implement AvailabilityDetector using chargecloud API (#1)

app/src/main/java/com/johan/evmap/api/AvailabilityDetector.kt

@@ -0,0 +1,86 @@
+package com.johan.evmap.api
+
+import kotlinx.coroutines.ExperimentalCoroutinesApi
+import okhttp3.*
+import org.json.JSONObject
+import java.io.IOException
+import java.util.concurrent.TimeUnit
+
+private const val radius = 100  // max radius in meters
+
+interface AvailabilityDetector {
+    suspend fun getAvailability(location: ChargeLocation): Map<Chargepoint, List<ChargepointStatus>>
+}
+
+enum class ChargepointStatus {
+    AVAILABLE, UNKNOWN, CHARGING
+}
+
+class ChargecloudAvailabilityDetector(private val client: OkHttpClient,
+                                      private val operatorId: String): AvailabilityDetector {
+    @ExperimentalCoroutinesApi
+    override suspend fun getAvailability(location: ChargeLocation): Map<Chargepoint, List<ChargepointStatus>> {
+        val url = "https://app.chargecloud.de/emobility:ocpi/$operatorId/app/2.0/locations?latitude=${location.coordinates.lat}&longitude=${location.coordinates.lng}&radius=$radius&offset=0&limit=10"
+        val request = Request.Builder().url(url).build()
+        val response = client.newCall(request).await()
+
+        if (!response.isSuccessful) throw IOException(response.message())
+
+        val json = JSONObject(response.body()!!.string())
+
+        val statusMessage = json.getString("status_message")
+        if (statusMessage != "Success") throw IOException(statusMessage)
+
+        val data = json.getJSONArray("data")
+        if (data.length() > 1) throw IOException("found multiple candidates.")
+        if (data.length() == 0) throw IOException("no candidates found.")
+
+        val evses = data.getJSONObject(0).getJSONArray("evses")
+        val chargepointStatus = mutableMapOf<Chargepoint, List<ChargepointStatus>>()
+        evses.iterator<JSONObject>().forEach { evse ->
+            evse.getJSONArray("connectors").iterator<JSONObject>().forEach connector@{ connector ->
+                val type = getType(connector.getString("standard"))
+                val power = connector.getDouble("max_power")
+                val status = ChargepointStatus.valueOf(connector.getString("status"))
+                if (type == null) return@connector
+
+                var chargepoint = chargepointStatus.keys.filter {
+                    it.type == type
+                    it.power == power
+                }.getOrNull(0)
+                val statusList: List<ChargepointStatus>
+                if (chargepoint == null) {
+                    chargepoint = Chargepoint(type, power, 1)
+                    statusList = listOf(status)
+                } else {
+                    val previousStatus = chargepointStatus[chargepoint]!!
+                    statusList = previousStatus + listOf(status)
+                    chargepointStatus.remove(chargepoint)
+                    chargepoint =
+                        Chargepoint(chargepoint.type, chargepoint.power, chargepoint.count + 1)
+                }
+
+                chargepointStatus[chargepoint] = statusList
+            }
+        }
+        return chargepointStatus
+    }
+
+    private fun getType(string: String): String? {
+        return when (string) {
+            "IEC_62196_T2" -> Chargepoint.TYPE_2
+            "DOMESTIC_F" -> Chargepoint.SCHUKO
+            "IEC_62196_T2_COMBO" -> Chargepoint.CCS
+            "CHADEMO" -> Chargepoint.CHADEMO
+            else -> null
+        }
+    }
+}
+
+private val okhttp = OkHttpClient.Builder()
+    .readTimeout(10, TimeUnit.SECONDS)
+    .connectTimeout(10, TimeUnit.SECONDS)
+    .build()
+val availabilityDetectors = listOf(
+    ChargecloudAvailabilityDetector(okhttp, "6336fe713f2eb7fa04b97ff6651b76f8")
+)

app/src/main/java/com/johan/evmap/api/GoingElectricModel.kt

@@ -179,4 +179,12 @@ data class Chargepoint(val type: String, val power: Double, val count: Int) : Eq
         }
         return "$powerFmt kW"
     }
+
+    companion object {
+        const val TYPE_2 = "Type2"
+        const val CCS = "CCS"
+        const val SCHUKO = "Schuko"
+        const val CHADEMO = "CHAdeMO"
+        const val SUPERCHARGER = "Tesla Supercharger"
+    }
 }

app/src/main/java/com/johan/evmap/api/Utils.kt

@@ -0,0 +1,38 @@
+package com.johan.evmap.api
+
+import kotlinx.coroutines.ExperimentalCoroutinesApi
+import kotlinx.coroutines.suspendCancellableCoroutine
+import okhttp3.Call
+import okhttp3.Callback
+import okhttp3.Response
+import org.json.JSONArray
+import org.json.JSONObject
+import java.io.IOException
+import kotlin.coroutines.resumeWithException
+
+operator fun<T> JSONArray.iterator(): Iterator<T>
+        = (0 until length()).asSequence().map { get(it) as T }.iterator()
+
+@ExperimentalCoroutinesApi
+suspend fun Call.await(): Response {
+    return suspendCancellableCoroutine { continuation ->
+        enqueue(object : Callback {
+            override fun onResponse(call: Call, response: Response) {
+                continuation.resume(response) {}
+            }
+
+            override fun onFailure(call: Call, e: IOException) {
+                if (continuation.isCancelled) return
+                continuation.resumeWithException(e)
+            }
+        })
+
+        continuation.invokeOnCancellation {
+            try {
+                cancel()
+            } catch (ex: Throwable) {
+                //Ignore cancel exception
+            }
+        }
+    }
+}

app/src/main/java/com/johan/evmap/ui/BindingAdapters.kt

@@ -10,6 +10,7 @@ import androidx.recyclerview.widget.RecyclerView
 import androidx.viewpager2.widget.ViewPager2
 import com.google.android.material.floatingactionbutton.FloatingActionButton
 import com.johan.evmap.R
+import com.johan.evmap.api.Chargepoint
 
 
 @BindingAdapter("goneUnless")
@@ -51,11 +52,11 @@ fun <T> setRecyclerViewData(recyclerView: ViewPager2, items: List<T>?) {
 fun getConnectorItem(view: ImageView, type: String) {
     view.setImageResource(
         when (type) {
-            "CCS" -> R.drawable.ic_connector_ccs
-            "CHAdeMO" -> R.drawable.ic_connector_chademo
-            "Schuko" -> R.drawable.ic_connector_schuko
-            "Tesla Supercharger" -> R.drawable.ic_connector_supercharger
-            "Typ2" -> R.drawable.ic_connector_typ2
+            Chargepoint.CCS -> R.drawable.ic_connector_ccs
+            Chargepoint.CHADEMO -> R.drawable.ic_connector_chademo
+            Chargepoint.SCHUKO -> R.drawable.ic_connector_schuko
+            Chargepoint.SUPERCHARGER -> R.drawable.ic_connector_supercharger
+            Chargepoint.TYPE_2 -> R.drawable.ic_connector_typ2
             // TODO: add other connectors
             else -> 0
         }