Fix crash because of empty drawable in -ose version

This reverts commit bcd7700dc7d2d67a6c3a25c8f9a18694e496a29c.

.gitlab-ci.yml

@@ -0,0 +1,31 @@
+image: registry.gitlab.com/bitfireat/docker-android-emulator:latest
+
+before_script:
+  - git submodule update --init --recursive
+  - export GRADLE_USER_HOME=`pwd`/.gradle; chmod +x gradlew
+
+cache:
+  paths:
+     - .gradle/
+
+test:
+  tags:
+    - privileged
+  script:
+   - start-emulator.sh
+   - ./gradlew app:check app:connectedCheck
+  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 +1,9 @@
-[submodule "dav4android"]
-	path = dav4android
-	url = https://gitlab.com/bitfireAT/dav4android.git
 [submodule "ical4android"]
 	path = ical4android
 	url = https://gitlab.com/bitfireAT/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
+[submodule "cert4android"]
+	path = cert4android
+	url = https://gitlab.com/bitfireAT/cert4android.git

CONTRIBUTING.md

@@ -0,0 +1,47 @@
+
+Contributing to DAVx⁵
+=====================
+
+**Thank you for your interest in contributing to DAVx⁵!**
+
+Because you're reading this, you're probably interested in
+contributing to the DAVx⁵ code. [Other ways to contribute:
+see here.](https://www.davx5.com/donate#c306)
+
+To contribute:
+
+1. It's good idea to have a look at the [DAVx⁵ Roadmap](https://gitlab.com/bitfireAT/davx5-ose/wikis/Roadmap)
+   to see whether the change is already planned. Maybe there's even a link to a
+   corresponding forum thread there.
+1. Determine which project the changes shall go to. There's
+   the DAVx⁵ main project (this repo), and the [related
+   libraries](README.md).
+1. Please post to the [DAVx⁵ development forum](https://www.davx5.com/forums)
+   before doing actual work (unless you do it only for yourself, of course).
+   This will help to coordinate activities and you'll also get hints
+   about where to start and possible pitfalls.
+1. Fork the repository.
+1. Do the changes in your repository.
+1. Submit a pull request to the original project.
+1. Post in the forum again (to make sure the pull request is being notified).
+
+
+Questions, discussion
+=====================
+
+We're happy to see questions, discussions etc. in the
+[DAVx⁵ development forum](https://www.davx5.com/forums)!
+
+
+Licensing
+=========
+
+All code has to be licensed under the GPL.
+
+We (bitfire.at, initial developers) are also asking you to double-license the
+code so that we can also use it for related non-open source projects like
+[Managed DAVx⁵](https://www.davx5.com/organizations/managed-davx5).
+
+Please find more about this in the Contributor's License Agreement (CLA)
+we'll send to you if you want to contribute.
+

README.md

@@ -1,34 +1,37 @@
+![DAVx⁵ logo](app/src/main/res/mipmap-xxxhdpi/ic_launcher.png)
 
-DAVdroid
+DAVx⁵
 ========
 
-Please see the [DAVdroid Web site](https://davdroid.bitfire.at) for
-comprehensive information about DAVdroid.
+Please see the [DAVx⁵ Web site](https://www.davx5.com) for
+comprehensive information about DAVx⁵.
 
-DAVdroid is licensed under the [GPLv3 License](LICENSE).
+DAVx⁵ is licensed under the [GPLv3 License](LICENSE).
 
-News and updates: [@davdroidapp](https://twitter.com/davdroidapp)
+News and updates: [@davx5app](https://twitter.com/davx5app) on Twitter
 
-Help and discussion: [DAVdroid forums](https://davdroid.bitfire.at/forums)
+Help, discussion, feature requests, bug reports and "issues": [DAVx⁵ forums](https://www.davx5.com/forums)
 
-Parts of DAVdroid have been outsourced into these libraries:
+**If you want to support DAVx⁵, please consider [donating to DAVx⁵](https://www.davx5.com/donate)
+or [purchasing it](https://www.davx5.com/download).**
 
-* [dav4android](https://gitlab.com/bitfireAT/dav4android) – WebDAV/CalDav/CardDAV framework
+Generated KDoc: https://bitfireAT.gitlab.io/davx5-ose/dokka/app/
+
+Parts of DAVx⁵ have been outsourced into these libraries:
+
+* [cert4android](https://gitlab.com/bitfireAT/cert4android) – custom certificate management
+* [dav4jvm](https://gitlab.com/bitfireAT/dav4jvm) – 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)
+* [vcard4android](https://gitlab.com/bitfireAT/vcard4android) – vCard processing and Contacts Provider access
 
 
 USED THIRD-PARTY LIBRARIES
 ==========================
 
-Those libraries are used by DAVdroid (alphabetically):
+Those libraries are used by DAVx⁵ (alphabetically):
 
+* [Color Picker](https://github.com/jaredrummler/ColorPicker) – [Apache License, Version 2.0](https://github.com/jaredrummler/ColorPicker/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)
-* [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)
+* [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)

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
@@ -7,27 +7,44 @@
  */
 
 apply plugin: 'com.android.application'
+apply plugin: 'com.mikepenz.aboutlibraries.plugin'
+apply plugin: 'kotlin-android'
+apply plugin: 'kotlin-android-extensions'
+apply plugin: 'kotlin-kapt'
+apply plugin: 'org.jetbrains.dokka'
 
 android {
-    compileSdkVersion 23
-    buildToolsVersion "23.0.3"
+    compileSdkVersion 29
+    buildToolsVersion '29.0.2'
 
     defaultConfig {
         applicationId "at.bitfire.davdroid"
-        minSdkVersion 14
-        targetSdkVersion 23
-
-        versionCode 109
 
+        versionCode 300000004
         buildConfigField "long", "buildTime", System.currentTimeMillis() + "L"
+        buildConfigField "boolean", "customCerts", "true"
+
+        minSdkVersion 21        // Android 5.0
+        targetSdkVersion 29     // Android 10.0
+
+        buildConfigField "String", "okhttpVersion", "\"${versions.okhttp}\""
+        buildConfigField "String", "userAgent", "\"DAVx5\""
     }
 
+    compileOptions {
+        sourceCompatibility JavaVersion.VERSION_1_8
+        targetCompatibility JavaVersion.VERSION_1_8
+    }
+    kotlinOptions {
+        jvmTarget = "1.8"
+    }
+
+    dataBinding.enabled = true
+
+    flavorDimensions "distribution"
     productFlavors {
         standard {
-            versionName "1.2"
-        }
-        gplay {
-            versionName "1.2-gplay"
+            versionName "3.0-ose2"
         }
     }
 
@@ -43,46 +60,92 @@ android {
 
     lintOptions {
         disable 'GoogleAppIndexingWarning'      // we don't need Google indexing, thanks
-        disable 'GradleDependency'
-        disable 'GradleDynamicVersion'
-        disable 'IconColors'
-        disable 'IconLauncherShape'
-        disable 'IconMissingDensityFolder'
-        disable 'ImpliedQuantity'
-        disable 'MissingTranslation'
-        disable 'MissingQuantity'
-        disable 'Recycle'           // doesn't understand Lombok's @Cleanup
+        disable 'ImpliedQuantity', 'MissingQuantity'		// quantities from Transifex may vary
+        disable 'MissingTranslation', 'ExtraTranslation'	// translations from Transifex are not always up to date
         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 "androidx.test.runner.AndroidJUnitRunner"
+    }
+
+    dokka.configuration {
+        sourceLink {
+            url = "https://gitlab.com/bitfireAT/davx5-ose/tree/master-ose/"
+            lineSuffix = "#L"
+        }
+        jdkVersion = 7
+
+        externalDocumentationLink {
+            url = new URL("https://bitfireat.gitlab.io/cert4android/dokka/cert4android/")
+            packageListUrl = new URL("https://bitfireat.gitlab.io/cert4android/dokka/cert4android/package-list")
+        }
+        externalDocumentationLink {
+            url = new URL("https://bitfireat.gitlab.io/dav4jvm/dokka/dav4jvm/")
+            packageListUrl = new URL("https://bitfireat.gitlab.io/dav4jvm/dokka/dav4jvm/package-list")
+        }
+        externalDocumentationLink {
+            url = new URL("https://bitfireat.gitlab.io/ical4android/dokka/ical4android/")
+            packageListUrl = new URL("https://bitfireat.gitlab.io/ical4android/dokka/ical4android/package-list")
+        }
+        externalDocumentationLink {
+            url = new URL("https://bitfireat.gitlab.io/vcard4android/dokka/vcard4android/")
+            packageListUrl = new URL("https://bitfireat.gitlab.io/vcard4android/dokka/vcard4android/package-list")
+        }
     }
 }
 
 dependencies {
-    compile project(':dav4android')
-    compile project(':ical4android')
-    compile project(':vcard4android')
+    implementation project(':cert4android')
+    implementation project(':ical4android')
+    implementation 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-v14:23.+'
+    implementation "org.jetbrains.kotlin:kotlin-stdlib-jdk8:${versions.kotlin}"
 
-    compile 'com.github.yukuku:ambilwarna:2.0.1'
-    compile project(':MemorizingTrustManager')
+    implementation 'androidx.appcompat:appcompat:1.2.0-beta01'
+    implementation 'androidx.cardview:cardview:1.0.0'
+    implementation 'androidx.constraintlayout:constraintlayout:2.0.0-beta4'
+    implementation 'androidx.fragment:fragment-ktx:1.2.4'
+    implementation 'androidx.lifecycle:lifecycle-extensions:2.2.0'
+    implementation 'androidx.lifecycle:lifecycle-viewmodel-ktx:2.2.0'
+    implementation 'androidx.paging:paging-runtime-ktx:2.1.2'
+    implementation 'androidx.preference:preference:1.1.1'
+    implementation 'androidx.swiperefreshlayout:swiperefreshlayout:1.1.0-rc01'
+    implementation 'com.google.android:flexbox:1.1.0'
+    implementation 'com.google.android.material:material:1.2.0-alpha06'
 
-    compile 'dnsjava:dnsjava:2.1.7'
-    compile 'org.apache.commons:commons-lang3:3.4'
-    compile 'org.apache.commons:commons-collections4:4.1'
-    provided 'org.projectlombok:lombok:1.16.8'
+    def room_version = '2.2.5'
+    implementation "androidx.room:room-runtime:$room_version"
+    implementation "androidx.room:room-ktx:$room_version"
+    kapt "androidx.room:room-compiler:$room_version"
+
+    implementation 'com.jaredrummler:colorpicker:1.1.0'
+    implementation "com.github.AppIntro:AppIntro:${versions.appIntro}"
+    implementation "com.gitlab.bitfireAT:dav4jvm:${versions.dav4jvm}"
+    implementation "com.mikepenz:aboutlibraries:${versions.aboutLibraries}"
+    implementation "com.squareup.okhttp3:okhttp:${versions.okhttp}"
+    implementation "com.squareup.okhttp3:okhttp-brotli:${versions.okhttp}"
+    implementation "com.squareup.okhttp3:logging-interceptor:${versions.okhttp}"
+    implementation 'commons-io:commons-io:2.6'
+    //noinspection GradleDependency - dnsjava 3+ needs Java 8/Android 7
+    implementation 'dnsjava:dnsjava:2.1.9'
+    implementation 'org.apache.commons:commons-collections4:4.4'
+    //noinspection GradleDependency - commons-lang 3.10+ needs Java 8/Android 7
+    implementation 'org.apache.commons:commons-lang3:3.9'
+    implementation 'org.apache.commons:commons-text:1.8'
 
     // for tests
-    testCompile 'junit:junit:4.12'
-    testCompile 'com.squareup.okhttp3:mockwebserver:3.3.1'
-    androidTestCompile 'com.squareup.okhttp3:mockwebserver:3.3.1'
+    androidTestImplementation 'androidx.test:runner:1.2.0'
+    androidTestImplementation 'androidx.test:rules:1.2.0'
+    androidTestImplementation 'junit:junit:4.13'
+    androidTestImplementation "com.squareup.okhttp3:mockwebserver:${versions.okhttp}"
+
+    testImplementation 'junit:junit:4.13'
+    testImplementation "com.squareup.okhttp3:mockwebserver:${versions.okhttp}"
 }

app/proguard-rules.txt

@@ -1,9 +1,9 @@
 
-# ProGuard usage for DAVdroid:
-# 	shrinking		yes (main reason for using ProGuard)
-# 	optimization		yes
-# 	obfuscation		no (DAVdroid is open-source)
-# 	preverification		no
+# ProGuard usage for DAVx⁵:
+#       shrinking        yes (main reason for using ProGuard)
+#       optimization     yes
+#       obfuscation      no (DAVx⁵ is open-source)
+#       preverification  no
 
 -dontobfuscate
 
@@ -13,29 +13,29 @@
 -dontpreverify
 
 # ez-vcard
--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
--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)
-
-# okhttp
--dontwarn java.nio.file.**		# not available on Android
--dontwarn org.codehaus.mojo.animal_sniffer.IgnoreJRERequirement
-
-# MemorizingTrustManager
--dontwarn de.duenndns.ssl.MemorizingTrustManager
+-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)
 
 # 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
+# DAVx⁵ + libs
+-keep class at.bitfire.** { *; }       # all DAVx⁵ code is required
+
+# we use enum classes (https://www.guardsquare.com/en/products/proguard/manual/examples#enumerations)
+-keepclassmembers,allowoptimization enum * {
+    public static **[] values();
+    public static ** valueOf(java.lang.String);
+}

app/src/.gitignore

@@ -0,0 +1 @@
+espressoTest

app/src/androidTest/java/at/bitfire/davdroid/HttpClientTest.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
+
+import okhttp3.Request
+import okhttp3.mockwebserver.MockResponse
+import okhttp3.mockwebserver.MockWebServer
+import org.junit.After
+import org.junit.Assert.assertEquals
+import org.junit.Assert.assertNull
+import org.junit.Before
+import org.junit.Test
+
+class HttpClientTest {
+
+    lateinit var server: MockWebServer
+    lateinit var httpClient: HttpClient
+
+    @Before
+    fun setUp() {
+        httpClient = HttpClient.Builder().build()
+
+        server = MockWebServer()
+        server.start(30000)
+    }
+
+    @After
+    fun tearDown() {
+        server.shutdown()
+        httpClient.close()
+    }
+
+
+    @Test
+    fun testCookies() {
+        val url = server.url("/test")
+
+        // set cookie for root path (/) and /test path in first response
+        server.enqueue(MockResponse()
+                .setResponseCode(200)
+                .addHeader("Set-Cookie", "cookie1=1; path=/")
+                .addHeader("Set-Cookie", "cookie2=2")
+                .setBody("Cookie set"))
+        httpClient.okHttpClient.newCall(Request.Builder()
+                .get().url(url)
+                .build()).execute()
+        assertNull(server.takeRequest().getHeader("Cookie"))
+
+        // cookie should be sent with second request
+        // second response lets first cookie expire and overwrites second cookie
+        server.enqueue(MockResponse()
+                .addHeader("Set-Cookie", "cookie1=1a; path=/; Max-Age=0")
+                .addHeader("Set-Cookie", "cookie2=2a")
+                .setResponseCode(200))
+        httpClient.okHttpClient.newCall(Request.Builder()
+                .get().url(url)
+                .build()).execute()
+        assertEquals("cookie2=2; cookie1=1", server.takeRequest().getHeader("Cookie"))
+
+        server.enqueue(MockResponse()
+                .setResponseCode(200))
+        httpClient.okHttpClient.newCall(Request.Builder()
+                .get().url(url)
+                .build()).execute()
+        assertEquals("cookie2=2a", server.takeRequest().getHeader("Cookie"))
+    }
+
+}

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

@@ -1,53 +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 java.io.IOException;
-import java.net.Socket;
-
-import javax.net.ssl.SSLSocket;
-
-import de.duenndns.ssl.MemorizingTrustManager;
-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/model/CollectionInfoTest.java

@@ -1,110 +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 junit.framework.TestCase;
-
-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;
-
-public class CollectionInfoTest extends TestCase {
-
-    MockWebServer server = new MockWebServer();
-
-    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.create(), server.url("/"));
-        dav.propfind(0, ResourceType.NAME);
-        CollectionInfo info = CollectionInfo.fromDavResource(dav);
-        assertEquals(CollectionInfo.Type.ADDRESS_BOOK, info.type);
-        assertFalse(info.readOnly);
-        assertEquals("My Contacts", info.displayName);
-        assertEquals("My Contacts Description", info.description);
-
-        // 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.create(), server.url("/"));
-        dav.propfind(0, ResourceType.NAME);
-        info = CollectionInfo.fromDavResource(dav);
-        assertEquals(CollectionInfo.Type.CALENDAR, info.type);
-        assertTrue(info.readOnly);
-        assertNull(info.displayName);
-        assertEquals("My Calendar", info.description);
-        assertEquals(0xFFFF0000, (int)info.color);
-        assertEquals("tzdata", info.timeZone);
-        assertTrue(info.supportsVEVENT);
-        assertTrue(info.supportsVTODO);
-    }
-
-    public void testFromDB() {
-        ContentValues values = new ContentValues();
-        values.put(Collections.ID, 1);
-        values.put(Collections.SERVICE_ID, 1);
-        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 = CollectionInfo.fromDB(values);
-        assertEquals(1, info.id);
-        assertEquals(1, (long)info.serviceID);
-        assertEquals("http://example.com", info.url);
-        assertTrue(info.readOnly);
-        assertEquals("display name", info.displayName);
-        assertEquals("description", info.description);
-        assertEquals(0xFFFF0000, (int)info.color);
-        assertEquals("tzdata", info.timeZone);
-        assertTrue(info.supportsVEVENT);
-        assertTrue(info.supportsVTODO);
-        assertTrue(info.selected);
-    }
-
-}

app/src/androidTest/java/at/bitfire/davdroid/model/CollectionTest.kt

@@ -0,0 +1,134 @@
+/*
+ * 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 androidx.test.filters.SmallTest
+import at.bitfire.dav4jvm.DavResource
+import at.bitfire.dav4jvm.property.ResourceType
+import at.bitfire.davdroid.HttpClient
+import okhttp3.HttpUrl.Companion.toHttpUrl
+import okhttp3.mockwebserver.MockResponse
+import okhttp3.mockwebserver.MockWebServer
+import org.junit.After
+import org.junit.Assert.*
+import org.junit.Before
+import org.junit.Test
+
+class CollectionTest {
+
+    private lateinit var httpClient: HttpClient
+    private val server = MockWebServer()
+
+    @Before
+    fun setUp() {
+        httpClient = HttpClient.Builder().build()
+    }
+
+    @After
+    fun shutDown() {
+        httpClient.close()
+    }
+
+
+    @Test
+    @SmallTest
+    fun testFromDavResponseAddressBook() {
+        // r/w address book
+        server.enqueue(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>"))
+
+        lateinit var info: Collection
+        DavResource(httpClient.okHttpClient, server.url("/"))
+                .propfind(0, ResourceType.NAME) { response, _ ->
+            info = Collection.fromDavResponse(response) ?: throw IllegalArgumentException()
+        }
+        assertEquals(Collection.TYPE_ADDRESSBOOK, info.type)
+        assertTrue(info.privWriteContent)
+        assertTrue(info.privUnbind)
+        assertNull(info.supportsVEVENT)
+        assertNull(info.supportsVTODO)
+        assertNull(info.supportsVJOURNAL)
+        assertEquals("My Contacts", info.displayName)
+        assertEquals("My Contacts Description", info.description)
+    }
+
+    @Test
+    @SmallTest
+    fun testFromDavResponseCalendar() {
+        // read-only calendar, no display name
+        server.enqueue(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>"))
+
+        lateinit var info: Collection
+        DavResource(httpClient.okHttpClient, server.url("/"))
+                .propfind(0, ResourceType.NAME) { response, _ ->
+                    info = Collection.fromDavResponse(response) ?: throw IllegalArgumentException()
+                }
+        assertEquals(Collection.TYPE_CALENDAR, info.type)
+        assertFalse(info.privWriteContent)
+        assertFalse(info.privUnbind)
+        assertNull(info.displayName)
+        assertEquals("My Calendar", info.description)
+        assertEquals(0xFFFF0000.toInt(), info.color)
+        assertEquals("tzdata", info.timezone)
+        assertTrue(info.supportsVEVENT!!)
+        assertTrue(info.supportsVTODO!!)
+        assertTrue(info.supportsVJOURNAL!!)
+    }
+
+    @Test
+    @SmallTest
+    fun testFromDavResponseWebcal() {
+        // Webcal subscription
+        server.enqueue(MockResponse()
+                .setResponseCode(207)
+                .setBody("<multistatus xmlns='DAV:' xmlns:CS='http://calendarserver.org/ns/'>" +
+                        "<response>" +
+                        "   <href>/webcal1</href>" +
+                        "   <propstat><prop>" +
+                        "       <displayname>Sample Subscription</displayname>" +
+                        "       <resourcetype><collection/><CS:subscribed/></resourcetype>" +
+                        "       <CS:source><href>webcals://example.com/1.ics</href></CS:source>" +
+                        "   </prop></propstat>" +
+                        "</response>" +
+                        "</multistatus>"))
+
+        lateinit var info: Collection
+        DavResource(httpClient.okHttpClient, server.url("/"))
+                .propfind(0, ResourceType.NAME) { response, _ ->
+                    info = Collection.fromDavResponse(response) ?: throw IllegalArgumentException()
+                }
+        assertEquals(Collection.TYPE_WEBCAL, info.type)
+        assertEquals("Sample Subscription", info.displayName)
+        assertEquals("https://example.com/1.ics".toHttpUrl(), info.source)
+    }
+
+}

app/src/androidTest/java/at/bitfire/davdroid/model/DaoToolsTest.kt

@@ -0,0 +1,64 @@
+package at.bitfire.davdroid.model
+
+import androidx.room.Room
+import androidx.test.platform.app.InstrumentationRegistry
+import okhttp3.HttpUrl
+import okhttp3.HttpUrl.Companion.toHttpUrl
+import org.junit.After
+import org.junit.Assert.*
+import org.junit.Before
+import org.junit.Test
+
+class DaoToolsTest {
+
+    private lateinit var db: AppDatabase
+
+    @Before
+    fun createDb() {
+        val context = InstrumentationRegistry.getInstrumentation().context
+        db = Room.inMemoryDatabaseBuilder(context, AppDatabase::class.java).build()
+    }
+
+    @After
+    fun closeDb() {
+        db.close()
+    }
+
+    @Test
+    fun testSyncAll() {
+        val serviceDao = db.serviceDao()
+        val service = Service(id=0, accountName="test", type=Service.TYPE_CALDAV, principal = null)
+        service.id = serviceDao.insertOrReplace(service)
+
+        val homeSetDao = db.homeSetDao()
+        val entry1 = HomeSet(id=1, serviceId=service.id, url= "https://example.com/1".toHttpUrl())
+        val entry3 = HomeSet(id=3, serviceId=service.id, url= "https://example.com/3".toHttpUrl())
+        val oldItems = listOf(
+                entry1,
+                HomeSet(id=2, serviceId=service.id, url= "https://example.com/2".toHttpUrl()),
+                entry3
+        )
+        homeSetDao.insert(oldItems)
+
+        val newItems = mutableMapOf<HttpUrl, HomeSet>()
+        newItems[entry1.url] = entry1
+
+        // no id, because identity is given by the url
+        val updated = HomeSet(id=0, serviceId=service.id,
+                url= "https://example.com/2".toHttpUrl(), displayName="Updated Entry")
+        newItems[updated.url] = updated
+
+        val created = HomeSet(id=4, serviceId=service.id, url= "https://example.com/4".toHttpUrl())
+        newItems[created.url] = created
+
+        DaoTools(homeSetDao).syncAll(oldItems, newItems, { it.url })
+
+        val afterSync = homeSetDao.getByService(service.id)
+        assertEquals(afterSync.size, 3)
+        assertFalse(afterSync.contains(entry3))
+        assertTrue(afterSync.contains(entry1))
+        assertTrue(afterSync.contains(updated))
+        assertTrue(afterSync.contains(created))
+    }
+
+}

app/src/androidTest/java/at/bitfire/davdroid/settings/DefaultsSettingsProviderTest.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 org.junit.Assert.assertEquals
+import org.junit.Assert.assertFalse
+import org.junit.Test
+
+class DefaultsSettingsProviderTest {
+
+    private val provider: SettingsProvider = DefaultsProvider()
+
+    @Test
+    fun testHas() {
+        assertEquals(Pair(false, true), provider.has("notExisting"))
+        assertEquals(Pair(true, true), provider.has(Settings.OVERRIDE_PROXY))
+    }
+
+    @Test
+    fun testGet() {
+        assertEquals(Pair("localhost", true), provider.getString(Settings.OVERRIDE_PROXY_HOST))
+        assertEquals(Pair(8118, true), provider.getInt(Settings.OVERRIDE_PROXY_PORT))
+    }
+
+    @Test
+    fun testPutRemove() {
+        assertEquals(Pair(false, true), provider.isWritable(Settings.OVERRIDE_PROXY))
+        assertFalse(provider.putBoolean(Settings.OVERRIDE_PROXY, true))
+        assertFalse(provider.remove(Settings.OVERRIDE_PROXY))
+    }
+
+}

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

@@ -0,0 +1,34 @@
+/*
+ * 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 androidx.test.platform.app.InstrumentationRegistry
+import org.junit.Assert.assertFalse
+import org.junit.Assert.assertTrue
+import org.junit.Before
+import org.junit.Test
+
+class SettingsTest {
+
+    lateinit var settings: Settings
+
+    @Before
+    fun initialize() {
+        settings = Settings.getInstance(InstrumentationRegistry.getInstrumentation().targetContext)
+    }
+
+    @Test
+    fun testHas() {
+        assertFalse(settings.has("notExisting"))
+
+        // provided by DefaultsProvider
+        assertTrue(settings.has(Settings.OVERRIDE_PROXY))
+    }
+
+}

app/src/androidTest/java/at/bitfire/davdroid/syncadapter/SyncAdapterServiceTest.kt

@@ -0,0 +1,31 @@
+package at.bitfire.davdroid.syncadapter
+
+import android.os.Bundle
+import androidx.test.filters.SmallTest
+import at.bitfire.davdroid.syncadapter.SyncAdapterService.SyncAdapter
+import org.junit.Assert.assertArrayEquals
+import org.junit.Assert.assertTrue
+import org.junit.Test
+
+class SyncAdapterServiceTest {
+
+    @Test
+    @SmallTest
+    fun testPriorityCollections() {
+        val extras = Bundle()
+        assertTrue(SyncAdapter.priorityCollections(extras).isEmpty())
+
+        extras.putString(SyncAdapterService.SYNC_EXTRAS_PRIORITY_COLLECTIONS, "")
+        assertTrue(SyncAdapter.priorityCollections(extras).isEmpty())
+
+        extras.putString(SyncAdapterService.SYNC_EXTRAS_PRIORITY_COLLECTIONS, "123")
+        assertArrayEquals(longArrayOf(123), SyncAdapter.priorityCollections(extras).toLongArray())
+
+        extras.putString(SyncAdapterService.SYNC_EXTRAS_PRIORITY_COLLECTIONS, ",x,")
+        assertTrue(SyncAdapter.priorityCollections(extras).isEmpty())
+
+        extras.putString(SyncAdapterService.SYNC_EXTRAS_PRIORITY_COLLECTIONS, "1,2,3")
+        assertArrayEquals(longArrayOf(1,2,3), SyncAdapter.priorityCollections(extras).toLongArray())
+    }
+
+}

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

@@ -1,189 +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.ui.setup;
-
-import android.test.InstrumentationTestCase;
-
-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.App;
-import at.bitfire.davdroid.HttpClient;
-import at.bitfire.davdroid.ui.setup.DavResourceFinder;
-import at.bitfire.davdroid.ui.setup.DavResourceFinder.Configuration.ServiceInfo;
-import at.bitfire.davdroid.ui.setup.LoginCredentials;
-import okhttp3.OkHttpClient;
-import okhttp3.mockwebserver.Dispatcher;
-import okhttp3.mockwebserver.MockResponse;
-import okhttp3.mockwebserver.MockWebServer;
-import okhttp3.mockwebserver.RecordedRequest;
-
-public class DavResourceFinderTest extends InstrumentationTestCase {
-
-    MockWebServer server = new MockWebServer();
-
-    DavResourceFinder finder;
-    OkHttpClient client;
-    LoginCredentials credentials;
-
-    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";
-
-    @Override
-    protected void setUp() throws Exception {
-        server.setDispatcher(new TestDispatcher());
-        server.start();
-
-        credentials = new LoginCredentials(URI.create("/"), "mock", "12345", true);
-        finder = new DavResourceFinder(getInstrumentation().getContext(), credentials);
-
-        client = HttpClient.create();
-        client = HttpClient.addAuthentication(client, credentials.userName, credentials.password, credentials.authPreemptive);
-    }
-
-    @Override
-    protected void tearDown() throws Exception {
-        server.shutdown();
-    }
-
-
-    public void testRememberIfAddressBookOrHomeset() throws IOException, HttpException, DavException {
-        ServiceInfo info;
-
-        // before dav.propfind(), no info is available
-        DavResource dav = new DavResource(client, server.url(PATH_CARDDAV + SUBPATH_PRINCIPAL));
-        finder.rememberIfAddressBookOrHomeset(dav, info = new ServiceInfo());
-        assertEquals(0, info.collections.size());
-        assertEquals(0, info.homeSets.size());
-
-        // recognize home set
-        dav.propfind(0, AddressbookHomeSet.NAME);
-        finder.rememberIfAddressBookOrHomeset(dav, info = new ServiceInfo());
-        assertEquals(0, info.collections.size());
-        assertEquals(1, info.homeSets.size());
-        assertEquals(server.url(PATH_CARDDAV + SUBPATH_ADDRESSBOOK_HOMESET + "/").uri(), info.homeSets.iterator().next());
-
-        // recognize address book
-        dav = new DavResource(client, server.url(PATH_CARDDAV + SUBPATH_ADDRESSBOOK));
-        dav.propfind(0, ResourceType.NAME);
-        finder.rememberIfAddressBookOrHomeset(dav, info = new ServiceInfo());
-        assertEquals(1, info.collections.size());
-        assertEquals(server.url(PATH_CARDDAV + SUBPATH_ADDRESSBOOK + "/").uri(), info.collections.keySet().iterator().next());
-        assertEquals(0, info.homeSets.size());
-    }
-
-    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));
-    }
-
-    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))
-                return new MockResponse().setResponseCode(401);
-
-            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;
-                }
-                App.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/java/at/bitfire/davdroid/ui/setup/DavResourceFinderTest.kt

@@ -0,0 +1,191 @@
+/*
+ * 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 androidx.test.filters.SmallTest
+import androidx.test.platform.app.InstrumentationRegistry
+import at.bitfire.dav4jvm.DavResource
+import at.bitfire.dav4jvm.property.AddressbookHomeSet
+import at.bitfire.dav4jvm.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 org.junit.After
+import org.junit.Assert.*
+import org.junit.Before
+import org.junit.Test
+import java.net.URI
+
+class DavResourceFinderTest {
+
+    companion object {
+        private const val PATH_NO_DAV = "/nodav"
+        private const val PATH_CALDAV = "/caldav"
+        private const val PATH_CARDDAV = "/carddav"
+        private const val PATH_CALDAV_AND_CARDDAV = "/both-caldav-carddav"
+
+        private const val SUBPATH_PRINCIPAL = "/principal"
+        private const val SUBPATH_ADDRESSBOOK_HOMESET = "/addressbooks"
+        private const val SUBPATH_ADDRESSBOOK = "/addressbooks/private-contacts"
+    }
+
+    val server = MockWebServer()
+
+    lateinit var finder: DavResourceFinder
+    lateinit var client: HttpClient
+    lateinit var loginModel: LoginModel
+
+    @Before
+    fun initServerAndClient() {
+        server.dispatcher = TestDispatcher()
+        server.start()
+
+        loginModel = LoginModel()
+        loginModel.baseURI = URI.create("/")
+        loginModel.credentials = Credentials("mock", "12345")
+
+        finder = DavResourceFinder(InstrumentationRegistry.getInstrumentation().targetContext, loginModel)
+        client = HttpClient.Builder()
+                .addAuthentication(null, loginModel.credentials!!)
+                .build()
+    }
+
+    @After
+    fun stopServer() {
+        server.shutdown()
+    }
+
+
+    @Test
+    @SmallTest
+    fun testRememberIfAddressBookOrHomeset() {
+        // recognize home set
+        var info = ServiceInfo()
+        DavResource(client.okHttpClient, server.url(PATH_CARDDAV + SUBPATH_PRINCIPAL))
+                .propfind(0, AddressbookHomeSet.NAME) { response, _ ->
+            finder.scanCardDavResponse(response, info)
+        }
+        assertEquals(0, info.collections.size)
+        assertEquals(1, info.homeSets.size)
+        assertEquals(server.url("$PATH_CARDDAV$SUBPATH_ADDRESSBOOK_HOMESET/"), info.homeSets.first())
+
+        // recognize address book
+        info = ServiceInfo()
+        DavResource(client.okHttpClient, server.url(PATH_CARDDAV + SUBPATH_ADDRESSBOOK))
+                .propfind(0, ResourceType.NAME) { response, _ ->
+            finder.scanCardDavResponse(response, info)
+        }
+        assertEquals(1, info.collections.size)
+        assertEquals(server.url("$PATH_CARDDAV$SUBPATH_ADDRESSBOOK/"), info.collections.keys.first())
+        assertEquals(0, info.homeSets.size)
+    }
+
+    @Test
+    fun testProvidesService() {
+        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
+    fun testGetCurrentUserPrincipal() {
+        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),
+                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),
+                finder.getCurrentUserPrincipal(server.url(PATH_CARDDAV), DavResourceFinder.Service.CARDDAV)
+        )
+        assertNull(finder.getCurrentUserPrincipal(server.url(PATH_CARDDAV), DavResourceFinder.Service.CALDAV))
+    }
+
+
+    // mock server
+
+    class TestDispatcher: Dispatcher() {
+
+        override fun dispatch(request: RecordedRequest): MockResponse {
+            if (!checkAuth(request)) {
+                val authenticate = MockResponse().setResponseCode(401)
+                authenticate.setHeader("WWW-Authenticate", "Basic realm=\"test\"")
+                return authenticate
+            }
+
+            val path = request.path!!
+
+            if (request.method.equals("OPTIONS", true)) {
+                val dav = when {
+                    path.startsWith(PATH_CALDAV) -> "calendar-access"
+                    path.startsWith(PATH_CARDDAV) -> "addressbook"
+                    path.startsWith(PATH_CALDAV_AND_CARDDAV) -> "calendar-access, addressbook"
+                    else -> null
+                }
+                val response = MockResponse().setResponseCode(200)
+                if (dav != null)
+                    response.addHeader("DAV", dav)
+                return response
+            } else if (request.method.equals("PROPFIND", true)) {
+                val props: String?
+                when (path) {
+                    PATH_CALDAV,
+                    PATH_CARDDAV ->
+                        props = "<current-user-principal><href>$path$SUBPATH_PRINCIPAL</href></current-user-principal>"
+
+                    PATH_CARDDAV + SUBPATH_PRINCIPAL ->
+                        props = "<CARD:addressbook-home-set>" +
+                                "   <href>$PATH_CARDDAV$SUBPATH_ADDRESSBOOK_HOMESET</href>" +
+                                "</CARD:addressbook-home-set>"
+
+                    PATH_CARDDAV + SUBPATH_ADDRESSBOOK ->
+                        props = "<resourcetype>" +
+                                "   <collection/>" +
+                                "   <CARD:addressbook/>" +
+                                "</resourcetype>"
+
+                    else -> props = null
+                }
+                Logger.log.info("Sending props: $props")
+                return MockResponse()
+                        .setResponseCode(207)
+                        .setBody("<multistatus xmlns='DAV:' xmlns:CARD='urn:ietf:params:xml:ns:carddav'>" +
+                                "<response>" +
+                                "   <href>${request.path}</href>" +
+                                "   <propstat><prop>$props</prop></propstat>" +
+                                "</response>" +
+                                "</multistatus>")
+            }
+
+            return MockResponse().setResponseCode(404)
+        }
+
+        private fun checkAuth(rq: RecordedRequest) =
+            rq.getHeader("Authorization") == "Basic bW9jazoxMjM0NQ=="
+
+    }
+
+}

app/src/gplay/res/menu/activity_accounts_drawer.xml

@@ -1,55 +0,0 @@
-<?xml version="1.0" encoding="utf-8"?>
-<!--
-  ~ 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
-  -->
-
-<menu xmlns:tools="http://schemas.android.com/tools"
-      xmlns:android="http://schemas.android.com/apk/res/android">
-
-    <item
-        android:id="@+id/nav_about"
-        android:icon="@drawable/ic_info_dark"
-        android:title="@string/navigation_drawer_about"/>
-    <item
-        android:id="@+id/nav_app_settings"
-        android:icon="@drawable/ic_settings_dark"
-        android:title="@string/navigation_drawer_settings"/>
-
-    <item android:title="@string/navigation_drawer_news_updates">
-        <menu>
-            <item
-                android:id="@+id/nav_twitter"
-                android:icon="@drawable/twitter"
-                android:title="\@davdroidapp"
-                tools:ignore="HardcodedText"/>
-        </menu>
-    </item>
-
-    <item android:title="@string/navigation_drawer_external_links">
-        <menu>
-            <item
-                android:id="@+id/nav_website"
-                android:icon="@drawable/ic_home_dark"
-                android:title="@string/navigation_drawer_website"/>
-            <item
-                android:id="@+id/nav_faq"
-                android:icon="@drawable/ic_help_dark"
-                android:title="@string/navigation_drawer_faq"/>
-            <item
-                android:id="@+id/nav_forums"
-                android:icon="@drawable/ic_forum_dark"
-                android:title="@string/navigation_drawer_forums"/>
-            <item
-                android:id="@+id/nav_donate"
-                android:icon="@drawable/ic_attach_money_dark"
-                android:title="(entry disabled)"
-                android:visible="false"
-                tools:ignore="HardcodedText"/>
-        </menu>
-    </item>
-
-</menu>

app/src/main/AndroidManifest.xml

@@ -1,11 +1,4 @@
 <?xml version="1.0" encoding="utf-8"?>
-<!--
-  ~ Copyright (c) 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
--->
 <manifest package="at.bitfire.davdroid"
           xmlns:android="http://schemas.android.com/apk/res/android"
           xmlns:tools="http://schemas.android.com/tools"
@@ -15,28 +8,15 @@
     <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"/>
 
-    <!-- legacy permissions -->
-    <uses-permission
-        android:name="android.permission.AUTHENTICATE_ACCOUNTS"
-        android:maxSdkVersion="22"
-        tools:ignore="UnusedAttribute"/>
-    <!--
-         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"/>
+    <!-- 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"/>
 
     <!-- other permissions -->
     <!-- android.permission-group.CONTACTS -->
@@ -46,101 +26,28 @@
     <uses-permission android:name="android.permission.READ_CALENDAR"/>
     <uses-permission android:name="android.permission.WRITE_CALENDAR"/>
 
+    <!-- android.permission-group.LOCATION -->
+    <!-- getting the WiFi name (for "sync in Wifi only") requires
+      - coarse location (Android 8.1)
+      - fine location (Android 10)  -->
+    <uses-permission-sdk-23 android:name="android.permission.ACCESS_FINE_LOCATION"/>
+    <!-- required since Android 10 to get the WiFi name while in background (= while syncing) -->
+    <uses-permission-sdk-23 android:name="android.permission.ACCESS_BACKGROUND_LOCATION"/>
+
     <!-- ical4android declares task access permissions -->
 
     <application
         android:name=".App"
-        android:allowBackup="true"
-        android:fullBackupContent="false"
-        android:icon="@drawable/ic_launcher"
+        android:allowBackup="false"
+        android:networkSecurityConfig="@xml/network_security_config"
+        android:icon="@mipmap/ic_launcher"
         android:label="@string/app_name"
         android:theme="@style/AppTheme"
         tools:ignore="UnusedAttribute">
 
-        <receiver
-            android:name=".App$ReinitLoggingReceiver"
-            android:exported="false"
-            android:process=":sync">
-            <intent-filter>
-                <action android:name="at.bitfire.davdroid.REINIT_LOGGER"/>
-            </intent-filter>
-        </receiver>
-        <receiver
-            android:name=".AccountSettings$AppUpdatedReceiver"
-            android:exported="true">
-            <intent-filter>
-                <action android:name="android.intent.action.PACKAGE_REPLACED" />
-                <data android:scheme="package" android:path="at.bitfire.davdroid" />
-            </intent-filter>
-        </receiver>
+        <service android:name=".DavService"/>
 
-        <service
-            android:name=".syncadapter.AccountAuthenticatorService"
-            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"/>
-        </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"
-            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_calendars"/>
-        </service>
-        <service
-            android:name=".syncadapter.TasksSyncAdapterService"
-            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_tasks"/>
-        </service>
-
-        <service
-            android:name=".DavService"
-            android:enabled="true">
-        </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.intro.IntroActivity" android:theme="@style/AppTheme.NoActionBar" />
         <activity
             android:name=".ui.AccountsActivity"
             android:label="@string/app_name"
@@ -153,18 +60,19 @@
 
         <activity
             android:name=".ui.AboutActivity"
-            android:label="@string/app_name"
+            android:label="@string/navigation_drawer_about"
             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"/>
+            android:parentActivityName=".ui.AccountsActivity"
+            android:exported="true">
+            <intent-filter>
+                <action android:name="android.intent.action.APPLICATION_PREFERENCES"/>
+            </intent-filter>
+        </activity>
 
         <activity
             android:name=".ui.setup.LoginActivity"
@@ -176,10 +84,10 @@
         </activity>
 
         <activity
-            android:name=".ui.AccountActivity"
-            android:parentActivityName=".ui.AccountsActivity">
-        </activity>
-        <activity android:name=".ui.AccountSettingsActivity"/>
+            android:name=".ui.account.AccountActivity"
+            android:parentActivityName=".ui.AccountsActivity"
+            android:theme="@style/AppTheme.NoActionBar"/>
+        <activity android:name=".ui.account.SettingsActivity"/>
         <activity android:name=".ui.CreateAddressBookActivity"
             android:label="@string/create_addressbook"/>
         <activity android:name=".ui.CreateCalendarActivity"
@@ -187,14 +95,105 @@
 
         <activity
             android:name=".ui.DebugInfoActivity"
+            android:parentActivityName=".ui.AppSettingsActivity"
             android:exported="true"
             android:label="@string/debug_info_title">
+            <intent-filter>
+                <action android:name="android.intent.action.BUG_REPORT"/>
+            </intent-filter>
         </activity>
+        <provider
+            android:name="androidx.core.content.FileProvider"
+            android:authorities="@string/authority_debug_provider"
+            android:grantUriPermissions="true"
+            android:exported="false">
+            <meta-data
+                android:name="android.support.FILE_PROVIDER_PATHS"
+                android:resource="@xml/debug_paths" />
+        </provider>
 
-        <!-- MemorizingTrustManager -->
-        <activity
-            android:name="de.duenndns.ssl.MemorizingActivity"
-            android:theme="@android:style/Theme.Holo.Light.Dialog.NoActionBar"/>
+        <!-- account type "DAVx⁵" -->
+        <service
+            android:name=".syncadapter.AccountAuthenticatorService"
+            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"/>
+        </service>
+        <service
+            android:name=".syncadapter.CalendarsSyncAdapterService"
+            android:exported="true"
+            tools:ignore="ExportedService">
+            <intent-filter>
+                <action android:name="android.content.SyncAdapter"/>
+            </intent-filter>
+
+            <meta-data
+                android:name="android.content.SyncAdapter"
+                android:resource="@xml/sync_calendars"/>
+        </service>
+        <service
+            android:name=".syncadapter.TasksSyncAdapterService"
+            android:exported="true"
+            tools:ignore="ExportedService">
+            <intent-filter>
+                <action android:name="android.content.SyncAdapter"/>
+            </intent-filter>
+
+            <meta-data
+                android:name="android.content.SyncAdapter"
+                android:resource="@xml/sync_tasks"/>
+        </service>
+
+        <!-- account type "DAVx⁵ Address book" -->
+        <service
+            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>
+        <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"
+            tools:ignore="ExportedService">
+            <intent-filter>
+                <action android:name="android.content.SyncAdapter"/>
+            </intent-filter>
+
+            <meta-data
+                android:name="android.content.SyncAdapter"
+                android:resource="@xml/sync_address_books"/>
+        </service>
+        <service
+            android:name=".syncadapter.ContactsSyncAdapterService"
+            android:exported="true"
+            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/assets/apache2.html

@@ -1,153 +0,0 @@
-<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
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-<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
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-<p>"Contribution" shall mean any work of authorship, including the original
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-<p><strong><a name="copyright">2. Grant of Copyright License</a></strong>. Subject to the
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-<p>a. You must give any other recipients of the Work or Derivative Works a
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-<p>b. You must cause any modified files to carry prominent notices stating
-that You changed the files; and</p>
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-at least one of the following places: within a NOTICE text file distributed
-as part of the Derivative Works; within the Source form or documentation,
-if provided along with the Derivative Works; or, within a display generated
-by the Derivative Works, if and wherever such third-party notices normally
-appear. The contents of the NOTICE file are for informational purposes only
-and do not modify the License. You may add Your own attribution notices
-within Derivative Works that You distribute, alongside or as an addendum to
-the NOTICE text from the Work, provided that such additional attribution
-notices cannot be construed as modifying the License.
-<br/>
-<br/>
-You may add Your own copyright statement to Your modifications and may
-provide additional or different license terms and conditions for use,
-reproduction, or distribution of Your modifications, or for any such
-Derivative Works as a whole, provided Your use, reproduction, and
-distribution of the Work otherwise complies with the conditions stated in
-this License.
-</p>
-
-<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

@@ -1,28 +0,0 @@
-<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

@@ -1,23 +0,0 @@
-<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/gplv3.html

@@ -2,9 +2,9 @@
 <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>
+&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>
 
@@ -42,16 +42,16 @@ know their rights.</p>
 (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
+<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
+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
@@ -77,7 +77,7 @@ modification follow.</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>
@@ -135,7 +135,7 @@ 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
+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
@@ -177,7 +177,7 @@ your copyrighted material outside their relationship with you.</p>
 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>
+<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
@@ -189,13 +189,13 @@ measures.</p>
 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
+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
+<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
@@ -240,7 +240,7 @@ 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
+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>
@@ -462,7 +462,7 @@ 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
+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>
@@ -479,9 +479,9 @@ sale, or importing the Program or any portion of it.</p>
 
 <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>
+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
+<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,
@@ -492,7 +492,7 @@ 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
+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>
 
@@ -513,10 +513,10 @@ 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
+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
@@ -544,7 +544,7 @@ or that patent license was granted, prior to 28 March 2007.</p>
 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>
+<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
@@ -584,7 +584,7 @@ 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
+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>
 

app/src/main/assets/mit.html

@@ -1,7 +0,0 @@
-<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/assets/translators.json

@@ -0,0 +1 @@
+{"ar_SA":["abdunnasir"],"bg":["dpa_transifex"],"ca":["Kintu","zagur"],"cs":["pavelb","tomas.odehnal"],"da":["knutztar","mjjzf","Tntdruid_","twikedk"],"de":["anestiskaci","Atalanttore","corppneq","maxkl","nicolas_git","owncube","TheName","Wyrrrd","YvanM"],"el":["anestiskaci","diamond_gr"],"es":["aluaces","Ark74","Elhea","GranPC","jcvielma","plaguna","polkhas","xphnx"],"eu":["cockeredradiation","Osoitz"],"fa":["ahangarha","amiraliakbari","maryambehzi","mtashackori","Numb","taranehsaei"],"fi_FI":["raketti","tseipii"],"fr":["AlainR","alkino2","Amadeen","boutil","callmemagnus","chfo","chrcha","Floflr","grenatrad","Jorg722","Llorc","Novick","Poussinou","Thecross","YvanM","ÉricB."],"fr_FR":["chrcha","Llorc","Poussinou"],"gl":["aluaces","pikamoku"],"hu":["jtg"],"it":["Damtux","ed0","FranzMari","noccio","nwandy","rickyroo","technezio"],"ja":["Naofumi"],"nb_NO":["elonus"],"nl":["davtemp","dehart","toonvangerwen","XtremeNova"],"pl":["gsz","mg6","oskarjakiela","TheName","TORminator"],"pt_BR":["amalvarenga","wanderlei.huttel"],"ru":["aigoshin","anm","astalavister","nick.savin","vaddd"],"sk_SK":["brango67","tiborepcek"],"sl_SI":["MrLaaky","uroszor"],"sr":["daimonion"],"szl":["chlodny"],"tr_TR":["ooguz","pultars"],"uk":["androsua","olexn","twixi007"],"uk_UA":["astalavister"],"zh_CN":["anolir","jxj2zzz79pfp9bpo","linuxbckp","mofitt2016","oksjd","phy","spice2wolf"],"zh_TW":["linuxbckp","mofitt2016","phy"]}

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

@@ -1,464 +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.annotation.SuppressLint;
-import android.annotation.TargetApi;
-import android.app.Notification;
-import android.app.NotificationManager;
-import android.app.PendingIntent;
-import android.content.BroadcastReceiver;
-import android.content.ContentProviderClient;
-import android.content.ContentResolver;
-import android.content.ContentValues;
-import android.content.Context;
-import android.content.Intent;
-import android.content.PeriodicSync;
-import android.database.sqlite.SQLiteDatabase;
-import android.graphics.Bitmap;
-import android.graphics.drawable.BitmapDrawable;
-import android.graphics.drawable.Drawable;
-import android.os.Build;
-import android.os.Bundle;
-import android.provider.CalendarContract;
-import android.provider.ContactsContract;
-import android.support.annotation.NonNull;
-import android.support.annotation.Nullable;
-import android.support.v7.app.NotificationCompat;
-import android.text.TextUtils;
-
-import java.lang.reflect.Method;
-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.Collections;
-import at.bitfire.davdroid.model.ServiceDB.HomeSets;
-import at.bitfire.davdroid.model.ServiceDB.Services;
-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 at.bitfire.vcard4android.GroupMethod;
-import lombok.Cleanup;
-import okhttp3.HttpUrl;
-
-public class AccountSettings {
-    private final static int CURRENT_VERSION = 4;
-    private final static String
-            KEY_SETTINGS_VERSION = "version",
-
-            KEY_USERNAME = "user_name",
-            KEY_AUTH_PREEMPTIVE = "auth_preemptive",
-
-            KEY_WIFI_ONLY = "wifi_only",            // sync on WiFi only (default: false)
-            KEY_WIFI_ONLY_SSID = "wifi_only_ssid";  // restrict sync to specific WiFi SSID
-
-    /** Whether to use RFC 6868 for VCards
-     *  value = null (not existing)      use RFC6868-style encoding (default value)
-     *          "0"                      don't use RFC 6868-style encoding
-     */
-    private final static String KEY_VCARD_RFC6868 = "vcard_rfc6868";
-
-    /** 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;
-
-    /* Whether DAVdroid sets the local calendar color to the value from service DB at every sync
-       value = null (not existing)     true (default)
-               "0"                     false */
-    private final static String KEY_MANAGE_CALENDAR_COLORS = "manage_calendar_colors";
-
-    /** Contact group method:
-        value = null (not existing)     groups as separate VCards (default)
-                "CATEGORIES"            groups are per-contact CATEGORIES
-    */
-    private final static String KEY_CONTACT_GROUP_METHOD = "contact_group_method";
-
-    public final static long SYNC_INTERVAL_MANUALLY = -1;
-
-    final Context context;
-    final AccountManager accountManager;
-    final Account account;
-
-
-    @TargetApi(Build.VERSION_CODES.LOLLIPOP)
-    public AccountSettings(@NonNull Context context, @NonNull Account account) throws InvalidAccountException {
-        this.context = context;
-        this.account = account;
-
-        accountManager = AccountManager.get(context);
-
-        synchronized(AccountSettings.class) {
-            String versionStr = accountManager.getUserData(account, KEY_SETTINGS_VERSION);
-            if (versionStr == null)
-                throw new InvalidAccountException(account);
-
-            int version = 0;
-            try {
-                version = Integer.parseInt(versionStr);
-            } catch (NumberFormatException ignored) {
-            }
-            App.log.info("Account " + account.name + " has version " + version + ", current version: " + CURRENT_VERSION);
-
-            if (version < CURRENT_VERSION) {
-                Bitmap bitmapLogo = null;
-                Drawable drawableLogo = android.os.Build.VERSION.SDK_INT >= android.os.Build.VERSION_CODES.LOLLIPOP ?
-                        context.getDrawable(R.drawable.ic_launcher) :
-                        context.getResources().getDrawable(R.drawable.ic_launcher);
-                if (drawableLogo instanceof BitmapDrawable)
-                    bitmapLogo = ((BitmapDrawable)drawableLogo).getBitmap();
-
-                Notification notify = new NotificationCompat.Builder(context)
-                        .setSmallIcon(R.drawable.ic_new_releases_light)
-                        .setLargeIcon(bitmapLogo)
-                        .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))
-                        .setStyle(new NotificationCompat.BigTextStyle()
-                                .bigText(context.getString(R.string.settings_version_update_settings_updated)))
-                        .setCategory(NotificationCompat.CATEGORY_SYSTEM)
-                        .setPriority(NotificationCompat.PRIORITY_HIGH)
-                        .setContentIntent(PendingIntent.getActivity(context, 0,
-                                new Intent(Intent.ACTION_VIEW, Constants.webUri.buildUpon().appendEncodedPath("faq/entry/davdroid-not-working-after-update/").build()),
-                                PendingIntent.FLAG_CANCEL_CURRENT))
-                        .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 boolean getSyncWifiOnly() {
-        return accountManager.getUserData(account, KEY_WIFI_ONLY) != null;
-    }
-
-    public void setSyncWiFiOnly(boolean wiFiOnly) {
-        accountManager.setUserData(account, KEY_WIFI_ONLY, wiFiOnly ? "1" : null);
-    }
-
-    @Nullable
-    public String getSyncWifiOnlySSID() {
-        return accountManager.getUserData(account, KEY_WIFI_ONLY_SSID);
-    }
-
-    public void setSyncWifiOnlySSID(String ssid) {
-        accountManager.setUserData(account, KEY_WIFI_ONLY_SSID, ssid);
-    }
-
-
-    // CardDAV settings
-
-    public boolean getVCardRFC6868() {
-        return accountManager.getUserData(account, KEY_VCARD_RFC6868) == null;
-    }
-
-    public void setVCardRFC6868(boolean use) {
-        accountManager.setUserData(account, KEY_VCARD_RFC6868, use ? null : "0");
-    }
-
-
-    // CalDAV settings
-
-    @Nullable
-    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(@Nullable Integer days) {
-        accountManager.setUserData(account, KEY_TIME_RANGE_PAST_DAYS, String.valueOf(days == null ? -1 : days));
-    }
-
-    public boolean getManageCalendarColors() {
-        return accountManager.getUserData(account, KEY_MANAGE_CALENDAR_COLORS) == null;
-    }
-
-    public void setManageCalendarColors(boolean manage) {
-        accountManager.setUserData(account, KEY_MANAGE_CALENDAR_COLORS, manage ? null : "0");
-    }
-
-
-    // CardDAV settings
-
-    @NonNull
-    public GroupMethod getGroupMethod() {
-        final String name = accountManager.getUserData(account, KEY_CONTACT_GROUP_METHOD);
-        return name != null ?
-                GroupMethod.valueOf(name) :
-                GroupMethod.GROUP_VCARDS;
-    }
-
-    public void setGroupMethod(@NonNull GroupMethod method) {
-        final String name = method == GroupMethod.GROUP_VCARDS ? null : method.name();
-        accountManager.setUserData(account, KEY_CONTACT_GROUP_METHOD, name);
-    }
-
-
-    // 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);
-                accountManager.setUserData(account, KEY_SETTINGS_VERSION, String.valueOf(toVersion));
-            } catch (Exception e) {
-                App.log.log(Level.SEVERE, "Couldn't update account settings", e);
-            }
-            fromVersion = toVersion;
-        }
-    }
-
-    @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);
-    }
-
-    @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);
-        }
-    }
-
-    @SuppressWarnings({ "Recycle", "unused" })
-    private void update_3_4() {
-        setGroupMethod(GroupMethod.CATEGORIES);
-    }
-
-
-    public static class AppUpdatedReceiver extends BroadcastReceiver {
-
-        @Override
-        @SuppressLint("UnsafeProtectedBroadcastReceiver")
-        public void onReceive(Context context, Intent intent) {
-            App.log.info("DAVdroid was updated, checking for AccountSettings version");
-
-            // peek into AccountSettings to initiate a possible migration
-            AccountManager accountManager = AccountManager.get(context);
-            for (Account account : accountManager.getAccountsByType(Constants.ACCOUNT_TYPE))
-                try {
-                    App.log.info("Checking account " + account.name);
-                    new AccountSettings(context, account);
-                } catch (InvalidAccountException e) {
-                    App.log.log(Level.SEVERE, "Couldn't check for updated account settings", e);
-                }
-        }
-
-    }
-
-}

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

@@ -1,145 +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.app.Application;
-import android.app.NotificationManager;
-import android.content.BroadcastReceiver;
-import android.content.Context;
-import android.content.Intent;
-import android.graphics.drawable.BitmapDrawable;
-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.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 at.bitfire.davdroid.model.ServiceDB;
-import at.bitfire.davdroid.model.Settings;
-import de.duenndns.ssl.MemorizingTrustManager;
-import lombok.Cleanup;
-import lombok.Getter;
-import okhttp3.internal.tls.OkHostnameVerifier;
-
-public class App extends Application {
-    public static final String FLAVOR_GOOGLE_PLAY = "gplay";
-
-    public static final String LOG_TO_EXTERNAL_STORAGE = "logToExternalStorage";
-
-    @Getter
-    private static MemorizingTrustManager memorizingTrustManager;
-
-    @Getter
-    private static SSLSocketFactoryCompat sslSocketFactoryCompat;
-
-    @Getter
-    private static HostnameVerifier hostnameVerifier;
-
-    public final static Logger log = Logger.getLogger("davdroid");
-    static {
-        at.bitfire.dav4android.Constants.log = Logger.getLogger("davdroid.dav4android");
-    }
-
-    @Override
-    public void onCreate() {
-        super.onCreate();
-
-        // initialize MemorizingTrustManager
-        memorizingTrustManager = new MemorizingTrustManager(this);
-        sslSocketFactoryCompat = new SSLSocketFactoryCompat(memorizingTrustManager);
-        hostnameVerifier = memorizingTrustManager.wrapHostnameVerifier(OkHostnameVerifier.INSTANCE);
-
-        // initializer logger
-        reinitLogger();
-    }
-
-    public void reinitLogger() {
-        // don't use Android default logging, we have our own handlers
-        log.setUseParentHandlers(false);
-
-        @Cleanup ServiceDB.OpenHelper dbHelper = new ServiceDB.OpenHelper(this);
-        Settings settings = new Settings(dbHelper.getReadableDatabase());
-
-        boolean logToFile = settings.getBoolean(LOG_TO_EXTERNAL_STORAGE, 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 fileName = new File(dir, "davdroid-" + android.os.Process.myPid() + "-" +
-                            DateFormatUtils.format(System.currentTimeMillis(), "yyyyMMdd-HHmmss") + ".txt").toString();
-                    log.info("Logging to " + fileName);
-
-                    FileHandler fileHandler = new FileHandler(fileName);
-                    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);
-    }
-
-
-    public static class ReinitLoggingReceiver extends BroadcastReceiver {
-
-        @Override
-        public void onReceive(Context context, Intent intent) {
-            log.info("Received broadcast: re-initializing logger");
-
-            App app = (App)context.getApplicationContext();
-            app.reinitLogger();
-        }
-
-    }
-}

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

@@ -0,0 +1,101 @@
+/*
+ * 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.content.Intent
+import android.content.IntentFilter
+import android.graphics.Bitmap
+import android.graphics.drawable.BitmapDrawable
+import android.net.Uri
+import android.os.Build
+import android.os.StrictMode
+import androidx.appcompat.app.AppCompatDelegate
+import androidx.appcompat.content.res.AppCompatResources
+import at.bitfire.davdroid.log.Logger
+import at.bitfire.davdroid.ui.DebugInfoActivity
+import at.bitfire.davdroid.ui.NotificationUtils
+import java.util.logging.Level
+import kotlin.concurrent.thread
+import kotlin.system.exitProcess
+
+@Suppress("unused")
+class App: Application(), Thread.UncaughtExceptionHandler {
+
+    companion object {
+
+        fun getLauncherBitmap(context: Context): Bitmap? {
+            val drawableLogo = AppCompatResources.getDrawable(context, R.mipmap.ic_launcher)
+            return if (drawableLogo is BitmapDrawable)
+                drawableLogo.bitmap
+            else
+                null
+        }
+
+        fun homepageUrl(context: Context) =
+                Uri.parse(context.getString(R.string.homepage_url)).buildUpon()
+                        .appendQueryParameter("pk_campaign", BuildConfig.APPLICATION_ID)
+                        .appendQueryParameter("pk_kwd", context::class.java.simpleName)
+                        .appendQueryParameter("app-version", BuildConfig.VERSION_NAME)
+                        .build()!!
+
+    }
+
+
+    override fun onCreate() {
+        super.onCreate()
+        Logger.initialize(this)
+
+        if (BuildConfig.DEBUG)
+            // debug builds
+            StrictMode.setVmPolicy(StrictMode.VmPolicy.Builder()
+                    .detectActivityLeaks()
+                    .detectFileUriExposure()
+                    .detectLeakedClosableObjects()
+                    .detectLeakedRegistrationObjects()
+                    .detectLeakedSqlLiteObjects()
+                    .penaltyLog()
+                    .build())
+        else // if (BuildConfig.FLAVOR == FLAVOR_STANDARD)
+            // handle uncaught exceptions in non-debug standard flavor
+            Thread.setDefaultUncaughtExceptionHandler(this)
+
+        if (Build.VERSION.SDK_INT <= 21)
+            AppCompatDelegate.setCompatVectorFromResourcesEnabled(true)
+
+        NotificationUtils.createChannels(this)
+
+        // don't block UI for some background checks
+        thread {
+            // watch installed/removed apps
+            val tasksFilter = IntentFilter(Intent.ACTION_PACKAGE_ADDED).apply {
+                addAction(Intent.ACTION_PACKAGE_FULLY_REMOVED)
+                addAction(Intent.ACTION_PACKAGE_REMOVED)
+                addDataScheme("package")
+            }
+            registerReceiver(PackageChangedReceiver(), tasksFilter)
+
+            // check whether a tasks app is currently installed
+            PackageChangedReceiver.updateTaskSync(this)
+        }
+    }
+
+    override fun uncaughtException(t: Thread, e: Throwable) {
+        Logger.log.log(Level.SEVERE, "Unhandled exception!", e)
+
+        val intent = Intent(this, DebugInfoActivity::class.java)
+        intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK)
+        intent.putExtra(DebugInfoActivity.KEY_THROWABLE, e)
+        startActivity(intent)
+
+        exitProcess(1)
+    }
+
+}

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/CompatUtils.kt

@@ -0,0 +1,12 @@
+package at.bitfire.davdroid
+
+import android.content.ContentProviderClient
+import android.os.Build
+
+@Suppress("DEPRECATION")
+fun ContentProviderClient.closeCompat() {
+    if (Build.VERSION.SDK_INT >= 24)
+        close()
+    else
+        release()
+}

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

@@ -1,29 +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_REFRESH_COLLECTIONS = 2,
-            NOTIFICATION_CONTACTS_SYNC = 10,
-            NOTIFICATION_CALENDAR_SYNC = 11,
-            NOTIFICATION_TASK_SYNC = 12,
-            NOTIFICATION_PERMISSIONS = 20;
-
-    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 +1,30 @@
+/*
+ * 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
+
+object Constants {
+
+    const val DAVDROID_GREEN_RGBA = 0xFF8bc34a.toInt()
+
+    const val DEFAULT_SYNC_INTERVAL = 4 * 3600L    // 4 hours
+
+    /**
+     * Context label for [org.apache.commons.lang3.exception.ContextedException].
+     * Context value is the [at.bitfire.davdroid.resource.LocalResource]
+     * which is related to the exception cause.
+     */
+    const val EXCEPTION_CONTEXT_LOCAL_RESOURCE = "localResource"
+
+    /**
+     * Context label for [org.apache.commons.lang3.exception.ContextedException].
+     * Context value is the [okhttp3.HttpUrl] of the remote resource
+     * which is related to the exception cause.
+     */
+    const val EXCEPTION_CONTEXT_REMOTE_RESOURCE = "remoteResource"
+
+}

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

@@ -1,427 +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.Notification;
-import android.app.NotificationManager;
-import android.app.PendingIntent;
-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.graphics.drawable.BitmapDrawable;
-import android.os.Binder;
-import android.os.IBinder;
-import android.support.annotation.NonNull;
-import android.support.annotation.Nullable;
-import android.support.v7.app.NotificationCompat;
-import android.text.TextUtils;
-
-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.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.property.AddressbookHomeSet;
-import at.bitfire.dav4android.property.CalendarHomeSet;
-import at.bitfire.dav4android.property.CalendarProxyReadFor;
-import at.bitfire.dav4android.property.CalendarProxyWriteFor;
-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 at.bitfire.davdroid.ui.DebugInfoActivity;
-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<WeakReference<RefreshingStatusListener>> refreshingStatusListeners = new LinkedList<>();
-
-
-    @Override
-    public int onStartCommand(Intent intent, int flags, int startId) {
-        if (intent != null) {
-            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 (WeakReference<RefreshingStatusListener> ref : refreshingStatusListeners) {
-                            RefreshingStatusListener listener = ref.get();
-                            if (listener != null)
-                                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(@NonNull RefreshingStatusListener listener, boolean callImmediate) {
-            refreshingStatusListeners.add(new WeakReference<>(listener));
-            if (callImmediate)
-                for (long id : runningRefresh)
-                    listener.onDavRefreshStatusChanged(id, true);
-        }
-
-        public void removeRefreshingStatusListener(@NonNull RefreshingStatusListener listener) {
-            for (Iterator<WeakReference<RefreshingStatusListener>> iterator = refreshingStatusListeners.iterator(); iterator.hasNext(); ) {
-                RefreshingStatusListener item = iterator.next().get();
-                if (listener.equals(item))
-                    iterator.remove();
-            }
-        }
-    }
-
-
-    /* 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() {
-            Account account = null;
-
-            try {
-                db = dbHelper.getWritableDatabase();
-
-                String serviceType = serviceType();
-                App.log.info("Refreshing " + serviceType + " collections of service #" + service);
-
-                // get account
-                account = account();
-
-                // create authenticating OkHttpClient (credentials taken from account settings)
-                OkHttpClient httpClient = HttpClient.create(DavService.this, account);
-
-                // 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, dav, homeSets);
-
-                    // refresh home sets: calendar-proxy-read/write-for
-                    CalendarProxyReadFor proxyRead = (CalendarProxyReadFor)dav.properties.get(CalendarProxyReadFor.NAME);
-                    if (proxyRead != null)
-                        for (String href : proxyRead.principals) {
-                            App.log.fine("Principal is a read-only proxy for " + href + ", checking for home sets");
-                            queryHomeSets(serviceType, new DavResource(httpClient, dav.location.resolve(href)), homeSets);
-                        }
-                    CalendarProxyWriteFor proxyWrite = (CalendarProxyWriteFor)dav.properties.get(CalendarProxyWriteFor.NAME);
-                    if (proxyWrite != null)
-                        for (String href : proxyWrite.principals) {
-                            App.log.fine("Principal is a read-write proxy for " + href + ", checking for home sets");
-                            queryHomeSets(serviceType, new DavResource(httpClient, dav.location.resolve(href)), 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("Principal is member of group " + href + ", checking for home sets");
-                            DavResource group = new DavResource(httpClient, dav.location.resolve(href));
-                            try {
-                                queryHomeSets(serviceType, group, homeSets);
-                            } catch(HttpException|DavException e) {
-                                App.log.log(Level.WARNING, "Couldn't query member group ", e);
-                            }
-                        }
-                }
-
-                // 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> itHomeSets = homeSets.iterator(); itHomeSets.hasNext(); ) {
-                    HttpUrl homeSet = itHomeSets.next();
-                    App.log.fine("Listing home set " + homeSet);
-
-                    DavResource dav = new DavResource(httpClient, homeSet);
-                    try {
-                        dav.propfind(1, CollectionInfo.DAV_PROPERTIES);
-                        IteratorChain<DavResource> itCollections = new IteratorChain<>(dav.members.iterator(), new SingletonIterator(dav));
-                        while (itCollections.hasNext()) {
-                            DavResource member = itCollections.next();
-                            CollectionInfo info = CollectionInfo.fromDavResource(member);
-                            info.confirmed = true;
-                            App.log.log(Level.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(HttpException e) {
-                        if (e.status == 403 || e.status == 404 || e.status == 410)
-                            // delete home set only if it was not accessible (40x)
-                            itHomeSets.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(HttpException e) {
-                            if (e.status == 403 || e.status == 404 || e.status == 410)
-                                // delete collection only if it was not accessible (40x)
-                                iterator.remove();
-                            else
-                                throw e;
-                        }
-                }
-
-                // restore selections
-                for (HttpUrl url : selectedCollections) {
-                    CollectionInfo info = collections.get(url);
-                    if (info != null)
-                        info.selected = true;
-                }
-
-                try {
-                    db.beginTransactionNonExclusive();
-                    saveHomeSets(homeSets);
-                    saveCollections(collections.values());
-                    db.setTransactionSuccessful();
-                } finally {
-                    db.endTransaction();
-                }
-
-            } catch(InvalidAccountException e) {
-                App.log.log(Level.SEVERE, "Invalid account", e);
-            } catch(IOException|HttpException|DavException e) {
-                App.log.log(Level.SEVERE, "Couldn't refresh collection list", e);
-
-                Intent debugIntent = new Intent(DavService.this, DebugInfoActivity.class);
-                debugIntent.putExtra(DebugInfoActivity.KEY_THROWABLE, e);
-                if (account != null)
-                    debugIntent.putExtra(DebugInfoActivity.KEY_ACCOUNT, account);
-
-                NotificationManager nm = (NotificationManager)getSystemService(NOTIFICATION_SERVICE);
-                Notification notify = new NotificationCompat.Builder(DavService.this)
-                        .setSmallIcon(R.drawable.ic_error_light)
-                        .setLargeIcon(((BitmapDrawable)getResources().getDrawable(R.drawable.ic_launcher)).getBitmap())
-                        .setContentTitle(getString(R.string.dav_service_refresh_failed))
-                        .setContentText(getString(R.string.dav_service_refresh_couldnt_refresh))
-                        .setContentIntent(PendingIntent.getActivity(DavService.this, 0, debugIntent, PendingIntent.FLAG_UPDATE_CURRENT))
-                        .build();
-                nm.notify(Constants.NOTIFICATION_REFRESH_COLLECTIONS, notify);
-            } finally {
-                dbHelper.close();
-
-                runningRefresh.remove(service);
-                for (WeakReference<RefreshingStatusListener> ref : refreshingStatusListeners) {
-                    RefreshingStatusListener listener = ref.get();
-                    if (listener != null)
-                        listener.onDavRefreshStatusChanged(service, false);
-                }
-            }
-        }
-
-        /**
-         * Checks if the given URL defines home sets and adds them to the home set list.
-         * @param serviceType       CalDAV/CardDAV (calendar home set / addressbook home set)
-         * @param dav               DavResource to check
-         * @param homeSets          set where found home set URLs will be put into
-         */
-        private void queryHomeSets(String serviceType, DavResource dav, Set<HttpUrl> homeSets) throws IOException, HttpException, DavException {
-            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, CalendarProxyReadFor.NAME, CalendarProxyWriteFor.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)));
-            }
-        }
-
-
-        @NonNull
-        private Account account() {
-            @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()) {
-                return new Account(cursor.getString(0), Constants.ACCOUNT_TYPE);
-            } else
-                throw new IllegalArgumentException("Service not found");
-        }
-
-        @NonNull
-        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");
-        }
-
-        @Nullable
-        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;
-        }
-
-        @NonNull
-        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);
-            }
-        }
-
-        @NonNull
-        private Map<HttpUrl, CollectionInfo> readCollections() {
-            Map<HttpUrl, CollectionInfo> collections = new LinkedHashMap<>();
-            @Cleanup Cursor cursor = db.query(Collections._TABLE, null, 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 +1,375 @@
+/*
+ * 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.content.ContentResolver
+import android.content.Intent
+import android.os.Binder
+import android.os.Bundle
+import androidx.core.app.NotificationCompat
+import androidx.core.app.NotificationManagerCompat
+import androidx.room.Transaction
+import at.bitfire.dav4jvm.DavResource
+import at.bitfire.dav4jvm.Response
+import at.bitfire.dav4jvm.UrlUtils
+import at.bitfire.dav4jvm.exception.HttpException
+import at.bitfire.dav4jvm.property.*
+import at.bitfire.davdroid.log.Logger
+import at.bitfire.davdroid.model.*
+import at.bitfire.davdroid.model.Collection
+import at.bitfire.davdroid.settings.AccountSettings
+import at.bitfire.davdroid.ui.DebugInfoActivity
+import at.bitfire.davdroid.ui.NotificationUtils
+import okhttp3.HttpUrl
+import okhttp3.OkHttpClient
+import java.lang.ref.WeakReference
+import java.util.*
+import java.util.logging.Level
+import kotlin.concurrent.thread
+
+class DavService: android.app.Service() {
+
+    companion object {
+        const val ACTION_REFRESH_COLLECTIONS = "refreshCollections"
+        const val EXTRA_DAV_SERVICE_ID = "davServiceID"
+
+        /** Initialize a forced synchronization. Expects intent data
+            to be an URI of this format:
+            contents://<authority>/<account.type>/<account name>
+         **/
+        const val ACTION_FORCE_SYNC = "forceSync"
+
+        val DAV_COLLECTION_PROPERTIES = arrayOf(
+                ResourceType.NAME,
+                CurrentUserPrivilegeSet.NAME,
+                DisplayName.NAME,
+                AddressbookDescription.NAME, SupportedAddressData.NAME,
+                CalendarDescription.NAME, CalendarColor.NAME, SupportedCalendarComponentSet.NAME,
+                Source.NAME
+        )
+
+    }
+
+    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)) {
+                        refreshingStatusListeners.forEach { listener ->
+                            listener.get()?.onDavRefreshStatusChanged(id, true)
+                        }
+                        thread { refreshCollections(id) }
+                    }
+
+                ACTION_FORCE_SYNC -> {
+                    val uri = intent.data!!
+                    val authority = uri.authority!!
+                    val account = Account(
+                            uri.pathSegments[1],
+                            uri.pathSegments[0]
+                    )
+                    forceSync(authority, account)
+                }
+            }
+        }
+
+        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, callImmediateIfRunning: Boolean) {
+            refreshingStatusListeners += WeakReference<RefreshingStatusListener>(listener)
+            if (callImmediateIfRunning)
+                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 forceSync(authority: String, account: Account) {
+        Logger.log.info("Forcing $authority synchronization of $account")
+        val extras = Bundle(2)
+        extras.putBoolean(ContentResolver.SYNC_EXTRAS_MANUAL, true)        // manual sync
+        extras.putBoolean(ContentResolver.SYNC_EXTRAS_EXPEDITED, true)     // run immediately (don't queue)
+        ContentResolver.requestSync(account, authority, extras)
+    }
+
+    private fun refreshCollections(serviceId: Long) {
+        val db = AppDatabase.getInstance(this)
+        val homeSetDao = db.homeSetDao()
+        val collectionDao = db.collectionDao()
+
+        val service = db.serviceDao().get(serviceId) ?: throw IllegalArgumentException("Service not found")
+        val account = Account(service.accountName, getString(R.string.account_type))
+
+        val homeSets = homeSetDao.getByService(serviceId).associateBy { it.url }.toMutableMap()
+        val collections = collectionDao.getByService(serviceId).associateBy { it.url }.toMutableMap()
+
+        /**
+         * Checks if the given URL defines home sets and adds them to the home set list.
+         *
+         * @throws java.io.IOException
+         * @throws HttpException
+         * @throws at.bitfire.dav4jvm.exception.DavException
+         */
+        fun queryHomeSets(client: OkHttpClient, url: HttpUrl, recurse: Boolean = true) {
+            val related = mutableSetOf<HttpUrl>()
+
+            fun findRelated(root: HttpUrl, dav: Response) {
+                // refresh home sets: calendar-proxy-read/write-for
+                dav[CalendarProxyReadFor::class.java]?.let {
+                    for (href in it.hrefs) {
+                        Logger.log.fine("Principal is a read-only proxy for $href, checking for home sets")
+                        root.resolve(href)?.let { proxyReadFor ->
+                            related += proxyReadFor
+                        }
+                    }
+                }
+                dav[CalendarProxyWriteFor::class.java]?.let {
+                    for (href in it.hrefs) {
+                        Logger.log.fine("Principal is a read/write proxy for $href, checking for home sets")
+                        root.resolve(href)?.let { proxyWriteFor ->
+                            related += proxyWriteFor
+                        }
+                    }
+                }
+
+                // refresh home sets: direct group memberships
+                dav[GroupMembership::class.java]?.let {
+                    for (href in it.hrefs) {
+                        Logger.log.fine("Principal is member of group $href, checking for home sets")
+                        root.resolve(href)?.let { groupMembership ->
+                            related += groupMembership
+                        }
+                    }
+                }
+            }
+
+            val dav = DavResource(client, url)
+            when (service.type) {
+                Service.TYPE_CARDDAV ->
+                    try {
+                        dav.propfind(0, DisplayName.NAME, AddressbookHomeSet.NAME, GroupMembership.NAME) { response, _ ->
+                            response[AddressbookHomeSet::class.java]?.let { homeSet ->
+                                for (href in homeSet.hrefs)
+                                    dav.location.resolve(href)?.let {
+                                        val foundUrl = UrlUtils.withTrailingSlash(it)
+                                        homeSets[foundUrl] = HomeSet(0, service.id, foundUrl)
+                                    }
+                            }
+
+                            if (recurse)
+                                findRelated(dav.location, response)
+                        }
+                    } catch (e: HttpException) {
+                        if (e.code/100 == 4)
+                            Logger.log.log(Level.INFO, "Ignoring Client Error 4xx while looking for addressbook home sets", e)
+                        else
+                            throw e
+                    }
+                Service.TYPE_CALDAV -> {
+                    try {
+                        dav.propfind(0, DisplayName.NAME, CalendarHomeSet.NAME, CalendarProxyReadFor.NAME, CalendarProxyWriteFor.NAME, GroupMembership.NAME) { response, _ ->
+                            response[CalendarHomeSet::class.java]?.let { homeSet ->
+                                for (href in homeSet.hrefs)
+                                    dav.location.resolve(href)?.let {
+                                        val foundUrl = UrlUtils.withTrailingSlash(it)
+                                        homeSets[foundUrl] = HomeSet(0, service.id, foundUrl)
+                                    }
+                            }
+
+                            if (recurse)
+                                findRelated(dav.location, response)
+                        }
+                    } catch (e: HttpException) {
+                        if (e.code/100 == 4)
+                            Logger.log.log(Level.INFO, "Ignoring Client Error 4xx while looking for calendar home sets", e)
+                        else
+                            throw e
+                    }
+                }
+            }
+
+            for (resource in related)
+                queryHomeSets(client, resource, false)
+        }
+
+        @Transaction
+        fun saveHomesets() {
+            DaoTools(homeSetDao).syncAll(
+                    homeSetDao.getByService(serviceId),
+                    homeSets,
+                    { it.url })
+        }
+
+        @Transaction
+        fun saveCollections() {
+            DaoTools(collectionDao).syncAll(
+                    collectionDao.getByService(serviceId),
+                    collections, { it.url }) { new, old ->
+                new.forceReadOnly = old.forceReadOnly
+                new.sync = old.sync
+            }
+        }
+
+        fun saveResults() {
+            saveHomesets()
+            saveCollections()
+        }
+
+        try {
+            Logger.log.info("Refreshing ${service.type} collections of service #$service")
+
+            // cancel previous notification
+            NotificationManagerCompat.from(this)
+                    .cancel(service.toString(), NotificationUtils.NOTIFY_REFRESH_COLLECTIONS)
+
+            // create authenticating OkHttpClient (credentials taken from account settings)
+            HttpClient.Builder(this, AccountSettings(this, account))
+                    .setForeground(true)
+                    .build().use { client ->
+                val httpClient = client.okHttpClient
+
+                // refresh home set list (from principal)
+                service.principal?.let { principalUrl ->
+                    Logger.log.fine("Querying principal $principalUrl for home sets")
+                    queryHomeSets(httpClient, principalUrl)
+                }
+
+                // now refresh homesets and their member collections
+                val itHomeSets = homeSets.iterator()
+                while (itHomeSets.hasNext()) {
+                    val homeSet = itHomeSets.next()
+                    Logger.log.fine("Listing home set ${homeSet.key}")
+
+                    try {
+                        DavResource(httpClient, homeSet.key).propfind(1, *DAV_COLLECTION_PROPERTIES) { response, relation ->
+                            if (!response.isSuccess())
+                                return@propfind
+
+                            if (relation == Response.HrefRelation.SELF) {
+                                // this response is about the homeset itself
+                                homeSet.value.displayName = response[DisplayName::class.java]?.displayName
+                                homeSet.value.privBind = response[CurrentUserPrivilegeSet::class.java]?.mayBind ?: true
+                            }
+
+                            // in any case, check whether the response is about a useable collection
+                            val info = Collection.fromDavResponse(response) ?: return@propfind
+                            info.serviceId = serviceId
+                            info.confirmed = true
+                            Logger.log.log(Level.FINE, "Found collection", info)
+
+                            // remember usable collections
+                            if ((service.type == Service.TYPE_CARDDAV && info.type == Collection.TYPE_ADDRESSBOOK) ||
+                                    (service.type == Service.TYPE_CALDAV && arrayOf(Collection.TYPE_CALENDAR, Collection.TYPE_WEBCAL).contains(info.type)))
+                                collections[response.href] = info
+                        }
+                    } catch(e: HttpException) {
+                        if (e.code 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 {
+                            DavResource(httpClient, url).propfind(0, *DAV_COLLECTION_PROPERTIES) { response, _ ->
+                                if (!response.isSuccess())
+                                    return@propfind
+
+                                val collection = Collection.fromDavResponse(response) ?: return@propfind
+                                collection.confirmed = true
+
+                                // remove unusable collections
+                                if ((service.type == Service.TYPE_CARDDAV && collection.type != Collection.TYPE_ADDRESSBOOK) ||
+                                    (service.type == Service.TYPE_CALDAV && !arrayOf(Collection.TYPE_CALENDAR, Collection.TYPE_WEBCAL).contains(collection.type)) ||
+                                    (collection.type == Collection.TYPE_WEBCAL && collection.source == null))
+                                    itCollections.remove()
+                            }
+                        } catch(e: HttpException) {
+                            if (e.code in arrayOf(403, 404, 410))
+                            // delete collection only if it was not accessible (40x)
+                                itCollections.remove()
+                            else
+                                throw e
+                        }
+                }
+            }
+
+            saveResults()
+
+        } 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, DebugInfoActivity::class.java)
+            debugIntent.putExtra(DebugInfoActivity.KEY_THROWABLE, e)
+            debugIntent.putExtra(DebugInfoActivity.KEY_ACCOUNT, account)
+
+            val notify = NotificationUtils.newBuilder(this, NotificationUtils.CHANNEL_GENERAL)
+                    .setSmallIcon(R.drawable.ic_sync_problem_notify)
+                    .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))
+                    .setSubText(account.name)
+                    .setCategory(NotificationCompat.CATEGORY_ERROR)
+                    .build()
+            NotificationManagerCompat.from(this)
+                    .notify(serviceId.toString(), NotificationUtils.NOTIFY_REFRESH_COLLECTIONS, notify)
+        } finally {
+            runningRefresh.remove(serviceId)
+            refreshingStatusListeners.mapNotNull { it.get() }.forEach {
+                it.onDavRefreshStatusChanged(serviceId, false)
+            }
+        }
+
+    }
+
+}

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

@@ -1,41 +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.support.annotation.NonNull;
-
-import org.apache.commons.lang3.StringUtils;
-
-import java.util.Collections;
-import java.util.LinkedList;
-import java.util.List;
-
-import okhttp3.HttpUrl;
-
-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);
-    }
-
-    public static String lastSegmentOfUrl(@NonNull String url) {
-        // the list returned by HttpUrl.pathSegments() is unmodifiable, so we have to create a copy
-        List<String> segments = new LinkedList<>(HttpUrl.parse(url).pathSegments());
-        Collections.reverse(segments);
-
-        for (String segment : segments)
-            if (!StringUtils.isEmpty(segment))
-                return segment;
-
-        return "/";
-    }
-
-}

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

@@ -0,0 +1,108 @@
+/*
+ * 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.TargetApi
+import android.content.ContentResolver
+import android.content.Context
+import android.net.ConnectivityManager
+import android.os.Build
+import android.os.Bundle
+import android.provider.CalendarContract
+import at.bitfire.davdroid.log.Logger
+import at.bitfire.ical4android.TaskProvider
+import okhttp3.HttpUrl
+import org.xbill.DNS.*
+import java.util.*
+
+/**
+ * Some WebDAV and related network utility methods
+ */
+object DavUtils {
+
+    @Suppress("FunctionName")
+    fun ARGBtoCalDAVColor(colorWithAlpha: Int): String {
+        val alpha = (colorWithAlpha shr 24) and 0xFF
+        val color = colorWithAlpha and 0xFFFFFF
+        return String.format("#%06X%02X", color, alpha)
+    }
+
+
+    fun lastSegmentOfUrl(url: HttpUrl): String {
+        // the list returned by HttpUrl.pathSegments() is unmodifiable, so we have to create a copy
+        val segments = LinkedList<String>(url.pathSegments)
+        segments.reverse()
+
+        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)
+            if (activeLink != null) {
+                // get DNS servers of active network link and set them for dnsjava so that it can send SRV queries
+                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)
+            } else
+                Logger.log.severe("Couldn't determine DNS servers, dnsjava queries (SRV/TXT records) won't work")
+        }
+    }
+
+    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
+    }
+
+
+    fun requestSync(context: Context, account: Account) {
+        val authorities = arrayOf(
+                context.getString(R.string.address_books_authority),
+                CalendarContract.AUTHORITY,
+                TaskProvider.ProviderName.OpenTasks.authority
+        )
+
+        for (authority in authorities) {
+            val extras = Bundle(2)
+            extras.putBoolean(ContentResolver.SYNC_EXTRAS_MANUAL, true)        // manual sync
+            extras.putBoolean(ContentResolver.SYNC_EXTRAS_EXPEDITED, true)     // run immediately (don't queue)
+            ContentResolver.requestSync(account, authority, extras)
+        }
+    }
+}

app/src/main/java/at/bitfire/davdroid/HttpClient.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;
-
-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(@NonNull Context context, @NonNull Account account, @NonNull final Logger logger) throws InvalidAccountException {
-        OkHttpClient.Builder builder = defaultBuilder(logger);
-
-        // 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()));
-
-        return builder.build();
-    }
-
-    public static OkHttpClient create(@NonNull Logger logger) {
-        return defaultBuilder(logger).build();
-    }
-
-    public static OkHttpClient create(@NonNull Context context, @NonNull Account account) throws InvalidAccountException {
-        return create(context, account, App.log);
-    }
-
-    public static OkHttpClient create() {
-        return create(App.log);
-    }
-
-    private static OkHttpClient.Builder defaultBuilder(@NonNull final Logger logger) {
-        OkHttpClient.Builder builder = client.newBuilder();
-
-        // use MemorizingTrustManager to manage self-signed certificates
-        if (App.getSslSocketFactoryCompat() != null)
-            builder.sslSocketFactory(App.getSslSocketFactoryCompat(), App.getMemorizingTrustManager());
-        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(new MemoryCookieStore());
-
-        // add network logging, if requested
-        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;
-    }
-
-    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 {
-            App.log.fine("Adding basic authorization header for user " + username);
-            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 +1,263 @@
+/*
+ * 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.dav4jvm.BasicDigestAuthHandler
+import at.bitfire.dav4jvm.UrlUtils
+import at.bitfire.davdroid.log.Logger
+import at.bitfire.davdroid.model.Credentials
+import at.bitfire.davdroid.settings.AccountSettings
+import at.bitfire.davdroid.settings.Settings
+import okhttp3.*
+import okhttp3.brotli.BrotliInterceptor
+import okhttp3.internal.tls.OkHostnameVerifier
+import okhttp3.logging.HttpLoggingInterceptor
+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.SimpleDateFormat
+import java.util.*
+import java.util.concurrent.TimeUnit
+import java.util.logging.Level
+import javax.net.ssl.*
+
+class HttpClient private constructor(
+        val okHttpClient: OkHttpClient,
+        private val certManager: CustomCertManager?
+): AutoCloseable {
+
+    companion object {
+        /** max. size of disk cache (10 MB) */
+        const val DISK_CACHE_MAX_SIZE: Long = 10*1024*1024
+
+        /** [OkHttpClient] singleton to build all clients from */
+        val sharedClient: OkHttpClient = OkHttpClient.Builder()
+                // set timeouts
+                .connectTimeout(15, TimeUnit.SECONDS)
+                .writeTimeout(30, TimeUnit.SECONDS)
+                .readTimeout(120, TimeUnit.SECONDS)
+
+                // keep TLS 1.0 and 1.1 for now; remove when major browsers have dropped it (probably 2020)
+                .connectionSpecs(listOf(
+                        ConnectionSpec.CLEARTEXT,
+                        ConnectionSpec.COMPATIBLE_TLS
+                ))
+
+                // don't allow redirects by default, because it would break PROPFIND handling
+                .followRedirects(false)
+
+                // offer Brotli and gzip compression
+                .addInterceptor(BrotliInterceptor)
+
+                // add User-Agent to every request
+                .addNetworkInterceptor(UserAgentInterceptor)
+
+                .build()
+    }
+
+
+    override fun close() {
+        okHttpClient.cache?.close()
+        certManager?.close()
+    }
+
+    class Builder(
+            val context: Context? = null,
+            accountSettings: AccountSettings? = null,
+            val logger: java.util.logging.Logger = Logger.log
+    ) {
+        private var certManager: CustomCertManager? = null
+        private var certificateAlias: String? = null
+        private var cache: Cache? = 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(object: HttpLoggingInterceptor.Logger {
+                    override fun log(message: String) {
+                        logger.finest(message)
+                    }
+                })
+                loggingInterceptor.level = HttpLoggingInterceptor.Level.BODY
+                orig.addInterceptor(loggingInterceptor)
+            }
+
+            context?.let {
+                val settings = Settings.getInstance(context)
+
+                // custom proxy support
+                try {
+                    if (settings.getBoolean(Settings.OVERRIDE_PROXY) == true) {
+                        val address = InetSocketAddress(
+                                settings.getString(Settings.OVERRIDE_PROXY_HOST)
+                                        ?: Settings.OVERRIDE_PROXY_HOST_DEFAULT,
+                                settings.getInt(Settings.OVERRIDE_PROXY_PORT)
+                                        ?: Settings.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)
+                }
+
+                //if (BuildConfig.customCerts)
+                    customCertManager(CustomCertManager(context, true,
+                            !(settings.getBoolean(Settings.DISTRUST_SYSTEM_CERTIFICATES)
+                                    ?: Settings.DISTRUST_SYSTEM_CERTIFICATES_DEFAULT)))
+            }
+
+            // 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).filterNotNull()) {
+                if (dir.exists() && dir.canWrite()) {
+                    val cacheDir = File(dir, "HttpClient")
+                    cacheDir.mkdir()
+                    Logger.log.fine("Using disk cache: $cacheDir")
+                    orig.cache(Cache(cacheDir, DISK_CACHE_MAX_SIZE))
+                    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)
+                    ?: OkHostnameVerifier
+
+            var keyManager: KeyManager? = null
+            certificateAlias?.let { alias ->
+                try {
+                    val context = requireNotNull(context)
+
+                    // get provider certificate and private key
+                    val certs = KeyChain.getCertificateChain(context, alias) ?: return@let
+                    val key = KeyChain.getPrivateKey(context, alias) ?: return@let
+                    logger.fine("Using provider certificate $alias for authentication (chain length: ${certs.size})")
+
+                    // create Android KeyStore (performs key operations without revealing secret data to DAVx5)
+                    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 }
+                    }
+
+                    // HTTP/2 doesn't support client certificates (yet)
+                    // see https://tools.ietf.org/html/draft-ietf-httpbis-http2-secondary-certs-04
+                    orig.protocols(listOf(Protocol.HTTP_1_1))
+                } catch (e: Exception) {
+                    logger.log(Level.SEVERE, "Couldn't set up provider certificate authentication", e)
+                }
+            }
+
+            val sslContext = SSLContext.getInstance("TLS")
+            sslContext.init(
+                    if (keyManager != null) arrayOf(keyManager) else null,
+                    arrayOf(trustManager),
+                    null)
+            orig.sslSocketFactory(sslContext.socketFactory, trustManager)
+            orig.hostnameVerifier(hostnameVerifier)
+
+            return HttpClient(orig.build(), certManager)
+        }
+
+    }
+
+
+    private object UserAgentInterceptor: Interceptor {
+        // use Locale.US because numbers may be encoded as non-ASCII characters in other locales
+        private val userAgentDateFormat = SimpleDateFormat("yyyy/MM/dd", Locale.US)
+        private val userAgentDate = userAgentDateFormat.format(Date(BuildConfig.buildTime))
+        private val userAgent = "${BuildConfig.userAgent}/${BuildConfig.VERSION_NAME} ($userAgentDate; dav4jvm; " +
+                "okhttp/${BuildConfig.okhttpVersion}) Android/${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.java

@@ -1,19 +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;
-
-public class InvalidAccountException extends Exception {
-
-    public InvalidAccountException(Account account) {
-        super("Invalid account: " + account);
-    }
-
-}

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

@@ -1,69 +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;
-
-import org.apache.commons.collections4.MapIterator;
-import org.apache.commons.collections4.keyvalue.MultiKey;
-import org.apache.commons.collections4.map.HashedMap;
-import org.apache.commons.collections4.map.MultiKeyMap;
-
-import java.util.LinkedList;
-import java.util.List;
-
-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 {
-
-    /**
-     * 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!
-     */
-    protected final MultiKeyMap<String, Cookie> storage = MultiKeyMap.multiKeyMap(new HashedMap<MultiKey<? extends String>, Cookie>());
-
-    @Override
-    public void saveFromResponse(HttpUrl url, List<Cookie> cookies) {
-        synchronized(storage) {
-            for (Cookie cookie : cookies)
-                storage.put(cookie.name(), cookie.domain(), cookie.path(), cookie);
-        }
-    }
-
-    @Override
-    public List<Cookie> loadForRequest(HttpUrl url) {
-        List<Cookie> cookies = new LinkedList<>();
-
-        synchronized(storage) {
-            MapIterator<MultiKey<? extends String>, Cookie> iter = storage.mapIterator();
-            while (iter.hasNext()) {
-                iter.next();
-                Cookie cookie = iter.getValue();
-
-                // remove expired cookies
-                if (cookie.expiresAt() <= System.currentTimeMillis()) {
-                    iter.remove();
-                    continue;
-                }
-
-                // add applicable cookies
-                if (cookie.matches(url))
-                    cookies.add(cookie);
-            }
-        }
-
-        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!
+     */
+    private 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 +1,58 @@
+/*
+ * 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.content.BroadcastReceiver
+import android.content.ContentResolver
+import android.content.Context
+import android.content.Intent
+import android.os.Bundle
+import androidx.annotation.WorkerThread
+import at.bitfire.davdroid.log.Logger
+import at.bitfire.davdroid.model.AppDatabase
+import at.bitfire.davdroid.model.Service
+import at.bitfire.davdroid.resource.LocalTaskList
+import at.bitfire.ical4android.TaskProvider.ProviderName.OpenTasks
+import kotlin.concurrent.thread
+
+class PackageChangedReceiver: BroadcastReceiver() {
+
+    companion object {
+
+        @WorkerThread
+        fun updateTaskSync(context: Context) {
+            val tasksInstalled = LocalTaskList.tasksProviderAvailable(context)
+            Logger.log.info("Tasks provider available = $tasksInstalled")
+
+            // check all accounts and (de)activate OpenTasks if a CalDAV service is defined
+            val db = AppDatabase.getInstance(context)
+            db.serviceDao().getByType(Service.TYPE_CALDAV).forEach { service ->
+                val account = Account(service.accountName, context.getString(R.string.account_type))
+                if (tasksInstalled) {
+                    if (ContentResolver.getIsSyncable(account, OpenTasks.authority) <= 0) {
+                        ContentResolver.setIsSyncable(account, OpenTasks.authority, 1)
+                        ContentResolver.addPeriodicSync(account, OpenTasks.authority, Bundle(), Constants.DEFAULT_SYNC_INTERVAL)
+                    }
+                } else
+                    ContentResolver.setIsSyncable(account, OpenTasks.authority, 0)
+
+            }
+        }
+
+    }
+
+
+    override fun onReceive(context: Context, intent: Intent) {
+        thread {
+            updateTaskSync(context)
+        }
+    }
+
+}

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

@@ -1,171 +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.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_ECDHE_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.info("Available cipher suites: " + TextUtils.join(", ", availableCiphers));
-                    App.log.info("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 const 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 +1,137 @@
+/*
+ * 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.annotation.SuppressLint
+import android.app.PendingIntent
+import android.content.Context
+import android.content.Intent
+import android.content.SharedPreferences
+import android.util.Log
+import android.widget.Toast
+import androidx.core.app.NotificationCompat
+import androidx.core.app.NotificationManagerCompat
+import androidx.core.content.FileProvider
+import androidx.preference.PreferenceManager
+import at.bitfire.davdroid.R
+import at.bitfire.davdroid.ui.AppSettingsActivity
+import at.bitfire.davdroid.ui.NotificationUtils
+import java.io.File
+import java.io.IOException
+import java.util.logging.FileHandler
+import java.util.logging.Level
+
+@SuppressLint("StaticFieldLeak")    // we'll only keep an app context
+object Logger : SharedPreferences.OnSharedPreferenceChangeListener {
+
+    private const val LOG_TO_FILE = "log_to_file"
+
+    val log: java.util.logging.Logger = java.util.logging.Logger.getLogger("davx5")
+
+    private lateinit var context: Context
+    private lateinit var preferences: SharedPreferences
+
+    fun initialize(someContext: Context) {
+        context = someContext.applicationContext
+        preferences = PreferenceManager.getDefaultSharedPreferences(context)
+        preferences.registerOnSharedPreferenceChangeListener(this)
+
+        reinitialize()
+    }
+
+    override fun onSharedPreferenceChanged(sharedPreferences: SharedPreferences, key: String) {
+        if (key == LOG_TO_FILE) {
+            log.info("Logging settings changed; re-initializing logger")
+            reinitialize()
+        }
+    }
+
+    private fun reinitialize() {
+        val logToFile = preferences.getBoolean(LOG_TO_FILE, 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 = NotificationManagerCompat.from(context)
+        // log to external file according to preferences
+        if (logToFile) {
+            val builder = NotificationUtils.newBuilder(context, NotificationUtils.CHANNEL_DEBUG)
+            builder .setSmallIcon(R.drawable.ic_sd_card_notify)
+                    .setContentTitle(context.getString(R.string.logging_notification_title))
+
+            val logDir = debugDir(context) ?: return
+            val logFile = File(logDir, "davx5-log.txt")
+
+            try {
+                val fileHandler = FileHandler(logFile.toString(), true)
+                fileHandler.formatter = PlainTextFormatter.DEFAULT
+                rootLogger.addHandler(fileHandler)
+
+                val prefIntent = Intent(context, AppSettingsActivity::class.java)
+                prefIntent.putExtra(AppSettingsActivity.EXTRA_SCROLL_TO, LOG_TO_FILE)
+                prefIntent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK)
+
+                builder .setContentText(logDir.path)
+                        .setCategory(NotificationCompat.CATEGORY_STATUS)
+                        .setPriority(NotificationCompat.PRIORITY_HIGH)
+                        .setContentText(context.getString(R.string.logging_notification_text))
+                        .setContentIntent(PendingIntent.getActivity(context, 0, prefIntent, PendingIntent.FLAG_UPDATE_CURRENT))
+                        .setOngoing(true)
+
+                // add "Share" action
+                val logFileUri = FileProvider.getUriForFile(context, context.getString(R.string.authority_debug_provider), logFile)
+                log.fine("Now logging to file: $logFile -> $logFileUri")
+
+                val shareIntent = Intent(Intent.ACTION_SEND)
+                shareIntent.putExtra(Intent.EXTRA_SUBJECT, "DAVx⁵ logs")
+                shareIntent.putExtra(Intent.EXTRA_STREAM, logFileUri)
+                shareIntent.type = "text/plain"
+                shareIntent.addFlags(Intent.FLAG_GRANT_READ_URI_PERMISSION or Intent.FLAG_ACTIVITY_NEW_TASK)
+                val chooserIntent = Intent.createChooser(shareIntent, null)
+                val shareAction = NotificationCompat.Action.Builder(R.drawable.ic_share_notify,
+                        context.getString(R.string.logging_notification_send_log),
+                        PendingIntent.getActivity(context, 0, chooserIntent, PendingIntent.FLAG_UPDATE_CURRENT))
+                builder.addAction(shareAction.build())
+            } catch(e: IOException) {
+                log.log(Level.SEVERE, "Couldn't create log file", e)
+                Toast.makeText(context, context.getString(R.string.logging_couldnt_create_file), Toast.LENGTH_LONG).show()
+            }
+
+            nm.notify(NotificationUtils.NOTIFY_EXTERNAL_FILE_LOGGING, builder.build())
+        } else {
+            nm.cancel(NotificationUtils.NOTIFY_EXTERNAL_FILE_LOGGING)
+
+            // delete old logs
+            debugDir(context)?.deleteRecursively()
+        }
+    }
+
+
+    private fun debugDir(context: Context): File? {
+        val dir = File(context.filesDir, "debug")
+        if (dir.exists() && dir.isDirectory)
+            return dir
+
+        if (dir.mkdir())
+            return dir
+
+        Toast.makeText(context, context.getString(R.string.logging_couldnt_create_file), Toast.LENGTH_LONG).show()
+        return null
+    }
+
+}

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

@@ -1,61 +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 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;
-
-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
-    @SuppressWarnings("ThrowableResultOfMethodCallIgnored")
-    public String format(LogRecord r) {
-        StringBuilder builder = new StringBuilder();
-
-        if (!logcat)
-            builder .append(DateFormatUtils.format(r.getMillis(), "yyyy-MM-dd HH:mm:ss"))
-                    .append(" ").append(r.getThreadID()).append(" ");
-
-        builder.append(String.format("[%s] %s", shortClassName(r.getSourceClassName()), r.getMessage()));
-
-        if (r.getThrown() != null)
-            builder .append("\nEXCEPTION ")
-                    .append(ExceptionUtils.getStackTrace(r.getThrown()));
-
-        if (r.getParameters() != null) {
-            int idx = 1;
-            for (Object param : r.getParameters())
-                builder.append("\n\tPARAMETER #").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 {
+        val LOGCAT = PlainTextFormatter(true)
+        val DEFAULT = PlainTextFormatter(false)
+
+        const 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/AppDatabase.kt

@@ -0,0 +1,224 @@
+package at.bitfire.davdroid.model
+
+import android.content.Context
+import android.database.sqlite.SQLiteException
+import android.database.sqlite.SQLiteQueryBuilder
+import androidx.room.Database
+import androidx.room.Room
+import androidx.room.RoomDatabase
+import androidx.room.TypeConverters
+import androidx.room.migration.Migration
+import androidx.sqlite.db.SupportSQLiteDatabase
+import at.bitfire.davdroid.log.Logger
+
+@Suppress("ClassName")
+@Database(entities = [
+    Service::class,
+    HomeSet::class,
+    Collection::class
+], version = 7)
+@TypeConverters(Converters::class)
+abstract class AppDatabase: RoomDatabase() {
+
+    abstract fun serviceDao(): ServiceDao
+    abstract fun homeSetDao(): HomeSetDao
+    abstract fun collectionDao(): CollectionDao
+
+    companion object {
+
+        private var INSTANCE: AppDatabase? = null
+
+        @Synchronized
+        fun getInstance(context: Context): AppDatabase {
+            INSTANCE?.let { return it }
+
+            val db = Room.databaseBuilder(context.applicationContext, AppDatabase::class.java, "services.db")
+                    .addMigrations(
+                            Migration1_2,
+                            Migration2_3,
+                            Migration3_4,
+                            Migration4_5,
+                            Migration5_6,
+                            Migration6_7
+                    )
+                    .fallbackToDestructiveMigration()   // as a last fallback, recreate database instead of crashing
+                    .build()
+            INSTANCE = db
+
+            return db
+        }
+
+    }
+
+    fun dump(sb: StringBuilder) {
+        val db = openHelper.readableDatabase
+        db.beginTransactionNonExclusive()
+
+        // iterate through all tables
+        db.query(SQLiteQueryBuilder.buildQueryString(false, "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("SELECT * FROM $table").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()
+        }
+    }
+
+
+    // migrations
+
+    object Migration6_7: Migration(6, 7) {
+        override fun migrate(db: SupportSQLiteDatabase) {
+            db.execSQL("ALTER TABLE homeset ADD COLUMN privBind INTEGER NOT NULL DEFAULT 1")
+            db.execSQL("ALTER TABLE homeset ADD COLUMN displayName TEXT DEFAULT NULL")
+        }
+    }
+
+    object Migration5_6: Migration(5, 6) {
+        override fun migrate(db: SupportSQLiteDatabase) {
+            val sql = arrayOf(
+                    // migrate "services" to "service": rename columns, make id NOT NULL
+                    "CREATE TABLE service(" +
+                            "id INTEGER NOT NULL PRIMARY KEY AUTOINCREMENT," +
+                            "accountName TEXT NOT NULL," +
+                            "type TEXT NOT NULL," +
+                            "principal TEXT DEFAULT NULL" +
+                            ")",
+                    "CREATE UNIQUE INDEX index_service_accountName_type ON service(accountName, type)",
+                    "INSERT INTO service(id, accountName, type, principal) SELECT _id, accountName, service, principal FROM services",
+                    "DROP TABLE services",
+
+                    // migrate "homesets" to "homeset": rename columns, make id NOT NULL
+                    "CREATE TABLE homeset(" +
+                            "id INTEGER NOT NULL PRIMARY KEY AUTOINCREMENT," +
+                            "serviceId INTEGER NOT NULL," +
+                            "url TEXT NOT NULL," +
+                            "FOREIGN KEY (serviceId) REFERENCES service(id) ON DELETE CASCADE" +
+                    ")",
+                    "CREATE UNIQUE INDEX index_homeset_serviceId_url ON homeset(serviceId, url)",
+                    "INSERT INTO homeset(id, serviceId, url) SELECT _id, serviceID, url FROM homesets",
+                    "DROP TABLE homesets",
+
+                    // migrate "collections" to "collection": rename columns, make id NOT NULL
+                    "CREATE TABLE collection(" +
+                            "id INTEGER NOT NULL PRIMARY KEY AUTOINCREMENT," +
+                            "serviceId INTEGER NOT NULL," +
+                            "type TEXT NOT NULL," +
+                            "url TEXT NOT NULL," +
+                            "privWriteContent INTEGER NOT NULL DEFAULT 1," +
+                            "privUnbind INTEGER NOT NULL DEFAULT 1," +
+                            "forceReadOnly INTEGER NOT NULL DEFAULT 0," +
+                            "displayName TEXT DEFAULT NULL," +
+                            "description TEXT DEFAULT NULL," +
+                            "color INTEGER DEFAULT NULL," +
+                            "timezone TEXT DEFAULT NULL," +
+                            "supportsVEVENT INTEGER DEFAULT NULL," +
+                            "supportsVTODO INTEGER DEFAULT NULL," +
+                            "supportsVJOURNAL INTEGER DEFAULT NULL," +
+                            "source TEXT DEFAULT NULL," +
+                            "sync INTEGER NOT NULL DEFAULT 0," +
+                            "FOREIGN KEY (serviceId) REFERENCES service(id) ON DELETE CASCADE" +
+                    ")",
+                    "CREATE INDEX index_collection_serviceId_type ON collection(serviceId,type)",
+                    "INSERT INTO collection(id, serviceId, type, url, privWriteContent, privUnbind, forceReadOnly, displayName, description, color, timezone, supportsVEVENT, supportsVTODO, source, sync) " +
+                            "SELECT _id, serviceID, type, url, privWriteContent, privUnbind, forceReadOnly, displayName, description, color, timezone, supportsVEVENT, supportsVTODO, source, sync FROM collections",
+                    "DROP TABLE collections"
+            )
+            sql.forEach { db.execSQL(it) }
+        }
+    }
+
+    object Migration4_5: Migration(4, 5) {
+        override fun migrate(db: SupportSQLiteDatabase) {
+            db.execSQL("ALTER TABLE collections ADD COLUMN privWriteContent INTEGER DEFAULT 0 NOT NULL")
+            db.execSQL("UPDATE collections SET privWriteContent=NOT readOnly")
+
+            db.execSQL("ALTER TABLE collections ADD COLUMN privUnbind INTEGER DEFAULT 0 NOT NULL")
+            db.execSQL("UPDATE collections SET privUnbind=NOT readOnly")
+
+            // there's no DROP COLUMN in SQLite, so just keep the "readOnly" column
+        }
+    }
+
+    object Migration3_4: Migration(3, 4) {
+        override fun migrate(db: SupportSQLiteDatabase) {
+            db.execSQL("ALTER TABLE collections ADD COLUMN forceReadOnly INTEGER DEFAULT 0 NOT NULL")
+        }
+    }
+
+    object Migration2_3: Migration(2, 3) {
+        override fun migrate(db: SupportSQLiteDatabase) {
+            // We don't have access to the context in a Room migration now, so
+            // we will just drop those settings from old DAVx5 versions.
+            Logger.log.warning("Dropping settings distrustSystemCerts and overrideProxy*")
+
+            /*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()
+            }*/
+        }
+    }
+
+    object Migration1_2: Migration(1, 2) {
+        override fun migrate(db: SupportSQLiteDatabase) {
+            db.execSQL("ALTER TABLE collections ADD COLUMN type TEXT NOT NULL DEFAULT ''")
+            db.execSQL("ALTER TABLE collections ADD COLUMN source TEXT DEFAULT NULL")
+            db.execSQL("UPDATE collections SET type=(" +
+                        "SELECT CASE service WHEN ? THEN ? ELSE ? END " +
+                        "FROM services WHERE _id=collections.serviceID" +
+                    ")",
+                    arrayOf("caldav", "CALENDAR", "ADDRESS_BOOK"))
+        }
+    }
+
+}

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

@@ -0,0 +1,160 @@
+package at.bitfire.davdroid.model
+
+import androidx.room.*
+import at.bitfire.dav4jvm.Response
+import at.bitfire.dav4jvm.UrlUtils
+import at.bitfire.dav4jvm.property.*
+import at.bitfire.davdroid.DavUtils
+import okhttp3.HttpUrl
+import okhttp3.HttpUrl.Companion.toHttpUrlOrNull
+
+@Entity(tableName = "collection",
+        foreignKeys = [
+            ForeignKey(entity = Service::class, parentColumns = arrayOf("id"), childColumns = arrayOf("serviceId"), onDelete = ForeignKey.CASCADE)
+        ],
+        indices = [
+            Index("serviceId","type")
+        ]
+)
+data class Collection(
+    @PrimaryKey(autoGenerate = true)
+    override var id: Long = 0,
+
+    var serviceId: Long = 0,
+
+    var type: String,
+    var url: HttpUrl,
+
+    var privWriteContent: Boolean = true,
+    var privUnbind: Boolean = true,
+    var forceReadOnly: Boolean = false,
+
+    var displayName: String? = null,
+    var description: String? = null,
+
+    // CalDAV only
+    var color: Int? = null,
+
+    /** timezone definition (full VTIMEZONE) - not a TZID! **/
+    var timezone: String? = null,
+
+    /** whether the collection supports VEVENT; in case of calendars: null means true */
+    var supportsVEVENT: Boolean? = null,
+
+    /** whether the collection supports VTODO; in case of calendars: null means true */
+    var supportsVTODO: Boolean? = null,
+
+    /** whether the collection supports VJOURNAL; in case of calendars: null means true */
+    var supportsVJOURNAL: Boolean? = null,
+
+    /** Webcal subscription source URL */
+    var source: HttpUrl? = null,
+
+    /** whether this collection has been selected for synchronization */
+    var sync: Boolean = false
+
+): IdEntity() {
+
+    companion object {
+
+        const val TYPE_ADDRESSBOOK = "ADDRESS_BOOK"
+        const val TYPE_CALENDAR = "CALENDAR"
+        const val TYPE_WEBCAL = "WEBCAL"
+
+        /**
+         * Generates a collection entity from a WebDAV response.
+         * @param dav WebDAV response
+         * @return null if the response doesn't represent a collection
+         */
+        fun fromDavResponse(dav: Response): Collection? {
+            val url = UrlUtils.withTrailingSlash(dav.href)
+            val type: String = dav[ResourceType::class.java]?.let { resourceType ->
+                when {
+                    resourceType.types.contains(ResourceType.ADDRESSBOOK) -> TYPE_ADDRESSBOOK
+                    resourceType.types.contains(ResourceType.CALENDAR)    -> TYPE_CALENDAR
+                    resourceType.types.contains(ResourceType.SUBSCRIBED)  -> TYPE_WEBCAL
+                    else -> null
+                }
+            } ?: return null
+
+            var privWriteContent = true
+            var privUnbind = true
+            dav[CurrentUserPrivilegeSet::class.java]?.let { privilegeSet ->
+                privWriteContent = privilegeSet.mayWriteContent
+                privUnbind = privilegeSet.mayUnbind
+            }
+
+            var displayName: String? = null
+            dav[DisplayName::class.java]?.let {
+                if (!it.displayName.isNullOrEmpty())
+                    displayName = it.displayName
+            }
+
+            var description: String? = null
+            var color: Int? = null
+            var timezone: String? = null
+            var supportsVEVENT: Boolean? = null
+            var supportsVTODO: Boolean? = null
+            var supportsVJOURNAL: Boolean? = null
+            var source: HttpUrl? = null
+            when (type) {
+                TYPE_ADDRESSBOOK -> {
+                    dav[AddressbookDescription::class.java]?.let { description = it.description }
+                }
+                TYPE_CALENDAR, TYPE_WEBCAL -> {
+                    dav[CalendarDescription::class.java]?.let { description = it.description }
+                    dav[CalendarColor::class.java]?.let { color = it.color }
+                    dav[CalendarTimezone::class.java]?.let { timezone = it.vTimeZone }
+
+                    if (type == TYPE_CALENDAR) {
+                        supportsVEVENT = true
+                        supportsVTODO = true
+                        supportsVJOURNAL = true
+                        dav[SupportedCalendarComponentSet::class.java]?.let {
+                            supportsVEVENT = it.supportsEvents
+                            supportsVTODO = it.supportsTasks
+                            supportsVJOURNAL = it.supportsJournal
+                        }
+                    } else { // Type.WEBCAL
+                        dav[Source::class.java]?.let {
+                            source = it.hrefs.firstOrNull()?.let { rawHref ->
+                                val href = rawHref
+                                        .replace("^webcal://".toRegex(), "http://")
+                                        .replace("^webcals://".toRegex(), "https://")
+                                href.toHttpUrlOrNull()
+                            }
+                        }
+                        supportsVEVENT = true
+                    }
+                }
+            }
+
+            return Collection(
+                    type = type,
+                    url = url,
+                    privWriteContent = privWriteContent,
+                    privUnbind = privUnbind,
+                    displayName = displayName,
+                    description = description,
+                    color = color,
+                    timezone = timezone,
+                    supportsVEVENT = supportsVEVENT,
+                    supportsVTODO = supportsVTODO,
+                    supportsVJOURNAL = supportsVJOURNAL,
+                    source = source
+            )
+        }
+
+    }
+
+
+    // non-persistent properties
+    @Ignore
+    var confirmed: Boolean = false
+
+
+    // calculated properties
+    fun title() = displayName ?: DavUtils.lastSegmentOfUrl(url)
+    fun readOnly() = forceReadOnly || !privWriteContent
+
+}

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

@@ -0,0 +1,43 @@
+package at.bitfire.davdroid.model
+
+import androidx.lifecycle.LiveData
+import androidx.paging.DataSource
+import androidx.room.Dao
+import androidx.room.Insert
+import androidx.room.OnConflictStrategy
+import androidx.room.Query
+
+@Dao
+interface CollectionDao: SyncableDao<Collection> {
+
+    @Query("SELECT * FROM collection WHERE id=:id")
+    fun get(id: Long): Collection?
+
+    @Query("SELECT * FROM collection WHERE serviceId=:serviceId")
+    fun getByService(serviceId: Long): List<Collection>
+
+    @Query("SELECT * FROM collection WHERE serviceId=:serviceId AND type=:type")
+    fun getByServiceAndType(serviceId: Long, type: String): List<Collection>
+
+    @Query("SELECT * FROM collection WHERE serviceId=:serviceId AND type=:type ORDER BY displayName, url")
+    fun pageByServiceAndType(serviceId: Long, type: String): DataSource.Factory<Int, Collection>
+
+    @Query("SELECT * FROM collection WHERE serviceId=:serviceId AND sync ORDER BY displayName, url")
+    fun getByServiceAndSync(serviceId: Long): List<Collection>
+
+    @Query("SELECT COUNT(*) FROM collection WHERE serviceId=:serviceId AND sync")
+    fun observeHasSyncByService(serviceId: Long): LiveData<Boolean>
+
+    @Query("SELECT * FROM collection WHERE serviceId=:serviceId AND supportsVEVENT AND sync ORDER BY displayName, url")
+    fun getSyncCalendars(serviceId: Long): List<Collection>
+
+    @Query("SELECT * FROM collection WHERE serviceId=:serviceId AND supportsVTODO AND sync ORDER BY displayName, url")
+    fun getSyncTaskLists(serviceId: Long): List<Collection>
+
+    @Insert(onConflict = OnConflictStrategy.REPLACE)
+    fun insertOrReplace(collection: Collection)
+
+    @Insert
+    fun insert(collection: Collection)
+
+}

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

@@ -1,163 +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 org.apache.commons.lang3.StringUtils;
-
-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;
-        }
-
-        info.readOnly = false;
-        CurrentUserPrivilegeSet privilegeSet = (CurrentUserPrivilegeSet)dav.properties.get(CurrentUserPrivilegeSet.NAME);
-        if (privilegeSet != null)
-            info.readOnly = !privilegeSet.mayWriteContent;
-
-        DisplayName displayName = (DisplayName)dav.properties.get(DisplayName.NAME);
-        if (displayName != null && !StringUtils.isEmpty(displayName.displayName))
-            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.readOnly = values.getAsInteger(Collections.READ_ONLY) != 0;
-        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 = getAsBooleanOrNull(values, Collections.SUPPORTS_VEVENT);
-        info.supportsVTODO = getAsBooleanOrNull(values, Collections.SUPPORTS_VTODO);
-
-        info.selected = values.getAsInteger(Collections.SYNC) != 0;
-        return info;
-    }
-
-    public ContentValues toDB() {
-        ContentValues values = new ContentValues();
-        // Collections.SERVICE_ID is never changed
-
-        values.put(Collections.URL, url);
-        values.put(Collections.READ_ONLY, readOnly ? 1 : 0);
-        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 getAsBooleanOrNull(ContentValues values, String field) {
-        Integer i = values.getAsInteger(field);
-        return (i == null) ? null : (i != 0);
-    }
-
-}

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

@@ -0,0 +1,17 @@
+package at.bitfire.davdroid.model
+
+import androidx.room.TypeConverter
+import okhttp3.HttpUrl
+import okhttp3.HttpUrl.Companion.toHttpUrlOrNull
+
+class Converters {
+
+    @TypeConverter
+    fun httpUrlToString(url: HttpUrl?) =
+            url?.toString()
+
+    @TypeConverter
+    fun stringToHttpUrl(url: String?): HttpUrl? =
+            url?.let { it.toHttpUrlOrNull() }
+
+}

app/src/main/java/at/bitfire/davdroid/model/Credentials.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.model
+
+class Credentials(
+        val userName: String? = null,
+        val password: String? = null,
+        val certificateAlias: String? = null
+) {
+
+    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() =
+            "Credentials(type=$type, userName=$userName, certificateAlias=$certificateAlias)"
+
+}

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

@@ -0,0 +1,41 @@
+package at.bitfire.davdroid.model
+
+import at.bitfire.davdroid.log.Logger
+import java.util.logging.Level
+
+class DaoTools<T: IdEntity>(dao: SyncableDao<T>): SyncableDao<T> by dao {
+
+    /**
+     * Synchronizes a list of "old" elements with a list of "new" elements so that the list
+     * only contain equal elements.
+     *
+     * @param allOld      list of old elements
+     * @param allNew      map of new elements (stored in key map)
+     * @param selectKey   generates a unique key from the element (will be called on old elements)
+     * @param prepareNew  prepares new elements (can be used to take over properties of old elements)
+     */
+    fun <K> syncAll(allOld: List<T>, allNew: Map<K,T>, selectKey: (T) -> K, prepareNew: (new: T, old: T) -> Unit = { _, _ -> }) {
+        Logger.log.log(Level.FINE, "Syncing tables", arrayOf(allOld, allNew))
+        val remainingNew = allNew.toMutableMap()
+        allOld.forEach { old ->
+            val key = selectKey(old)
+            val matchingNew = remainingNew[key]
+            if (matchingNew != null) {
+                // keep this old item, but maybe update it
+                matchingNew.id = old.id     // identity is proven by key
+                prepareNew(matchingNew, old)
+
+                if (matchingNew != old)
+                    update(matchingNew)
+
+                // remove from remainingNew
+                remainingNew -= key
+            } else {
+                // this old item is not present anymore, delete it
+                delete(old)
+            }
+        }
+        insert(remainingNew.values.toList())
+    }
+
+}

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

@@ -0,0 +1,28 @@
+package at.bitfire.davdroid.model
+
+import androidx.room.Entity
+import androidx.room.ForeignKey
+import androidx.room.Index
+import androidx.room.PrimaryKey
+import okhttp3.HttpUrl
+
+@Entity(tableName = "homeset",
+        foreignKeys = [
+            ForeignKey(entity = Service::class, parentColumns = arrayOf("id"), childColumns = arrayOf("serviceId"), onDelete = ForeignKey.CASCADE)
+        ],
+        indices = [
+            // index by service; no duplicate URLs per service
+            Index("serviceId", "url", unique = true)
+        ]
+)
+data class HomeSet(
+    @PrimaryKey(autoGenerate = true)
+    override var id: Long,
+
+    var serviceId: Long,
+    var url: HttpUrl,
+
+    var privBind: Boolean = true,
+
+    var displayName: String? = null
+): IdEntity()

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

@@ -0,0 +1,21 @@
+package at.bitfire.davdroid.model
+
+import androidx.room.Dao
+import androidx.room.Insert
+import androidx.room.OnConflictStrategy
+import androidx.room.Query
+
+@Dao
+interface HomeSetDao: SyncableDao<HomeSet> {
+
+    @Query("SELECT * FROM homeset WHERE serviceId=:serviceId")
+    fun getByService(serviceId: Long): List<HomeSet>
+
+    @Query("SELECT * FROM homeset WHERE serviceId=:serviceId AND privBind")
+    fun getBindableByService(serviceId: Long): List<HomeSet>
+
+    @Insert(onConflict = OnConflictStrategy.REPLACE)
+    fun insertOrReplace(homeSet: HomeSet): Long
+
+
+}

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

@@ -0,0 +1,5 @@
+package at.bitfire.davdroid.model
+
+abstract class IdEntity {
+    abstract var id: Long
+}

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

@@ -0,0 +1,28 @@
+package at.bitfire.davdroid.model
+
+import androidx.room.Entity
+import androidx.room.Index
+import androidx.room.PrimaryKey
+import okhttp3.HttpUrl
+
+@Entity(tableName = "service",
+        indices = [
+            // only one service per type and account
+            Index("accountName", "type", unique = true)
+        ])
+data class Service(
+    @PrimaryKey(autoGenerate = true)
+    var id: Long,
+
+    var accountName: String,
+    var type: String,
+
+    var principal: HttpUrl?
+) {
+
+    companion object {
+        const val TYPE_CALDAV = "caldav"
+        const val TYPE_CARDDAV = "carddav"
+    }
+
+}

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

@@ -1,186 +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 Settings {
-        public static final String
-                _TABLE = "settings",
-                NAME = "setting",
-                VALUE = "value";
-    }
-
-    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",
-                READ_ONLY = "readOnly",
-                DISPLAY_NAME = "displayName",
-                DESCRIPTION = "description",
-                COLOR = "color",
-                TIME_ZONE = "timezone",
-                SUPPORTS_VEVENT = "supportsVEVENT",
-                SUPPORTS_VTODO = "supportsVTODO",
-                SYNC = "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);
-
-            if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.JELLY_BEAN)
-                setWriteAheadLoggingEnabled(true);
-        }
-
-        @Override
-        public void onOpen(SQLiteDatabase db) {
-            if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.JELLY_BEAN)
-                db.setForeignKeyConstraintsEnabled(true);
-            else {
-                if (!db.enableWriteAheadLogging())
-                    App.log.warning("Couldn't enable write-ahead logging");
-
-                db.execSQL("PRAGMA foreign_keys=ON;");
-            }
-        }
-
-        @Override
-        public void onCreate(SQLiteDatabase db) {
-            App.log.info("Creating database " + db.getPath());
-
-            db.execSQL("CREATE TABLE " + Settings._TABLE + "(" +
-                    Settings.NAME + " TEXT NOT NULL," +
-                    Settings.VALUE + " TEXT NOT NULL" +
-            ")");
-            db.execSQL("CREATE UNIQUE INDEX settings_name ON " + Settings._TABLE + " (" + Settings.NAME + ")");
-
-            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.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.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(table).append("\n");
-                @Cleanup Cursor cursor = db.query(table, null, null, null, null, null, null);
-
-                // print columns
-                int cols = cursor.getColumnCount();
-                sb.append("\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| ");
-                    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");
-                }
-                sb.append("----------\n");
-            }
-            db.endTransaction();
-        }
-    }
-
-}

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

@@ -0,0 +1,35 @@
+package at.bitfire.davdroid.model
+
+import androidx.room.Dao
+import androidx.room.Insert
+import androidx.room.OnConflictStrategy
+import androidx.room.Query
+
+@Dao
+interface ServiceDao {
+
+    @Query("SELECT * FROM service WHERE accountName=:accountName AND type=:type")
+    fun getByAccountAndType(accountName: String, type: String): Service?
+
+    @Query("SELECT id FROM service WHERE accountName=:accountName AND type=:type")
+    fun getIdByAccountAndType(accountName: String, type: String): Long?
+
+    @Query("SELECT * FROM service WHERE id=:id")
+    fun get(id: Long): Service?
+
+    @Query("SELECT * FROM service WHERE type=:type")
+    fun getByType(type: String): List<Service>
+
+    @Insert(onConflict = OnConflictStrategy.REPLACE)
+    fun insertOrReplace(service: Service): Long
+
+    @Query("DELETE FROM service")
+    fun deleteAll()
+
+    @Query("DELETE FROM service WHERE accountName NOT IN (:accountNames)")
+    fun deleteExceptAccounts(accountNames: Array<String>)
+
+    @Query("UPDATE service SET accountName=:newName WHERE accountName=:oldName")
+    fun renameAccount(oldName: String, newName: String)
+
+}

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

@@ -1,45 +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 android.database.Cursor;
-import android.database.sqlite.SQLiteDatabase;
-
-import lombok.Cleanup;
-
-public class Settings {
-
-    final SQLiteDatabase db;
-
-    public Settings(SQLiteDatabase db) {
-        this.db = db;
-    }
-
-    public boolean getBoolean(String name, boolean defaultValue) {
-        @Cleanup Cursor cursor = db.query(ServiceDB.Settings._TABLE, new String[] { ServiceDB.Settings.VALUE },
-                ServiceDB.Settings.NAME + "=?", new String[] { name }, null, null, null);
-        if (cursor.moveToNext())
-            return cursor.getInt(0) != 0;
-        else
-            return defaultValue;
-    }
-
-    public void putBoolean(String name, boolean value) {
-        ContentValues values = new ContentValues(2);
-        values.put(ServiceDB.Settings.NAME, name);
-        values.put(ServiceDB.Settings.VALUE, value ? 1 : 0);
-        db.insertWithOnConflict(ServiceDB.Settings._TABLE, null, values, SQLiteDatabase.CONFLICT_REPLACE);
-    }
-
-    public void remove(String name) {
-        db.delete(ServiceDB.Settings._TABLE, ServiceDB.Settings.NAME + "=?", new String[] { name });
-    }
-
-}

app/src/main/java/at/bitfire/davdroid/model/SyncState.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.model
+
+import at.bitfire.dav4jvm.property.SyncToken
+import org.json.JSONException
+import org.json.JSONObject
+
+data class SyncState(
+        val type: Type,
+        val value: String,
+
+        /**
+         * Whether this sync state occurred during an initial sync as described
+         * in RFC 6578, which means the initial sync is not complete yet.
+         */
+        var initialSync: Boolean? = null
+) {
+
+    companion object {
+
+        private const val KEY_TYPE = "type"
+        private const val KEY_VALUE = "value"
+        private const val KEY_INITIAL_SYNC = "initialSync"
+
+        fun fromString(s: String?): SyncState? {
+            if (s == null)
+                return null
+
+            return try {
+                val json = JSONObject(s)
+                SyncState(
+                        Type.valueOf(json.getString(KEY_TYPE)),
+                        json.getString(KEY_VALUE),
+                        try { json.getBoolean(KEY_INITIAL_SYNC) } catch(e: JSONException) { null }
+                )
+            } catch (e: JSONException) {
+                null
+            }
+        }
+
+        fun fromSyncToken(token: SyncToken, initialSync: Boolean? = null) =
+                SyncState(Type.SYNC_TOKEN, requireNotNull(token.token), initialSync)
+
+    }
+
+    enum class Type { CTAG, SYNC_TOKEN }
+
+    override fun toString(): String {
+        val json = JSONObject()
+        json.put(KEY_TYPE, type.name)
+        json.put(KEY_VALUE, value)
+        initialSync?.let { json.put(KEY_INITIAL_SYNC, it) }
+        return json.toString()
+    }
+
+}

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

@@ -0,0 +1,18 @@
+package at.bitfire.davdroid.model
+
+import androidx.room.Delete
+import androidx.room.Insert
+import androidx.room.Update
+
+interface SyncableDao<T: IdEntity> {
+
+    @Insert
+    fun insert(items: List<T>)
+
+    @Update
+    fun update(item: T)
+
+    @Delete
+    fun delete(item: T)
+
+}

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

@@ -1,22 +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.provider.ContactsContract.RawContacts;
-
-public class UnknownProperties {
-
-    public static final String CONTENT_ITEM_TYPE = "x.davdroid/unknown-properties";
-
-    public static final String
-            MIMETYPE = RawContacts.Data.MIMETYPE,
-            RAW_CONTACT_ID = RawContacts.Data.RAW_CONTACT_ID,
-            UNKNOWN_PROPERTIES = RawContacts.Data.DATA1;
-
-}

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

@@ -0,0 +1,21 @@
+/*
+ * 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 {
+
+    const val CONTENT_ITEM_TYPE = "x.davdroid/unknown-properties"
+
+    const val MIMETYPE = RawContacts.Data.MIMETYPE
+    const val RAW_CONTACT_ID = RawContacts.Data.RAW_CONTACT_ID
+    const val UNKNOWN_PROPERTIES = RawContacts.Data.DATA1
+
+}

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

@@ -0,0 +1,17 @@
+/*
+ * 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.vcard4android.Contact
+
+interface LocalAddress: LocalResource<Contact> {
+
+    fun resetDeleted()
+
+}

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

@@ -1,229 +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.net.Uri;
-import android.os.Bundle;
-import android.os.Parcel;
-import android.os.RemoteException;
-import android.provider.ContactsContract.Groups;
-import android.provider.ContactsContract.RawContacts;
-import android.support.annotation.NonNull;
-
-import java.io.FileNotFoundException;
-import java.util.Collections;
-import java.util.LinkedList;
-import java.util.List;
-
-import at.bitfire.vcard4android.AndroidAddressBook;
-import at.bitfire.vcard4android.AndroidContact;
-import at.bitfire.vcard4android.AndroidGroup;
-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();
-
-    /**
-     * Whether contact groups (LocalGroup resources) are included in query results for
-     * {@link #getAll()}, {@link #getDeleted()}, {@link #getDirty()} and
-     * {@link #getWithoutFileName()}.
-     */
-    public boolean includeGroups = true;
-
-
-    public LocalAddressBook(Account account, ContentProviderClient provider) {
-        super(account, provider, LocalGroup.Factory.INSTANCE, LocalContact.Factory.INSTANCE);
-    }
-
-    public LocalContact findContactByUID(String uid) throws ContactsStorageException, FileNotFoundException {
-        LocalContact[] contacts = (LocalContact[])queryContacts(LocalContact.COLUMN_UID + "=?", new String[] { uid });
-        if (contacts.length == 0)
-            throw new FileNotFoundException();
-        return contacts[0];
-    }
-
-    @Override
-    public LocalResource[] getAll() throws ContactsStorageException {
-        List<LocalResource> all = new LinkedList<>();
-        Collections.addAll(all, (LocalResource[])queryContacts(null, null));
-        if (includeGroups)
-            Collections.addAll(all, (LocalResource[])queryGroups(null, null));
-        return all.toArray(new LocalResource[all.size()]);
-    }
-
-    /**
-     * Returns an array of local contacts/groups which have been deleted locally. (DELETED != 0).
-     */
-    @Override
-    public LocalResource[] getDeleted() throws ContactsStorageException {
-        List<LocalResource> deleted = new LinkedList<>();
-        Collections.addAll(deleted, getDeletedContacts());
-        if (includeGroups)
-            Collections.addAll(deleted, getDeletedGroups());
-        return deleted.toArray(new LocalResource[deleted.size()]);
-    }
-
-    /**
-     * Returns an array of local contacts/groups which have been changed locally (DIRTY != 0).
-     */
-    @Override
-    public LocalResource[] getDirty() throws ContactsStorageException {
-        List<LocalResource> dirty = new LinkedList<>();
-        Collections.addAll(dirty, getDirtyContacts());
-        if (includeGroups)
-            Collections.addAll(dirty, getDirtyGroups());
-        return dirty.toArray(new LocalResource[dirty.size()]);
-    }
-
-    /**
-     * Returns an array of local contacts which don't have a file name yet.
-     */
-    @Override
-    public LocalResource[] getWithoutFileName() throws ContactsStorageException {
-        List<LocalResource> nameless = new LinkedList<>();
-        Collections.addAll(nameless, (LocalContact[])queryContacts(AndroidContact.COLUMN_FILENAME + " IS NULL", null));
-        if (includeGroups)
-            Collections.addAll(nameless, (LocalGroup[])queryGroups(AndroidGroup.COLUMN_FILENAME + " IS NULL", null));
-        return nameless.toArray(new LocalResource[nameless.size()]);
-    }
-
-    public void deleteAll() throws ContactsStorageException {
-        try {
-            provider.delete(syncAdapterURI(RawContacts.CONTENT_URI), null, null);
-            provider.delete(syncAdapterURI(Groups.CONTENT_URI), null, null);
-        } catch(RemoteException e) {
-            throw new ContactsStorageException("Couldn't delete all local contacts and groups", e);
-        }
-    }
-
-
-    public LocalContact[] getDeletedContacts() throws ContactsStorageException {
-        return (LocalContact[])queryContacts(RawContacts.DELETED + "!= 0", null);
-    }
-
-    public LocalContact[] getDirtyContacts() throws ContactsStorageException {
-        return (LocalContact[])queryContacts(RawContacts.DIRTY + "!= 0", null);
-    }
-
-    public LocalGroup[] getDeletedGroups() throws ContactsStorageException {
-        return (LocalGroup[])queryGroups(Groups.DELETED + "!= 0", null);
-    }
-
-    public LocalGroup[] getDirtyGroups() throws ContactsStorageException {
-        return (LocalGroup[])queryGroups(Groups.DIRTY + "!= 0", null);
-    }
-
-
-    /**
-     * 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
-     */
-    public long findOrCreateGroup(@NonNull String title) throws ContactsStorageException {
-        try {
-            @Cleanup Cursor cursor = provider.query(syncAdapterURI(Groups.CONTENT_URI),
-                    new String[] { Groups._ID  },
-                    Groups.TITLE + "=?", new String[] { title },
-                    null);
-            if (cursor != null && cursor.moveToNext())
-                return cursor.getLong(0);
-
-            ContentValues values = new ContentValues();
-            values.put(Groups.TITLE, title);
-            Uri uri = provider.insert(syncAdapterURI(Groups.CONTENT_URI), values);
-            return ContentUris.parseId(uri);
-        } catch(RemoteException e) {
-            throw new ContactsStorageException("Couldn't find local contact group", e);
-        }
-    }
-
-    public void removeEmptyGroups() throws ContactsStorageException {
-        // find groups without members
-        /** should be done using {@link Groups.SUMMARY_COUNT}, but it's not implemented in Android yet */
-        for (LocalGroup group : (LocalGroup[])queryGroups(null, null))
-            if (group.getMembers().length == 0)
-                group.delete();
-    }
-
-    public void removeGroups() throws ContactsStorageException {
-        try {
-            provider.delete(syncAdapterURI(Groups.CONTENT_URI), null, null);
-        } catch(RemoteException e) {
-            throw new ContactsStorageException("Couldn't remove all 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 +1,380 @@
+/*
+ * 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.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.Collection
+import at.bitfire.davdroid.model.SyncState
+import at.bitfire.vcard4android.*
+import java.io.ByteArrayOutputStream
+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, DAVx5 creates a "DAVx5
+ * address book" account for every CardDAV address book. These accounts are bound to a
+ * DAVx5 main account.
+ */
+class LocalAddressBook(
+        private val context: Context,
+        account: Account,
+        provider: ContentProviderClient?
+): AndroidAddressBook<LocalContact, LocalGroup>(account, provider, LocalContact.Factory, LocalGroup.Factory), LocalCollection<LocalAddress> {
+
+    companion object {
+
+        const val USER_DATA_MAIN_ACCOUNT_TYPE = "real_account_type"
+        const val USER_DATA_MAIN_ACCOUNT_NAME = "real_account_name"
+        const val USER_DATA_URL = "url"
+        const val USER_DATA_READ_ONLY = "read_only"
+
+        fun create(context: Context, provider: ContentProviderClient, mainAccount: Account, info: Collection): LocalAddressBook {
+            val accountManager = AccountManager.get(context)
+
+            val account = Account(accountName(mainAccount, info), context.getString(R.string.account_type_address_book))
+            val userData = initialUserData(mainAccount, info.url.toString())
+            Logger.log.log(Level.INFO, "Creating local address book $account", userData)
+            if (!accountManager.addAccountExplicitly(account, null, userData))
+                throw IllegalStateException("Couldn't create address book account")
+
+            if (Build.VERSION.SDK_INT < Build.VERSION_CODES.N)
+                // Android < 7 seems to lose the initial user data sometimes, so set it a second time
+                // https://forums.bitfire.at/post/11644
+                userData.keySet().forEach { key ->
+                    accountManager.setUserData(account, key, userData.getString(key))
+                }
+
+            val addressBook = LocalAddressBook(context, account, provider)
+            ContentResolver.setSyncAutomatically(account, ContactsContract.AUTHORITY, true)
+
+            // initialize Contacts Provider Settings
+            val values = ContentValues(2)
+            values.put(ContactsContract.Settings.SHOULD_SYNC, 1)
+            values.put(ContactsContract.Settings.UNGROUPED_VISIBLE, 1)
+            addressBook.settings = values
+            addressBook.readOnly = !info.privWriteContent || info.forceReadOnly
+
+            return addressBook
+        }
+
+        fun findAll(context: Context, provider: ContentProviderClient?, mainAccount: Account?) = AccountManager.get(context)
+                .getAccountsByType(context.getString(R.string.account_type_address_book))
+                .map { LocalAddressBook(context, it, provider) }
+                .filter { mainAccount == null || it.mainAccount == mainAccount }
+                .toList()
+
+        fun accountName(mainAccount: Account, info: Collection): 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(info.displayName.let {
+                if (it.isNullOrEmpty())
+                    DavUtils.lastSegmentOfUrl(info.url)
+                else
+                    it
+            })
+            sb.append(" (${mainAccount.name} $hash)")
+            return sb.toString()
+        }
+
+        fun initialUserData(mainAccount: Account, url: String): Bundle {
+            val bundle = Bundle(3)
+            bundle.putString(USER_DATA_MAIN_ACCOUNT_NAME, mainAccount.name)
+            bundle.putString(USER_DATA_MAIN_ACCOUNT_TYPE, mainAccount.type)
+            bundle.putString(USER_DATA_URL, url)
+            return bundle
+        }
+
+        fun mainAccount(context: Context, account: Account): Account =
+                if (account.type == context.getString(R.string.account_type_address_book)) {
+                    val manager = AccountManager.get(context)
+                    Account(
+                            manager.getUserData(account, USER_DATA_MAIN_ACCOUNT_NAME),
+                            manager.getUserData(account, USER_DATA_MAIN_ACCOUNT_TYPE)
+                    )
+                } else
+                    account
+
+    }
+
+    override val tag: String
+        get() = "contacts-${account.name}"
+
+    override val title = account.name!!
+
+    /**
+     * Whether contact groups ([LocalGroup]) are included in query results
+     * and are affected by updates/deletes on generic members.
+     *
+     * For instance, if this option is disabled, [findDirty] will find only dirty [LocalContact]s,
+     * but if it is enabled, [findDirty] will find dirty [LocalContact]s and [LocalGroup]s.
+     */
+    var includeGroups = true
+
+    private var _mainAccount: Account? = null
+    var mainAccount: Account
+        get() {
+            _mainAccount?.let { return it }
+
+            AccountManager.get(context).let { accountManager ->
+                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 IllegalStateException("No main account assigned to address book account")
+            }
+        }
+        set(newMainAccount) {
+            AccountManager.get(context).let { accountManager ->
+                accountManager.setUserData(account, USER_DATA_MAIN_ACCOUNT_NAME, newMainAccount.name)
+                accountManager.setUserData(account, USER_DATA_MAIN_ACCOUNT_TYPE, newMainAccount.type)
+            }
+
+            _mainAccount = newMainAccount
+        }
+
+    var url: String
+        get() = AccountManager.get(context).getUserData(account, USER_DATA_URL)
+                ?: throw IllegalStateException("Address book has no URL")
+        set(url) = AccountManager.get(context).setUserData(account, USER_DATA_URL, url)
+
+    override var readOnly: Boolean
+        get() = AccountManager.get(context).getUserData(account, USER_DATA_READ_ONLY) != null
+        set(readOnly) = AccountManager.get(context).setUserData(account, USER_DATA_READ_ONLY, if (readOnly) "1" else null)
+
+    override var lastSyncState: SyncState?
+        get() = syncState?.let { SyncState.fromString(String(it)) }
+        set(state) {
+            syncState = state?.toString()?.toByteArray()
+        }
+
+
+    /* operations on the collection (address book) itself */
+
+    override fun markNotDirty(flags: Int): Int {
+        val values = ContentValues(1)
+        values.put(LocalContact.COLUMN_FLAGS, flags)
+        var number = provider!!.update(rawContactsSyncUri(), values, "${RawContacts.DIRTY}=0", null)
+
+        if (includeGroups) {
+            values.clear()
+            values.put(LocalGroup.COLUMN_FLAGS, flags)
+            number += provider.update(groupsSyncUri(), values, "NOT ${Groups.DIRTY}", null)
+        }
+
+        return number
+    }
+
+    override fun removeNotDirtyMarked(flags: Int): Int {
+        var number = provider!!.delete(rawContactsSyncUri(),
+                "NOT ${RawContacts.DIRTY} AND ${LocalContact.COLUMN_FLAGS}=?", arrayOf(flags.toString()))
+
+        if (includeGroups)
+            number += provider.delete(groupsSyncUri(),
+                    "NOT ${Groups.DIRTY} AND ${LocalGroup.COLUMN_FLAGS}=?", arrayOf(flags.toString()))
+
+        return number
+    }
+
+    fun update(info: Collection) {
+        val newAccountName = accountName(mainAccount, info)
+
+        if (account.name != newAccountName && Build.VERSION.SDK_INT >= 21) {
+            // no need to re-assign contacts to new account, because they will be deleted by contacts provider in any case
+            val accountManager = AccountManager.get(context)
+            val future = accountManager.renameAccount(account, newAccountName, null, null)
+            account = future.result
+        }
+
+        val nowReadOnly = !info.privWriteContent || info.forceReadOnly
+        if (nowReadOnly != readOnly) {
+            Constants.log.info("Address book now read-only = $nowReadOnly, updating contacts")
+
+            // update address book itself
+            readOnly = nowReadOnly
+
+            // update raw contacts
+            val rawContactValues = ContentValues(1)
+            rawContactValues.put(RawContacts.RAW_CONTACT_IS_READ_ONLY, if (nowReadOnly) 1 else 0)
+            provider!!.update(rawContactsSyncUri(), rawContactValues, null, null)
+
+            // update data rows
+            val dataValues = ContentValues(1)
+            dataValues.put(ContactsContract.Data.IS_READ_ONLY, if (nowReadOnly) 1 else 0)
+            provider.update(syncAdapterURI(ContactsContract.Data.CONTENT_URI), dataValues, null, null)
+        }
+
+        // make sure it will still be synchronized when contacts are updated
+        ContentResolver.setSyncAutomatically(account, ContactsContract.AUTHORITY, true)
+    }
+
+    fun delete() {
+        val accountManager = AccountManager.get(context)
+        @Suppress("DEPRECATION")
+        if (Build.VERSION.SDK_INT >= 22)
+            accountManager.removeAccount(account, null, null, null)
+        else
+            accountManager.removeAccount(account, null, null)
+    }
+
+
+    /* operations on members (contacts/groups) */
+
+    override fun findByName(name: String): LocalAddress? {
+        val result = queryContacts("${AndroidContact.COLUMN_FILENAME}=?", arrayOf(name)).firstOrNull()
+        return if (includeGroups)
+            result ?: queryGroups("${AndroidGroup.COLUMN_FILENAME}=?", arrayOf(name)).firstOrNull()
+        else
+            result
+    }
+
+
+    /**
+     * Returns an array of local contacts/groups which have been deleted locally. (DELETED != 0).
+     * @throws RemoteException on content provider errors
+     */
+    override fun findDeleted() =
+            if (includeGroups)
+                findDeletedContacts() + findDeletedGroups()
+            else
+                findDeletedContacts()
+
+    fun findDeletedContacts() = queryContacts(RawContacts.DELETED, null)
+    fun findDeletedGroups() = queryGroups(Groups.DELETED, null)
+
+    /**
+     * Returns an array of local contacts/groups which have been changed locally (DIRTY != 0).
+     * @throws RemoteException on content provider errors
+     */
+    override fun findDirty() =
+            if (includeGroups)
+                findDirtyContacts() + findDirtyGroups()
+            else
+                findDirtyContacts()
+    fun findDirtyContacts() = queryContacts(RawContacts.DIRTY, null)
+    fun findDirtyGroups() = queryGroups(Groups.DIRTY, null)
+
+    override fun findDirtyWithoutNameOrUid() =
+            if (includeGroups)
+                findDirtyContactsWithoutNameOrUid() + findDirtyGroupsWithoutNameOrUid()
+            else
+                findDirtyContactsWithoutNameOrUid()
+    private fun findDirtyContactsWithoutNameOrUid() = queryContacts(
+            "${RawContacts.DIRTY} AND (${AndroidContact.COLUMN_FILENAME} IS NULL OR ${AndroidContact.COLUMN_UID} IS NULL)",
+            null)
+    private fun findDirtyGroupsWithoutNameOrUid() = queryGroups(
+            "${Groups.DIRTY} AND (${AndroidGroup.COLUMN_FILENAME} IS NULL OR ${AndroidGroup.COLUMN_UID} IS NULL)",
+            null)
+
+    override fun forgetETags() {
+        if (includeGroups) {
+            val values = ContentValues(1)
+            values.putNull(AndroidGroup.COLUMN_ETAG)
+            provider!!.update(groupsSyncUri(), values, null, null)
+        }
+        val values = ContentValues(1)
+        values.putNull(AndroidContact.COLUMN_ETAG)
+        provider!!.update(rawContactsSyncUri(), values, null, null)
+    }
+
+
+    /**
+     * 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 RemoteException on content provider errors
+     */
+    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 findDirtyContacts()) {
+            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 $currentHash", contact)
+                reallyDirty++
+            }
+        }
+
+        if (includeGroups)
+            reallyDirty += findDirtyGroups().size
+
+        return reallyDirty
+    }
+
+    fun getByGroupMembership(groupID: Long): List<LocalContact> {
+        val ids = HashSet<Long>()
+        provider!!.query(syncAdapterURI(ContactsContract.Data.CONTENT_URI),
+                arrayOf(RawContacts.Data.RAW_CONTACT_ID),
+                "(${GroupMembership.MIMETYPE}=? AND ${GroupMembership.GROUP_ROW_ID}=?) OR (${CachedGroupMembership.MIMETYPE}=? AND ${CachedGroupMembership.GROUP_ID}=?)",
+                arrayOf(GroupMembership.CONTENT_ITEM_TYPE, groupID.toString(), CachedGroupMembership.CONTENT_ITEM_TYPE, groupID.toString()),
+                null)?.use { cursor ->
+            while (cursor.moveToNext())
+                ids += cursor.getLong(0)
+        }
+
+        return ids.map { findContactByID(it) }
+    }
+
+
+    /* special group operations */
+
+    /**
+     * Finds the first group with the given title. If there is no group with this
+     * title, a new group is created.
+     * @param title title of the group to look for
+     * @return id of the group with given title
+     * @throws RemoteException on content provider errors
+     */
+    fun findOrCreateGroup(title: String): Long {
+        provider!!.query(syncAdapterURI(Groups.CONTENT_URI), arrayOf(Groups._ID),
+                "${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) ?: throw RemoteException("Couldn't create contact group")
+        return ContentUris.parseId(uri)
+    }
+
+    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()
+        }
+    }
+
+}

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

@@ -1,266 +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.annotation.TargetApi;
-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.DavUtils;
-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, 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);
-    }
-
-    public void update(CollectionInfo info, boolean updateColor) throws CalendarStorageException {
-        update(valuesFromCollectionInfo(info, updateColor));
-    }
-
-    @TargetApi(15)
-    private static ContentValues valuesFromCollectionInfo(CollectionInfo info, boolean withColor) {
-        ContentValues values = new ContentValues();
-        values.put(Calendars.NAME, info.url);
-        values.put(Calendars.CALENDAR_DISPLAY_NAME, !TextUtils.isEmpty(info.displayName) ? info.displayName : DavUtils.lastSegmentOfUrl(info.url));
-
-        if (withColor)
-            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);
-        }
-
-        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 +1,255 @@
+/*
+ * 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.accounts.Account
+import android.content.ContentProviderClient
+import android.content.ContentProviderOperation
+import android.content.ContentUris
+import android.content.ContentValues
+import android.net.Uri
+import android.provider.CalendarContract.Calendars
+import android.provider.CalendarContract.Events
+import at.bitfire.davdroid.Constants
+import at.bitfire.davdroid.DavUtils
+import at.bitfire.davdroid.log.Logger
+import at.bitfire.davdroid.model.Collection
+import at.bitfire.davdroid.model.SyncState
+import at.bitfire.ical4android.AndroidCalendar
+import at.bitfire.ical4android.AndroidCalendarFactory
+import at.bitfire.ical4android.BatchOperation
+import at.bitfire.ical4android.DateUtils
+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 {
+
+        private const val COLUMN_SYNC_STATE = Calendars.CAL_SYNC1
+
+        fun create(account: Account, provider: ContentProviderClient, info: Collection): 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: Collection, withColor: Boolean): ContentValues {
+            val values = ContentValues()
+            values.put(Calendars.NAME, info.url.toString())
+            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 ?: Constants.DAVDROID_GREEN_RGBA)
+
+            if (info.privWriteContent && !info.forceReadOnly) {
+                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)
+            } else
+                values.put(Calendars.CALENDAR_ACCESS_LEVEL, Calendars.CAL_ACCESS_READ)
+
+            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)
+                }
+            }
+
+            // add base values for Calendars
+            values.putAll(calendarBaseValues)
+
+            return values
+        }
+    }
+
+    override val tag: String
+        get() = "events-${account.name}-$id"
+
+    override val title: String
+        get() = displayName ?: id.toString()
+
+    override var lastSyncState: SyncState?
+        get() = provider.query(calendarSyncURI(), arrayOf(COLUMN_SYNC_STATE), null, null, null)?.use { cursor ->
+                    if (cursor.moveToNext())
+                        return SyncState.fromString(cursor.getString(0))
+                    else
+                        null
+                }
+        set(state) {
+            val values = ContentValues(1)
+            values.put(COLUMN_SYNC_STATE, state.toString())
+            provider.update(calendarSyncURI(), values, null, null)
+        }
+
+
+    fun update(info: Collection, updateColor: Boolean) =
+            update(valuesFromCollectionInfo(info, updateColor))
+
+
+    override fun findDeleted() =
+            queryEvents("${Events.DELETED} AND ${Events.ORIGINAL_ID} IS NULL", null)
+
+    override fun findDirty(): List<LocalEvent> {
+        val dirty = LinkedList<LocalEvent>()
+
+        // get dirty events which are required to have an increased SEQUENCE value
+        for (localEvent in queryEvents("${Events.DIRTY} AND ${Events.ORIGINAL_ID} IS NULL", null)) {
+            val event = localEvent.event!!
+            val sequence = event.sequence
+            if (event.sequence == null)      // sequence has not been assigned yet (i.e. this event was just locally created)
+                event.sequence = 0
+            else if (localEvent.weAreOrganizer)
+                event.sequence = sequence!! + 1
+            dirty += localEvent
+        }
+
+        return dirty
+    }
+
+    override fun findDirtyWithoutNameOrUid() =
+            queryEvents("${Events.DIRTY} AND ${Events.ORIGINAL_ID} IS NULL AND " +
+                    "(${Events._SYNC_ID} IS NULL OR ${Events.UID_2445} IS NULL)", null)
+
+    override fun findByName(name: String) =
+            queryEvents("${Events._SYNC_ID}=?", arrayOf(name)).firstOrNull()
+
+
+    override fun markNotDirty(flags: Int): Int {
+        val values = ContentValues(1)
+        values.put(LocalEvent.COLUMN_FLAGS, flags)
+        return provider.update(eventsSyncURI(), values,
+                "${Events.CALENDAR_ID}=? AND NOT ${Events.DIRTY} AND ${Events.ORIGINAL_ID} IS NULL",
+                arrayOf(id.toString()))
+    }
+
+    override fun removeNotDirtyMarked(flags: Int): Int {
+        var deleted = 0
+        // list all non-dirty events with the given flags and delete every row + its exceptions
+        provider.query(eventsSyncURI(), arrayOf(Events._ID),
+                "${Events.CALENDAR_ID}=? AND NOT ${Events.DIRTY} AND ${Events.ORIGINAL_ID} IS NULL AND ${LocalEvent.COLUMN_FLAGS}=?",
+                arrayOf(id.toString(), flags.toString()), null)?.use { cursor ->
+            val batch = BatchOperation(provider)
+            while (cursor.moveToNext()) {
+                val id = cursor.getLong(0)
+                // delete event and possible exceptions (content provider doesn't delete exceptions itself)
+                batch.enqueue(BatchOperation.Operation(
+                        ContentProviderOperation.newDelete(eventsSyncURI())
+                                .withSelection("${Events._ID}=? OR ${Events.ORIGINAL_ID}=?", arrayOf(id.toString(), id.toString()))
+                ))
+            }
+            deleted = batch.commit()
+        }
+        return deleted
+    }
+
+    override fun forgetETags() {
+        val values = ContentValues(1)
+        values.putNull(LocalEvent.COLUMN_ETAG)
+        provider.update(eventsSyncURI(), values, "${Events.CALENDAR_ID}=?",
+                arrayOf(id.toString()))
+    }
+
+
+    fun processDirtyExceptions() {
+        // 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.CALENDAR_ID}=? AND ${Events.DELETED} AND ${Events.ORIGINAL_ID} IS NOT NULL",
+                arrayOf(id.toString()), null)?.use { cursor ->
+            while (cursor.moveToNext()) {
+                Logger.log.fine("Found deleted exception, removing and re-scheduling original event (if available)")
+                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 ->
+                    if (cursor2.moveToNext()) {
+                        // original event is available
+                        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)
+                        ))
+                    }
+                }
+
+                // completely remove deleted 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.CALENDAR_ID}=? AND ${Events.DIRTY} AND ${Events.ORIGINAL_ID} IS NOT NULL",
+                arrayOf(id.toString()), 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()
+            }
+        }
+    }
+
+
+    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 +1,88 @@
+/*
+ * 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.provider.CalendarContract.Events
+import at.bitfire.davdroid.model.SyncState
+
+interface LocalCollection<out T: LocalResource<*>> {
+
+    /** a tag that uniquely identifies the collection (DAVx5-wide) */
+    val tag: String
+
+    /** collection title (used for user notifications etc.) **/
+    val title: String
+
+    var lastSyncState: SyncState?
+
+    /**
+     * Finds local resources of this collection which have been marked as *deleted* by the user
+     * or an app acting on their behalf.
+     *
+     * @return list of resources marked as *deleted*
+     */
+    fun findDeleted(): List<T>
+
+    /**
+     * Finds local resources of this collection which have been marked as *dirty*, i.e. resources
+     * which have been modified by the user or an app acting on their behalf.
+     *
+     * @return list of resources marked as *dirty*
+     */
+    fun findDirty(): List<T>
+
+    /**
+     * Finds local resources of this collection which do not have a file name and/or UID, but
+     * need one for synchronization.
+     *
+     * For instance, exceptions of recurring events are local resources but do not need their
+     * own file name/UID because they're sent with the same UID as the main event.
+     *
+     * @return list of resources which need file name and UID for synchronization, but don't have both of them
+     */
+    fun findDirtyWithoutNameOrUid(): List<T>
+
+    /**
+     * Finds a local resource of this collection with a given file name. (File names are assigned
+     * by the sync adapter.)
+     *
+     * @param name file name to look for
+     * @return resource with the given name, or null if none
+     */
+    fun findByName(name: String): T?
+
+
+    /**
+     * Sets the [LocalEvent.COLUMN_FLAGS] value for entries which are not dirty ([Events.DIRTY] is 0)
+     * and have an [Events.ORIGINAL_ID] of null.
+     *
+     * @param flags    value of flags to set (for instance, [LocalResource.FLAG_REMOTELY_PRESENT]])
+     *
+     * @return         number of marked entries
+     */
+    fun markNotDirty(flags: Int): Int
+
+    /**
+     * Removes entries which are not dirty ([Events.DIRTY] is 0 and an [Events.ORIGINAL_ID] is null) with
+     * a given flag combination.
+     *
+     * @param flags    exact flags value to remove entries with (for instance, if this is [LocalResource.FLAG_REMOTELY_PRESENT]],
+     *                 all entries with exactly this flag will be removed)
+     *
+     * @return         number of removed entries
+     */
+    fun removeNotDirtyMarked(flags: Int): Int
+
+
+    /**
+     * Forgets the ETags of all members so that they will be reloaded from the server during sync.
+     */
+    fun forgetETags()
+
+}

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

@@ -1,196 +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 android.provider.ContactsContract.RawContacts.Data;
-import android.support.annotation.NonNull;
-
-import java.io.FileNotFoundException;
-import java.util.HashSet;
-import java.util.Set;
-
-import at.bitfire.davdroid.BuildConfig;
-import at.bitfire.davdroid.model.UnknownProperties;
-import at.bitfire.vcard4android.AndroidAddressBook;
-import at.bitfire.vcard4android.AndroidContact;
-import at.bitfire.vcard4android.AndroidContactFactory;
-import at.bitfire.vcard4android.BatchOperation;
-import at.bitfire.vcard4android.CachedGroupMembership;
-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 final Set<Long>
-            cachedGroupMemberships = new HashSet<>(),
-            groupMemberships = new HashSet<>();
-
-
-    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);
-        }
-    }
-
-
-    @Override
-    protected void populateData(String mimeType, ContentValues row) {
-        switch (mimeType) {
-            case CachedGroupMembership.CONTENT_ITEM_TYPE:
-                cachedGroupMemberships.add(row.getAsLong(CachedGroupMembership.GROUP_ID));
-                break;
-            case GroupMembership.CONTENT_ITEM_TYPE:
-                groupMemberships.add(row.getAsLong(GroupMembership.GROUP_ROW_ID));
-                break;
-            case UnknownProperties.CONTENT_ITEM_TYPE:
-                contact.unknownProperties = row.getAsString(UnknownProperties.UNKNOWN_PROPERTIES);
-                break;
-        }
-    }
-
-    @Override
-    protected void insertDataRows(BatchOperation batch) throws ContactsStorageException {
-        super.insertDataRows(batch);
-
-        if (contact.unknownProperties != null) {
-            ContentProviderOperation.Builder builder = ContentProviderOperation.newInsert(dataSyncURI());
-            if (id == null)
-                builder.withValueBackReference(UnknownProperties.RAW_CONTACT_ID, 0);
-            else
-                builder.withValue(UnknownProperties.RAW_CONTACT_ID, id);
-            builder .withValue(UnknownProperties.MIMETYPE, UnknownProperties.CONTENT_ITEM_TYPE)
-                    .withValue(UnknownProperties.UNKNOWN_PROPERTIES, contact.unknownProperties);
-            batch.enqueue(builder.build());
-        }
-
-    }
-
-
-    public void addToGroup(BatchOperation batch, long groupID) {
-        assertID();
-        batch.enqueue(ContentProviderOperation
-                .newInsert(dataSyncURI())
-                .withValue(GroupMembership.MIMETYPE, GroupMembership.CONTENT_ITEM_TYPE)
-                .withValue(GroupMembership.RAW_CONTACT_ID, id)
-                .withValue(GroupMembership.GROUP_ROW_ID, groupID)
-                .build()
-        );
-
-        batch.enqueue(ContentProviderOperation
-                .newInsert(dataSyncURI())
-                .withValue(CachedGroupMembership.MIMETYPE, CachedGroupMembership.CONTENT_ITEM_TYPE)
-                .withValue(CachedGroupMembership.RAW_CONTACT_ID, id)
-                .withValue(CachedGroupMembership.GROUP_ID, groupID)
-                .withYieldAllowed(true)
-                .build()
-        );
-    }
-
-    public void removeGroupMemberships(BatchOperation batch) {
-        assertID();
-        batch.enqueue(ContentProviderOperation
-                .newDelete(dataSyncURI())
-                .withSelection(
-                        Data.RAW_CONTACT_ID + "=? AND " + Data.MIMETYPE + " IN (?,?)",
-                        new String[] { String.valueOf(id), GroupMembership.CONTENT_ITEM_TYPE, CachedGroupMembership.CONTENT_ITEM_TYPE }
-                )
-                .withYieldAllowed(true)
-                .build()
-        );
-    }
-
-    /**
-     * 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
-     */
-    @NonNull
-    public Set<Long> getCachedGroupMemberships() throws ContactsStorageException, FileNotFoundException {
-        getContact();
-        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
-     */
-    @NonNull
-    public Set<Long> getGroupMemberships() throws ContactsStorageException, FileNotFoundException {
-        getContact();
-        return groupMemberships;
-    }
-
-
-    // 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);
-        }
-
-        @Override
-        public LocalContact[] newArray(int size) {
-            return new LocalContact[size];
-        }
-
-    }
-
-}

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

@@ -0,0 +1,253 @@
+/*
+ * 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, LocalAddress {
+
+    companion object {
+        init {
+            Contact.productID = "+//IDN bitfire.at//${BuildConfig.userAgent}/${BuildConfig.VERSION_NAME} ez-vcard/" + Ezvcard.VERSION
+        }
+
+        const val COLUMN_FLAGS = ContactsContract.RawContacts.SYNC4
+        const val COLUMN_HASHCODE = ContactsContract.RawContacts.SYNC3
+    }
+
+    private val cachedGroupMemberships = HashSet<Long>()
+    private val groupMemberships = HashSet<Long>()
+
+    override var flags: Int = 0
+
+    constructor(addressBook: AndroidAddressBook<LocalContact,*>, values: ContentValues)
+            : super(addressBook, values) {
+        flags = values.getAsInteger(COLUMN_FLAGS) ?: 0
+    }
+
+    constructor(addressBook: AndroidAddressBook<LocalContact,*>, contact: Contact, fileName: String?, eTag: String?, flags: Int)
+            : super(addressBook, contact, fileName, eTag) {
+        this.flags = flags
+    }
+
+
+    override fun assignNameAndUID() {
+        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
+    }
+
+    override fun clearDirty(eTag: String?) {
+        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
+    }
+
+    override fun resetDeleted() {
+        val values = ContentValues(1)
+        values.put(ContactsContract.Groups.DELETED, 0)
+        addressBook.provider!!.update(rawContactSyncURI(), values, null, null)
+    }
+
+    fun resetDirty() {
+        val values = ContentValues(1)
+        values.put(ContactsContract.RawContacts.DIRTY, 0)
+        addressBook.provider!!.update(rawContactSyncURI(), values, null, null)
+    }
+
+    override fun updateFlags(flags: Int) {
+        val values = ContentValues(1)
+        values.put(COLUMN_FLAGS, flags)
+        addressBook.provider!!.update(rawContactSyncURI(), values, null, null)
+
+        this.flags = flags
+    }
+
+
+    override fun populateData(mimeType: String, row: ContentValues) {
+        when (mimeType) {
+            CachedGroupMembership.CONTENT_ITEM_TYPE ->
+                cachedGroupMemberships += row.getAsLong(CachedGroupMembership.GROUP_ID)
+            GroupMembership.CONTENT_ITEM_TYPE ->
+                groupMemberships += row.getAsLong(GroupMembership.GROUP_ROW_ID)
+            UnknownProperties.CONTENT_ITEM_TYPE ->
+                contact!!.unknownProperties = row.getAsString(UnknownProperties.UNKNOWN_PROPERTIES)
+        }
+    }
+
+    override fun insertDataRows(batch: BatchOperation) {
+        super.insertDataRows(batch)
+
+        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)
+        }
+    }
+
+
+    /**
+     * 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)
+     */
+    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
+    }
+
+    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)
+        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))
+        }
+    }
+
+    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")
+
+        addressBook.provider!!.query(rawContactSyncURI(), arrayOf(COLUMN_HASHCODE), null, null, null)?.use { c ->
+            if (c.moveToNext() && !c.isNull(0))
+                return c.getInt(0)
+        }
+        return 0
+    }
+
+
+    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 += 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 += 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 DAVx5 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 FileNotFoundException if the current contact can't be found
+     * @throws RemoteException on contacts provider errors
+     */
+    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 FileNotFoundException if the current contact can't be found
+     * @throws RemoteException on contacts provider errors
+     */
+    fun getGroupMemberships(): Set<Long> {
+        contact
+        return groupMemberships
+    }
+
+
+    // data rows
+    override fun buildContact(builder: ContentProviderOperation.Builder, update: Boolean) {
+        builder.withValue(COLUMN_FLAGS, flags)
+        super.buildContact(builder, update)
+    }
+
+    // factory
+
+    object Factory: AndroidContactFactory<LocalContact> {
+        override fun fromProvider(addressBook: AndroidAddressBook<LocalContact, *>, values: ContentValues) =
+                LocalContact(addressBook, values)
+    }
+
+}

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 +1,130 @@
+/*
+ * 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.davdroid.BuildConfig
+import at.bitfire.ical4android.*
+import net.fortuna.ical4j.model.property.ProdId
+import java.util.*
+
+class LocalEvent: AndroidEvent, LocalResource<Event> {
+
+    companion object {
+        init {
+            ICalendar.prodId = ProdId("+//IDN bitfire.at//${BuildConfig.userAgent}/${BuildConfig.VERSION_NAME} ical4j/" + Constants.ical4jVersion)
+        }
+
+        const val COLUMN_ETAG = Events.SYNC_DATA1
+        const val COLUMN_FLAGS = Events.SYNC_DATA2
+        const val COLUMN_SEQUENCE = Events.SYNC_DATA3
+    }
+
+    override var fileName: String? = null
+        private set
+
+    override var eTag: String? = null
+
+    override var flags: Int = 0
+        private set
+
+    var weAreOrganizer = true
+
+
+    constructor(calendar: AndroidCalendar<*>, event: Event, fileName: String?, eTag: String?, flags: Int): super(calendar, event) {
+        this.fileName = fileName
+        this.eTag = eTag
+        this.flags = flags
+    }
+
+    private constructor(calendar: AndroidCalendar<*>, values: ContentValues): super(calendar, values) {
+        fileName = values.getAsString(Events._SYNC_ID)
+        eTag = values.getAsString(COLUMN_ETAG)
+        flags = values.getAsInteger(COLUMN_FLAGS) ?: 0
+    }
+
+    override fun populateEvent(row: ContentValues) {
+        super.populateEvent(row)
+        val event = requireNotNull(event)
+
+        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
+    }
+
+    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(Events.DIRTY, 0)
+                .withValue(Events.DELETED, 0)
+                .withValue(COLUMN_FLAGS, flags)
+
+        if (buildException)
+            builder .withValue(Events.ORIGINAL_SYNC_ID, fileName)
+        else
+            builder .withValue(Events._SYNC_ID, fileName)
+                    .withValue(COLUMN_ETAG, eTag)
+    }
+
+
+    override fun assignNameAndUID() {
+        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
+    }
+
+    override fun clearDirty(eTag: String?) {
+        val values = ContentValues(2)
+        values.put(Events.DIRTY, 0)
+        values.put(COLUMN_ETAG, eTag)
+        values.put(COLUMN_SEQUENCE, event!!.sequence)
+        calendar.provider.update(eventSyncURI(), values, null, null)
+
+        this.eTag = eTag
+    }
+
+    override fun updateFlags(flags: Int) {
+        val values = ContentValues(1)
+        values.put(COLUMN_FLAGS, flags)
+        calendar.provider.update(eventSyncURI(), values, null, null)
+
+        this.flags = flags
+    }
+
+
+    object Factory: AndroidEventFactory<LocalEvent> {
+        override fun fromProvider(calendar: AndroidCalendar<*>, values: ContentValues) =
+                LocalEvent(calendar, values)
+    }
+
+}

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

@@ -1,253 +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.ContentUris;
-import android.content.ContentValues;
-import android.database.Cursor;
-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 android.provider.ContactsContract.RawContactsEntity;
-
-import org.apache.commons.lang3.ArrayUtils;
-
-import java.io.FileNotFoundException;
-import java.util.LinkedList;
-import java.util.List;
-import java.util.logging.Level;
-
-import at.bitfire.dav4android.Constants;
-import at.bitfire.vcard4android.AndroidAddressBook;
-import at.bitfire.vcard4android.AndroidGroup;
-import at.bitfire.vcard4android.AndroidGroupFactory;
-import at.bitfire.vcard4android.BatchOperation;
-import at.bitfire.vcard4android.CachedGroupMembership;
-import at.bitfire.vcard4android.Contact;
-import at.bitfire.vcard4android.ContactsStorageException;
-import lombok.Cleanup;
-import lombok.ToString;
-
-@ToString(callSuper=true)
-public class LocalGroup extends AndroidGroup implements LocalResource {
-    /** marshalled list of member UIDs, as sent by server */
-    public static final String COLUMN_PENDING_MEMBERS = Groups.SYNC3;
-
-    public LocalGroup(AndroidAddressBook addressBook, long id, String fileName, String eTag) {
-        super(addressBook, id, fileName, eTag);
-    }
-
-    public LocalGroup(AndroidAddressBook addressBook, Contact contact, String fileName, String eTag) {
-        super(addressBook, contact, fileName, eTag);
-    }
-
-
-    @Override
-    public void clearDirty(String eTag) throws ContactsStorageException {
-        assertID();
-
-        ContentValues values = new ContentValues(2);
-        values.put(Groups.DIRTY, 0);
-        values.put(COLUMN_ETAG, this.eTag = eTag);
-        update(values);
-
-        // update cached group memberships
-        BatchOperation batch = new BatchOperation(addressBook.provider);
-
-        // delete cached group memberships
-        batch.enqueue(ContentProviderOperation
-                .newDelete(addressBook.syncAdapterURI(ContactsContract.Data.CONTENT_URI))
-                .withSelection(
-                        CachedGroupMembership.MIMETYPE + "=? AND " + CachedGroupMembership.GROUP_ID + "=?",
-                        new String[] { CachedGroupMembership.CONTENT_ITEM_TYPE, String.valueOf(id) }
-                ).build()
-        );
-
-        // insert updated cached group memberships
-        for (long member : getMembers())
-            batch.enqueue(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)
-                    .build()
-            );
-
-        batch.commit();
-    }
-
-    @Override
-    public void updateFileNameAndUID(String uid) throws ContactsStorageException {
-        String newFileName = uid + ".vcf";
-
-        ContentValues values = new ContentValues(2);
-        values.put(COLUMN_FILENAME, newFileName);
-        values.put(COLUMN_UID, uid);
-        update(values);
-
-        fileName = newFileName;
-    }
-
-    @Override
-    protected ContentValues contentValues() {
-        ContentValues values = super.contentValues();
-
-        @Cleanup("recycle") Parcel members = Parcel.obtain();
-        members.writeStringList(contact.members);
-        values.put(COLUMN_PENDING_MEMBERS, members.marshall());
-
-        return values;
-    }
-
-
-    /**
-     * Marks all members of the current group as dirty.
-     */
-    public void markMembersDirty() throws ContactsStorageException {
-        assertID();
-        BatchOperation batch = new BatchOperation(addressBook.provider);
-
-        for (long member : getMembers())
-            batch.enqueue(ContentProviderOperation
-                    .newUpdate(addressBook.syncAdapterURI(ContentUris.withAppendedId(RawContacts.CONTENT_URI, member)))
-                    .withValue(RawContacts.DIRTY, 1)
-                    .withYieldAllowed(true)
-                    .build()
-            );
-
-        batch.commit();
-    }
-
-    /**
-     * 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
-     */
-    public static void applyPendingMemberships(LocalAddressBook addressBook) throws ContactsStorageException {
-        try {
-            @Cleanup Cursor cursor = addressBook.provider.query(
-                    addressBook.syncAdapterURI(Groups.CONTENT_URI),
-                    new String[] { Groups._ID, COLUMN_PENDING_MEMBERS },
-                    COLUMN_PENDING_MEMBERS + " IS NOT NULL", new String[] {},
-                    null
-            );
-
-            BatchOperation batch = new BatchOperation(addressBook.provider);
-            while (cursor != null && cursor.moveToNext()) {
-                long id = cursor.getLong(0);
-                Constants.log.fine("Assigning members to group " + id);
-
-                // delete all memberships and cached memberships for this group
-                batch.enqueue(ContentProviderOperation
-                        .newDelete(addressBook.syncAdapterURI(ContactsContract.Data.CONTENT_URI))
-                        .withSelection(
-                                "(" + GroupMembership.MIMETYPE + "=? AND " + GroupMembership.GROUP_ROW_ID + "=?) OR (" +
-                                      CachedGroupMembership.MIMETYPE + "=? AND " + CachedGroupMembership.GROUP_ID + "=?)",
-                                new String[] { GroupMembership.CONTENT_ITEM_TYPE, String.valueOf(id), CachedGroupMembership.CONTENT_ITEM_TYPE, String.valueOf(id) })
-                        .withYieldAllowed(true)
-                        .build()
-                );
-
-                // extract list of member UIDs
-                List<String> members = new LinkedList<>();
-                byte[] raw = cursor.getBlob(1);
-                @Cleanup("recycle") Parcel parcel = Parcel.obtain();
-                parcel.unmarshall(raw, 0, raw.length);
-                parcel.setDataPosition(0);
-                parcel.readStringList(members);
-
-                // insert memberships
-                for (String uid : members) {
-                    Constants.log.fine("Assigning member: " + uid);
-                    try {
-                        LocalContact member = addressBook.findContactByUID(uid);
-                        member.addToGroup(batch, id);
-                    } catch(FileNotFoundException e) {
-                        Constants.log.log(Level.WARNING, "Group member not found: " + uid, e);
-                    }
-                }
-
-                // remove pending memberships
-                batch.enqueue(ContentProviderOperation
-                        .newUpdate(addressBook.syncAdapterURI(ContentUris.withAppendedId(Groups.CONTENT_URI, id)))
-                        .withValue(COLUMN_PENDING_MEMBERS, null)
-                        .withYieldAllowed(true)
-                        .build()
-                );
-
-                batch.commit();
-            }
-        } catch(RemoteException e) {
-            throw new ContactsStorageException("Couldn't get pending memberships", e);
-        }
-    }
-
-
-    // helpers
-
-    private void assertID() {
-        if (id == null)
-            throw new IllegalStateException("Group has not been saved yet");
-    }
-
-    /**
-     * Lists all members of this group.
-     * @return list of all members' raw contact IDs
-     * @throws ContactsStorageException on contact provider errors
-     */
-    protected long[] getMembers() throws ContactsStorageException {
-        assertID();
-        List<Long> members = new LinkedList<>();
-        try {
-            @Cleanup Cursor cursor = addressBook.provider.query(
-                    addressBook.syncAdapterURI(ContactsContract.Data.CONTENT_URI),
-                    new String[] { Data.RAW_CONTACT_ID },
-                    GroupMembership.MIMETYPE + "=? AND " + GroupMembership.GROUP_ROW_ID + "=?",
-                    new String[] { GroupMembership.CONTENT_ITEM_TYPE, String.valueOf(id) },
-                    null
-            );
-            while (cursor != null && cursor.moveToNext())
-                members.add(cursor.getLong(0));
-        } catch(RemoteException e) {
-            throw new ContactsStorageException("Couldn't list group members", e);
-        }
-        return ArrayUtils.toPrimitive(members.toArray(new Long[members.size()]));
-    }
-
-
-    // factory
-
-    static class Factory extends AndroidGroupFactory {
-        static final Factory INSTANCE = new Factory();
-
-        @Override
-        public LocalGroup newInstance(AndroidAddressBook addressBook, long id, String fileName, String eTag) {
-            return new LocalGroup(addressBook, id, fileName, eTag);
-        }
-
-        @Override
-        public LocalGroup newInstance(AndroidAddressBook addressBook, Contact contact, String fileName, String eTag) {
-            return new LocalGroup(addressBook, contact, fileName, eTag);
-        }
-
-        @Override
-        public LocalGroup[] newArray(int size) {
-            return new LocalGroup[size];
-        }
-
-    }
-
-}

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

@@ -0,0 +1,246 @@
+/*
+ * 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.net.Uri
+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.dav4jvm.Constants
+import at.bitfire.vcard4android.*
+import java.util.*
+
+class LocalGroup: AndroidGroup, LocalAddress {
+
+    companion object {
+
+        const val COLUMN_FLAGS = Groups.SYNC4
+
+        /** marshaled list of member UIDs, as sent by server */
+        const 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
+         */
+        fun applyPendingMemberships(addressBook: LocalAddressBook) {
+            addressBook.provider!!.query(
+                    addressBook.groupsSyncUri(),
+                    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 += 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")
+                        addressBook.findContactByUID(uid)?.let { member ->
+                            member.addToGroup(batch, id)
+                            changeContactIDs += member.id!!
+                        } ?: Constants.log.warning("Group member not found: $uid")
+                    }
+
+                    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.N && Build.VERSION.SDK_INT < Build.VERSION_CODES.O)
+                        // workaround for Android 7 which sets DIRTY flag when only meta-data is changed
+                        changeContactIDs
+                                .map { addressBook.findContactByID(it) }
+                                .forEach { it.updateHashCode(batch) }
+
+                    // remove pending memberships
+                    batch.enqueue(BatchOperation.Operation(
+                            ContentProviderOperation.newUpdate(addressBook.syncAdapterURI(ContentUris.withAppendedId(Groups.CONTENT_URI, id)))
+                                    .withValue(COLUMN_PENDING_MEMBERS, null)
+                                    .withYieldAllowed(true)
+                            ))
+
+                    batch.commit()
+                }
+            }
+        }
+
+    }
+
+
+    override var flags: Int = 0
+
+
+    constructor(addressBook: AndroidAddressBook<out AndroidContact, LocalGroup>, values: ContentValues)
+        : super(addressBook, values) {
+        flags = values.getAsInteger(COLUMN_FLAGS) ?: 0
+    }
+
+    constructor(addressBook: AndroidAddressBook<out AndroidContact, LocalGroup>, contact: Contact, fileName: String?, eTag: String?, flags: Int)
+        : super(addressBook, contact, fileName, eTag) {
+        this.flags = flags
+    }
+
+
+    override fun contentValues(): ContentValues  {
+        val values = super.contentValues()
+        values.put(COLUMN_FLAGS, flags)
+
+        val members = Parcel.obtain()
+        try {
+            members.writeStringList(contact!!.members)
+            values.put(COLUMN_PENDING_MEMBERS, members.marshall())
+        } finally {
+            members.recycle()
+        }
+        return values
+    }
+
+
+    override fun assignNameAndUID() {
+        val uid = UUID.randomUUID().toString()
+        val newFileName = "$uid.vcf"
+
+        val values = ContentValues(2)
+        values.put(COLUMN_FILENAME, newFileName)
+        values.put(COLUMN_UID, uid)
+        update(values)
+
+        fileName = newFileName
+    }
+
+    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()
+    }
+
+    /**
+     * Marks all members of the current group as dirty.
+     */
+    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()
+    }
+
+    override fun resetDeleted() {
+        val values = ContentValues(1)
+        values.put(Groups.DELETED, 0)
+        addressBook.provider!!.update(groupSyncUri(), values, null, null)
+    }
+
+    override fun updateFlags(flags: Int) {
+        val values = ContentValues(1)
+        values.put(COLUMN_FLAGS, flags)
+        addressBook.provider!!.update(groupSyncUri(), values, null, null)
+
+        this.flags = flags
+    }
+
+
+    // helpers
+
+    private fun groupSyncUri(): Uri {
+        val id = requireNotNull(id)
+        return ContentUris.withAppendedId(addressBook.groupsSyncUri(), id)
+    }
+
+    /**
+     * Lists all members of this group.
+     * @return list of all members' raw contact IDs
+     * @throws RemoteException on contact provider errors
+     */
+    internal fun getMembers(): List<Long> {
+        val id = requireNotNull(id)
+        val members = LinkedList<Long>()
+        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 += cursor.getLong(0)
+        }
+        return members
+    }
+
+
+    // factory
+
+    object Factory: AndroidGroupFactory<LocalGroup> {
+        override fun fromProvider(addressBook: AndroidAddressBook<out AndroidContact, LocalGroup>, values: ContentValues) =
+                LocalGroup(addressBook, values)
+    }
+
+}

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 +1,77 @@
+/*
+ * 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.net.Uri
+
+interface LocalResource<in TData: Any> {
+
+    companion object {
+        /**
+         * Resource is present on remote server. This flag is used to identify resources
+         * which are not present on the remote server anymore and can be deleted at the end
+         * of the synchronization.
+         */
+        const val FLAG_REMOTELY_PRESENT = 1
+    }
+
+
+    /**
+     * Unique ID which identifies the resource in the local storage. May be null if the
+     * resource has not been saved yet.
+     */
+    val id: Long?
+
+    /**
+     * Remote file name for the resource, for instance `mycontact.vcf`.
+     */
+    val fileName: String?
+    var eTag: String?
+    val flags: Int
+
+    /**
+     * Generates a new UID and file name and assigns them to this resource. Typically used
+     * before uploading a resource which has just been created locally.
+     */
+    fun assignNameAndUID()
+
+    /**
+     * Unsets the /dirty/ field of the resource. Typically used after successfully uploading a
+     * locally modified resource.
+     *
+     * @param eTag ETag of the uploaded resource as returned by the server (null if the server didn't return one)
+     */
+    fun clearDirty(eTag: String?)
+
+    /**
+     * Sets (local) flags of the resource. At the moment, the only allowed values are
+     * 0 and [FLAG_REMOTELY_PRESENT].
+     */
+    fun updateFlags(flags: Int)
+
+
+    /**
+     * Adds the data object to the content provider and ensures that the dirty flag is clear.
+     * @return content URI of the created row (e.g. event URI)
+     */
+    fun add(): Uri
+
+    /**
+     * Updates the data object in the content provider and ensures that the dirty flag is clear.
+     * @return content URI of the updated row (e.g. event URI)
+     */
+    fun update(data: TData): Uri
+
+    /**
+     * Deletes the data object from the content provider.
+     * @return number of affected rows
+     */
+    fun delete(): Int
+
+}

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 +1,101 @@
+/*
+ * 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 at.bitfire.ical4android.AndroidTask
+import at.bitfire.ical4android.AndroidTaskFactory
+import at.bitfire.ical4android.AndroidTaskList
+import at.bitfire.ical4android.Task
+import org.dmfs.tasks.contract.TaskContract.Tasks
+import java.util.*
+
+class LocalTask: AndroidTask, LocalResource<Task> {
+
+    companion object {
+        const val COLUMN_ETAG = Tasks.SYNC1
+        const val COLUMN_FLAGS = Tasks.SYNC2
+    }
+
+    override var fileName: String? = null
+    override var eTag: String? = null
+
+    override var flags = 0
+        private set
+
+
+    constructor(taskList: AndroidTaskList<*>, task: Task, fileName: String?, eTag: String?, flags: Int)
+            : super(taskList, task) {
+        this.fileName = fileName
+        this.eTag = eTag
+        this.flags = flags
+    }
+
+    private constructor(taskList: AndroidTaskList<*>, values: ContentValues): super(taskList) {
+        id = values.getAsLong(Tasks._ID)
+        fileName = values.getAsString(Tasks._SYNC_ID)
+        eTag = values.getAsString(COLUMN_ETAG)
+        flags = values.getAsInteger(COLUMN_FLAGS) ?: 0
+    }
+
+
+    /* process LocalTask-specific fields */
+
+    override fun buildTask(builder: ContentProviderOperation.Builder, update: Boolean) {
+        super.buildTask(builder, update)
+
+        builder .withValue(Tasks._SYNC_ID, fileName)
+                .withValue(COLUMN_ETAG, eTag)
+                .withValue(COLUMN_FLAGS, flags)
+    }
+
+
+    /* custom queries */
+
+    override fun assignNameAndUID() {
+        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
+    }
+
+    override fun clearDirty(eTag: String?) {
+        val values = ContentValues(3)
+        values.put(Tasks._DIRTY, 0)
+        values.put(COLUMN_ETAG, eTag)
+        values.put(Tasks.SYNC_VERSION, task!!.sequence)
+        taskList.provider.client.update(taskSyncURI(), values, null, null)
+
+        this.eTag = eTag
+    }
+
+    override fun updateFlags(flags: Int) {
+        if (id != null) {
+            val values = ContentValues(1)
+            values.put(COLUMN_FLAGS, flags)
+            taskList.provider.client.update(taskSyncURI(), values, null, null)
+        }
+
+        this.flags = flags
+    }
+
+
+    object Factory: AndroidTaskFactory<LocalTask> {
+        override fun fromProvider(taskList: AndroidTaskList<*>, values: ContentValues) =
+                LocalTask(taskList, values)
+    }
+}

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

@@ -1,167 +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.ContentValues;
-import android.content.Context;
-import android.database.Cursor;
-import android.net.Uri;
-import android.os.Build;
-import android.os.RemoteException;
-import android.support.annotation.NonNull;
-import android.text.TextUtils;
-
-import org.dmfs.provider.tasks.TaskContract.TaskLists;
-import org.dmfs.provider.tasks.TaskContract.Tasks;
-
-import java.io.FileNotFoundException;
-
-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 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, true);
-        values.put(TaskLists.OWNER, account.name);
-        values.put(TaskLists.SYNC_ENABLED, 1);
-        values.put(TaskLists.VISIBLE, 1);
-        return create(account, provider, values);
-    }
-
-    public void update(CollectionInfo info, boolean updateColor) throws CalendarStorageException {
-        update(valuesFromCollectionInfo(info, updateColor));
-    }
-
-    private static ContentValues valuesFromCollectionInfo(CollectionInfo info, boolean withColor) {
-        ContentValues values = new ContentValues();
-        values.put(TaskLists._SYNC_ID, info.url);
-        values.put(TaskLists.LIST_NAME, !TextUtils.isEmpty(info.displayName) ? info.displayName : DavUtils.lastSegmentOfUrl(info.url));
-
-        if (withColor)
-            values.put(TaskLists.LIST_COLOR, info.color != null ? info.color : defaultColor);
-
-        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 Context context) {
-        if (tasksProviderAvailable != null)
-            return tasksProviderAvailable;
-        else {
-            if (Build.VERSION.SDK_INT >= 23)
-                return context.getPackageManager().resolveContentProvider(TaskProvider.ProviderName.OpenTasks.authority, 0) != null;
-            else {
-                @Cleanup TaskProvider provider = TaskProvider.acquire(context.getContentResolver(), 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 +1,173 @@
+/*
+ * 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.annotation.SuppressLint
+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.Constants
+import at.bitfire.davdroid.DavUtils
+import at.bitfire.davdroid.closeCompat
+import at.bitfire.davdroid.log.Logger
+import at.bitfire.davdroid.model.Collection
+import at.bitfire.davdroid.model.SyncState
+import at.bitfire.ical4android.AndroidTaskList
+import at.bitfire.ical4android.AndroidTaskListFactory
+import at.bitfire.ical4android.TaskProvider
+import org.dmfs.tasks.contract.TaskContract.TaskLists
+import org.dmfs.tasks.contract.TaskContract.Tasks
+import java.util.logging.Level
+
+class LocalTaskList private constructor(
+        account: Account,
+        provider: TaskProvider,
+        id: Long
+): AndroidTaskList<LocalTask>(account, provider, LocalTask.Factory, id), LocalCollection<LocalTask> {
+
+    companion object {
+
+        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
+                try {
+                    TaskProvider.acquire(context, TaskProvider.ProviderName.OpenTasks)?.use {
+                        return true
+                    }
+                } catch (e: Exception) {
+                    // couldn't acquire task provider
+                }
+                return false
+        }
+
+        fun create(account: Account, provider: TaskProvider, info: Collection): 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)
+        }
+
+        @SuppressLint("Recycle")
+        @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, "${Tasks.ACCOUNT_NAME}=?", arrayOf(oldName))
+                }
+            } finally {
+                client?.closeCompat()
+            }
+        }
+
+        private fun valuesFromCollectionInfo(info: Collection, withColor: Boolean): ContentValues {
+            val values = ContentValues(3)
+            values.put(TaskLists._SYNC_ID, info.url.toString())
+            values.put(TaskLists.LIST_NAME, if (info.displayName.isNullOrBlank()) DavUtils.lastSegmentOfUrl(info.url) else info.displayName)
+
+            if (withColor)
+                values.put(TaskLists.LIST_COLOR, info.color ?: Constants.DAVDROID_GREEN_RGBA)
+
+            return values
+        }
+
+    }
+
+    override val tag: String
+        get() = "tasks-${account.name}-$id"
+
+    override val title: String
+        get() = name ?: id.toString()
+
+    override var lastSyncState: SyncState?
+        get() {
+            try {
+                provider.client.query(taskListSyncUri(), arrayOf(TaskLists.SYNC_VERSION),
+                        null, null, null)?.use { cursor ->
+                    if (cursor.moveToNext())
+                        cursor.getString(0)?.let {
+                            return SyncState.fromString(it)
+                        }
+                }
+            } catch (e: Exception) {
+                Logger.log.log(Level.WARNING, "Couldn't read sync state", e)
+            }
+            return null
+        }
+        set(state) {
+            val values = ContentValues(1)
+            values.put(TaskLists.SYNC_VERSION, state?.toString())
+            provider.client.update(taskListSyncUri(), values, null, null)
+        }
+
+
+    fun update(info: Collection, updateColor: Boolean) =
+            update(valuesFromCollectionInfo(info, updateColor))
+
+
+    override fun findDeleted() = queryTasks(Tasks._DELETED, null)
+
+    override fun findDirty(): List<LocalTask> {
+        val tasks = queryTasks(Tasks._DIRTY, null)
+        for (localTask in tasks) {
+            val task = requireNotNull(localTask.task)
+            val sequence = task.sequence
+            if (sequence == null)    // sequence has not been assigned yet (i.e. this task was just locally created)
+                task.sequence = 0
+            else
+                task.sequence = sequence + 1
+        }
+        return tasks
+    }
+
+    override fun findDirtyWithoutNameOrUid() =
+            queryTasks("${Tasks._DIRTY} AND (${Tasks._SYNC_ID} IS NULL OR ${Tasks._UID} IS NULL)", null)
+
+    override fun findByName(name: String) =
+            queryTasks("${Tasks._SYNC_ID}=?", arrayOf(name)).firstOrNull()
+
+
+    override fun markNotDirty(flags: Int): Int {
+        val values = ContentValues(1)
+        values.put(LocalTask.COLUMN_FLAGS, flags)
+        return provider.client.update(tasksSyncUri(), values,
+                "${Tasks.LIST_ID}=? AND ${Tasks._DIRTY}=0",
+                arrayOf(id.toString()))
+    }
+
+    override fun removeNotDirtyMarked(flags: Int) =
+            provider.client.delete(tasksSyncUri(),
+                    "${Tasks.LIST_ID}=? AND NOT ${Tasks._DIRTY} AND ${LocalTask.COLUMN_FLAGS}=?",
+                    arrayOf(id.toString(), flags.toString()))
+
+    override fun forgetETags() {
+        val values = ContentValues(1)
+        values.putNull(LocalEvent.COLUMN_ETAG)
+        provider.client.update(tasksSyncUri(), values, "${Tasks.LIST_ID}=?",
+                arrayOf(id.toString()))
+    }
+
+
+    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/AccountSettings.kt

@@ -0,0 +1,450 @@
+/*
+ * 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.accounts.Account
+import android.accounts.AccountManager
+import android.annotation.SuppressLint
+import android.content.ContentResolver
+import android.content.ContentUris
+import android.content.ContentValues
+import android.content.Context
+import android.content.pm.PackageManager
+import android.os.Bundle
+import android.os.Parcel
+import android.os.RemoteException
+import android.provider.CalendarContract
+import android.provider.ContactsContract
+import androidx.core.content.ContextCompat
+import at.bitfire.davdroid.*
+import at.bitfire.davdroid.log.Logger
+import at.bitfire.davdroid.model.AppDatabase
+import at.bitfire.davdroid.model.Collection
+import at.bitfire.davdroid.model.Credentials
+import at.bitfire.davdroid.model.Service
+import at.bitfire.davdroid.resource.LocalAddressBook
+import at.bitfire.davdroid.resource.LocalTask
+import at.bitfire.ical4android.AndroidCalendar
+import at.bitfire.ical4android.TaskProvider
+import at.bitfire.ical4android.TaskProvider.ProviderName.OpenTasks
+import at.bitfire.vcard4android.ContactsStorageException
+import at.bitfire.vcard4android.GroupMethod
+import okhttp3.HttpUrl
+import okhttp3.HttpUrl.Companion.toHttpUrlOrNull
+import org.apache.commons.lang3.StringUtils
+import org.dmfs.tasks.contract.TaskContract
+import java.util.logging.Level
+
+/**
+ * Manages settings of an account.
+ *
+ * @throws InvalidAccountException on construction when the account doesn't exist (anymore)
+ */
+@Suppress("FunctionName")
+class AccountSettings(
+        val context: Context,
+        val account: Account
+) {
+
+    companion object {
+
+        const val CURRENT_VERSION = 10
+        const val KEY_SETTINGS_VERSION = "version"
+
+        const val KEY_USERNAME = "user_name"
+        const val KEY_CERTIFICATE_ALIAS = "certificate_alias"
+
+        const val KEY_WIFI_ONLY = "wifi_only"               // sync on WiFi only (default: false)
+        const val WIFI_ONLY_DEFAULT = false
+        const val KEY_WIFI_ONLY_SSIDS = "wifi_only_ssids"   // restrict sync to specific WiFi SSIDs
+
+        /** Time range limitation to the past [in days]. Values:
+         *
+         * - null: default value (DEFAULT_TIME_RANGE_PAST_DAYS)
+         * - <0 (typically -1): no limit
+         * - n>0: entries more than n days in the past won't be synchronized
+         */
+        const val KEY_TIME_RANGE_PAST_DAYS = "time_range_past_days"
+        const val DEFAULT_TIME_RANGE_PAST_DAYS = 90
+
+        /**
+         * Whether a default alarm shall be assigned to received events/tasks which don't have an alarm.
+         * Value can be null (no default alarm) or an integer (default alarm shall be created this
+         * number of minutes before the event/task).
+         */
+        const val KEY_DEFAULT_ALARM = "default_alarm"
+
+        /* Whether DAVx5 sets the local calendar color to the value from service DB at every sync
+           value = null (not existing)     true (default)
+                   "0"                     false */
+        const val KEY_MANAGE_CALENDAR_COLORS = "manage_calendar_colors"
+
+        /* Whether DAVx5 populates and uses CalendarContract.Colors
+           value = null (not existing)     false (default)
+                   "1"                     true */
+        const val KEY_EVENT_COLORS = "event_colors"
+
+        /** Contact group method:
+        value = null (not existing)     groups as separate VCards (default)
+        "CATEGORIES"            groups are per-contact CATEGORIES
+         */
+        const val KEY_CONTACT_GROUP_METHOD = "contact_group_method"
+
+        const 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)
+    val settings = Settings.getInstance(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) ?: WIFI_ONLY_DEFAULT
+                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)
+            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)
+        return if (strDays != null) {
+            val days = strDays.toInt()
+            if (days < 0)
+                null
+            else
+                days
+        } else
+            DEFAULT_TIME_RANGE_PAST_DAYS
+    }
+
+    fun setTimeRangePastDays(days: Int?) =
+            accountManager.setUserData(account, KEY_TIME_RANGE_PAST_DAYS, (days ?: -1).toString())
+
+    /**
+     * Takes the default alarm setting (in this order) from
+     *
+     * 1. the local account settings
+     * 2. the settings provider (unless the value is -1 there).
+     *
+     * @return A default reminder shall be created this number of minutes before the start of every
+     * non-full-day event without reminder. *null*: No default reminders shall be created.
+     */
+    fun getDefaultAlarm() =
+            accountManager.getUserData(account, KEY_DEFAULT_ALARM)?.toInt() ?:
+            settings.getInt(KEY_DEFAULT_ALARM).takeIf { it != -1 }
+
+    /**
+     * Sets the default alarm value in the local account settings, if the new value differs
+     * from the value of the settings provider. If the new value is the same as the value of
+     * the settings provider, the local setting will be deleted, so that the settings provider
+     * value applies.
+     *
+     * @param minBefore The number of minutes a default reminder shall be created before the
+     * start of every non-full-day event without reminder. *null*: No default reminders shall be created.
+     */
+    fun setDefaultAlarm(minBefore: Int?) =
+            accountManager.setUserData(account, KEY_DEFAULT_ALARM,
+                    if (minBefore == settings.getInt(KEY_DEFAULT_ALARM).takeIf { it != -1 })
+                        null
+                    else
+                        minBefore?.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) ?:
+                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}_$toVersion")
+                updateProc.invoke(this)
+
+                Logger.log.info("Account version update successful")
+                accountManager.setUserData(account, KEY_SETTINGS_VERSION, toVersion.toString())
+            } catch (e: Exception) {
+                Logger.log.log(Level.SEVERE, "Couldn't update account settings", e)
+            }
+        }
+    }
+
+
+    @Suppress("unused","FunctionName")
+    /**
+     * Task synchronization now handles alarms, categories, relations and unknown properties.
+     * Setting task ETags to null will cause them to be downloaded (and parsed) again.
+     *
+     * Also update the allowed reminder types for calendars.
+     **/
+    private fun update_9_10() {
+        TaskProvider.acquire(context, OpenTasks)?.use { provider ->
+            val tasksUri = TaskProvider.syncAdapterUri(provider.tasksUri(), account)
+            val emptyETag = ContentValues(1)
+            emptyETag.putNull(LocalTask.COLUMN_ETAG)
+            provider.client.update(tasksUri, emptyETag, "${TaskContract.Tasks._DIRTY}=0 AND ${TaskContract.Tasks._DELETED}=0", null)
+        }
+
+        @SuppressLint("Recycle")
+        if (ContextCompat.checkSelfPermission(context, android.Manifest.permission.WRITE_CALENDAR) == PackageManager.PERMISSION_GRANTED)
+            context.contentResolver.acquireContentProviderClient(CalendarContract.AUTHORITY)?.let { provider ->
+                provider.update(AndroidCalendar.syncAdapterURI(CalendarContract.Calendars.CONTENT_URI, account),
+                        AndroidCalendar.calendarBaseValues, null, null)
+                provider.closeCompat()
+            }
+    }
+
+    @Suppress("unused","FunctionName")
+    /**
+     * It seems that somehow some non-CalDAV accounts got OpenTasks syncable, which caused battery problems.
+     * Disable it on those accounts for the future.
+     */
+    private fun update_8_9() {
+        val db = AppDatabase.getInstance(context)
+        val hasCalDAV = db.serviceDao().getByAccountAndType(account.name, Service.TYPE_CALDAV) != null
+        if (!hasCalDAV && ContentResolver.getIsSyncable(account, OpenTasks.authority) != 0) {
+            Logger.log.info("Disabling OpenTasks sync for $account")
+            ContentResolver.setIsSyncable(account, OpenTasks.authority, 0)
+        }
+    }
+
+    @Suppress("unused","FunctionName")
+    @SuppressLint("Recycle")
+    /**
+     * There is a mistake in this method. [TaskContract.Tasks.SYNC_VERSION] is used to store the
+     * SEQUENCE and should not be used for the eTag.
+     */
+    private fun update_7_8() {
+        TaskProvider.acquire(context, OpenTasks)?.use { provider ->
+            // ETag is now in sync_version instead of sync1
+            // UID  is now in _uid         instead of sync2
+            provider.client.query(TaskProvider.syncAdapterUri(provider.tasksUri(), account),
+                    arrayOf(TaskContract.Tasks._ID, TaskContract.Tasks.SYNC1, TaskContract.Tasks.SYNC2),
+                    "${TaskContract.Tasks.ACCOUNT_TYPE}=? AND ${TaskContract.Tasks.ACCOUNT_NAME}=?",
+                    arrayOf(account.type, account.name), null)!!.use { cursor ->
+                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")
+    @SuppressLint("Recycle")
+    private fun update_6_7() {
+        // add calendar colors
+        context.contentResolver.acquireContentProviderClient(CalendarContract.AUTHORITY)?.let { provider ->
+            try {
+                AndroidCalendar.insertColors(provider, account)
+            } finally {
+                provider.closeCompat()
+            }
+        }
+
+        // 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")
+    @SuppressLint("Recycle", "ParcelClassLoader")
+    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")?.toHttpUrlOrNull()
+                    if (url == null)
+                        Logger.log.info("No address book URL, ignoring account")
+                    else {
+                        // create new address book
+                        val info = Collection(url = url, type = Collection.TYPE_ADDRESSBOOK, 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.toString())))
+                            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()
+                provider.closeCompat()
+            }
+        }
+
+        // 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)
+    }
+
+    // updates from AccountSettings version 2 and below are not supported anymore
+
+}

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

@@ -0,0 +1,78 @@
+/*
+ * 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
+
+open class DefaultsProvider(
+        private val allowOverride: Boolean = true
+): SettingsProvider {
+
+    open val booleanDefaults = mapOf(
+            Pair(Settings.DISTRUST_SYSTEM_CERTIFICATES, Settings.DISTRUST_SYSTEM_CERTIFICATES_DEFAULT),
+            Pair(Settings.OVERRIDE_PROXY, Settings.OVERRIDE_PROXY_DEFAULT)
+    )
+
+    open val intDefaults = mapOf(
+            Pair(Settings.OVERRIDE_PROXY_PORT, Settings.OVERRIDE_PROXY_PORT_DEFAULT)
+    )
+
+    open val longDefaults = mapOf<String, Long>()
+
+    open val stringDefaults = mapOf(
+            Pair(Settings.OVERRIDE_PROXY_HOST, Settings.OVERRIDE_PROXY_HOST_DEFAULT)
+    )
+
+    override fun forceReload() {
+    }
+
+    override fun close() {
+    }
+
+
+    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
+
+
+    class Factory : ISettingsProviderFactory {
+        override fun getProviders(context: Context) = listOf(DefaultsProvider())
+    }
+
+}

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

@@ -0,0 +1,17 @@
+/*
+ * 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
+
+interface ISettingsProviderFactory {
+
+    fun getProviders(context: Context): List<SettingsProvider>
+
+}

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

@@ -0,0 +1,199 @@
+/*
+ * 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 androidx.annotation.WorkerThread
+import at.bitfire.davdroid.log.Logger
+import java.lang.ref.WeakReference
+import java.util.*
+import java.util.logging.Level
+
+class Settings(
+        appContext: Context
+) {
+
+    companion object {
+
+        // settings keys and default values
+        const val DISTRUST_SYSTEM_CERTIFICATES = "distrust_system_certs"
+        const val DISTRUST_SYSTEM_CERTIFICATES_DEFAULT = false
+        const val OVERRIDE_PROXY = "override_proxy"
+        const val OVERRIDE_PROXY_DEFAULT = false
+        const val OVERRIDE_PROXY_HOST = "override_proxy_host"
+        const val OVERRIDE_PROXY_PORT = "override_proxy_port"
+
+        const val OVERRIDE_PROXY_HOST_DEFAULT = "localhost"
+        const val OVERRIDE_PROXY_PORT_DEFAULT = 8118
+
+
+        private var singleton: Settings? = null
+
+        fun getInstance(context: Context): Settings {
+            singleton?.let { return it }
+
+            val newInstance = Settings(context.applicationContext)
+            singleton = newInstance
+            return newInstance
+        }
+
+    }
+
+    private val providers = LinkedList<SettingsProvider>()
+    private val observers = LinkedList<WeakReference<OnChangeListener>>()
+
+    init {
+        val factories = ServiceLoader.load(ISettingsProviderFactory::class.java)
+        Logger.log.fine("Loading settings providers from ${factories.count()} factories")
+        factories.forEach { factory ->
+            providers.addAll(factory.getProviders(appContext))
+        }
+    }
+
+    fun forceReload() {
+        providers.forEach {
+            it.forceReload()
+        }
+        onSettingsChanged()
+    }
+
+
+    /*** OBSERVERS ***/
+
+    fun addOnChangeListener(observer: OnChangeListener) {
+        synchronized(this) {
+            observers += WeakReference(observer)
+        }
+    }
+
+    fun removeOnChangeListener(observer: OnChangeListener) {
+        synchronized(this) {
+            observers.removeAll { it.get() == null || it.get() == observer }
+        }
+    }
+
+    fun onSettingsChanged() {
+        synchronized(this) {
+            observers.mapNotNull { it.get() }.forEach {
+                it.onSettingsChanged()
+            }
+        }
+    }
+
+
+    /*** SETTINGS ACCESS ***/
+
+    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: (SettingsProvider) -> 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: (SettingsProvider) -> 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
+    }
+
+
+    interface OnChangeListener {
+        /**
+         * Will be called when something has changed in a [SettingsProvider].
+         * Runs in worker thread!
+         */
+        @WorkerThread
+        fun onSettingsChanged()
+    }
+
+}

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

@@ -0,0 +1,32 @@
+/*
+ * 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
+
+interface SettingsProvider {
+
+    fun forceReload()
+    fun close()
+
+    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
+
+}

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

@@ -0,0 +1,132 @@
+/*
+ * 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.AppDatabase
+
+class SharedPreferencesProvider(
+        val context: Context
+): SettingsProvider, SharedPreferences.OnSharedPreferenceChangeListener {
+
+    companion object {
+        private const val META_VERSION = "version"
+        private const 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()
+        }
+
+        preferences.registerOnSharedPreferenceChangeListener(this)
+    }
+
+    override fun forceReload() {
+    }
+
+    override fun close() {
+        preferences.unregisterOnSharedPreferenceChangeListener(this)
+    }
+
+    override fun onSharedPreferenceChanged(sharedPreferences: SharedPreferences, key: String) {
+        Settings.getInstance(context).onSettingsChanged()
+    }
+
+
+    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(first = true, second = true)
+
+    private fun<T> putValue(key: String, value: T?, writer: (SharedPreferences.Editor, T) -> Unit): Boolean {
+        return if (value == null)
+            remove(key)
+        else {
+            Logger.log.fine("Writing setting $key = $value")
+            val edit = preferences.edit()
+            writer(edit, value)
+            edit.apply()
+            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
+        AppDatabase.getInstance(context)
+    }
+
+
+    class Factory : ISettingsProviderFactory {
+        override fun getProviders(context: Context) = listOf(SharedPreferencesProvider(context))
+    }
+
+}

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 +1,113 @@
+/*
+ * 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.os.Bundle
+import androidx.annotation.WorkerThread
+import at.bitfire.davdroid.R
+import at.bitfire.davdroid.log.Logger
+import at.bitfire.davdroid.model.AppDatabase
+import at.bitfire.davdroid.resource.LocalAddressBook
+import at.bitfire.davdroid.ui.setup.LoginActivity
+import java.util.logging.Level
+import kotlin.concurrent.thread
+
+
+/**
+ * Account authenticator for the main DAVx5 account type.
+ *
+ * Gets started when a DAVx5 account is removed, too, so it also watches for account removals
+ * and contains the corresponding cleanup code.
+ */
+class AccountAuthenticatorService: Service(), OnAccountsUpdateListener {
+
+    companion object {
+
+        @WorkerThread
+        fun cleanupAccounts(context: Context) {
+            Logger.log.info("Cleaning up orphaned accounts")
+
+            val accountManager = AccountManager.get(context)
+            val accountNames = accountManager.getAccountsByType(context.getString(R.string.account_type))
+                    .map { it.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.mainAccount.name))
+                                it.delete()
+                        } catch(e: Exception) {
+                            Logger.log.log(Level.SEVERE, "Couldn't delete address book account", e)
+                        }
+                    }
+
+            // delete orphaned services in DB
+            val db = AppDatabase.getInstance(context)
+            val serviceDao = db.serviceDao()
+            if (accountNames.isEmpty())
+                serviceDao.deleteAll()
+            else
+                serviceDao.deleteExceptAccounts(accountNames.toTypedArray())
+        }
+
+    }
+
+
+    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 == AccountManager.ACTION_AUTHENTICATOR_INTENT }
+
+
+    override fun onAccountsUpdated(accounts: Array<out Account>?) {
+        thread {
+            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 +1,25 @@
+/*
+ * 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
+
+@Suppress("ImplicitNullableNothingType")
+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
+
+}