Changed track metadata reporting method so it could work similarly across devices (notification, ambient display, lockscreen, watches, ...) (#55).

app/src/main/java/com/github/apognu/otter/playback/MediaControlsManager.kt

@@ -18,7 +18,9 @@ import com.github.apognu.otter.utils.*
 import com.squareup.picasso.Picasso
 import kotlinx.coroutines.CoroutineScope
 import kotlinx.coroutines.Dispatchers.Default
+import kotlinx.coroutines.Dispatchers.IO
 import kotlinx.coroutines.launch
+import kotlinx.coroutines.runBlocking
 
 class MediaControlsManager(val context: Service, private val scope: CoroutineScope, private val mediaSession: MediaSessionCompat) {
   companion object {
@@ -30,6 +32,27 @@ class MediaControlsManager(val context: Service, private val scope: CoroutineSco
 
   private var notification: Notification? = null
 
+  fun buildTrackMetadata(track: Track?): MediaMetadataCompat {
+    track?.let {
+      val coverUrl = maybeNormalizeUrl(track.album.cover.original)
+
+      return MediaMetadataCompat.Builder().apply {
+        putString(MediaMetadataCompat.METADATA_KEY_TITLE, track.title)
+        putString(MediaMetadataCompat.METADATA_KEY_ARTIST, track.artist.name)
+        putLong(MediaMetadata.METADATA_KEY_DURATION, (track.bestUpload()?.duration?.toLong() ?: 0L) * 1000)
+
+        try {
+          runBlocking(IO) {
+            this@apply.putBitmap(MediaMetadataCompat.METADATA_KEY_ALBUM_ART, Picasso.get().load(coverUrl).get())
+          }
+        } catch (e: Exception) {
+        }
+      }.build()
+    }
+
+    return MediaMetadataCompat.Builder().build()
+  }
+
   fun updateNotification(track: Track?, playing: Boolean) {
     if (notification == null && !playing) return
 
@@ -44,17 +67,6 @@ class MediaControlsManager(val context: Service, private val scope: CoroutineSco
         val openPendingIntent = PendingIntent.getActivity(context, 0, openIntent, 0)
 
         val coverUrl = maybeNormalizeUrl(track.album.cover.original)
-        val cover = coverUrl?.run { Picasso.get().load(coverUrl) }
-
-        mediaSession.setMetadata(MediaMetadataCompat.Builder().apply {
-          putString(MediaMetadata.METADATA_KEY_ARTIST, track.artist.name)
-          putString(MediaMetadata.METADATA_KEY_TITLE, track.title)
-          putLong(MediaMetadata.METADATA_KEY_DURATION, (track.bestUpload()?.duration?.toLong() ?: 0L) * 1000)
-
-          cover?.let {
-            try { putBitmap(MediaMetadata.METADATA_KEY_ALBUM_ART, it.get()) } catch (_: Exception) {}
-          }
-        }.build())
 
         notification = NotificationCompat.Builder(
           context,
@@ -69,11 +81,13 @@ class MediaControlsManager(val context: Service, private val scope: CoroutineSco
           )
           .setSmallIcon(R.drawable.ottershape)
           .run {
-            if (cover != null) {
-              try { setLargeIcon(cover.get()) } catch (_: Exception) {}
+            coverUrl?.let {
+              try { setLargeIcon(Picasso.get().load(coverUrl).get()) } catch (_: Exception) {}
+
+              return@run this
+            }
 
-              this
-            } else this
+            this
           }
           .setContentTitle(track.title)
           .setContentText(track.artist.name)

app/src/main/java/com/github/apognu/otter/playback/PlayerService.kt

@@ -9,15 +9,15 @@ import android.media.AudioAttributes
 import android.media.AudioFocusRequest
 import android.media.AudioManager
 import android.os.Build
+import android.os.Bundle
 import android.os.IBinder
+import android.os.ResultReceiver
 import android.support.v4.media.session.MediaSessionCompat
+import android.support.v4.media.session.PlaybackStateCompat
 import android.view.KeyEvent
 import com.github.apognu.otter.R
 import com.github.apognu.otter.utils.*
-import com.google.android.exoplayer2.C
-import com.google.android.exoplayer2.ExoPlaybackException
-import com.google.android.exoplayer2.Player
-import com.google.android.exoplayer2.SimpleExoPlayer
+import com.google.android.exoplayer2.*
 import com.google.android.exoplayer2.ext.mediasession.MediaSessionConnector
 import com.google.android.exoplayer2.source.TrackGroupArray
 import com.google.android.exoplayer2.trackselection.TrackSelectionArray
@@ -84,6 +84,13 @@ class PlayerService : Service() {
 
     mediaSession = MediaSessionCompat(this, applicationContext.packageName).apply {
       isActive = true
+      setPlaybackState(PlaybackStateCompat.Builder()
+        .setActions(
+          PlaybackStateCompat.ACTION_PLAY_PAUSE or
+          PlaybackStateCompat.ACTION_SEEK_TO or
+          PlaybackStateCompat.ACTION_SKIP_TO_NEXT or
+          PlaybackStateCompat.ACTION_SKIP_TO_PREVIOUS
+        ).build())
     }
 
     mediaControlsManager = MediaControlsManager(this, scope, mediaSession)
@@ -97,6 +104,30 @@ class PlayerService : Service() {
 
       MediaSessionConnector(mediaSession).also {
         it.setPlayer(this)
+        it.setMediaMetadataProvider {
+          mediaControlsManager.buildTrackMetadata(queue.current())
+        }
+
+        it.setQueueNavigator(object : MediaSessionConnector.QueueNavigator {
+          override fun onSkipToQueueItem(player: Player, controlDispatcher: ControlDispatcher, id: Long) {}
+
+          override fun onCurrentWindowIndexChanged(player: Player) {}
+
+          override fun onCommand(player: Player, controlDispatcher: ControlDispatcher, command: String, extras: Bundle?, cb: ResultReceiver?) = true
+
+          override fun getSupportedQueueNavigatorActions(player: Player): Long {
+            return PlaybackStateCompat.ACTION_PLAY_PAUSE or PlaybackStateCompat.ACTION_SKIP_TO_NEXT or PlaybackStateCompat.ACTION_SKIP_TO_PREVIOUS
+          }
+
+          override fun onSkipToNext(player: Player, controlDispatcher: ControlDispatcher) {}
+
+          override fun getActiveQueueItemId(player: Player?) = 0L
+
+          override fun onSkipToPrevious(player: Player, controlDispatcher: ControlDispatcher) {}
+
+          override fun onTimelineChanged(player: Player) {}
+        })
+
         it.setMediaButtonEventHandler { player, _, mediaButtonEvent ->
           mediaButtonEvent.extras?.getParcelable<KeyEvent>(Intent.EXTRA_KEY_EVENT)?.let { key ->
             if (key.action == KeyEvent.ACTION_UP) {