOf(ServiceDB.Services.ID),
+                            "${ServiceDB.Services.ACCOUNT_NAME}=? AND ${ServiceDB.Services.SERVICE}=?",
+                            arrayOf(account.name, ServiceDB.Services.SERVICE_CARDDAV), null, null, null)?.use { c ->
+                            if (c.moveToNext())
+                                c.getLong(0)
+                            else
+                                null
+                        }
+
+                fun remoteAddressBooks(service: Long?): MutableMap<String, CollectionInfo> {
+                    val collections = mutableMapOf<String, CollectionInfo>()
+                    service?.let {
+                        db.query(Collections._TABLE, null,
+                            Collections.SERVICE_ID + "=? AND " + Collections.SYNC, arrayOf(service.toString()), null, null, null)?.use { cursor ->
+                            while (cursor.moveToNext()) {
+                                val values = ContentValues(cursor.columnCount)
+                                DatabaseUtils.cursorRowToContentValues(cursor, values)
+                                val info = CollectionInfo(values)
+                                collections[info.url] = info
+                            }
+                        }
+                    }
+                    return collections
+                }
+
+                // enumerate remote and local address books
+                val service = getService()
+                val remote = remoteAddressBooks(service)
+
+                // delete/update local address books
+                for (addressBook in LocalAddressBook.find(context, provider, account)) {
+                    val url = addressBook.getURL()
+                    val info = remote[url]
+                    if (info == null) {
+                        Logger.log.log(Level.INFO, "Deleting obsolete local address book", url)
+                        addressBook.delete()
+                    } else {
+                        // remote CollectionInfo found for this local collection, update data
+                        try {
+                            Logger.log.log(Level.FINE, "Updating local address book $url", info)
+                            addressBook.update(info)
+                        } catch(e: ContactsStorageException) {
+                            Logger.log.log(Level.WARNING, "Couldn't rename address book account", e)
+                        }
+                        // we already have a local address book for this remote collection, don't take into consideration anymore
+                        remote -= url
+                    }
+                }
+
+                // create new local address books
+                for ((_, info) in remote) {
+                    Logger.log.log(Level.INFO, "Adding local address book", info)
+                    LocalAddressBook.create(context, provider, account, info)
+                }
+            }
+        }
+
+    }
+
+}

app/src/main/java/at/bitfire/davdroid/syncadapter/CalendarSyncManager.java

@@ -1,219 +0,0 @@
-/*
- * Copyright © 2013 – 2015 Ricki Hirner (bitfire web engineering).
- * All rights reserved. This program and the accompanying materials
- * are made available under the terms of the GNU Public License v3.0
- * which accompanies this distribution, and is available at
- * http://www.gnu.org/licenses/gpl.html
- */
-
-package at.bitfire.davdroid.syncadapter;
-
-import android.accounts.Account;
-import android.content.ContentValues;
-import android.content.Context;
-import android.content.SyncResult;
-import android.os.Bundle;
-import android.provider.CalendarContract.Calendars;
-import android.text.TextUtils;
-
-import org.apache.commons.codec.Charsets;
-import org.apache.commons.lang3.StringUtils;
-
-import java.io.ByteArrayInputStream;
-import java.io.IOException;
-import java.io.InputStream;
-import java.nio.charset.Charset;
-import java.util.Calendar;
-import java.util.Date;
-import java.util.HashMap;
-import java.util.LinkedList;
-import java.util.List;
-import java.util.logging.Level;
-
-import at.bitfire.dav4android.DavCalendar;
-import at.bitfire.dav4android.DavResource;
-import at.bitfire.dav4android.exception.DavException;
-import at.bitfire.dav4android.exception.HttpException;
-import at.bitfire.dav4android.property.CalendarColor;
-import at.bitfire.dav4android.property.CalendarData;
-import at.bitfire.dav4android.property.DisplayName;
-import at.bitfire.dav4android.property.GetCTag;
-import at.bitfire.dav4android.property.GetContentType;
-import at.bitfire.dav4android.property.GetETag;
-import at.bitfire.davdroid.App;
-import at.bitfire.davdroid.ArrayUtils;
-import at.bitfire.davdroid.Constants;
-import at.bitfire.davdroid.R;
-import at.bitfire.davdroid.resource.LocalCalendar;
-import at.bitfire.davdroid.resource.LocalEvent;
-import at.bitfire.davdroid.resource.LocalResource;
-import at.bitfire.ical4android.CalendarStorageException;
-import at.bitfire.ical4android.Event;
-import at.bitfire.ical4android.InvalidCalendarException;
-import at.bitfire.vcard4android.ContactsStorageException;
-import lombok.Cleanup;
-import okhttp3.HttpUrl;
-import okhttp3.MediaType;
-import okhttp3.RequestBody;
-import okhttp3.ResponseBody;
-
-public class CalendarSyncManager extends SyncManager {
-
-    protected static final int MAX_MULTIGET = 20;
-
-
-    public CalendarSyncManager(Context context, Account account, Bundle extras, String authority, SyncResult result, LocalCalendar calendar) {
-        super(Constants.NOTIFICATION_CALENDAR_SYNC, context, account, extras, authority, result);
-        localCollection = calendar;
-    }
-
-    @Override
-    protected String getSyncErrorTitle() {
-        return context.getString(R.string.sync_error_calendar, account.name);
-    }
-
-    @Override
-    protected void prepare() {
-        collectionURL = HttpUrl.parse(localCalendar().getName());
-        davCollection = new DavCalendar(httpClient, collectionURL);
-    }
-
-    @Override
-    protected void queryCapabilities() throws DavException, IOException, HttpException {
-        davCollection.propfind(0, GetCTag.NAME);
-    }
-
-    @Override
-    protected void prepareDirty() throws CalendarStorageException, ContactsStorageException {
-        super.prepareDirty();
-
-        localCalendar().processDirtyExceptions();
-    }
-
-    @Override
-    protected RequestBody prepareUpload(LocalResource resource) throws IOException, CalendarStorageException {
-        LocalEvent local = (LocalEvent)resource;
-        return RequestBody.create(
-                DavCalendar.MIME_ICALENDAR,
-                local.getEvent().toStream().toByteArray()
-        );
-    }
-
-    @Override
-    protected void listRemote() throws IOException, HttpException, DavException {
-        // calculate time range limits
-        Date limitStart = null;
-        Integer pastDays = settings.getTimeRangePastDays();
-        if (pastDays != null) {
-            Calendar calendar = Calendar.getInstance();
-            calendar.add(Calendar.DAY_OF_MONTH, -pastDays);
-            limitStart = calendar.getTime();
-        }
-
-        // fetch list of remote VEVENTs and build hash table to index file name
-        davCalendar().calendarQuery("VEVENT", limitStart, null);
-
-        remoteResources = new HashMap<>(davCollection.members.size());
-        for (DavResource iCal : davCollection.members) {
-            String fileName = iCal.fileName();
-            App.log.fine("Found remote VEVENT: " + fileName);
-            remoteResources.put(fileName, iCal);
-        }
-    }
-
-    @Override
-    protected void downloadRemote() throws IOException, HttpException, DavException, CalendarStorageException {
-        App.log.info("Downloading " + toDownload.size() + " events (" + MAX_MULTIGET + " at once)");
-
-        // download new/updated iCalendars from server
-        for (DavResource[] bunch : ArrayUtils.partition(toDownload.toArray(new DavResource[toDownload.size()]), MAX_MULTIGET)) {
-            if (Thread.interrupted())
-                return;
-            App.log.info("Downloading " + StringUtils.join(bunch, ", "));
-
-            if (bunch.length == 1) {
-                // only one contact, use GET
-                DavResource remote = bunch[0];
-
-                ResponseBody body = remote.get("text/calendar");
-                String eTag = ((GetETag)remote.properties.get(GetETag.NAME)).eTag;
-
-                Charset charset = Charsets.UTF_8;
-                MediaType contentType = body.contentType();
-                if (contentType != null)
-                    charset = contentType.charset(Charsets.UTF_8);
-
-                @Cleanup InputStream stream = body.byteStream();
-                processVEvent(remote.fileName(), eTag, stream, charset);
-
-            } else {
-                // multiple contacts, use multi-get
-                List<HttpUrl> urls = new LinkedList<>();
-                for (DavResource remote : bunch)
-                    urls.add(remote.location);
-                davCalendar().multiget(urls.toArray(new HttpUrl[urls.size()]));
-
-                // process multiget results
-                for (DavResource remote : davCollection.members) {
-                    String eTag;
-                    GetETag getETag = (GetETag)remote.properties.get(GetETag.NAME);
-                    if (getETag != null)
-                        eTag = getETag.eTag;
-                    else
-                        throw new DavException("Received multi-get response without ETag");
-
-                    Charset charset = Charsets.UTF_8;
-                    GetContentType getContentType = (GetContentType)remote.properties.get(GetContentType.NAME);
-                    if (getContentType != null && getContentType.type != null) {
-                        MediaType type = MediaType.parse(getContentType.type);
-                        if (type != null)
-                            charset = type.charset(Charsets.UTF_8);
-                    }
-
-                    CalendarData calendarData = (CalendarData)remote.properties.get(CalendarData.NAME);
-                    if (calendarData == null || calendarData.iCalendar == null)
-                        throw new DavException("Received multi-get response without address data");
-
-                    @Cleanup InputStream stream = new ByteArrayInputStream(calendarData.iCalendar.getBytes());
-                    processVEvent(remote.fileName(), eTag, stream, charset);
-                }
-            }
-        }
-    }
-
-
-    // helpers
-
-    private LocalCalendar localCalendar() { return ((LocalCalendar)localCollection); }
-    private DavCalendar davCalendar() { return (DavCalendar)davCollection; }
-
-    private void processVEvent(String fileName, String eTag, InputStream stream, Charset charset) throws IOException, CalendarStorageException {
-        Event[] events;
-        try {
-            events = Event.fromStream(stream, charset);
-        } catch (InvalidCalendarException e) {
-            App.log.log(Level.SEVERE, "Received invalid iCalendar, ignoring", e);
-            return;
-        }
-
-        if (events.length == 1) {
-            Event newData = events[0];
-
-            // delete local event, if it exists
-            LocalEvent localEvent = (LocalEvent)localResources.get(fileName);
-            if (localEvent != null) {
-                App.log.info("Updating " + fileName + " in local calendar");
-                localEvent.setETag(eTag);
-                localEvent.update(newData);
-                syncResult.stats.numUpdates++;
-            } else {
-                App.log.info("Adding " + fileName + " to local calendar");
-                localEvent = new LocalEvent(localCalendar(), newData, fileName, eTag);
-                localEvent.add();
-                syncResult.stats.numInserts++;
-            }
-        } else
-            App.log.severe("Received VCALENDAR with not exactly one VEVENT with UID, but without RECURRENCE-ID; ignoring " + fileName);
-    }
-
-}

app/src/main/java/at/bitfire/davdroid/syncadapter/CalendarSyncManager.kt

@@ -0,0 +1,210 @@
+/*
+ * Copyright © Ricki Hirner (bitfire web engineering).
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the GNU Public License v3.0
+ * which accompanies this distribution, and is available at
+ * http://www.gnu.org/licenses/gpl.html
+ */
+
+package at.bitfire.davdroid.syncadapter
+
+import android.accounts.Account
+import android.content.ContentProviderClient
+import android.content.Context
+import android.content.SyncResult
+import android.os.Bundle
+import at.bitfire.dav4android.DavCalendar
+import at.bitfire.dav4android.exception.DavException
+import at.bitfire.dav4android.property.CalendarData
+import at.bitfire.dav4android.property.GetCTag
+import at.bitfire.dav4android.property.GetETag
+import at.bitfire.davdroid.AccountSettings
+import at.bitfire.davdroid.Constants
+import at.bitfire.davdroid.R
+import at.bitfire.davdroid.log.Logger
+import at.bitfire.davdroid.resource.LocalCalendar
+import at.bitfire.davdroid.resource.LocalEvent
+import at.bitfire.davdroid.resource.LocalResource
+import at.bitfire.davdroid.settings.ISettings
+import at.bitfire.ical4android.Event
+import at.bitfire.ical4android.InvalidCalendarException
+import okhttp3.HttpUrl
+import okhttp3.RequestBody
+import org.apache.commons.collections4.ListUtils
+import java.io.ByteArrayOutputStream
+import java.io.Reader
+import java.io.StringReader
+import java.util.*
+import java.util.logging.Level
+
+/**
+ * Synchronization manager for CalDAV collections; handles events ({@code VEVENT}).
+ */
+class CalendarSyncManager(
+        context: Context,
+        settings: ISettings,
+        account: Account,
+        accountSettings: AccountSettings,
+        extras: Bundle,
+        authority: String,
+        syncResult: SyncResult,
+        val provider: ContentProviderClient,
+        val localCalendar: LocalCalendar
+): SyncManager(context, settings, account, accountSettings, extras, authority, syncResult, "calendar/${localCalendar.id}") {
+
+    companion object {
+        private val MAX_MULTIGET = 20
+    }
+
+    init {
+        localCollection = localCalendar
+    }
+
+    override fun notificationId() = Constants.NOTIFICATION_CALENDAR_SYNC
+
+    override fun getSyncErrorTitle() = context.getString(R.string.sync_error_calendar, account.name)!!
+
+
+    override fun prepare(): Boolean {
+        collectionURL = HttpUrl.parse(localCalendar.name ?: return false) ?: return false
+        davCollection = DavCalendar(httpClient.okHttpClient, collectionURL)
+        return true
+    }
+
+    override fun queryCapabilities() {
+        davCollection.propfind(0, GetCTag.NAME)
+    }
+
+    override fun prepareDirty() {
+        super.prepareDirty()
+        localCalendar.processDirtyExceptions()
+    }
+
+    override fun prepareUpload(resource: LocalResource): RequestBody {
+        if (resource is LocalEvent) {
+            val event = requireNotNull(resource.event)
+            Logger.log.log(Level.FINE, "Preparing upload of event ${resource.fileName}", event)
+
+            val os = ByteArrayOutputStream()
+            event.write(os)
+
+            return RequestBody.create(
+                    DavCalendar.MIME_ICALENDAR,
+                    os.toByteArray()
+            )
+        } else
+            throw IllegalArgumentException("resource must be a LocalEvent")
+    }
+
+    override fun listRemote() {
+        // calculate time range limits
+        var limitStart: Date? = null
+        accountSettings.getTimeRangePastDays()?.let { pastDays ->
+            val calendar = Calendar.getInstance()
+            calendar.add(Calendar.DAY_OF_MONTH, -pastDays)
+            limitStart = calendar.time
+        }
+
+        // fetch list of remote VEVENTs and build hash table to index file name
+        val calendar = davCalendar()
+        currentDavResource = calendar
+        calendar.calendarQuery("VEVENT", limitStart, null)
+
+        remoteResources = HashMap(davCollection.members.size)
+        for (iCal in davCollection.members) {
+            val fileName = iCal.fileName()
+            Logger.log.fine("Found remote VEVENT: $fileName")
+            remoteResources[fileName] = iCal
+        }
+
+        currentDavResource = null
+    }
+
+    override fun downloadRemote() {
+        Logger.log.info("Downloading ${toDownload.size} events ($MAX_MULTIGET at once)")
+
+        // download new/updated iCalendars from server
+        for (bunch in ListUtils.partition(toDownload.toList(), MAX_MULTIGET)) {
+            abortIfCancelled()
+            Logger.log.info("Downloading ${bunch.joinToString(", ")}")
+
+            if (bunch.size == 1) {
+                // only one contact, use GET
+                val remote = bunch.first()
+                currentDavResource = remote
+
+                val body = remote.get("text/calendar")
+
+                // CalDAV servers MUST return ETag on GET [https://tools.ietf.org/html/rfc4791#section-5.3.4]
+                val eTag = remote.properties[GetETag::class.java]
+                if (eTag == null || eTag.eTag.isNullOrEmpty())
+                    throw DavException("Received CalDAV GET response without ETag for ${remote.location}")
+
+                body.charStream()?.use { reader ->
+                    processVEvent(remote.fileName(), eTag.eTag!!, reader)
+                }
+
+            } else {
+                // multiple contacts, use multi-get
+                val calendar = davCalendar()
+                currentDavResource = calendar
+                calendar.multiget(bunch.map { it.location })
+
+                // process multiget results
+                for (remote in davCollection.members) {
+                    currentDavResource = remote
+
+                    val eTag = remote.properties[GetETag::class.java]?.eTag
+                            ?: throw DavException("Received multi-get response without ETag")
+
+                    val calendarData = remote.properties[CalendarData::class.java]
+                    val iCalendar = calendarData?.iCalendar
+                            ?: throw DavException("Received multi-get response without event data")
+
+                    processVEvent(remote.fileName(), eTag, StringReader(iCalendar))
+                }
+            }
+
+            currentDavResource = null
+        }
+    }
+
+
+    // helpers
+
+    private fun davCalendar() = davCollection as DavCalendar
+
+    private fun processVEvent(fileName: String, eTag: String, reader: Reader) {
+        val events: List<Event>
+        try {
+            events = Event.fromReader(reader)
+        } catch (e: InvalidCalendarException) {
+            Logger.log.log(Level.SEVERE, "Received invalid iCalendar, ignoring", e)
+            return
+        }
+
+        if (events.size == 1) {
+            val newData = events.first()
+
+            // delete local event, if it exists
+            val localEvent = localResources[fileName] as LocalEvent?
+            currentLocalResource = localEvent
+            if (localEvent != null) {
+                Logger.log.info("Updating $fileName in local calendar")
+                localEvent.eTag = eTag
+                localEvent.update(newData)
+                syncResult.stats.numUpdates++
+            } else {
+                Logger.log.info("Adding $fileName to local calendar")
+                val newEvent = LocalEvent(localCalendar, newData, fileName, eTag)
+                currentLocalResource = newEvent
+                newEvent.add()
+                syncResult.stats.numInserts++
+            }
+        } else
+            Logger.log.severe("Received VCALENDAR with not exactly one VEVENT with UID, but without RECURRENCE-ID; ignoring $fileName")
+
+        currentLocalResource = null
+    }
+
+}

app/src/main/java/at/bitfire/davdroid/syncadapter/CalendarsSyncAdapterService.java

@@ -1,125 +0,0 @@
-/*
- * Copyright © 2013 – 2015 Ricki Hirner (bitfire web engineering).
- * All rights reserved. This program and the accompanying materials
- * are made available under the terms of the GNU Public License v3.0
- * which accompanies this distribution, and is available at
- * http://www.gnu.org/licenses/gpl.html
- */
-package at.bitfire.davdroid.syncadapter;
-
-import android.accounts.Account;
-import android.app.Service;
-import android.content.AbstractThreadedSyncAdapter;
-import android.content.ContentProviderClient;
-import android.content.ContentValues;
-import android.content.Context;
-import android.content.Intent;
-import android.content.SyncResult;
-import android.database.Cursor;
-import android.database.DatabaseUtils;
-import android.database.sqlite.SQLiteDatabase;
-import android.os.Bundle;
-import android.os.IBinder;
-import android.provider.CalendarContract;
-
-import java.util.LinkedHashMap;
-import java.util.Map;
-import java.util.logging.Level;
-
-import at.bitfire.davdroid.App;
-import at.bitfire.davdroid.model.CollectionInfo;
-import at.bitfire.davdroid.model.ServiceDB.Collections;
-import at.bitfire.davdroid.model.ServiceDB.OpenHelper;
-import at.bitfire.davdroid.model.ServiceDB.Services;
-import at.bitfire.davdroid.resource.LocalCalendar;
-import at.bitfire.ical4android.CalendarStorageException;
-import lombok.Cleanup;
-
-public class CalendarsSyncAdapterService extends SyncAdapterService {
-
-    @Override
-    public void onCreate() {
-        super.onCreate();
-        syncAdapter = new SyncAdapter(this, dbHelper);
-    }
-
-
-	private static class SyncAdapter extends SyncAdapterService.SyncAdapter {
-
-        public SyncAdapter(Context context, OpenHelper dbHelper) {
-            super(context, dbHelper);
-        }
-
-        @Override
-        public void onPerformSync(Account account, Bundle extras, String authority, ContentProviderClient provider, SyncResult syncResult) {
-            super.onPerformSync(account, extras, authority, provider, syncResult);
-
-            try {
-                updateLocalCalendars(provider, account);
-
-                for (LocalCalendar calendar : (LocalCalendar[])LocalCalendar.find(account, provider, LocalCalendar.Factory.INSTANCE, CalendarContract.Calendars.SYNC_EVENTS + "!=0", null)) {
-                    App.log.info("Synchronizing calendar #"  + calendar.getId() + ", URL: " + calendar.getName());
-                    CalendarSyncManager syncManager = new CalendarSyncManager(getContext(), account, extras, authority, syncResult, calendar);
-                    syncManager.performSync();
-                }
-            } catch (CalendarStorageException e) {
-                App.log.log(Level.SEVERE, "Couldn't enumerate local calendars", e);
-            }
-
-            App.log.info("Calendar sync complete");
-        }
-
-        private void updateLocalCalendars(ContentProviderClient provider, Account account) throws CalendarStorageException {
-            long service = getService(account);
-
-            // enumerate remote and local calendars
-            Map<String, CollectionInfo> remote = remoteCalendars(service);
-            LocalCalendar[] local = (LocalCalendar[])LocalCalendar.find(account, provider, LocalCalendar.Factory.INSTANCE, null, null);
-
-            // delete obsolete local calendar
-            for (LocalCalendar calendar : local) {
-                String url = calendar.getName();
-                if (!remote.containsKey(url)) {
-                    App.log.fine("Deleting obsolete local calendar " + url);
-                    calendar.delete();
-                } else {
-                    // remote CollectionInfo found for this local collection, update data
-                    CollectionInfo info = remote.get(url);
-                    App.log.fine("Updating local calendar " + url + " with " + info);
-                    calendar.update(info);
-                    // we already have a local calendar for this remote collection, don't take into consideration anymore
-                    remote.remove(url);
-                }
-            }
-
-            // create new local calendars
-            for (String url : remote.keySet()) {
-                CollectionInfo info = remote.get(url);
-                App.log.info("Adding local calendar list " + info);
-                LocalCalendar.create(account, provider, info);
-            }
-        }
-
-        long getService(Account account) {
-            @Cleanup Cursor c = db.query(Services._TABLE, new String[]{ Services.ID },
-                    Services.ACCOUNT_NAME + "=? AND " + Services.SERVICE + "=?", new String[]{account.name, Services.SERVICE_CALDAV}, null, null, null);
-            c.moveToNext();
-            return c.getLong(0);
-        }
-
-        private Map<String, CollectionInfo> remoteCalendars(long service) {
-            Map<String, CollectionInfo> collections = new LinkedHashMap<>();
-            @Cleanup Cursor cursor = db.query(Collections._TABLE, Collections._COLUMNS,
-                    Collections.SERVICE_ID + "=? AND " + Collections.SUPPORTS_VEVENT + "!=0 AND " + Collections.SYNC,
-                    new String[] { String.valueOf(service) }, null, null, null);
-            while (cursor.moveToNext()) {
-                ContentValues values = new ContentValues();
-                DatabaseUtils.cursorRowToContentValues(cursor, values);
-                CollectionInfo info = CollectionInfo.fromDB(values);
-                collections.put(info.url, info);
-            }
-            return collections;
-        }
-    }
-
-}

app/src/main/java/at/bitfire/davdroid/syncadapter/CalendarsSyncAdapterService.kt

@@ -0,0 +1,127 @@
+/*
+ * Copyright © Ricki Hirner (bitfire web engineering).
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the GNU Public License v3.0
+ * which accompanies this distribution, and is available at
+ * http://www.gnu.org/licenses/gpl.html
+ */
+package at.bitfire.davdroid.syncadapter
+
+import android.accounts.Account
+import android.content.*
+import android.database.DatabaseUtils
+import android.os.Bundle
+import android.provider.CalendarContract
+import at.bitfire.davdroid.AccountSettings
+import at.bitfire.davdroid.log.Logger
+import at.bitfire.davdroid.model.CollectionInfo
+import at.bitfire.davdroid.model.ServiceDB
+import at.bitfire.davdroid.model.ServiceDB.Collections
+import at.bitfire.davdroid.resource.LocalCalendar
+import at.bitfire.davdroid.settings.ISettings
+import at.bitfire.ical4android.AndroidCalendar
+import java.util.logging.Level
+
+class CalendarsSyncAdapterService: SyncAdapterService() {
+
+    override fun syncAdapter() = CalendarsSyncAdapter(this)
+
+
+	class CalendarsSyncAdapter(
+            context: Context
+    ): SyncAdapter(context) {
+
+        override fun sync(settings: ISettings, account: Account, extras: Bundle, authority: String, provider: ContentProviderClient, syncResult: SyncResult) {
+            try {
+                val accountSettings = AccountSettings(context, settings, account)
+
+                /* don't run sync if
+                   - sync conditions (e.g. "sync only in WiFi") are not met AND
+                   - this is is an automatic sync (i.e. manual syncs are run regardless of sync conditions)
+                 */
+                if (!extras.containsKey(ContentResolver.SYNC_EXTRAS_MANUAL) && !checkSyncConditions(accountSettings))
+                    return
+
+                if (accountSettings.getEventColors())
+                    AndroidCalendar.insertColors(provider, account)
+                else
+                    AndroidCalendar.removeColors(provider, account)
+
+                updateLocalCalendars(provider, account, accountSettings)
+
+                for (calendar in AndroidCalendar.find(account, provider, LocalCalendar.Factory, "${CalendarContract.Calendars.SYNC_EVENTS}!=0", null)) {
+                    Logger.log.info("Synchronizing calendar #${calendar.id}, URL: ${calendar.name}")
+                    CalendarSyncManager(context, settings, account, accountSettings, extras, authority, syncResult, provider, calendar).use {
+                        it.performSync()
+                    }
+                }
+            } catch(e: Exception) {
+                Logger.log.log(Level.SEVERE, "Couldn't sync calendars", e)
+            }
+            Logger.log.info("Calendar sync complete")
+        }
+
+        private fun updateLocalCalendars(provider: ContentProviderClient, account: Account, settings: AccountSettings) {
+            ServiceDB.OpenHelper(context).use { dbHelper ->
+                val db = dbHelper.readableDatabase
+
+                fun getService() =
+                        db.query(ServiceDB.Services._TABLE, arrayOf(ServiceDB.Services.ID),
+                                "${ServiceDB.Services.ACCOUNT_NAME}=? AND ${ServiceDB.Services.SERVICE}=?",
+                                arrayOf(account.name, ServiceDB.Services.SERVICE_CALDAV), null, null, null)?.use { c ->
+                            if (c.moveToNext())
+                                c.getLong(0)
+                            else
+                                null
+                        }
+
+                fun remoteCalendars(service: Long?): MutableMap<String, CollectionInfo> {
+                    val collections = mutableMapOf<String, CollectionInfo>()
+                    service?.let {
+                        db.query(Collections._TABLE, null,
+                                "${Collections.SERVICE_ID}=? AND ${Collections.SUPPORTS_VEVENT}!=0 AND ${Collections.SYNC}",
+                                arrayOf(service.toString()), null, null, null).use { cursor ->
+                            while (cursor.moveToNext()) {
+                                val values = ContentValues(cursor.columnCount)
+                                DatabaseUtils.cursorRowToContentValues(cursor, values)
+                                val info = CollectionInfo(values)
+                                collections[info.url] = info
+                            }
+                        }
+                    }
+                    return collections
+                }
+
+                // enumerate remote and local calendars
+                val service = getService()
+                val remote = remoteCalendars(service)
+
+                // delete/update local calendars
+                val updateColors = settings.getManageCalendarColors()
+
+                for (calendar in AndroidCalendar.find(account, provider, LocalCalendar.Factory, null, null))
+                    calendar.name?.let { url ->
+                        val info = remote[url]
+                        if (info == null) {
+                            Logger.log.log(Level.INFO, "Deleting obsolete local calendar", url)
+                            calendar.delete()
+                        } else {
+                            // remote CollectionInfo found for this local collection, update data
+                            Logger.log.log(Level.FINE, "Updating local calendar $url", info)
+                            calendar.update(info, updateColors)
+                            // we already have a local calendar for this remote collection, don't take into consideration anymore
+                            remote -= url
+                        }
+                    }
+
+                // create new local calendars
+                for ((_, info) in remote) {
+                    Logger.log.log(Level.INFO, "Adding local calendar", info)
+                    LocalCalendar.create(account, provider, info)
+                }
+            }
+        }
+
+    }
+
+}

app/src/main/java/at/bitfire/davdroid/syncadapter/ContactsSyncAdapterService.java

@@ -1,92 +0,0 @@
-/*
- * Copyright © 2013 – 2015 Ricki Hirner (bitfire web engineering).
- * All rights reserved. This program and the accompanying materials
- * are made available under the terms of the GNU Public License v3.0
- * which accompanies this distribution, and is available at
- * http://www.gnu.org/licenses/gpl.html
- */
-package at.bitfire.davdroid.syncadapter;
-
-import android.accounts.Account;
-import android.app.Service;
-import android.content.AbstractThreadedSyncAdapter;
-import android.content.ContentProviderClient;
-import android.content.ContentValues;
-import android.content.Context;
-import android.content.Intent;
-import android.content.SyncResult;
-import android.database.Cursor;
-import android.database.DatabaseUtils;
-import android.database.sqlite.SQLiteDatabase;
-import android.os.Bundle;
-import android.os.IBinder;
-import android.support.annotation.NonNull;
-import android.support.annotation.Nullable;
-
-import java.util.List;
-
-import at.bitfire.davdroid.AccountSettings;
-import at.bitfire.davdroid.App;
-import at.bitfire.davdroid.model.CollectionInfo;
-import at.bitfire.davdroid.model.ServiceDB;
-import at.bitfire.davdroid.model.ServiceDB.Collections;
-import at.bitfire.davdroid.model.ServiceDB.OpenHelper;
-import lombok.Cleanup;
-
-public class ContactsSyncAdapterService extends SyncAdapterService {
-
-	@Override
-	public void onCreate() {
-        super.onCreate();
-        syncAdapter = new ContactsSyncAdapter(this, dbHelper);
-	}
-
-
-	private static class ContactsSyncAdapter extends SyncAdapter {
-
-        public ContactsSyncAdapter(Context context, OpenHelper dbHelper) {
-            super(context, dbHelper);
-        }
-
-        @Override
-        public void onPerformSync(Account account, Bundle extras, String authority, ContentProviderClient provider, SyncResult syncResult) {
-            super.onPerformSync(account, extras, authority, provider, syncResult);
-
-            Long service = getService(account);
-            if (service != null) {
-                CollectionInfo remote = remoteAddressBook(service);
-                if (remote != null) {
-                    ContactsSyncManager syncManager = new ContactsSyncManager(getContext(), account, extras, authority, provider, syncResult, remote);
-                    syncManager.performSync();
-                } else
-                    App.log.info("No address book collection selected for synchronization");
-            }
-
-            App.log.info("Address book sync complete");
-        }
-
-        @Nullable
-        private Long getService(@NonNull Account account) {
-            @Cleanup Cursor c = db.query(ServiceDB.Services._TABLE, new String[] { ServiceDB.Services.ID },
-                    ServiceDB.Services.ACCOUNT_NAME + "=? AND " + ServiceDB.Services.SERVICE + "=?", new String[] { account.name, ServiceDB.Services.SERVICE_CARDDAV }, null, null, null);
-            if (c.moveToNext())
-                return c.getLong(0);
-            else
-                return null;
-        }
-
-        @Nullable
-        private CollectionInfo remoteAddressBook(long service) {
-            @Cleanup Cursor c = db.query(Collections._TABLE, Collections._COLUMNS,
-                    Collections.SERVICE_ID + "=? AND " + Collections.SYNC, new String[] { String.valueOf(service) }, null, null, null);
-            if (c.moveToNext()) {
-                ContentValues values = new ContentValues();
-                DatabaseUtils.cursorRowToContentValues(c, values);
-                return CollectionInfo.fromDB(values);
-            } else
-                return null;
-        }
-
-    }
-
-}

app/src/main/java/at/bitfire/davdroid/syncadapter/ContactsSyncAdapterService.kt

@@ -0,0 +1,75 @@
+/*
+ * Copyright © Ricki Hirner (bitfire web engineering).
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the GNU Public License v3.0
+ * which accompanies this distribution, and is available at
+ * http://www.gnu.org/licenses/gpl.html
+ */
+
+package at.bitfire.davdroid.syncadapter
+
+import android.accounts.Account
+import android.content.ContentProviderClient
+import android.content.ContentResolver
+import android.content.Context
+import android.content.SyncResult
+import android.os.Bundle
+import android.provider.ContactsContract
+import at.bitfire.davdroid.AccountSettings
+import at.bitfire.davdroid.log.Logger
+import at.bitfire.davdroid.resource.LocalAddressBook
+import at.bitfire.davdroid.settings.ISettings
+import java.util.logging.Level
+
+class ContactsSyncAdapterService: SyncAdapterService() {
+
+    companion object {
+        val PREVIOUS_GROUP_METHOD = "previous_group_method"
+    }
+
+    override fun syncAdapter() = ContactsSyncAdapter(this)
+
+
+	class ContactsSyncAdapter(
+            context: Context
+    ): SyncAdapter(context) {
+
+        override fun sync(settings: ISettings, account: Account, extras: Bundle, authority: String, provider: ContentProviderClient, syncResult: SyncResult) {
+            try {
+                val addressBook = LocalAddressBook(context, account, provider)
+                val accountSettings = AccountSettings(context, settings, addressBook.getMainAccount())
+
+                // handle group method change
+                val groupMethod = accountSettings.getGroupMethod().name
+                accountSettings.accountManager.getUserData(account, PREVIOUS_GROUP_METHOD)?.let { previousGroupMethod ->
+                    if (previousGroupMethod != groupMethod) {
+                        Logger.log.info("Group method changed, deleting all local contacts/groups")
+
+                        // delete all local contacts and groups so that they will be downloaded again
+                        provider.delete(addressBook.syncAdapterURI(ContactsContract.RawContacts.CONTENT_URI), null, null)
+                        provider.delete(addressBook.syncAdapterURI(ContactsContract.Groups.CONTENT_URI), null, null)
+
+                        // reset CTag
+                        addressBook.setCTag(null)
+                    }
+                }
+                accountSettings.accountManager.setUserData(account, PREVIOUS_GROUP_METHOD, groupMethod)
+
+                if (!extras.containsKey(ContentResolver.SYNC_EXTRAS_MANUAL) && !checkSyncConditions(accountSettings))
+                    return
+
+                Logger.log.info("Synchronizing address book: ${addressBook.getURL()}")
+                Logger.log.info("Taking settings from: ${addressBook.getMainAccount()}")
+
+                ContactsSyncManager(context, settings, account, accountSettings, extras, authority, syncResult, provider, addressBook).use {
+                    it.performSync()
+                }
+            } catch(e: Exception) {
+                Logger.log.log(Level.SEVERE, "Couldn't sync contacts", e)
+            }
+            Logger.log.info("Contacts sync complete")
+        }
+
+    }
+
+}

app/src/main/java/at/bitfire/davdroid/syncadapter/ContactsSyncManager.java

@@ -1,325 +0,0 @@
-/*
- * Copyright © 2013 – 2015 Ricki Hirner (bitfire web engineering).
- * All rights reserved. This program and the accompanying materials
- * are made available under the terms of the GNU Public License v3.0
- * which accompanies this distribution, and is available at
- * http://www.gnu.org/licenses/gpl.html
- */
-
-package at.bitfire.davdroid.syncadapter;
-
-import android.accounts.Account;
-import android.content.ContentProviderClient;
-import android.content.Context;
-import android.content.SyncResult;
-import android.os.Bundle;
-
-import org.apache.commons.codec.Charsets;
-import org.apache.commons.lang3.StringUtils;
-
-import java.io.ByteArrayInputStream;
-import java.io.IOException;
-import java.io.InputStream;
-import java.nio.charset.Charset;
-import java.util.HashMap;
-import java.util.LinkedList;
-import java.util.List;
-import java.util.logging.Level;
-
-import at.bitfire.dav4android.DavAddressBook;
-import at.bitfire.dav4android.DavResource;
-import at.bitfire.dav4android.exception.DavException;
-import at.bitfire.dav4android.exception.HttpException;
-import at.bitfire.dav4android.property.AddressData;
-import at.bitfire.dav4android.property.GetCTag;
-import at.bitfire.dav4android.property.GetContentType;
-import at.bitfire.dav4android.property.GetETag;
-import at.bitfire.dav4android.property.SupportedAddressData;
-import at.bitfire.davdroid.App;
-import at.bitfire.davdroid.ArrayUtils;
-import at.bitfire.davdroid.Constants;
-import at.bitfire.davdroid.HttpClient;
-import at.bitfire.davdroid.R;
-import at.bitfire.davdroid.model.CollectionInfo;
-import at.bitfire.davdroid.resource.LocalAddressBook;
-import at.bitfire.davdroid.resource.LocalContact;
-import at.bitfire.davdroid.resource.LocalGroup;
-import at.bitfire.davdroid.resource.LocalResource;
-import at.bitfire.ical4android.CalendarStorageException;
-import at.bitfire.vcard4android.Contact;
-import at.bitfire.vcard4android.ContactsStorageException;
-import ezvcard.VCardVersion;
-import ezvcard.util.IOUtils;
-import lombok.Cleanup;
-import lombok.RequiredArgsConstructor;
-import okhttp3.HttpUrl;
-import okhttp3.MediaType;
-import okhttp3.OkHttpClient;
-import okhttp3.Request;
-import okhttp3.RequestBody;
-import okhttp3.Response;
-import okhttp3.ResponseBody;
-
-public class ContactsSyncManager extends SyncManager {
-    protected static final int MAX_MULTIGET = 10;
-
-    final private ContentProviderClient provider;
-    final private CollectionInfo remote;
-    private boolean hasVCard4;
-
-
-    public ContactsSyncManager(Context context, Account account, Bundle extras, String authority, ContentProviderClient provider, SyncResult result, CollectionInfo remote) {
-        super(Constants.NOTIFICATION_CONTACTS_SYNC, context, account, extras, authority, result);
-        this.provider = provider;
-        this.remote = remote;
-    }
-
-    @Override
-    protected String getSyncErrorTitle() {
-        return context.getString(R.string.sync_error_contacts, account.name);
-    }
-
-
-    @Override
-    protected void prepare() throws ContactsStorageException {
-        // prepare local address book
-        localCollection = new LocalAddressBook(account, provider);
-
-        String url = remote.url;
-        String lastUrl = localAddressBook().getURL();
-        if (!url.equals(lastUrl)) {
-            App.log.info("Selected address book has changed from " + lastUrl + " to " + url + ", deleting all local contacts");
-            ((LocalAddressBook)localCollection).deleteAll();
-        }
-
-        collectionURL = HttpUrl.parse(url);
-        davCollection = new DavAddressBook(httpClient, collectionURL);
-
-        processChangedGroups();
-    }
-
-    @Override
-    protected void queryCapabilities() throws DavException, IOException, HttpException {
-        // prepare remote address book
-        hasVCard4 = false;
-        davCollection.propfind(0, SupportedAddressData.NAME, GetCTag.NAME);
-        SupportedAddressData supportedAddressData = (SupportedAddressData) davCollection.properties.get(SupportedAddressData.NAME);
-        if (supportedAddressData != null)
-            for (MediaType type : supportedAddressData.types)
-                if ("text/vcard; version=4.0".equalsIgnoreCase(type.toString()))
-                    hasVCard4 = true;
-        App.log.info("Server advertises VCard/4 support: " + hasVCard4);
-    }
-
-    @Override
-    protected RequestBody prepareUpload(LocalResource resource) throws IOException, ContactsStorageException {
-        LocalContact local = (LocalContact)resource;
-        return RequestBody.create(
-                hasVCard4 ? DavAddressBook.MIME_VCARD4 : DavAddressBook.MIME_VCARD3_UTF8,
-                local.getContact().toStream(hasVCard4 ? VCardVersion.V4_0 : VCardVersion.V3_0).toByteArray()
-        );
-    }
-
-    @Override
-    protected void listRemote() throws IOException, HttpException, DavException {
-        // fetch list of remote VCards and build hash table to index file name
-
-        try {
-            davAddressBook().addressbookQuery();
-        } catch(HttpException e) {
-            /*  non-successful responses to CARDDAV:addressbook-query with empty filter, tested on 2015/10/21
-             *  fastmail.com                 403 Forbidden (DAV:error CARDDAV:supported-filter)
-             *  mailbox.org (OpenXchange)    400 Bad Request
-             *  SOGo                         207 Multi-status, but without entries       http://www.sogo.nu/bugs/view.php?id=3370
-             *  Zimbra ZCS                   500 Server Error                            https://bugzilla.zimbra.com/show_bug.cgi?id=101902
-             */
-            if (e.status == 400 || e.status == 403 || e.status == 500 || e.status == 501) {
-                App.log.log(Level.WARNING, "Server error on REPORT addressbook-query, falling back to PROPFIND", e);
-                davAddressBook().propfind(1, GetETag.NAME);
-            } else
-                // no defined fallback, pass through exception
-                throw e;
-        }
-
-        remoteResources = new HashMap<>(davCollection.members.size());
-        for (DavResource vCard : davCollection.members) {
-            String fileName = vCard.fileName();
-            App.log.fine("Found remote VCard: " + fileName);
-            remoteResources.put(fileName, vCard);
-        }
-    }
-
-    @Override
-    protected void downloadRemote() throws IOException, HttpException, DavException, ContactsStorageException {
-        App.log.info("Downloading " + toDownload.size() + " contacts (" + MAX_MULTIGET + " at once)");
-
-        // prepare downloader which may be used to download external resource like contact photos
-        Contact.Downloader downloader = new ResourceDownloader(collectionURL);
-
-        // download new/updated VCards from server
-        for (DavResource[] bunch : ArrayUtils.partition(toDownload.toArray(new DavResource[toDownload.size()]), MAX_MULTIGET)) {
-            if (Thread.interrupted())
-                return;
-
-            App.log.info("Downloading " + StringUtils.join(bunch, ", "));
-
-            if (bunch.length == 1) {
-                // only one contact, use GET
-                DavResource remote = bunch[0];
-
-                ResponseBody body = remote.get("text/vcard;version=4.0, text/vcard;charset=utf-8;q=0.8, text/vcard;q=0.5");
-                String eTag = ((GetETag) remote.properties.get(GetETag.NAME)).eTag;
-
-                Charset charset = Charsets.UTF_8;
-                MediaType contentType = body.contentType();
-                if (contentType != null)
-                    charset = contentType.charset(Charsets.UTF_8);
-
-                @Cleanup InputStream stream = body.byteStream();
-                processVCard(remote.fileName(), eTag, stream, charset, downloader);
-
-            } else {
-                // multiple contacts, use multi-get
-                List<HttpUrl> urls = new LinkedList<>();
-                for (DavResource remote : bunch)
-                    urls.add(remote.location);
-                davAddressBook().multiget(urls.toArray(new HttpUrl[urls.size()]), hasVCard4);
-
-                // process multiget results
-                for (DavResource remote : davCollection.members) {
-                    String eTag;
-                    GetETag getETag = (GetETag) remote.properties.get(GetETag.NAME);
-                    if (getETag != null)
-                        eTag = getETag.eTag;
-                    else
-                        throw new DavException("Received multi-get response without ETag");
-
-                    Charset charset = Charsets.UTF_8;
-                    GetContentType getContentType = (GetContentType) remote.properties.get(GetContentType.NAME);
-                    if (getContentType != null && getContentType.type != null) {
-                        MediaType type = MediaType.parse(getContentType.type);
-                        if (type != null)
-                            charset = type.charset(Charsets.UTF_8);
-                    }
-
-                    AddressData addressData = (AddressData) remote.properties.get(AddressData.NAME);
-                    if (addressData == null || addressData.vCard == null)
-                        throw new DavException("Received multi-get response without address data");
-
-                    @Cleanup InputStream stream = new ByteArrayInputStream(addressData.vCard.getBytes());
-                    processVCard(remote.fileName(), eTag, stream, charset, downloader);
-                }
-            }
-        }
-    }
-
-    @Override
-    protected void saveSyncState() throws CalendarStorageException, ContactsStorageException {
-        super.saveSyncState();
-        ((LocalAddressBook)localCollection).setURL(remote.url);
-    }
-
-
-    // helpers
-
-    private DavAddressBook davAddressBook() { return (DavAddressBook)davCollection; }
-    private LocalAddressBook localAddressBook() { return (LocalAddressBook)localCollection; }
-
-    private void processChangedGroups() throws ContactsStorageException {
-        LocalAddressBook addressBook = localAddressBook();
-
-        // groups with DELETED=1: remove group finally
-        for (LocalGroup group : addressBook.getDeletedGroups()) {
-            long groupId = group.getId();
-            App.log.fine("Finally removing group #" + groupId);
-            // remove group memberships, but not as sync adapter (should marks contacts as DIRTY)
-            // NOTE: doesn't work that way because Contact Provider removes the group memberships even for DELETED groups
-            // addressBook.removeGroupMemberships(groupId, false);
-            group.delete();
-        }
-
-        // groups with DIRTY=1: mark all memberships as dirty, then clean DIRTY flag of group
-        for (LocalGroup group : addressBook.getDirtyGroups()) {
-            long groupId = group.getId();
-            App.log.fine("Marking members of modified group #" + groupId + " as dirty");
-            addressBook.markMembersDirty(groupId);
-            group.clearDirty();
-        }
-    }
-
-    private void processVCard(String fileName, String eTag, InputStream stream, Charset charset, Contact.Downloader downloader) throws IOException, ContactsStorageException {
-        Contact[] contacts = Contact.fromStream(stream, charset, downloader);
-        if (contacts.length == 1) {
-            Contact newData = contacts[0];
-
-            // update local contact, if it exists
-            LocalContact localContact = (LocalContact)localResources.get(fileName);
-            if (localContact != null) {
-                App.log.info("Updating " + fileName + " in local address book");
-                localContact.eTag = eTag;
-                localContact.update(newData);
-                syncResult.stats.numUpdates++;
-            } else {
-                App.log.info("Adding " + fileName + " to local address book");
-                localContact = new LocalContact(localAddressBook(), newData, fileName, eTag);
-                localContact.add();
-                syncResult.stats.numInserts++;
-            }
-        } else
-            App.log.severe("Received VCard with not exactly one VCARD, ignoring " + fileName);
-    }
-
-
-    // downloader helper class
-
-    @RequiredArgsConstructor
-    private class ResourceDownloader implements Contact.Downloader {
-        final HttpUrl baseUrl;
-
-        @Override
-        public byte[] download(String url, String accepts) {
-            HttpUrl httpUrl = HttpUrl.parse(url);
-
-            if (httpUrl == null) {
-                App.log.log(Level.SEVERE, "Invalid external resource URL", url);
-                return null;
-            }
-
-            String host = httpUrl.host();
-            if (host == null) {
-                App.log.log(Level.SEVERE, "External resource URL doesn't specify a host name", url);
-                return null;
-            }
-
-            OkHttpClient resourceClient = HttpClient.create(context, null);
-
-            // authenticate only against a certain host, and only upon request
-            resourceClient = HttpClient.addAuthentication(resourceClient, baseUrl.host(), settings.username(), settings.password());
-
-            // allow redirects
-            resourceClient = resourceClient.newBuilder()
-                    .followRedirects(true)
-                    .build();
-
-            try {
-                Response response = resourceClient.newCall(new Request.Builder()
-                        .get()
-                        .url(httpUrl)
-                        .build()).execute();
-
-                ResponseBody body = response.body();
-                if (body != null) {
-                    @Cleanup InputStream stream = body.byteStream();
-                    if (response.isSuccessful() && stream != null) {
-                        return IOUtils.toByteArray(stream);
-                    } else
-                        App.log.severe("Couldn't download external resource");
-                }
-            } catch(IOException e) {
-                App.log.log(Level.SEVERE, "Couldn't download external resource", e);
-            }
-            return null;
-        }
-    }
-
-}

app/src/main/java/at/bitfire/davdroid/syncadapter/ContactsSyncManager.kt

@@ -0,0 +1,508 @@
+/*
+ * Copyright © Ricki Hirner (bitfire web engineering).
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the GNU Public License v3.0
+ * which accompanies this distribution, and is available at
+ * http://www.gnu.org/licenses/gpl.html
+ */
+
+package at.bitfire.davdroid.syncadapter
+
+import android.accounts.Account
+import android.content.*
+import android.os.Build
+import android.os.Bundle
+import android.os.RemoteException
+import android.provider.ContactsContract.Groups
+import android.support.v4.app.NotificationCompat
+import at.bitfire.dav4android.DavAddressBook
+import at.bitfire.dav4android.exception.DavException
+import at.bitfire.dav4android.property.*
+import at.bitfire.davdroid.*
+import at.bitfire.davdroid.log.Logger
+import at.bitfire.davdroid.resource.LocalAddressBook
+import at.bitfire.davdroid.resource.LocalContact
+import at.bitfire.davdroid.resource.LocalGroup
+import at.bitfire.davdroid.resource.LocalResource
+import at.bitfire.davdroid.settings.ISettings
+import at.bitfire.davdroid.ui.NotificationUtils
+import at.bitfire.vcard4android.BatchOperation
+import at.bitfire.vcard4android.Contact
+import at.bitfire.vcard4android.ContactsStorageException
+import at.bitfire.vcard4android.GroupMethod
+import ezvcard.VCardVersion
+import okhttp3.HttpUrl
+import okhttp3.Request
+import okhttp3.RequestBody
+import org.apache.commons.collections4.ListUtils
+import java.io.*
+import java.util.*
+import java.util.logging.Level
+
+/**
+ * Synchronization manager for CardDAV collections; handles contacts and groups.
+ *
+ * Group handling differs according to the {@link #groupMethod}. There are two basic methods to
+ * handle/manage groups:
+ *
+ *     1. CATEGORIES: groups memberships are attached to each contact and represented as
+ *     "category". When a group is dirty or has been deleted, all its members have to be set to
+ *     dirty, too (because they have to be uploaded without the respective category). This
+ *     is done in [prepareDirty]. Empty groups can be deleted without further processing,
+ *     which is done in [postProcess] because groups may become empty after downloading
+ *     updated remote contacts.
+ *
+ *     2. Groups as separate VCards: individual and group contacts (with a list of member UIDs) are
+ *     distinguished. When a local group is dirty, its members don't need to be set to dirty.
+ *
+ *         * However, when a contact is dirty, it has
+ *         to be checked whether its group memberships have changed. In this case, the respective
+ *         groups have to be set to dirty. For instance, if contact A is in group G and H, and then
+ *         group membership of G is removed, the contact will be set to dirty because of the changed
+ *         [android.provider.ContactsContract.CommonDataKinds.GroupMembership]. DAVdroid will
+ *         then have to check whether the group memberships have actually changed, and if so,
+ *         all affected groups have to be set to dirty. To detect changes in group memberships,
+ *         DAVdroid always mirrors all [android.provider.ContactsContract.CommonDataKinds.GroupMembership]
+ *         data rows in respective [at.bitfire.vcard4android.CachedGroupMembership] rows.
+ *         If the cached group memberships are not the same as the current group member ships, the
+ *         difference set (in our example G, because its in the cached memberships, but not in the
+ *         actual ones) is marked as dirty. This is done in [prepareDirty].
+ *
+ *         * When downloading remote contacts, groups (+ member information) may be received
+ *         by the actual members. Thus, the member lists have to be cached until all VCards
+ *         are received. This is done by caching the member UIDs of each group in
+ *         [LocalGroup.COLUMN_PENDING_MEMBERS]. In [postProcess],
+ *         these "pending memberships" are assigned to the actual contacts and then cleaned up.
+ */
+class ContactsSyncManager(
+        context: Context,
+        settings: ISettings,
+        account: Account,
+        accountSettings: AccountSettings,
+        extras: Bundle,
+        authority: String,
+        syncResult: SyncResult,
+        val provider: ContentProviderClient,
+        private val localAddressBook: LocalAddressBook
+): SyncManager(context, settings, account, accountSettings, extras, authority, syncResult, "addressBook") {
+
+    companion object {
+        private val MAX_MULTIGET = 10
+    }
+
+    private val readOnly = localAddressBook.getReadOnly()
+    private var numDiscarded = 0
+
+    private var hasVCard4 = false
+    private val groupMethod = accountSettings.getGroupMethod()
+
+
+    init {
+        localCollection = localAddressBook
+    }
+
+    override fun notificationId() = Constants.NOTIFICATION_CONTACTS_SYNC
+
+    override fun getSyncErrorTitle() = context.getString(R.string.sync_error_contacts, account.name)!!
+
+
+    override fun prepare(): Boolean {
+        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.N && Build.VERSION.SDK_INT < Build.VERSION_CODES.O) {
+            // workaround for Android 7 which sets DIRTY flag when only meta-data is changed
+            val reallyDirty = localAddressBook.verifyDirty()
+            val deleted = localAddressBook.getDeleted().size
+            if (extras.containsKey(ContentResolver.SYNC_EXTRAS_UPLOAD) && reallyDirty == 0 && deleted == 0) {
+                Logger.log.info("This sync was called to up-sync dirty/deleted contacts, but no contacts have been changed")
+                return false
+            }
+        }
+
+        collectionURL = HttpUrl.parse(localAddressBook.getURL()) ?: return false
+        davCollection = DavAddressBook(httpClient.okHttpClient, collectionURL)
+
+        return true
+    }
+
+    override fun queryCapabilities() {
+        // prepare remote address book
+        davCollection.propfind(0, SupportedAddressData.NAME, GetCTag.NAME)
+
+        val properties = davCollection.properties
+        properties[SupportedAddressData::class.java]?.let {
+            hasVCard4 = it.hasVCard4()
+        }
+        Logger.log.info("Server advertises VCard/4 support: $hasVCard4")
+
+        Logger.log.info("Contact group method: $groupMethod")
+        // in case of GROUP_VCARDs, treat groups as contacts in the local address book
+        localAddressBook.includeGroups = groupMethod == GroupMethod.GROUP_VCARDS
+    }
+
+    override fun processLocallyDeleted() {
+        if (readOnly) {
+            for (group in localAddressBook.getDeletedGroups()) {
+                Logger.log.warning("Restoring locally deleted group (read-only address book!)")
+                group.resetDeleted()
+                numDiscarded++
+            }
+
+            for (contact in localAddressBook.getDeletedContacts()) {
+                Logger.log.warning("Restoring locally deleted contact (read-only address book!)")
+                contact.resetDeleted()
+                numDiscarded++
+            }
+
+            if (numDiscarded > 0)
+                notifyDiscardedChange()
+        } else
+            // mirror deletions to remote collection (DELETE)
+            super.processLocallyDeleted()
+    }
+
+    override fun prepareDirty() {
+        // generate UID/file name for newly created contacts
+        super.prepareDirty()
+
+        if (readOnly) {
+            for (group in localAddressBook.getDirtyGroups()) {
+                Logger.log.warning("Resetting locally modified group to ETag=null (read-only address book!)")
+                group.clearDirty(null)
+                numDiscarded++
+            }
+
+            for (contact in localAddressBook.getDirtyContacts()) {
+                Logger.log.warning("Resetting locally modified contact to ETag=null (read-only address book!)")
+                contact.clearDirty(null)
+                numDiscarded++
+            }
+
+            if (numDiscarded > 0)
+                notifyDiscardedChange()
+
+        } else {
+            if (groupMethod == GroupMethod.CATEGORIES) {
+                /* groups memberships are represented as contact CATEGORIES */
+
+                // groups with DELETED=1: set all members to dirty, then remove group
+                for (group in localAddressBook.getDeletedGroups()) {
+                    Logger.log.fine("Finally removing group $group")
+                    // useless because Android deletes group memberships as soon as a group is set to DELETED:
+                    // group.markMembersDirty()
+                    group.delete()
+                }
+
+                // groups with DIRTY=1: mark all memberships as dirty, then clean DIRTY flag of group
+                for (group in localAddressBook.getDirtyGroups()) {
+                    Logger.log.fine("Marking members of modified group $group as dirty")
+                    group.markMembersDirty()
+                    group.clearDirty(null)
+                }
+            } else {
+                /* groups as separate VCards: there are group contacts and individual contacts */
+
+                // mark groups with changed members as dirty
+                val batch = BatchOperation(localAddressBook.provider!!)
+                for (contact in localAddressBook.getDirtyContacts())
+                    try {
+                        Logger.log.fine("Looking for changed group memberships of contact ${contact.fileName}")
+                        val cachedGroups = contact.getCachedGroupMemberships()
+                        val currentGroups = contact.getGroupMemberships()
+                        for (groupID in cachedGroups disjunct currentGroups) {
+                            Logger.log.fine("Marking group as dirty: $groupID")
+                            batch.enqueue(BatchOperation.Operation(
+                                    ContentProviderOperation.newUpdate(localAddressBook.syncAdapterURI(ContentUris.withAppendedId(Groups.CONTENT_URI, groupID)))
+                                    .withValue(Groups.DIRTY, 1)
+                                    .withYieldAllowed(true)
+                            ))
+                        }
+                    } catch(e: FileNotFoundException) {
+                    }
+                batch.commit()
+            }
+        }
+    }
+
+    private fun notifyDiscardedChange() {
+        val notification = NotificationCompat.Builder(context, NotificationUtils.CHANNEL_SYNC_STATUS)
+                .setSmallIcon(R.drawable.ic_delete_notification)
+                .setLargeIcon(App.getLauncherBitmap(context))
+                .setContentTitle(context.getString(R.string.sync_contacts_read_only_address_book))
+                .setContentText(context.resources.getQuantityString(R.plurals.sync_contacts_local_contact_changes_discarded, numDiscarded, numDiscarded))
+                .setSubText(account.name)
+                .setCategory(NotificationCompat.CATEGORY_ERROR)
+                .setPriority(NotificationCompat.PRIORITY_LOW)
+                .setLocalOnly(true)
+                .setAutoCancel(true)
+                .build()
+        notificationManager.notify("discarded_${account.name}", 0, notification)
+    }
+
+    override fun prepareUpload(resource: LocalResource): RequestBody {
+        val contact: Contact
+        if (resource is LocalContact) {
+            contact = resource.contact!!
+
+            if (groupMethod == GroupMethod.CATEGORIES) {
+                // add groups as CATEGORIES
+                for (groupID in resource.getGroupMemberships()) {
+                    try {
+                        provider.query(
+                                localAddressBook.syncAdapterURI(ContentUris.withAppendedId(Groups.CONTENT_URI, groupID)),
+                                arrayOf(Groups.TITLE), null, null, null
+                        )?.use { cursor ->
+                            if (cursor.moveToNext()) {
+                                val title = cursor.getString(0)
+                                if (!title.isNullOrEmpty())
+                                    contact.categories.add(title)
+                            }
+                        }
+                    } catch(e: RemoteException) {
+                        throw ContactsStorageException("Couldn't find group for adding CATEGORIES", e)
+                    }
+                }
+            }
+        } else if (resource is LocalGroup)
+            contact = resource.contact!!
+        else
+            throw IllegalArgumentException("resource must be a LocalContact or a LocalGroup")
+
+        Logger.log.log(Level.FINE, "Preparing upload of VCard ${resource.fileName}", contact)
+
+        val os = ByteArrayOutputStream()
+        contact.write(if (hasVCard4) VCardVersion.V4_0 else VCardVersion.V3_0, groupMethod, os)
+
+        return RequestBody.create(
+                if (hasVCard4) DavAddressBook.MIME_VCARD4 else DavAddressBook.MIME_VCARD3_UTF8,
+                os.toByteArray()
+        )
+    }
+
+    override fun listRemote() {
+        val addressBook = davAddressBook()
+        currentDavResource = addressBook
+
+        // fetch list of remote VCards and build hash table to index file name
+        addressBook.propfind(1, ResourceType.NAME, GetETag.NAME)
+
+        remoteResources = HashMap(davCollection.members.size)
+        for (vCard in davCollection.members) {
+            // ignore member collections
+            var ignore = false
+            vCard.properties[ResourceType::class.java]?.let { type ->
+                if (type.types.contains(ResourceType.COLLECTION))
+                    ignore = true
+            }
+            if (ignore)
+                continue
+
+            val fileName = vCard.fileName()
+            Logger.log.fine("Found remote VCard: $fileName")
+            remoteResources[fileName] = vCard
+        }
+
+        currentDavResource = null
+    }
+
+    override fun downloadRemote() {
+        Logger.log.info("Downloading ${toDownload.size} contacts ($MAX_MULTIGET at once)")
+
+        // prepare downloader which may be used to download external resource like contact photos
+        val downloader = ResourceDownloader(collectionURL)
+
+        // download new/updated VCards from server
+        for (bunch in ListUtils.partition(toDownload.toList(), MAX_MULTIGET)) {
+            abortIfCancelled()
+            Logger.log.info("Downloading ${bunch.joinToString(", ")}")
+
+            if (bunch.size == 1) {
+                // only one contact, use GET
+                val remote = bunch.first()
+                currentDavResource = remote
+
+                val body = remote.get("text/vcard;version=4.0, text/vcard;charset=utf-8;q=0.8, text/vcard;q=0.5")
+
+                // CardDAV servers MUST return ETag on GET [https://tools.ietf.org/html/rfc6352#section-6.3.2.3]
+                val eTag = remote.properties[GetETag::class.java]
+                if (eTag == null || eTag.eTag.isNullOrEmpty())
+                    throw DavException("Received CardDAV GET response without ETag for ${remote.location}")
+
+                body.charStream().use { reader ->
+                    processVCard(remote.fileName(), eTag.eTag!!, reader, downloader)
+                }
+
+            } else {
+                // multiple contacts, use multi-get
+                val addressBook = davAddressBook()
+                currentDavResource = addressBook
+                addressBook.multiget(bunch.map { it.location }, hasVCard4)
+
+                // process multi-get results
+                for (remote in davCollection.members) {
+                    currentDavResource = remote
+
+                    val eTag = remote.properties[GetETag::class.java]?.eTag
+                            ?: throw DavException("Received multi-get response without ETag")
+
+                    val addressData = remote.properties[AddressData::class.java]
+                    val vCard = addressData?.vCard
+                            ?: throw DavException("Received multi-get response without address data")
+
+                    processVCard(remote.fileName(), eTag, StringReader(vCard), downloader)
+                }
+            }
+
+            currentDavResource = null
+        }
+    }
+
+    override fun postProcess() {
+        if (groupMethod == GroupMethod.CATEGORIES) {
+            /* VCard3 group handling: groups memberships are represented as contact CATEGORIES */
+
+            // remove empty groups
+            Logger.log.info("Removing empty groups")
+            localAddressBook.removeEmptyGroups()
+
+        } else {
+            /* VCard4 group handling: there are group contacts and individual contacts */
+            Logger.log.info("Assigning memberships of downloaded contact groups")
+            LocalGroup.applyPendingMemberships(localAddressBook)
+        }
+    }
+
+
+    // helpers
+
+    private fun davAddressBook() = davCollection as DavAddressBook
+
+    private fun processVCard(fileName: String, eTag: String, reader: Reader, downloader: Contact.Downloader) {
+        Logger.log.info("Processing CardDAV resource $fileName")
+        val contacts = Contact.fromReader(reader, downloader)
+        if (contacts.isEmpty()) {
+            Logger.log.warning("Received VCard without data, ignoring")
+            return
+        } else if (contacts.size > 1)
+            Logger.log.warning("Received multiple VCards, using first one")
+
+        val newData = contacts.first()
+
+        if (groupMethod == GroupMethod.CATEGORIES && newData.group) {
+            Logger.log.warning("Received group VCard although group method is CATEGORIES. Saving as regular contact")
+            newData.group = false
+        }
+
+        // update local contact, if it exists
+        var local = localResources[fileName]
+        currentLocalResource = local
+        if (local != null) {
+            Logger.log.log(Level.INFO, "Updating $fileName in local address book", newData)
+
+            if (local is LocalGroup && newData.group) {
+                // update group
+                local.eTag = eTag
+                local.updateFromServer(newData)
+                syncResult.stats.numUpdates++
+
+            } else if (local is LocalContact && !newData.group) {
+                // update contact
+                local.eTag = eTag
+                local.update(newData)
+                syncResult.stats.numUpdates++
+
+            } else {
+                // group has become an individual contact or vice versa
+                local.delete()
+                local = null
+            }
+        }
+
+        if (local == null) {
+            if (newData.group) {
+                Logger.log.log(Level.INFO, "Creating local group", newData)
+                val group = LocalGroup(localAddressBook, newData, fileName, eTag)
+                currentLocalResource = group
+                group.create()
+
+                local = group
+            } else {
+                Logger.log.log(Level.INFO, "Creating local contact", newData)
+                val contact = LocalContact(localAddressBook, newData, fileName, eTag)
+                currentLocalResource = contact
+                contact.create()
+
+                local = contact
+            }
+            syncResult.stats.numInserts++
+        }
+
+        if (groupMethod == GroupMethod.CATEGORIES && local is LocalContact) {
+            // VCard3: update group memberships from CATEGORIES
+            currentLocalResource = local
+
+            val batch = BatchOperation(provider)
+            Logger.log.log(Level.FINE, "Removing contact group memberships")
+            local.removeGroupMemberships(batch)
+
+            for (category in local.contact!!.categories) {
+                val groupID = localAddressBook.findOrCreateGroup(category)
+                Logger.log.log(Level.FINE, "Adding membership in group $category ($groupID)")
+                local.addToGroup(batch, groupID)
+            }
+
+            batch.commit()
+        }
+
+        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.N && Build.VERSION.SDK_INT < Build.VERSION_CODES.O && local is LocalContact)
+            // workaround for Android 7 which sets DIRTY flag when only meta-data is changed
+            local.updateHashCode(null)
+
+        currentLocalResource = null
+    }
+
+
+    // downloader helper class
+
+    private inner class ResourceDownloader(
+            val baseUrl: HttpUrl
+    ): Contact.Downloader {
+
+        override fun download(url: String, accepts: String): ByteArray? {
+            val httpUrl = HttpUrl.parse(url)
+            if (httpUrl == null) {
+                Logger.log.log(Level.SEVERE, "Invalid external resource URL", url)
+                return null
+            }
+
+            val host = httpUrl.host()
+            if (host == null) {
+                Logger.log.log(Level.SEVERE, "External resource URL doesn't specify a host name", url)
+                return null
+            }
+
+            // authenticate only against a certain host, and only upon request
+            val builder = HttpClient.Builder(context, baseUrl.host(), accountSettings.credentials())
+
+            // allow redirects
+            builder.followRedirects(true)
+
+            val client = builder.build()
+            try {
+                val response = client.okHttpClient.newCall(Request.Builder()
+                        .get()
+                        .url(httpUrl)
+                        .build()).execute()
+
+                if (response.isSuccessful)
+                    return response.body()?.bytes()
+                else
+                    Logger.log.warning("Couldn't download external resource")
+            } catch(e: IOException) {
+                Logger.log.log(Level.SEVERE, "Couldn't download external resource", e)
+            } finally {
+                client.close()
+            }
+            return null
+        }
+    }
+
+}

app/src/main/java/at/bitfire/davdroid/syncadapter/NullAuthenticatorService.kt

@@ -0,0 +1,53 @@
+/*
+ * Copyright © Ricki Hirner (bitfire web engineering).
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the GNU Public License v3.0
+ * which accompanies this distribution, and is available at
+ * http://www.gnu.org/licenses/gpl.html
+ */
+package at.bitfire.davdroid.syncadapter
+
+import android.accounts.AbstractAccountAuthenticator
+import android.accounts.Account
+import android.accounts.AccountAuthenticatorResponse
+import android.accounts.AccountManager
+import android.app.Service
+import android.content.Context
+import android.content.Intent
+import android.os.Bundle
+import at.bitfire.davdroid.ui.AccountsActivity
+
+class NullAuthenticatorService: Service() {
+
+    private lateinit var accountAuthenticator: AccountAuthenticator
+
+    override fun onCreate() {
+        accountAuthenticator = AccountAuthenticator(this)
+    }
+
+    override fun onBind(intent: Intent?) =
+            accountAuthenticator.iBinder.takeIf { intent?.action == android.accounts.AccountManager.ACTION_AUTHENTICATOR_INTENT }
+
+
+    private class AccountAuthenticator(
+            val context: Context
+    ): AbstractAccountAuthenticator(context) {
+
+        override fun addAccount(response: AccountAuthenticatorResponse?, accountType: String?, authTokenType: String?, requiredFeatures: Array<String>?, options: Bundle?): Bundle {
+            val intent = Intent(context, AccountsActivity::class.java)
+            intent.putExtra(AccountManager.KEY_ACCOUNT_AUTHENTICATOR_RESPONSE, response)
+            val bundle = Bundle(1)
+            bundle.putParcelable(AccountManager.KEY_INTENT, intent)
+            return bundle
+        }
+
+        override fun editProperties(response: AccountAuthenticatorResponse?, accountType: String?) = null
+        override fun getAuthTokenLabel(p0: String?) = null
+        override fun confirmCredentials(p0: AccountAuthenticatorResponse?, p1: Account?, p2: Bundle?) = null
+        override fun updateCredentials(p0: AccountAuthenticatorResponse?, p1: Account?, p2: String?, p3: Bundle?) = null
+        override fun getAuthToken(p0: AccountAuthenticatorResponse?, p1: Account?, p2: String?, p3: Bundle?) = null
+        override fun hasFeatures(p0: AccountAuthenticatorResponse?, p1: Account?, p2: Array<out String>?) = null
+
+    }
+
+}

app/src/main/java/at/bitfire/davdroid/syncadapter/SyncAdapterService.java

@@ -1,69 +0,0 @@
-/*
- * Copyright © 2013 – 2016 Ricki Hirner (bitfire web engineering).
- * All rights reserved. This program and the accompanying materials
- * are made available under the terms of the GNU Public License v3.0
- * which accompanies this distribution, and is available at
- * http://www.gnu.org/licenses/gpl.html
- */
-
-package at.bitfire.davdroid.syncadapter;
-
-import android.accounts.Account;
-import android.app.Service;
-import android.content.AbstractThreadedSyncAdapter;
-import android.content.ContentProviderClient;
-import android.content.Context;
-import android.content.Intent;
-import android.content.SyncResult;
-import android.database.sqlite.SQLiteDatabase;
-import android.os.Bundle;
-import android.os.IBinder;
-import android.support.annotation.Nullable;
-
-import at.bitfire.davdroid.AccountSettings;
-import at.bitfire.davdroid.App;
-import at.bitfire.davdroid.model.ServiceDB;
-
-public abstract class SyncAdapterService extends Service {
-
-    ServiceDB.OpenHelper dbHelper;
-    AbstractThreadedSyncAdapter syncAdapter;
-
-    @Override
-    public void onCreate() {
-        dbHelper = new ServiceDB.OpenHelper(this);
-    }
-
-    @Override
-    public void onDestroy() {
-        dbHelper.close();
-    }
-
-    @Nullable
-    @Override
-    public IBinder onBind(Intent intent) {
-        return syncAdapter.getSyncAdapterBinder();
-    }
-
-
-    public static abstract class SyncAdapter extends AbstractThreadedSyncAdapter {
-        protected final SQLiteDatabase db;
-
-        public SyncAdapter(Context context, ServiceDB.OpenHelper dbHelper) {
-            super(context, false);
-            db = dbHelper.getReadableDatabase();
-        }
-
-        @Override
-        public void onPerformSync(Account account, Bundle extras, String authority, ContentProviderClient provider, SyncResult syncResult) {
-            App.log.info("Starting " + authority + " sync");
-
-            // required for dav4android (ServiceLoader)
-            Thread.currentThread().setContextClassLoader(getContext().getClassLoader());
-
-            // peek into AccountSettings to cause possible migration (v0.9 -> v1.0)
-            new AccountSettings(getContext(), account);
-        }
-    }
-
-}

app/src/main/java/at/bitfire/davdroid/syncadapter/SyncAdapterService.kt

@@ -0,0 +1,120 @@
+/*
+ * Copyright © Ricki Hirner (bitfire web engineering).
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the GNU Public License v3.0
+ * which accompanies this distribution, and is available at
+ * http://www.gnu.org/licenses/gpl.html
+ */
+
+package at.bitfire.davdroid.syncadapter
+
+import android.accounts.Account
+import android.app.PendingIntent
+import android.app.Service
+import android.content.*
+import android.net.ConnectivityManager
+import android.net.wifi.WifiManager
+import android.os.Bundle
+import android.support.v4.app.NotificationCompat
+import at.bitfire.davdroid.AccountSettings
+import at.bitfire.davdroid.App
+import at.bitfire.davdroid.Constants
+import at.bitfire.davdroid.R
+import at.bitfire.davdroid.log.Logger
+import at.bitfire.davdroid.settings.ISettings
+import at.bitfire.davdroid.settings.Settings
+import at.bitfire.davdroid.ui.NotificationUtils
+import at.bitfire.davdroid.ui.PermissionsActivity
+import java.util.*
+import java.util.logging.Level
+
+abstract class SyncAdapterService: Service() {
+
+    companion object {
+        val runningSyncs = Collections.synchronizedSet(mutableSetOf<Pair<String, Account>>())!!
+    }
+
+    abstract protected fun syncAdapter(): AbstractThreadedSyncAdapter
+
+    override fun onBind(intent: Intent?) = syncAdapter().syncAdapterBinder!!
+
+
+    abstract class SyncAdapter(
+            context: Context
+    ): AbstractThreadedSyncAdapter(context, false) {
+
+        abstract fun sync(settings: ISettings, account: Account, extras: Bundle, authority: String, provider: ContentProviderClient, syncResult: SyncResult)
+
+        override fun onPerformSync(account: Account, extras: Bundle, authority: String, provider: ContentProviderClient, syncResult: SyncResult) {
+            Logger.log.log(Level.INFO, "$authority sync of $account has been initiated", extras.keySet().joinToString(", "))
+
+            // prevent multiple syncs of the same authority to be run for the same account
+            val currentSync = Pair(authority, account)
+            if (!runningSyncs.add(currentSync)) {
+                Logger.log.warning("There's already another $authority sync running for $account, aborting")
+                return
+            }
+
+            try {
+                // required for dav4android (ServiceLoader)
+                Thread.currentThread().contextClassLoader = context.classLoader
+
+                // load app settings
+                Settings.getInstance(context).use { settings ->
+                    if (settings == null) {
+                        syncResult.databaseError = true
+                        Logger.log.severe("Couldn't connect to Settings service, aborting sync")
+                        return
+                    }
+
+                    sync(settings, account, extras, authority, provider, syncResult)
+                }
+                Logger.log.info("Sync for $authority complete")
+            } finally {
+                runningSyncs -= currentSync
+            }
+        }
+
+        override fun onSecurityException(account: Account, extras: Bundle, authority: String, syncResult: SyncResult) {
+            Logger.log.log(Level.WARNING, "Security exception when opening content provider for $authority")
+            syncResult.databaseError = true
+
+            val intent = Intent(context, PermissionsActivity::class.java)
+            intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK)
+
+            val notify = NotificationCompat.Builder(context, NotificationUtils.CHANNEL_SYNC_PROBLEMS)
+                    .setSmallIcon(R.drawable.ic_sync_error_notification)
+                    .setLargeIcon(App.getLauncherBitmap(context))
+                    .setContentTitle(context.getString(R.string.sync_error_permissions))
+                    .setContentText(context.getString(R.string.sync_error_permissions_text))
+                    .setContentIntent(PendingIntent.getActivity(context, 0, intent, PendingIntent.FLAG_UPDATE_CURRENT))
+                    .setCategory(NotificationCompat.CATEGORY_ERROR)
+                    .build()
+            val nm = NotificationUtils.createChannels(context)
+            nm.notify(Constants.NOTIFICATION_PERMISSIONS, notify)
+        }
+
+        protected fun checkSyncConditions(settings: AccountSettings): Boolean {
+            if (settings.getSyncWifiOnly()) {
+                val connectivityManager = context.getSystemService(CONNECTIVITY_SERVICE) as ConnectivityManager
+                val network = connectivityManager.activeNetworkInfo
+                if (network == null || network.type != ConnectivityManager.TYPE_WIFI || !network.isConnected) {
+                    Logger.log.info("Not on connected WiFi, stopping")
+                    return false
+                }
+
+                settings.getSyncWifiOnlySSIDs()?.let { onlySSIDs ->
+                    val wifi = context.applicationContext.getSystemService(WIFI_SERVICE) as WifiManager
+                    val info = wifi.connectionInfo
+                    if (info == null || !onlySSIDs.contains(info.ssid.trim('"'))) {
+                        Logger.log.info("Connected to wrong WiFi network (${info.ssid}), ignoring")
+                        return false
+                    }
+                }
+            }
+            return true
+        }
+
+    }
+
+}

app/src/main/java/at/bitfire/davdroid/syncadapter/SyncManager.java

@@ -1,434 +0,0 @@
-    /*
- * Copyright © 2013 – 2015 Ricki Hirner (bitfire web engineering).
- * All rights reserved. This program and the accompanying materials
- * are made available under the terms of the GNU Public License v3.0
- * which accompanies this distribution, and is available at
- * http://www.gnu.org/licenses/gpl.html
- */
-package at.bitfire.davdroid.syncadapter;
-
-import android.accounts.Account;
-import android.annotation.TargetApi;
-import android.app.Notification;
-import android.app.NotificationManager;
-import android.app.PendingIntent;
-import android.content.ContentResolver;
-import android.content.Context;
-import android.content.Intent;
-import android.content.SyncResult;
-import android.os.Build;
-import android.os.Bundle;
-import android.support.v7.app.NotificationCompat;
-import android.text.TextUtils;
-
-import java.io.IOException;
-import java.util.Date;
-import java.util.HashMap;
-import java.util.HashSet;
-import java.util.Map;
-import java.util.Set;
-import java.util.UUID;
-import java.util.logging.Level;
-
-import at.bitfire.dav4android.DavResource;
-import at.bitfire.dav4android.exception.ConflictException;
-import at.bitfire.dav4android.exception.DavException;
-import at.bitfire.dav4android.exception.HttpException;
-import at.bitfire.dav4android.exception.PreconditionFailedException;
-import at.bitfire.dav4android.exception.ServiceUnavailableException;
-import at.bitfire.dav4android.exception.UnauthorizedException;
-import at.bitfire.dav4android.property.GetCTag;
-import at.bitfire.dav4android.property.GetETag;
-import at.bitfire.davdroid.AccountSettings;
-import at.bitfire.davdroid.App;
-import at.bitfire.davdroid.HttpClient;
-import at.bitfire.davdroid.R;
-import at.bitfire.davdroid.resource.LocalCollection;
-import at.bitfire.davdroid.resource.LocalResource;
-import at.bitfire.davdroid.ui.AccountActivity;
-import at.bitfire.davdroid.ui.AccountSettingsActivity;
-import at.bitfire.davdroid.ui.DebugInfoActivity;
-import at.bitfire.ical4android.CalendarStorageException;
-import at.bitfire.vcard4android.ContactsStorageException;
-import okhttp3.HttpUrl;
-import okhttp3.OkHttpClient;
-import okhttp3.RequestBody;
-
-abstract public class SyncManager {
-
-    protected final int SYNC_PHASE_PREPARE = 0,
-                        SYNC_PHASE_QUERY_CAPABILITIES = 1,
-                        SYNC_PHASE_PROCESS_LOCALLY_DELETED = 2,
-                        SYNC_PHASE_PREPARE_DIRTY = 3,
-                        SYNC_PHASE_UPLOAD_DIRTY = 4,
-                        SYNC_PHASE_CHECK_SYNC_STATE = 5,
-                        SYNC_PHASE_LIST_LOCAL = 6,
-                        SYNC_PHASE_LIST_REMOTE = 7,
-                        SYNC_PHASE_COMPARE_LOCAL_REMOTE = 8,
-                        SYNC_PHASE_DOWNLOAD_REMOTE = 9,
-                        SYNC_PHASE_SAVE_SYNC_STATE = 10;
-
-    protected final NotificationManager notificationManager;
-    protected final int notificationId;
-
-    protected final Context context;
-    protected final Account account;
-    protected final Bundle extras;
-    protected final String authority;
-    protected final SyncResult syncResult;
-
-    protected final AccountSettings settings;
-    protected LocalCollection localCollection;
-
-    protected OkHttpClient httpClient;
-    protected HttpUrl collectionURL;
-    protected DavResource davCollection;
-
-
-    /** remote CTag at the time of {@link #listRemote()} */
-    protected String remoteCTag = null;
-
-    /** sync-able resources in the local collection, as enumerated by {@link #listLocal()} */
-    protected Map<String, LocalResource> localResources;
-
-    /** sync-able resources in the remote collection, as enumerated by {@link #listRemote()} */
-    protected Map<String, DavResource> remoteResources;
-
-    /** resources which have changed on the server, as determined by {@link #compareLocalRemote()} */
-    protected Set<DavResource> toDownload;
-
-
-
-    public SyncManager(int notificationId, Context context, Account account, Bundle extras, String authority, SyncResult syncResult) {
-        this.context = context;
-        this.account = account;
-        this.extras = extras;
-        this.authority = authority;
-        this.syncResult = syncResult;
-
-        // get account settings (for sync interval etc.)
-        settings = new AccountSettings(context, account);
-
-        // create HttpClient with given logger
-        httpClient = HttpClient.create(context, account);
-
-        // dismiss previous error notifications
-        notificationManager = (NotificationManager)context.getSystemService(Context.NOTIFICATION_SERVICE);
-        notificationManager.cancel(account.name, this.notificationId = notificationId);
-    }
-
-    protected abstract String getSyncErrorTitle();
-
-    @TargetApi(21)
-    public void performSync() {
-        int syncPhase = SYNC_PHASE_PREPARE;
-        try {
-            App.log.info("Preparing synchronization");
-            prepare();
-
-            if (Thread.interrupted())
-                return;
-            syncPhase = SYNC_PHASE_QUERY_CAPABILITIES;
-            App.log.info("Querying capabilities");
-            queryCapabilities();
-
-            syncPhase = SYNC_PHASE_PROCESS_LOCALLY_DELETED;
-            App.log.info("Processing locally deleted entries");
-            processLocallyDeleted();
-
-            if (Thread.interrupted())
-                return;
-            syncPhase = SYNC_PHASE_PREPARE_DIRTY;
-            App.log.info("Locally preparing dirty entries");
-            prepareDirty();
-
-            syncPhase = SYNC_PHASE_UPLOAD_DIRTY;
-            App.log.info("Uploading dirty entries");
-            uploadDirty();
-
-            syncPhase = SYNC_PHASE_CHECK_SYNC_STATE;
-            App.log.info("Checking sync state");
-            if (checkSyncState()) {
-                syncPhase = SYNC_PHASE_LIST_LOCAL;
-                App.log.info("Listing local entries");
-                listLocal();
-
-                if (Thread.interrupted())
-                    return;
-                syncPhase = SYNC_PHASE_LIST_REMOTE;
-                App.log.info("Listing remote entries");
-                listRemote();
-
-                if (Thread.interrupted())
-                    return;
-                syncPhase = SYNC_PHASE_COMPARE_LOCAL_REMOTE;
-                App.log.info("Comparing local/remote entries");
-                compareLocalRemote();
-
-                syncPhase = SYNC_PHASE_DOWNLOAD_REMOTE;
-                App.log.info("Downloading remote entries");
-                downloadRemote();
-
-                syncPhase = SYNC_PHASE_SAVE_SYNC_STATE;
-                App.log.info("Saving sync state");
-                saveSyncState();
-            } else
-                App.log.info("Remote collection didn't change, skipping remote sync");
-
-        } catch (IOException|ServiceUnavailableException e) {
-            App.log.log(Level.WARNING, "I/O exception during sync, trying again later", e);
-            syncResult.stats.numIoExceptions++;
-
-            if (e instanceof ServiceUnavailableException) {
-                Date retryAfter = ((ServiceUnavailableException) e).retryAfter;
-                if (retryAfter != null) {
-                    // how many seconds to wait? getTime() returns ms, so divide by 1000
-                    syncResult.delayUntil = (retryAfter.getTime() - new Date().getTime()) / 1000;
-                }
-            }
-
-        } catch(Exception e) {
-            final int messageString;
-
-            if (e instanceof UnauthorizedException) {
-                App.log.log(Level.SEVERE, "Not authorized anymore", e);
-                messageString = R.string.sync_error_unauthorized;
-                syncResult.stats.numAuthExceptions++;
-            } else if (e instanceof HttpException || e instanceof DavException) {
-                App.log.log(Level.SEVERE, "HTTP/DAV Exception during sync", e);
-                messageString = R.string.sync_error_http_dav;
-                syncResult.stats.numParseExceptions++;
-            } else if (e instanceof CalendarStorageException || e instanceof ContactsStorageException) {
-                App.log.log(Level.SEVERE, "Couldn't access local storage", e);
-                messageString = R.string.sync_error_local_storage;
-                syncResult.databaseError = true;
-            } else {
-                App.log.log(Level.SEVERE, "Unknown sync error", e);
-                messageString = R.string.sync_error;
-                syncResult.stats.numParseExceptions++;
-            }
-
-            final Intent detailsIntent;
-            if (e instanceof UnauthorizedException) {
-                detailsIntent = new Intent(context, AccountSettingsActivity.class);
-                detailsIntent.putExtra(AccountSettingsActivity.EXTRA_ACCOUNT, account);
-            } else {
-                detailsIntent = new Intent(context, DebugInfoActivity.class);
-                detailsIntent.putExtra(DebugInfoActivity.KEY_EXCEPTION, e);
-                detailsIntent.putExtra(DebugInfoActivity.KEY_ACCOUNT, account);
-                detailsIntent.putExtra(DebugInfoActivity.KEY_AUTHORITY, authority);
-                detailsIntent.putExtra(DebugInfoActivity.KEY_PHASE, syncPhase);
-            }
-
-            NotificationCompat.Builder builder = new NotificationCompat.Builder(context);
-            builder .setSmallIcon(R.drawable.ic_launcher)
-                    .setContentTitle(getSyncErrorTitle())
-                    .setContentIntent(PendingIntent.getActivity(context, notificationId, detailsIntent, PendingIntent.FLAG_UPDATE_CURRENT))
-                    .setCategory(NotificationCompat.CATEGORY_ERROR)
-                    .setLocalOnly(true);
-
-            try {
-                String[] phases = context.getResources().getStringArray(R.array.sync_error_phases);
-                String message = context.getString(messageString, phases[syncPhase]);
-                builder.setContentText(message);
-            } catch (IndexOutOfBoundsException ex) {
-                // should never happen
-            }
-
-            notificationManager.notify(account.name, notificationId, builder.build());
-        }
-    }
-
-
-    abstract protected void prepare() throws ContactsStorageException;
-
-    abstract protected void queryCapabilities() throws IOException, HttpException, DavException, CalendarStorageException, ContactsStorageException;
-
-    /**
-     * Process locally deleted entries (DELETE them on the server as well).
-     * Checks Thread.interrupted() before each request to allow quick sync cancellation.
-     */
-    protected void processLocallyDeleted() throws CalendarStorageException, ContactsStorageException {
-        // Remove locally deleted entries from server (if they have a name, i.e. if they were uploaded before),
-        // but only if they don't have changed on the server. Then finally remove them from the local address book.
-        LocalResource[] localList = localCollection.getDeleted();
-        for (LocalResource local : localList) {
-            if (Thread.interrupted())
-                return;
-
-            final String fileName = local.getFileName();
-            if (!TextUtils.isEmpty(fileName)) {
-                App.log.info(fileName + " has been deleted locally -> deleting from server");
-                try {
-                    new DavResource(httpClient, collectionURL.newBuilder().addPathSegment(fileName).build())
-                            .delete(local.getETag());
-                } catch (IOException|HttpException e) {
-                    App.log.warning("Couldn't delete " + fileName + " from server; ignoring (may be downloaded again)");
-                }
-            } else
-                App.log.info("Removing local record #" + local.getId() + " which has been deleted locally and was never uploaded");
-            local.delete();
-            syncResult.stats.numDeletes++;
-        }
-    }
-
-    protected void prepareDirty() throws CalendarStorageException, ContactsStorageException {
-        // assign file names and UIDs to new contacts so that we can use the file name as an index
-        for (LocalResource local : localCollection.getWithoutFileName()) {
-            String uuid = UUID.randomUUID().toString();
-            App.log.info("Found local record #" + local.getId() + " without file name; assigning file name/UID based on " + uuid);
-            local.updateFileNameAndUID(uuid);
-        }
-    }
-
-    abstract protected RequestBody prepareUpload(LocalResource resource) throws IOException, CalendarStorageException, ContactsStorageException;
-
-    /**
-     * Uploads dirty records to the server, using a PUT request for each record.
-     * Checks Thread.interrupted() before each request to allow quick sync cancellation.
-     */
-    protected void uploadDirty() throws IOException, HttpException, CalendarStorageException, ContactsStorageException {
-        // upload dirty contacts
-        for (LocalResource local : localCollection.getDirty()) {
-            if (Thread.interrupted())
-                return;
-
-            final String fileName = local.getFileName();
-
-            DavResource remote = new DavResource(httpClient, collectionURL.newBuilder().addPathSegment(fileName).build());
-
-            // generate entity to upload (VCard, iCal, whatever)
-            RequestBody body = prepareUpload(local);
-
-            try {
-
-                if (local.getETag() == null) {
-                    App.log.info("Uploading new record " + fileName);
-                    remote.put(body, null, true);
-                } else {
-                    App.log.info("Uploading locally modified record " + fileName);
-                    remote.put(body, local.getETag(), false);
-                }
-
-            } catch (ConflictException|PreconditionFailedException e) {
-                // we can't interact with the user to resolve the conflict, so we treat 409 like 412
-                App.log.log(Level.INFO, "Resource has been modified on the server before upload, ignoring", e);
-            }
-
-            String eTag = null;
-            GetETag newETag = (GetETag) remote.properties.get(GetETag.NAME);
-            if (newETag != null) {
-                eTag = newETag.eTag;
-                App.log.fine("Received new ETag=" + eTag + " after uploading");
-            } else
-                App.log.fine("Didn't receive new ETag after uploading, setting to null");
-
-            local.clearDirty(eTag);
-        }
-    }
-
-    /**
-     * Checks the current sync state (e.g. CTag) and whether synchronization from remote is required.
-     * @return <ul>
-     *      <li><code>true</code>   if the remote collection has changed, i.e. synchronization from remote is required</li>
-     *      <li><code>false</code>  if the remote collection hasn't changed</li>
-     * </ul>
-     */
-    protected boolean checkSyncState() throws CalendarStorageException, ContactsStorageException {
-        // check CTag (ignore on manual sync)
-        GetCTag getCTag = (GetCTag)davCollection.properties.get(GetCTag.NAME);
-        if (getCTag != null)
-            remoteCTag = getCTag.cTag;
-
-        String localCTag = null;
-        if (extras.containsKey(ContentResolver.SYNC_EXTRAS_MANUAL))
-            App.log.info("Manual sync, ignoring CTag");
-        else
-            localCTag = localCollection.getCTag();
-
-        if (remoteCTag != null && remoteCTag.equals(localCTag)) {
-            App.log.info("Remote collection didn't change (CTag=" + remoteCTag + "), no need to query children");
-            return false;
-        } else
-            return true;
-    }
-
-    /**
-     * Lists all local resources which should be taken into account for synchronization into {@link #localResources}.
-     */
-    protected void listLocal() throws CalendarStorageException, ContactsStorageException {
-        // fetch list of local contacts and build hash table to index file name
-        LocalResource[] localList = localCollection.getAll();
-        localResources = new HashMap<>(localList.length);
-        for (LocalResource resource : localList) {
-            App.log.fine("Found local resource: " + resource.getFileName());
-            localResources.put(resource.getFileName(), resource);
-        }
-    }
-
-    /**
-     * Lists all members of the remote collection which should be taken into account for synchronization into {@link #remoteResources}.
-     */
-    abstract protected void listRemote() throws IOException, HttpException, DavException;
-
-    /**
-     * Compares {@link #localResources} and {@link #remoteResources} by file name and ETag:
-     * <ul>
-     *     <li>Local resources which are not available in the remote collection (anymore) will be removed.</li>
-     *     <li>Resources whose remote ETag has changed will be added into {@link #toDownload}</li>
-     * </ul>
-     */
-    protected void compareLocalRemote() throws IOException, HttpException, DavException, CalendarStorageException, ContactsStorageException {
-        /* check which contacts
-           1. are not present anymore remotely -> delete immediately on local side
-           2. updated remotely -> add to downloadNames
-           3. added remotely  -> add to downloadNames
-         */
-        toDownload = new HashSet<>();
-        for (String localName : localResources.keySet()) {
-            DavResource remote = remoteResources.get(localName);
-            if (remote == null) {
-                App.log.info(localName + " is not on server anymore, deleting");
-                localResources.get(localName).delete();
-                syncResult.stats.numDeletes++;
-            } else {
-                // contact is still on server, check whether it has been updated remotely
-                GetETag getETag = (GetETag)remote.properties.get(GetETag.NAME);
-                if (getETag == null || getETag.eTag == null)
-                    throw new DavException("Server didn't provide ETag");
-                String localETag = localResources.get(localName).getETag(),
-                        remoteETag = getETag.eTag;
-                if (remoteETag.equals(localETag))
-                    syncResult.stats.numSkippedEntries++;
-                else {
-                    App.log.info(localName + " has been changed on server (current ETag=" + remoteETag + ", last known ETag=" + localETag + ")");
-                    toDownload.add(remote);
-                }
-
-                // remote entry has been seen, remove from list
-                remoteResources.remove(localName);
-            }
-        }
-
-        // add all unseen (= remotely added) remote contacts
-        if (!remoteResources.isEmpty()) {
-            App.log.info("New resources have been found on the server: " + TextUtils.join(", ", remoteResources.keySet()));
-            toDownload.addAll(remoteResources.values());
-        }
-    }
-
-    /**
-     * Downloads the remote resources in {@link #toDownload} and stores them locally.
-     * Must check Thread.interrupted() periodically to allow quick sync cancellation.
-     */
-    abstract protected void downloadRemote() throws IOException, HttpException, DavException, ContactsStorageException, CalendarStorageException;
-
-    protected void saveSyncState() throws CalendarStorageException, ContactsStorageException {
-        /* Save sync state (CTag). It doesn't matter if it has changed during the sync process
-           (for instance, because another client has uploaded changes), because this will simply
-           cause all remote entries to be listed at the next sync. */
-        App.log.info("Saving CTag=" + remoteCTag);
-        localCollection.setCTag(remoteCTag);
-    }
-
-}