Updated Events to ReactiveX

Minor fixes

ultrasonic/src/main/java/org/moire/ultrasonic/fragment/NowPlayingFragment.java

@@ -1,194 +0,0 @@
-package org.moire.ultrasonic.fragment;
-
-import android.os.Bundle;
-import android.view.LayoutInflater;
-import android.view.MotionEvent;
-import android.view.View;
-import android.view.ViewGroup;
-import android.widget.ImageView;
-import android.widget.TextView;
-
-import androidx.annotation.NonNull;
-import androidx.annotation.Nullable;
-import androidx.fragment.app.Fragment;
-import androidx.navigation.Navigation;
-
-import org.moire.ultrasonic.R;
-import org.moire.ultrasonic.domain.MusicDirectory;
-import org.moire.ultrasonic.domain.PlayerState;
-import org.moire.ultrasonic.service.DownloadFile;
-import org.moire.ultrasonic.service.MediaPlayerController;
-import org.moire.ultrasonic.service.RxBus;
-import org.moire.ultrasonic.subsonic.ImageLoaderProvider;
-import org.moire.ultrasonic.util.Constants;
-import org.moire.ultrasonic.util.NowPlayingEventDistributor;
-import org.moire.ultrasonic.util.NowPlayingEventListener;
-import org.moire.ultrasonic.util.Settings;
-import org.moire.ultrasonic.util.Util;
-
-import kotlin.Lazy;
-import kotlin.Unit;
-import timber.log.Timber;
-
-import static org.koin.java.KoinJavaComponent.inject;
-
-
-/**
- * Contains the mini-now playing information box displayed at the bottom of the screen
- */
-public class NowPlayingFragment extends Fragment {
-
-    private static final int MIN_DISTANCE = 30;
-    private float downX;
-    private float downY;
-    ImageView playButton;
-    ImageView nowPlayingAlbumArtImage;
-    TextView nowPlayingTrack;
-    TextView nowPlayingArtist;
-
-    private final Lazy<MediaPlayerController> mediaPlayerControllerLazy = inject(MediaPlayerController.class);
-    private final Lazy<ImageLoaderProvider> imageLoader = inject(ImageLoaderProvider.class);
-    private final Lazy<NowPlayingEventDistributor> nowPlayingEventDistributor = inject(NowPlayingEventDistributor.class);
-    private NowPlayingEventListener nowPlayingEventListener;
-
-    @Override
-    public void onCreate(@Nullable Bundle savedInstanceState) {
-        Util.applyTheme(this.getContext());
-        super.onCreate(savedInstanceState);
-    }
-
-    @Override
-    public View onCreateView(LayoutInflater inflater, ViewGroup container,
-                             Bundle savedInstanceState) {
-        return inflater.inflate(R.layout.now_playing, container, false);
-    }
-
-    @Override
-    public void onViewCreated(@NonNull final View view, @Nullable Bundle savedInstanceState) {
-
-        playButton = view.findViewById(R.id.now_playing_control_play);
-        nowPlayingAlbumArtImage = view.findViewById(R.id.now_playing_image);
-        nowPlayingTrack = view.findViewById(R.id.now_playing_trackname);
-        nowPlayingArtist = view.findViewById(R.id.now_playing_artist);
-
-        nowPlayingEventListener = new NowPlayingEventListener() {
-            @Override
-            public void onHideNowPlaying() { }
-            @Override
-            public void onShowNowPlaying() { update(); }
-        };
-
-        nowPlayingEventDistributor.getValue().subscribe(nowPlayingEventListener);
-    }
-
-    @Override
-    public void onResume() {
-        super.onResume();
-        update();
-    }
-
-    @Override
-    public void onDestroy() {
-        super.onDestroy();
-        nowPlayingEventDistributor.getValue().unsubscribe(nowPlayingEventListener);
-    }
-
-    private void update() {
-        try
-        {
-            PlayerState playerState = mediaPlayerControllerLazy.getValue().getPlayerState();
-            if (playerState == PlayerState.PAUSED) {
-                playButton.setImageDrawable(Util.getDrawableFromAttribute(getContext(), R.attr.media_play));
-            } else if (playerState == PlayerState.STARTED) {
-                playButton.setImageDrawable(Util.getDrawableFromAttribute(getContext(), R.attr.media_pause));
-            }
-
-            DownloadFile file = mediaPlayerControllerLazy.getValue().getCurrentPlaying();
-            if (file != null) {
-                final MusicDirectory.Entry song = file.getSong();
-                String title = song.getTitle();
-                String artist = song.getArtist();
-
-                imageLoader.getValue().getImageLoader().loadImage(nowPlayingAlbumArtImage, song, false, Util.getNotificationImageSize(getContext()));
-                nowPlayingTrack.setText(title);
-                nowPlayingArtist.setText(artist);
-
-                nowPlayingAlbumArtImage.setOnClickListener(v -> {
-                    Bundle bundle = new Bundle();
-
-                    if (Settings.getShouldUseId3Tags()) {
-                        bundle.putBoolean(Constants.INTENT_EXTRA_NAME_IS_ALBUM, true);
-                        bundle.putString(Constants.INTENT_EXTRA_NAME_ID, song.getAlbumId());
-                    } else {
-                        bundle.putBoolean(Constants.INTENT_EXTRA_NAME_IS_ALBUM, false);
-                        bundle.putString(Constants.INTENT_EXTRA_NAME_ID, song.getParent());
-                    }
-
-                    bundle.putString(Constants.INTENT_EXTRA_NAME_NAME, song.getAlbum());
-                    bundle.putString(Constants.INTENT_EXTRA_NAME_NAME, song.getAlbum());
-                    Navigation.findNavController(getActivity(), R.id.nav_host_fragment).navigate(R.id.trackCollectionFragment, bundle);
-                });
-            }
-
-            getView().setOnTouchListener((v, event) -> handleOnTouch(event));
-
-            // This empty onClickListener is necessary for the onTouchListener to work
-            getView().setOnClickListener(v -> {});
-
-            playButton.setOnClickListener(v -> mediaPlayerControllerLazy.getValue().togglePlayPause());
-        }
-        catch (Exception x) {
-            Timber.w(x, "Failed to get notification cover art");
-        }
-    }
-
-    private boolean handleOnTouch(MotionEvent event) {
-        switch (event.getAction())
-        {
-            case MotionEvent.ACTION_DOWN:
-            {
-                downX = event.getX();
-                downY = event.getY();
-                return false;
-            }
-            case MotionEvent.ACTION_UP:
-            {
-                float upX = event.getX();
-                float upY = event.getY();
-
-                float deltaX = downX - upX;
-                float deltaY = downY - upY;
-
-                if (Math.abs(deltaX) > MIN_DISTANCE)
-                {
-                    // left or right
-                    if (deltaX < 0)
-                    {
-                        mediaPlayerControllerLazy.getValue().previous();
-                        return false;
-                    }
-                    if (deltaX > 0)
-                    {
-                        mediaPlayerControllerLazy.getValue().next();
-                        return false;
-                    }
-                }
-                else if (Math.abs(deltaY) > MIN_DISTANCE)
-                {
-                    if (deltaY < 0)
-                    {
-                        RxBus.INSTANCE.getDismissNowPlayingCommandPublisher().onNext(Unit.INSTANCE);
-                        return false;
-                    }
-                    if (deltaY > 0)
-                    {
-                        return false;
-                    }
-                }
-                Navigation.findNavController(getActivity(), R.id.nav_host_fragment).navigate(R.id.playerFragment);
-                return false;
-            }
-        }
-        return false;
-    }
-}

ultrasonic/src/main/kotlin/org/moire/ultrasonic/activity/NavigationActivity.kt

@@ -48,8 +48,6 @@ import org.moire.ultrasonic.service.RxBus
 import org.moire.ultrasonic.subsonic.ImageLoaderProvider
 import org.moire.ultrasonic.util.Constants
 import org.moire.ultrasonic.util.FileUtil
-import org.moire.ultrasonic.util.NowPlayingEventDistributor
-import org.moire.ultrasonic.util.NowPlayingEventListener
 import org.moire.ultrasonic.util.PermissionUtil
 import org.moire.ultrasonic.util.ServerColor
 import org.moire.ultrasonic.util.Settings
@@ -74,14 +72,13 @@ class NavigationActivity : AppCompatActivity() {
     private var headerBackgroundImage: ImageView? = null
 
     private lateinit var appBarConfiguration: AppBarConfiguration
-    private lateinit var nowPlayingEventListener: NowPlayingEventListener
     private var themeChangedEventSubscription: Disposable? = null
+    private var playerStateSubscription: Disposable? = null
 
     private val serverSettingsModel: ServerSettingsModel by viewModel()
     private val lifecycleSupport: MediaPlayerLifecycleSupport by inject()
     private val mediaPlayerController: MediaPlayerController by inject()
     private val imageLoaderProvider: ImageLoaderProvider by inject()
-    private val nowPlayingEventDistributor: NowPlayingEventDistributor by inject()
     private val permissionUtil: PermissionUtil by inject()
     private val activeServerProvider: ActiveServerProvider by inject()
     private val serverRepository: ServerSettingDao by inject()
@@ -173,23 +170,17 @@ class NavigationActivity : AppCompatActivity() {
             hideNowPlaying()
         }
 
-        nowPlayingEventListener = object : NowPlayingEventListener {
+        playerStateSubscription = RxBus.playerStateObservable.subscribe {
-
+            if (it.state === PlayerState.STARTED || it.state === PlayerState.PAUSED)
-            override fun onHideNowPlaying() {
-                hideNowPlaying()
-            }
-
-            override fun onShowNowPlaying() {
                 showNowPlaying()
-            }
+            else
+                hideNowPlaying()
         }
 
         themeChangedEventSubscription = RxBus.themeChangedEventObservable.subscribe {
             recreate()
         }
 
-        nowPlayingEventDistributor.subscribe(nowPlayingEventListener)
-
         serverRepository.liveServerCount().observe(
             this,
             { count ->
@@ -236,8 +227,8 @@ class NavigationActivity : AppCompatActivity() {
 
     override fun onDestroy() {
         super.onDestroy()
-        nowPlayingEventDistributor.unsubscribe(nowPlayingEventListener)
         themeChangedEventSubscription?.dispose()
+        playerStateSubscription?.dispose()
         imageLoaderProvider.clearImageLoader()
         permissionUtil.onForegroundApplicationStopped()
     }

ultrasonic/src/main/kotlin/org/moire/ultrasonic/di/ApplicationModule.kt

@@ -4,9 +4,7 @@ import org.koin.android.ext.koin.androidContext
 import org.koin.dsl.module
 import org.moire.ultrasonic.data.ActiveServerProvider
 import org.moire.ultrasonic.subsonic.ImageLoaderProvider
-import org.moire.ultrasonic.util.MediaSessionEventDistributor
 import org.moire.ultrasonic.util.MediaSessionHandler
-import org.moire.ultrasonic.util.NowPlayingEventDistributor
 import org.moire.ultrasonic.util.PermissionUtil
 
 /**
@@ -16,7 +14,5 @@ val applicationModule = module {
     single { ActiveServerProvider(get()) }
     single { ImageLoaderProvider(androidContext()) }
     single { PermissionUtil(androidContext()) }
-    single { NowPlayingEventDistributor() }
-    single { MediaSessionEventDistributor() }
     single { MediaSessionHandler() }
 }

ultrasonic/src/main/kotlin/org/moire/ultrasonic/fragment/NowPlayingFragment.kt

@@ -0,0 +1,188 @@
+/*
+ * NowPlayingFragment.kt
+ * Copyright (C) 2009-2021 Ultrasonic developers
+ *
+ * Distributed under terms of the GNU GPLv3 license.
+ */
+
+package org.moire.ultrasonic.fragment
+
+import android.annotation.SuppressLint
+import android.os.Bundle
+import android.view.LayoutInflater
+import android.view.MotionEvent
+import android.view.View
+import android.view.ViewGroup
+import android.widget.ImageView
+import android.widget.TextView
+import androidx.fragment.app.Fragment
+import androidx.navigation.Navigation
+import io.reactivex.rxjava3.disposables.Disposable
+import java.lang.Exception
+import kotlin.math.abs
+import org.koin.android.ext.android.inject
+import org.moire.ultrasonic.R
+import org.moire.ultrasonic.domain.PlayerState
+import org.moire.ultrasonic.service.MediaPlayerController
+import org.moire.ultrasonic.service.RxBus
+import org.moire.ultrasonic.subsonic.ImageLoaderProvider
+import org.moire.ultrasonic.util.Constants
+import org.moire.ultrasonic.util.Settings
+import org.moire.ultrasonic.util.Util.applyTheme
+import org.moire.ultrasonic.util.Util.getDrawableFromAttribute
+import org.moire.ultrasonic.util.Util.getNotificationImageSize
+import timber.log.Timber
+
+/**
+ * Contains the mini-now playing information box displayed at the bottom of the screen
+ */
+class NowPlayingFragment : Fragment() {
+
+    private var downX = 0f
+    private var downY = 0f
+
+    private var playButton: ImageView? = null
+    private var nowPlayingAlbumArtImage: ImageView? = null
+    private var nowPlayingTrack: TextView? = null
+    private var nowPlayingArtist: TextView? = null
+
+    private var playerStateSubscription: Disposable? = null
+    private val mediaPlayerController: MediaPlayerController by inject()
+    private val imageLoader: ImageLoaderProvider by inject()
+
+    override fun onCreate(savedInstanceState: Bundle?) {
+        applyTheme(this.context)
+        super.onCreate(savedInstanceState)
+    }
+
+    override fun onCreateView(
+        inflater: LayoutInflater,
+        container: ViewGroup?,
+        savedInstanceState: Bundle?
+    ): View? {
+        return inflater.inflate(R.layout.now_playing, container, false)
+    }
+
+    override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
+        playButton = view.findViewById(R.id.now_playing_control_play)
+        nowPlayingAlbumArtImage = view.findViewById(R.id.now_playing_image)
+        nowPlayingTrack = view.findViewById(R.id.now_playing_trackname)
+        nowPlayingArtist = view.findViewById(R.id.now_playing_artist)
+        playerStateSubscription =
+            RxBus.playerStateObservable.subscribe { update() }
+    }
+
+    override fun onResume() {
+        super.onResume()
+        update()
+    }
+
+    override fun onDestroy() {
+        super.onDestroy()
+        playerStateSubscription!!.dispose()
+    }
+
+    @SuppressLint("ClickableViewAccessibility")
+    private fun update() {
+        try {
+            val playerState = mediaPlayerController.playerState
+
+            if (playerState === PlayerState.PAUSED) {
+                playButton!!.setImageDrawable(
+                    getDrawableFromAttribute(
+                        context, R.attr.media_play
+                    )
+                )
+            } else if (playerState === PlayerState.STARTED) {
+                playButton!!.setImageDrawable(
+                    getDrawableFromAttribute(
+                        context, R.attr.media_pause
+                    )
+                )
+            }
+
+            val file = mediaPlayerController.currentPlaying
+
+            if (file != null) {
+                val song = file.song
+                val title = song.title
+                val artist = song.artist
+
+                imageLoader.getImageLoader().loadImage(
+                    nowPlayingAlbumArtImage,
+                    song,
+                    false,
+                    getNotificationImageSize(requireContext())
+                )
+
+                nowPlayingTrack!!.text = title
+                nowPlayingArtist!!.text = artist
+
+                nowPlayingAlbumArtImage!!.setOnClickListener {
+                    val bundle = Bundle()
+
+                    if (Settings.shouldUseId3Tags) {
+                        bundle.putBoolean(Constants.INTENT_EXTRA_NAME_IS_ALBUM, true)
+                        bundle.putString(Constants.INTENT_EXTRA_NAME_ID, song.albumId)
+                    } else {
+                        bundle.putBoolean(Constants.INTENT_EXTRA_NAME_IS_ALBUM, false)
+                        bundle.putString(Constants.INTENT_EXTRA_NAME_ID, song.parent)
+                    }
+
+                    bundle.putString(Constants.INTENT_EXTRA_NAME_NAME, song.album)
+                    bundle.putString(Constants.INTENT_EXTRA_NAME_NAME, song.album)
+
+                    Navigation.findNavController(requireActivity(), R.id.nav_host_fragment)
+                        .navigate(R.id.trackCollectionFragment, bundle)
+                }
+            }
+            requireView().setOnTouchListener { _: View?, event: MotionEvent ->
+                handleOnTouch(event)
+            }
+
+            // This empty onClickListener is necessary for the onTouchListener to work
+            requireView().setOnClickListener { }
+            playButton!!.setOnClickListener { mediaPlayerController.togglePlayPause() }
+        } catch (all: Exception) {
+            Timber.w(all, "Failed to get notification cover art")
+        }
+    }
+
+    private fun handleOnTouch(event: MotionEvent): Boolean {
+        when (event.action) {
+            MotionEvent.ACTION_DOWN -> {
+                downX = event.x
+                downY = event.y
+            }
+
+            MotionEvent.ACTION_UP -> {
+                val upX = event.x
+                val upY = event.y
+                val deltaX = downX - upX
+                val deltaY = downY - upY
+
+                if (abs(deltaX) > MIN_DISTANCE) {
+                    // left or right
+                    if (deltaX < 0) {
+                        mediaPlayerController.previous()
+                    }
+                    if (deltaX > 0) {
+                        mediaPlayerController.next()
+                    }
+                } else if (abs(deltaY) > MIN_DISTANCE) {
+                    if (deltaY < 0) {
+                        RxBus.dismissNowPlayingCommandPublisher.onNext(Unit)
+                    }
+                } else {
+                    Navigation.findNavController(requireActivity(), R.id.nav_host_fragment)
+                        .navigate(R.id.playerFragment)
+                }
+            }
+        }
+        return false
+    }
+
+    companion object {
+        private const val MIN_DISTANCE = 30
+    }
+}

ultrasonic/src/main/kotlin/org/moire/ultrasonic/service/AutoMediaBrowserService.kt

@@ -11,10 +11,9 @@ import android.os.Bundle
 import android.os.Handler
 import android.support.v4.media.MediaBrowserCompat
 import android.support.v4.media.MediaDescriptionCompat
-import android.support.v4.media.session.MediaSessionCompat
 import androidx.media.MediaBrowserServiceCompat
 import androidx.media.utils.MediaConstants
-import io.reactivex.rxjava3.disposables.Disposable
+import io.reactivex.rxjava3.disposables.CompositeDisposable
 import kotlinx.coroutines.CoroutineScope
 import kotlinx.coroutines.Dispatchers
 import kotlinx.coroutines.Job
@@ -26,8 +25,6 @@ import org.moire.ultrasonic.data.ActiveServerProvider
 import org.moire.ultrasonic.domain.MusicDirectory
 import org.moire.ultrasonic.domain.SearchCriteria
 import org.moire.ultrasonic.domain.SearchResult
-import org.moire.ultrasonic.util.MediaSessionEventDistributor
-import org.moire.ultrasonic.util.MediaSessionEventListener
 import org.moire.ultrasonic.util.MediaSessionHandler
 import org.moire.ultrasonic.util.Settings
 import org.moire.ultrasonic.util.Util
@@ -74,8 +71,6 @@ private const val SEARCH_LIMIT = 10
 @Suppress("TooManyFunctions", "LargeClass")
 class AutoMediaBrowserService : MediaBrowserServiceCompat() {
 
-    private lateinit var mediaSessionEventListener: MediaSessionEventListener
-    private val mediaSessionEventDistributor by inject<MediaSessionEventDistributor>()
     private val lifecycleSupport by inject<MediaPlayerLifecycleSupport>()
     private val mediaSessionHandler by inject<MediaSessionHandler>()
     private val mediaPlayerController by inject<MediaPlayerController>()
@@ -94,19 +89,44 @@ class AutoMediaBrowserService : MediaBrowserServiceCompat() {
     private val useId3Tags get() = Settings.shouldUseId3Tags
     private val musicFolderId get() = activeServerProvider.getActiveServer().musicFolderId
 
-    private var mediaSessionTokenSubscription: Disposable? = null
+    private var rxBusSubscription: CompositeDisposable = CompositeDisposable()
 
     @Suppress("MagicNumber")
     override fun onCreate() {
         super.onCreate()
 
-        mediaSessionTokenSubscription = RxBus.mediaSessionTokenObservable.subscribe {
+        rxBusSubscription += RxBus.mediaSessionTokenObservable.subscribe {
             if (sessionToken == null) sessionToken = it
         }
 
-        mediaSessionEventListener = object : MediaSessionEventListener {
+        rxBusSubscription += RxBus.playFromMediaIdCommandObservable.subscribe {
+            playFromMediaId(it.first)
+        }
 
-            override fun onPlayFromMediaIdRequested(mediaId: String?, extras: Bundle?) {
+        rxBusSubscription += RxBus.playFromSearchCommandObservable.subscribe {
+            playFromSearchCommand(it.first)
+        }
+
+        mediaSessionHandler.initialize()
+
+        val handler = Handler()
+        handler.postDelayed(
+            {
+                // Ultrasonic may be started from Android Auto. This boots up the necessary components.
+                Timber.d(
+                    "AutoMediaBrowserService starting lifecycleSupport and MediaPlayerService..."
+                )
+                lifecycleSupport.onCreate()
+                MediaPlayerService.getInstance()
+            },
+            100
+        )
+
+        Timber.i("AutoMediaBrowserService onCreate finished")
+    }
+
+    @Suppress("MagicNumber", "ComplexMethod")
+    private fun playFromMediaId(mediaId: String?) {
         Timber.d(
             "AutoMediaBrowserService onPlayFromMediaIdRequested called. mediaId: %s",
             mediaId
@@ -139,7 +159,7 @@ class AutoMediaBrowserService : MediaBrowserServiceCompat() {
         }
     }
 
-            override fun onPlayFromSearchRequested(query: String?, extras: Bundle?) {
+    private fun playFromSearchCommand(query: String?) {
         Timber.d("AutoMediaBrowserService onPlayFromSearchRequested query: %s", query)
         if (query.isNullOrBlank()) playRandomSongs()
 
@@ -161,31 +181,10 @@ class AutoMediaBrowserService : MediaBrowserServiceCompat() {
             }
         }
     }
-        }
-
-        mediaSessionEventDistributor.subscribe(mediaSessionEventListener)
-        mediaSessionHandler.initialize()
-
-        val handler = Handler()
-        handler.postDelayed(
-            {
-                // Ultrasonic may be started from Android Auto. This boots up the necessary components.
-                Timber.d(
-                    "AutoMediaBrowserService starting lifecycleSupport and MediaPlayerService..."
-                )
-                lifecycleSupport.onCreate()
-                MediaPlayerService.getInstance()
-            },
-            100
-        )
-
-        Timber.i("AutoMediaBrowserService onCreate finished")
-    }
 
     override fun onDestroy() {
         super.onDestroy()
-        mediaSessionTokenSubscription?.dispose()
+        rxBusSubscription.dispose()
-        mediaSessionEventDistributor.unsubscribe(mediaSessionEventListener)
         mediaSessionHandler.release()
         serviceJob.cancel()
 

ultrasonic/src/main/kotlin/org/moire/ultrasonic/service/Downloader.kt

@@ -31,6 +31,7 @@ class Downloader(
     private val localMediaPlayer: LocalMediaPlayer
 ) : KoinComponent {
     val playlist: MutableList<DownloadFile> = ArrayList()
+
     var started: Boolean = false
 
     private val downloadQueue: PriorityQueue<DownloadFile> = PriorityQueue<DownloadFile>()
@@ -46,7 +47,10 @@ class Downloader(
     private var wifiLock: WifiManager.WifiLock? = null
 
     var playlistUpdateRevision: Long = 0
-        private set
+        private set(value) {
+            field = value
+            RxBus.playlistPublisher.onNext(playlist)
+        }
 
     val downloadChecker = Runnable {
         try {
@@ -349,6 +353,20 @@ class Downloader(
         checkDownloads()
     }
 
+    @Synchronized
+    fun clearIncomplete() {
+        val iterator = playlist.iterator()
+        var changedPlaylist = false
+        while (iterator.hasNext()) {
+            val downloadFile = iterator.next()
+            if (!downloadFile.isCompleteFileAvailable) {
+                iterator.remove()
+                changedPlaylist = true
+            }
+        }
+        if (changedPlaylist) playlistUpdateRevision++
+    }
+
     @Synchronized
     fun downloadBackground(songs: List<MusicDirectory.Entry>, save: Boolean) {
 
@@ -429,18 +447,21 @@ class Downloader(
                 playlistUpdateRevision++
             }
         }
+
         if (revisionBefore != playlistUpdateRevision) {
             jukeboxMediaPlayer.updatePlaylist()
         }
+
         if (wasEmpty && playlist.isNotEmpty()) {
             if (jukeboxMediaPlayer.isEnabled) {
                 jukeboxMediaPlayer.skip(0, 0)
-                localMediaPlayer.setPlayerState(PlayerState.STARTED)
+                localMediaPlayer.setPlayerState(PlayerState.STARTED, playlist[0])
             } else {
                 localMediaPlayer.play(playlist[0])
             }
         }
     }
+
     companion object {
         const val PARALLEL_DOWNLOADS = 3
         const val CHECK_INTERVAL = 5L

ultrasonic/src/main/kotlin/org/moire/ultrasonic/service/LocalMediaPlayer.kt

@@ -32,7 +32,6 @@ import org.moire.ultrasonic.data.ActiveServerProvider.Companion.isOffline
 import org.moire.ultrasonic.domain.PlayerState
 import org.moire.ultrasonic.util.CancellableTask
 import org.moire.ultrasonic.util.Constants
-import org.moire.ultrasonic.util.MediaSessionHandler
 import org.moire.ultrasonic.util.Settings
 import org.moire.ultrasonic.util.StreamProxy
 import org.moire.ultrasonic.util.Util
@@ -46,17 +45,10 @@ class LocalMediaPlayer : KoinComponent {
 
     private val audioFocusHandler by inject<AudioFocusHandler>()
     private val context by inject<Context>()
-    private val mediaSessionHandler by inject<MediaSessionHandler>()
-
-    @JvmField
-    var onCurrentPlayingChanged: ((DownloadFile?) -> Unit?)? = null
 
     @JvmField
     var onSongCompleted: ((DownloadFile?) -> Unit?)? = null
 
-    @JvmField
-    var onPlayerStateChanged: ((PlayerState, DownloadFile?) -> Unit?)? = null
-
     @JvmField
     var onPrepared: (() -> Any?)? = null
 
@@ -64,6 +56,7 @@ class LocalMediaPlayer : KoinComponent {
     var onNextSongRequested: Runnable? = null
 
     @JvmField
+    @Volatile
     var playerState = PlayerState.IDLE
 
     @JvmField
@@ -132,7 +125,6 @@ class LocalMediaPlayer : KoinComponent {
         // Calling reset() will result in changing this player's state. If we allow
         // the onPlayerStateChanged callback, then the state change will cause this
         // to resurrect the media session which has just been destroyed.
-        onPlayerStateChanged = null
         reset()
         try {
             val i = Intent(AudioEffect.ACTION_CLOSE_AUDIO_EFFECT_CONTROL_SESSION)
@@ -164,21 +156,17 @@ class LocalMediaPlayer : KoinComponent {
     }
 
     @Synchronized
-    fun setPlayerState(playerState: PlayerState) {
+    fun setPlayerState(playerState: PlayerState, track: DownloadFile?) {
-        Timber.i("%s -> %s (%s)", this.playerState.name, playerState.name, currentPlaying)
+        Timber.i("%s -> %s (%s)", this.playerState.name, playerState.name, track)
+        synchronized(playerState) {
             this.playerState = playerState
+        }
         if (playerState === PlayerState.STARTED) {
             audioFocusHandler.requestAudioFocus()
         }
 
-        if (onPlayerStateChanged != null) {
+        RxBus.playerStatePublisher.onNext(RxBus.StateWithTrack(playerState, track))
-            val mainHandler = Handler(context.mainLooper)
 
-            val myRunnable = Runnable {
-                onPlayerStateChanged?.invoke(playerState, currentPlaying)
-            }
-            mainHandler.post(myRunnable)
-        }
         if (playerState === PlayerState.STARTED && positionCache == null) {
             positionCache = PositionCache()
             val thread = Thread(positionCache)
@@ -194,14 +182,10 @@ class LocalMediaPlayer : KoinComponent {
     */
     @Synchronized
     fun setCurrentPlaying(currentPlaying: DownloadFile?) {
-        Timber.v("setCurrentPlaying %s", currentPlaying)
+        // In some cases this function is called twice
+        if (this.currentPlaying == currentPlaying) return
         this.currentPlaying = currentPlaying
-
+        RxBus.currentPlayingPublisher.onNext(RxBus.StateWithTrack(playerState, currentPlaying))
-        if (onCurrentPlayingChanged != null) {
-            val mainHandler = Handler(context.mainLooper)
-            val myRunnable = Runnable { onCurrentPlayingChanged!!(currentPlaying) }
-            mainHandler.post(myRunnable)
-        }
     }
 
     /*
@@ -262,7 +246,7 @@ class LocalMediaPlayer : KoinComponent {
         mediaPlayer = nextMediaPlayer!!
 
         setCurrentPlaying(nextPlaying)
-        setPlayerState(PlayerState.STARTED)
+        setPlayerState(PlayerState.STARTED, currentPlaying)
 
         attachHandlersToPlayer(mediaPlayer, nextPlaying!!, false)
 
@@ -343,7 +327,7 @@ class LocalMediaPlayer : KoinComponent {
 
     @Synchronized
     private fun bufferAndPlay(fileToPlay: DownloadFile, position: Int, autoStart: Boolean) {
-        if (playerState !== PlayerState.PREPARED) {
+        if (playerState !== PlayerState.PREPARED && !fileToPlay.isWorkDone) {
             reset()
             bufferTask = BufferTask(fileToPlay, position, autoStart)
             bufferTask!!.start()
@@ -354,6 +338,7 @@ class LocalMediaPlayer : KoinComponent {
 
     @Synchronized
     private fun doPlay(downloadFile: DownloadFile, position: Int, start: Boolean) {
+        setPlayerState(PlayerState.IDLE, downloadFile)
 
         // In many cases we will be resetting the mediaPlayer a second time here.
         // figure out if we can remove this call...
@@ -368,7 +353,6 @@ class LocalMediaPlayer : KoinComponent {
             downloadFile.updateModificationDate()
             mediaPlayer.setOnCompletionListener(null)
 
-            setPlayerState(PlayerState.IDLE)
             setAudioAttributes(mediaPlayer)
 
             var dataSource = file.path
@@ -394,7 +378,7 @@ class LocalMediaPlayer : KoinComponent {
             Timber.i("Preparing media player")
 
             mediaPlayer.setDataSource(dataSource)
-            setPlayerState(PlayerState.PREPARING)
+            setPlayerState(PlayerState.PREPARING, downloadFile)
 
             mediaPlayer.setOnBufferingUpdateListener { mp, percent ->
                 val song = downloadFile.song
@@ -412,7 +396,7 @@ class LocalMediaPlayer : KoinComponent {
 
             mediaPlayer.setOnPreparedListener {
                 Timber.i("Media player prepared")
-                setPlayerState(PlayerState.PREPARED)
+                setPlayerState(PlayerState.PREPARED, downloadFile)
 
                 // Populate seek bar secondary progress if we have a complete file for consistency
                 if (downloadFile.isWorkDone) {
@@ -427,9 +411,9 @@ class LocalMediaPlayer : KoinComponent {
                     cachedPosition = position
                     if (start) {
                         mediaPlayer.start()
-                        setPlayerState(PlayerState.STARTED)
+                        setPlayerState(PlayerState.STARTED, downloadFile)
                     } else {
-                        setPlayerState(PlayerState.PAUSED)
+                        setPlayerState(PlayerState.PAUSED, downloadFile)
                     }
                 }
 
@@ -437,6 +421,7 @@ class LocalMediaPlayer : KoinComponent {
                     onPrepared
                 }
             }
+
             attachHandlersToPlayer(mediaPlayer, downloadFile, partial)
             mediaPlayer.prepareAsync()
         } catch (x: Exception) {
@@ -527,7 +512,7 @@ class LocalMediaPlayer : KoinComponent {
                 Timber.i("Ending position %d of %d", pos, duration)
 
                 if (!isPartial || downloadFile.isWorkDone && abs(duration - pos) < 1000) {
-                    setPlayerState(PlayerState.COMPLETED)
+                    setPlayerState(PlayerState.COMPLETED, downloadFile)
                     if (Settings.gaplessPlayback &&
                         nextPlaying != null &&
                         nextPlayerState === PlayerState.PREPARED
@@ -574,7 +559,7 @@ class LocalMediaPlayer : KoinComponent {
         resetMediaPlayer()
 
         try {
-            setPlayerState(PlayerState.IDLE)
+            setPlayerState(PlayerState.IDLE, currentPlaying)
             mediaPlayer.setOnErrorListener(null)
             mediaPlayer.setOnCompletionListener(null)
         } catch (x: Exception) {
@@ -603,7 +588,7 @@ class LocalMediaPlayer : KoinComponent {
         private val partialFile: File = downloadFile.partialFile
 
         override fun execute() {
-            setPlayerState(PlayerState.DOWNLOADING)
+            setPlayerState(PlayerState.DOWNLOADING, downloadFile)
             while (!bufferComplete() && !isOffline()) {
                 Util.sleepQuietly(1000L)
                 if (isCancelled) {
@@ -701,11 +686,13 @@ class LocalMediaPlayer : KoinComponent {
             // Stop checking position before the song reaches completion
             while (isRunning) {
                 try {
+                    if (playerState === PlayerState.STARTED) {
+                        synchronized(playerState) {
                             if (playerState === PlayerState.STARTED) {
                                 cachedPosition = mediaPlayer.currentPosition
-                        mediaSessionHandler.updateMediaSessionPlaybackPosition(
+                            }
-                            cachedPosition.toLong()
+                        }
-                        )
+                        RxBus.playbackPositionPublisher.onNext(cachedPosition)
                     }
                     Util.sleepQuietly(100L)
                 } catch (e: Exception) {

ultrasonic/src/main/kotlin/org/moire/ultrasonic/service/MediaPlayerController.kt

@@ -401,7 +401,8 @@ class MediaPlayerController(
         get() = localMediaPlayer.playerState
         set(state) {
             val mediaPlayerService = runningInstance
-            if (mediaPlayerService != null) localMediaPlayer.setPlayerState(state)
+            if (mediaPlayerService != null)
+                localMediaPlayer.setPlayerState(state, localMediaPlayer.currentPlaying)
         }
 
     @set:Synchronized
@@ -483,6 +484,7 @@ class MediaPlayerController(
                 Timber.e(e)
             }
         }.start()
+        // TODO this would be better handled with a Rx command
         updateNotification()
     }
 

ultrasonic/src/main/kotlin/org/moire/ultrasonic/service/MediaPlayerLifecycleSupport.kt

@@ -21,8 +21,6 @@ import org.moire.ultrasonic.app.UApp.Companion.applicationContext
 import org.moire.ultrasonic.domain.PlayerState
 import org.moire.ultrasonic.util.CacheCleaner
 import org.moire.ultrasonic.util.Constants
-import org.moire.ultrasonic.util.MediaSessionEventDistributor
-import org.moire.ultrasonic.util.MediaSessionEventListener
 import org.moire.ultrasonic.util.Settings
 import timber.log.Timber
 
@@ -35,7 +33,6 @@ class MediaPlayerLifecycleSupport : KoinComponent {
     private val playbackStateSerializer by inject<PlaybackStateSerializer>()
     private val mediaPlayerController by inject<MediaPlayerController>()
     private val downloader by inject<Downloader>()
-    private val mediaSessionEventDistributor by inject<MediaSessionEventDistributor>()
 
     private var created = false
     private var headsetEventReceiver: BroadcastReceiver? = null

ultrasonic/src/main/kotlin/org/moire/ultrasonic/service/MediaPlayerService.kt

@@ -22,7 +22,7 @@ import android.support.v4.media.session.MediaSessionCompat
 import android.view.KeyEvent
 import androidx.core.app.NotificationCompat
 import androidx.core.app.NotificationManagerCompat
-import io.reactivex.rxjava3.disposables.Disposable
+import io.reactivex.rxjava3.disposables.CompositeDisposable
 import kotlin.collections.ArrayList
 import org.koin.android.ext.android.inject
 import org.moire.ultrasonic.R
@@ -38,10 +38,7 @@ import org.moire.ultrasonic.provider.UltrasonicAppWidgetProvider4X3
 import org.moire.ultrasonic.provider.UltrasonicAppWidgetProvider4X4
 import org.moire.ultrasonic.service.MusicServiceFactory.getMusicService
 import org.moire.ultrasonic.util.Constants
-import org.moire.ultrasonic.util.MediaSessionEventDistributor
-import org.moire.ultrasonic.util.MediaSessionEventListener
 import org.moire.ultrasonic.util.MediaSessionHandler
-import org.moire.ultrasonic.util.NowPlayingEventDistributor
 import org.moire.ultrasonic.util.Settings
 import org.moire.ultrasonic.util.ShufflePlayBuffer
 import org.moire.ultrasonic.util.SimpleServiceBinder
@@ -65,19 +62,13 @@ class MediaPlayerService : Service() {
     private val shufflePlayBuffer by inject<ShufflePlayBuffer>()
     private val downloader by inject<Downloader>()
     private val localMediaPlayer by inject<LocalMediaPlayer>()
-    private val nowPlayingEventDistributor by inject<NowPlayingEventDistributor>()
-    private val mediaSessionEventDistributor by inject<MediaSessionEventDistributor>()
     private val mediaSessionHandler by inject<MediaSessionHandler>()
 
     private var mediaSession: MediaSessionCompat? = null
     private var mediaSessionToken: MediaSessionCompat.Token? = null
     private var isInForeground = false
     private var notificationBuilder: NotificationCompat.Builder? = null
-    private lateinit var mediaSessionEventListener: MediaSessionEventListener
+    private var rxBusSubscription: CompositeDisposable = CompositeDisposable()
-    private var mediaSessionTokenSubscription: Disposable? = null
-
-    private val repeatMode: RepeatMode
-        get() = Settings.repeatMode
 
     override fun onBind(intent: Intent): IBinder {
         return binder
@@ -89,8 +80,6 @@ class MediaPlayerService : Service() {
         shufflePlayBuffer.onCreate()
         localMediaPlayer.init()
 
-        setupOnCurrentPlayingChangedHandler()
-        setupOnPlayerStateChangedHandler()
         setupOnSongCompletedHandler()
 
         localMediaPlayer.onPrepared = {
@@ -104,25 +93,32 @@ class MediaPlayerService : Service() {
 
         localMediaPlayer.onNextSongRequested = Runnable { setNextPlaying() }
 
-        mediaSessionTokenSubscription = RxBus.mediaSessionTokenObservable.subscribe {
-            mediaSessionToken = it
-        }
-
-        mediaSessionEventListener = object : MediaSessionEventListener {
-            override fun onSkipToQueueItemRequested(id: Long) {
-                play(id.toInt())
-            }
-        }
-
-        mediaSessionEventDistributor.subscribe(mediaSessionEventListener)
-        mediaSessionHandler.initialize()
-
         // Create Notification Channel
         createNotificationChannel()
 
         // Update notification early. It is better to show an empty one temporarily
         // than waiting too long and letting Android kill the app
         updateNotification(PlayerState.IDLE, null)
+
+        // Subscribing should be after updateNotification to avoid concurrency
+        rxBusSubscription += RxBus.playerStateObservable.subscribe {
+            playerStateChangedHandler(it.state, it.track)
+        }
+
+        rxBusSubscription += RxBus.currentPlayingObservable.subscribe {
+            currentPlayingChangedHandler(it.state, it.track)
+        }
+
+        rxBusSubscription += RxBus.mediaSessionTokenObservable.subscribe {
+            mediaSessionToken = it
+        }
+
+        rxBusSubscription += RxBus.skipToQueueItemCommandObservable.subscribe {
+            play(it.toInt())
+        }
+
+        mediaSessionHandler.initialize()
+
         instance = this
         Timber.i("MediaPlayerService created")
     }
@@ -136,9 +132,8 @@ class MediaPlayerService : Service() {
         super.onDestroy()
         instance = null
         try {
-            mediaSessionTokenSubscription?.dispose()
-            mediaSessionEventDistributor.unsubscribe(mediaSessionEventListener)
             mediaSessionHandler.release()
+            rxBusSubscription.dispose()
 
             localMediaPlayer.release()
             downloader.stop()
@@ -211,9 +206,7 @@ class MediaPlayerService : Service() {
 
     @Synchronized
     fun setNextPlaying() {
-        val gaplessPlayback = Settings.gaplessPlayback
+        if (!Settings.gaplessPlayback) {
-
-        if (!gaplessPlayback) {
             localMediaPlayer.clearNextPlaying(true)
             return
         }
@@ -221,7 +214,7 @@ class MediaPlayerService : Service() {
         var index = downloader.currentPlayingIndex
 
         if (index != -1) {
-            when (repeatMode) {
+            when (Settings.repeatMode) {
                 RepeatMode.OFF -> index += 1
                 RepeatMode.ALL -> index = (index + 1) % downloader.playlist.size
                 RepeatMode.SINGLE -> {
@@ -293,7 +286,6 @@ class MediaPlayerService : Service() {
             if (start) {
                 if (jukeboxMediaPlayer.isEnabled) {
                     jukeboxMediaPlayer.skip(index, 0)
-                    localMediaPlayer.setPlayerState(PlayerState.STARTED)
                 } else {
                     localMediaPlayer.play(downloader.playlist[index])
                 }
@@ -321,7 +313,7 @@ class MediaPlayerService : Service() {
             } else {
                 localMediaPlayer.pause()
             }
-            localMediaPlayer.setPlayerState(PlayerState.PAUSED)
+            localMediaPlayer.setPlayerState(PlayerState.PAUSED, localMediaPlayer.currentPlaying)
         }
     }
 
@@ -334,7 +326,7 @@ class MediaPlayerService : Service() {
                 localMediaPlayer.pause()
             }
         }
-        localMediaPlayer.setPlayerState(PlayerState.STOPPED)
+        localMediaPlayer.setPlayerState(PlayerState.STOPPED, null)
     }
 
     @Synchronized
@@ -344,7 +336,7 @@ class MediaPlayerService : Service() {
         } else {
             localMediaPlayer.start()
         }
-        localMediaPlayer.setPlayerState(PlayerState.STARTED)
+        localMediaPlayer.setPlayerState(PlayerState.STARTED, localMediaPlayer.currentPlaying)
     }
 
     private fun updateWidget(playerState: PlayerState, song: MusicDirectory.Entry?) {
@@ -357,9 +349,10 @@ class MediaPlayerService : Service() {
         UltrasonicAppWidgetProvider4X4.getInstance().notifyChange(context, song, started, false)
     }
 
-    private fun setupOnCurrentPlayingChangedHandler() {
+    private fun currentPlayingChangedHandler(
-        localMediaPlayer.onCurrentPlayingChanged = { currentPlaying: DownloadFile? ->
+        playerState: PlayerState,
-
+        currentPlaying: DownloadFile?
+    ) {
         Util.broadcastNewTrackInfo(this@MediaPlayerService, currentPlaying?.song)
         Util.broadcastA2dpMetaDataChange(
             this@MediaPlayerService, playerPosition, currentPlaying,
@@ -367,39 +360,28 @@ class MediaPlayerService : Service() {
         )
 
         // Update widget
-            val playerState = localMediaPlayer.playerState
         val song = currentPlaying?.song
 
         updateWidget(playerState, song)
 
         if (currentPlaying != null) {
-                updateNotification(localMediaPlayer.playerState, currentPlaying)
+            updateNotification(playerState, currentPlaying)
-                nowPlayingEventDistributor.raiseShowNowPlayingEvent()
         } else {
-                nowPlayingEventDistributor.raiseHideNowPlayingEvent()
             stopForeground(true)
             isInForeground = false
             stopIfIdle()
         }
-            null
+
-        }
+        Timber.d("Processed currently playing track change")
     }
 
-    private fun setupOnPlayerStateChangedHandler() {
+    private fun playerStateChangedHandler(
-        localMediaPlayer.onPlayerStateChanged = {
         playerState: PlayerState,
         currentPlaying: DownloadFile?
-            ->
+    ) {
 
         val context = this@MediaPlayerService
 
-            // Notify MediaSession
-            mediaSessionHandler.updateMediaSession(
-                currentPlaying,
-                downloader.currentPlayingIndex.toLong(),
-                playerState
-            )
-
         if (playerState === PlayerState.PAUSED) {
             playbackStateSerializer.serialize(
                 downloader.playlist, downloader.currentPlayingIndex, playerPosition
@@ -426,10 +408,8 @@ class MediaPlayerService : Service() {
             // Only update notification if player state is one that will change the icon
             if (playerState === PlayerState.STARTED || playerState === PlayerState.PAUSED) {
                 updateNotification(playerState, currentPlaying)
-                    nowPlayingEventDistributor.raiseShowNowPlayingEvent()
             }
         } else {
-                nowPlayingEventDistributor.raiseHideNowPlayingEvent()
             stopForeground(true)
             isInForeground = false
             stopIfIdle()
@@ -440,9 +420,7 @@ class MediaPlayerService : Service() {
         } else if (playerState === PlayerState.COMPLETED) {
             scrobbler.scrobble(currentPlaying, true)
         }
-
+        Timber.d("Processed player state change")
-            null
-        }
     }
 
     private fun setupOnSongCompletedHandler() {
@@ -460,7 +438,7 @@ class MediaPlayerService : Service() {
                 }
             }
             if (index != -1) {
-                when (repeatMode) {
+                when (Settings.repeatMode) {
                     RepeatMode.OFF -> {
                         if (index + 1 < 0 || index + 1 >= downloader.playlist.size) {
                             if (Settings.shouldClearPlaylist) {

ultrasonic/src/main/kotlin/org/moire/ultrasonic/service/PlaybackStateSerializer.kt

@@ -19,7 +19,6 @@ import org.koin.core.component.KoinComponent
 import org.koin.core.component.inject
 import org.moire.ultrasonic.util.Constants
 import org.moire.ultrasonic.util.FileUtil
-import org.moire.ultrasonic.util.MediaSessionHandler
 import timber.log.Timber
 
 /**
@@ -30,9 +29,8 @@ import timber.log.Timber
 class PlaybackStateSerializer : KoinComponent {
 
     private val context by inject<Context>()
-    private val mediaSessionHandler by inject<MediaSessionHandler>()
 
-    val lock: Lock = ReentrantLock()
+    private val lock: Lock = ReentrantLock()
     private val setup = AtomicBoolean(false)
 
     private val appScope = CoroutineScope(SupervisorJob() + Dispatchers.IO)
@@ -76,9 +74,6 @@ class PlaybackStateSerializer : KoinComponent {
         )
 
         FileUtil.serialize(context, state, Constants.FILENAME_PLAYLIST_SER)
-
-        // This is called here because the queue is usually serialized after a change
-        mediaSessionHandler.updateMediaSessionQueue(state.songs)
     }
 
     fun deserialize(afterDeserialized: (State?) -> Unit?) {
@@ -106,7 +101,6 @@ class PlaybackStateSerializer : KoinComponent {
             state.currentPlayingPosition
         )
 
-        mediaSessionHandler.updateMediaSessionQueue(state.songs)
         afterDeserialized(state)
     }
 }

ultrasonic/src/main/kotlin/org/moire/ultrasonic/service/RxBus.kt

@@ -1,42 +1,93 @@
 package org.moire.ultrasonic.service
 
+import android.os.Bundle
 import android.support.v4.media.session.MediaSessionCompat
 import android.view.KeyEvent
-import io.reactivex.rxjava3.subjects.PublishSubject
 import io.reactivex.rxjava3.android.schedulers.AndroidSchedulers
 import io.reactivex.rxjava3.core.Observable
-import io.reactivex.rxjava3.observables.ConnectableObservable
+import io.reactivex.rxjava3.disposables.CompositeDisposable
-import timber.log.Timber
+import io.reactivex.rxjava3.disposables.Disposable
+import io.reactivex.rxjava3.subjects.PublishSubject
+import java.util.concurrent.TimeUnit
+import org.moire.ultrasonic.domain.PlayerState
 
-object RxBus {
+class RxBus {
+    companion object {
         var mediaSessionTokenPublisher: PublishSubject<MediaSessionCompat.Token> =
             PublishSubject.create()
         val mediaSessionTokenObservable: Observable<MediaSessionCompat.Token> =
             mediaSessionTokenPublisher.observeOn(AndroidSchedulers.mainThread())
                 .replay(1)
-            .autoConnect()
+                .autoConnect(0)
-            .doOnEach { Timber.d("RxBus mediaSessionTokenPublisher onEach $it")}
 
         val mediaButtonEventPublisher: PublishSubject<KeyEvent> =
             PublishSubject.create()
         val mediaButtonEventObservable: Observable<KeyEvent> =
             mediaButtonEventPublisher.observeOn(AndroidSchedulers.mainThread())
-            .doOnEach { Timber.d("RxBus mediaButtonEventPublisher onEach $it")}
 
         val themeChangedEventPublisher: PublishSubject<Unit> =
             PublishSubject.create()
         val themeChangedEventObservable: Observable<Unit> =
             themeChangedEventPublisher.observeOn(AndroidSchedulers.mainThread())
-            .doOnEach { Timber.d("RxBus themeChangedEventPublisher onEach $it")}
 
+        val playerStatePublisher: PublishSubject<StateWithTrack> =
+            PublishSubject.create()
+        val playerStateObservable: Observable<StateWithTrack> =
+            playerStatePublisher.observeOn(AndroidSchedulers.mainThread())
+                .replay(1)
+                .autoConnect(0)
+
+        val currentPlayingPublisher: PublishSubject<StateWithTrack> =
+            PublishSubject.create()
+        val currentPlayingObservable: Observable<StateWithTrack> =
+            currentPlayingPublisher.observeOn(AndroidSchedulers.mainThread())
+                .replay(1)
+                .autoConnect(0)
+
+        val playlistPublisher: PublishSubject<List<DownloadFile>> =
+            PublishSubject.create()
+        val playlistObservable: Observable<List<DownloadFile>> =
+            playlistPublisher.observeOn(AndroidSchedulers.mainThread())
+                .replay(1)
+                .autoConnect(0)
+
+        val playbackPositionPublisher: PublishSubject<Int> =
+            PublishSubject.create()
+        val playbackPositionObservable: Observable<Int> =
+            playbackPositionPublisher.observeOn(AndroidSchedulers.mainThread())
+                .throttleFirst(1, TimeUnit.SECONDS)
+                .replay(1)
+                .autoConnect(0)
+
+        // Commands
         val dismissNowPlayingCommandPublisher: PublishSubject<Unit> =
             PublishSubject.create()
         val dismissNowPlayingCommandObservable: Observable<Unit> =
             dismissNowPlayingCommandPublisher.observeOn(AndroidSchedulers.mainThread())
-            .doOnEach { Timber.d("RxBus dismissNowPlayingCommandPublisher onEach $it")}
 
-    fun releaseMediaSessionToken() { mediaSessionTokenPublisher = PublishSubject.create() }
+        val playFromMediaIdCommandPublisher: PublishSubject<Pair<String?, Bundle?>> =
+            PublishSubject.create()
+        val playFromMediaIdCommandObservable: Observable<Pair<String?, Bundle?>> =
+            playFromMediaIdCommandPublisher.observeOn(AndroidSchedulers.mainThread())
 
+        val playFromSearchCommandPublisher: PublishSubject<Pair<String?, Bundle?>> =
+            PublishSubject.create()
+        val playFromSearchCommandObservable: Observable<Pair<String?, Bundle?>> =
+            playFromSearchCommandPublisher.observeOn(AndroidSchedulers.mainThread())
+
+        val skipToQueueItemCommandPublisher: PublishSubject<Long> =
+            PublishSubject.create()
+        val skipToQueueItemCommandObservable: Observable<Long> =
+            skipToQueueItemCommandPublisher.observeOn(AndroidSchedulers.mainThread())
+
+        fun releaseMediaSessionToken() {
+            mediaSessionTokenPublisher = PublishSubject.create()
+        }
     }
 
+    data class StateWithTrack(val state: PlayerState, val track: DownloadFile?)
+}
 
+operator fun CompositeDisposable.plusAssign(disposable: Disposable) {
+    this.add(disposable)
+}

ultrasonic/src/main/kotlin/org/moire/ultrasonic/util/MediaSessionEventDistributor.kt

@@ -1,46 +0,0 @@
-/*
- * MediaSessionEventDistributor.kt
- * Copyright (C) 2009-2021 Ultrasonic developers
- *
- * Distributed under terms of the GNU GPLv3 license.
- */
-
-package org.moire.ultrasonic.util
-
-import android.os.Bundle
-import android.support.v4.media.session.MediaSessionCompat
-import android.view.KeyEvent
-
-/**
- * This class distributes MediaSession related events to its subscribers.
- * It is a primitive implementation of a pub-sub event bus
- */
-class MediaSessionEventDistributor {
-    var eventListenerList: MutableList<MediaSessionEventListener> =
-        listOf<MediaSessionEventListener>().toMutableList()
-
-    var cachedToken: MediaSessionCompat.Token? = null
-
-    fun subscribe(listener: MediaSessionEventListener) {
-        eventListenerList.add(listener)
-    }
-
-    fun unsubscribe(listener: MediaSessionEventListener) {
-        eventListenerList.remove(listener)
-    }
-
-    fun raisePlayFromMediaIdRequestedEvent(mediaId: String?, extras: Bundle?) {
-        eventListenerList.forEach {
-            listener ->
-            listener.onPlayFromMediaIdRequested(mediaId, extras)
-        }
-    }
-
-    fun raisePlayFromSearchRequestedEvent(query: String?, extras: Bundle?) {
-        eventListenerList.forEach { listener -> listener.onPlayFromSearchRequested(query, extras) }
-    }
-
-    fun raiseSkipToQueueItemRequestedEvent(id: Long) {
-        eventListenerList.forEach { listener -> listener.onSkipToQueueItemRequested(id) }
-    }
-}

ultrasonic/src/main/kotlin/org/moire/ultrasonic/util/MediaSessionEventListener.kt

@@ -1,23 +0,0 @@
-/*
- * MediaSessionEventListener.kt
- * Copyright (C) 2009-2021 Ultrasonic developers
- *
- * Distributed under terms of the GNU GPLv3 license.
- */
-
-package org.moire.ultrasonic.util
-
-import android.os.Bundle
-import android.support.v4.media.session.MediaSessionCompat
-import android.view.KeyEvent
-
-/**
- * Callback interface for MediaSession related event subscribers
- */
-interface MediaSessionEventListener {
-//    fun onMediaSessionTokenCreated(token: MediaSessionCompat.Token) {}
-    fun onPlayFromMediaIdRequested(mediaId: String?, extras: Bundle?) {}
-    fun onPlayFromSearchRequested(query: String?, extras: Bundle?) {}
-    fun onSkipToQueueItemRequested(id: Long) {}
-//    fun onMediaButtonEvent(keyEvent: KeyEvent?) {}
-}

ultrasonic/src/main/kotlin/org/moire/ultrasonic/util/MediaSessionHandler.kt

@@ -17,19 +17,20 @@ import android.support.v4.media.session.MediaSessionCompat
 import android.support.v4.media.session.PlaybackStateCompat
 import android.support.v4.media.session.PlaybackStateCompat.PLAYBACK_POSITION_UNKNOWN
 import android.view.KeyEvent
+import io.reactivex.rxjava3.disposables.CompositeDisposable
+import kotlin.Pair
 import org.koin.core.component.KoinComponent
 import org.koin.core.component.inject
 import org.moire.ultrasonic.R
-import org.moire.ultrasonic.domain.MusicDirectory
 import org.moire.ultrasonic.domain.PlayerState
 import org.moire.ultrasonic.imageloader.BitmapUtils
 import org.moire.ultrasonic.receiver.MediaButtonIntentReceiver
 import org.moire.ultrasonic.service.DownloadFile
 import org.moire.ultrasonic.service.RxBus
+import org.moire.ultrasonic.service.plusAssign
 import timber.log.Timber
 
 private const val INTENT_CODE_MEDIA_BUTTON = 161
-private const val CALL_DIVIDE = 10
 /**
  * Central place to handle the state of the MediaSession
  */
@@ -40,14 +41,14 @@ class MediaSessionHandler : KoinComponent {
     private var playbackActions: Long? = null
     private var cachedPlayingIndex: Long? = null
 
-    private val mediaSessionEventDistributor by inject<MediaSessionEventDistributor>()
     private val applicationContext by inject<Context>()
 
     private var referenceCount: Int = 0
-    private var cachedPlaylist: List<MediaSessionCompat.QueueItem>? = null
+    private var cachedPlaylist: List<DownloadFile>? = null
-    private var playbackPositionDelayCount: Int = 0
     private var cachedPosition: Long = 0
 
+    private val rxBusSubscription: CompositeDisposable = CompositeDisposable()
+
     fun release() {
 
         if (referenceCount > 0) referenceCount--
@@ -55,6 +56,7 @@ class MediaSessionHandler : KoinComponent {
 
         mediaSession?.isActive = false
         RxBus.releaseMediaSessionToken()
+        rxBusSubscription.dispose()
         mediaSession?.release()
         mediaSession = null
 
@@ -94,14 +96,14 @@ class MediaSessionHandler : KoinComponent {
                 super.onPlayFromMediaId(mediaId, extras)
 
                 Timber.d("Media Session Callback: onPlayFromMediaId %s", mediaId)
-                mediaSessionEventDistributor.raisePlayFromMediaIdRequestedEvent(mediaId, extras)
+                RxBus.playFromMediaIdCommandPublisher.onNext(Pair(mediaId, extras))
             }
 
             override fun onPlayFromSearch(query: String?, extras: Bundle?) {
                 super.onPlayFromSearch(query, extras)
 
                 Timber.d("Media Session Callback: onPlayFromSearch %s", query)
-                mediaSessionEventDistributor.raisePlayFromSearchRequestedEvent(query, extras)
+                RxBus.playFromSearchCommandPublisher.onNext(Pair(query, extras))
             }
 
             override fun onPause() {
@@ -154,22 +156,30 @@ class MediaSessionHandler : KoinComponent {
 
             override fun onSkipToQueueItem(id: Long) {
                 super.onSkipToQueueItem(id)
-                mediaSessionEventDistributor.raiseSkipToQueueItemRequestedEvent(id)
+                RxBus.skipToQueueItemCommandPublisher.onNext(id)
             }
         }
         )
 
         // It seems to be the best practice to set this to true for the lifetime of the session
         mediaSession?.isActive = true
-        if (cachedPlaylist != null) setMediaSessionQueue(cachedPlaylist)
+        rxBusSubscription += RxBus.playbackPositionObservable.subscribe {
+            updateMediaSessionPlaybackPosition(it)
+        }
+        rxBusSubscription += RxBus.playlistObservable.subscribe {
+            updateMediaSessionQueue(it)
+        }
+        rxBusSubscription += RxBus.playerStateObservable.subscribe {
+            updateMediaSession(it.state, it.track)
+        }
+
         Timber.i("MediaSessionHandler.initialize Media Session created")
     }
 
-    @Suppress("TooGenericExceptionCaught", "LongMethod")
+    @Suppress("LongMethod", "ComplexMethod")
-    fun updateMediaSession(
+    private fun updateMediaSession(
-        currentPlaying: DownloadFile?,
+        playerState: PlayerState,
-        currentPlayingIndex: Long?,
+        currentPlaying: DownloadFile?
-        playerState: PlayerState
     ) {
         Timber.d("Updating the MediaSession")
 
@@ -188,8 +198,8 @@ class MediaSessionHandler : KoinComponent {
                 metadata.putString(MediaMetadataCompat.METADATA_KEY_ALBUM, song.album)
                 metadata.putString(MediaMetadataCompat.METADATA_KEY_TITLE, song.title)
                 metadata.putBitmap(MediaMetadataCompat.METADATA_KEY_ALBUM_ART, cover)
-            } catch (e: Exception) {
+            } catch (all: Exception) {
-                Timber.e(e, "Error setting the metadata")
+                Timber.e(all, "Error setting the metadata")
             }
         }
 
@@ -245,52 +255,45 @@ class MediaSessionHandler : KoinComponent {
         // Set actions
         playbackStateBuilder.setActions(playbackActions!!)
 
-        cachedPlayingIndex = currentPlayingIndex
+        val index = cachedPlaylist?.indexOf(currentPlaying)
-        setMediaSessionQueue(cachedPlaylist)
+        cachedPlayingIndex = if (index == null || index < 0) null else index.toLong()
+        cachedPlaylist?.let { setMediaSessionQueue(it) }
+
         if (
-            currentPlayingIndex != null && cachedPlaylist != null &&
+            cachedPlayingIndex != null && cachedPlaylist != null &&
             !Settings.shouldDisableNowPlayingListSending
         )
-            playbackStateBuilder.setActiveQueueItemId(currentPlayingIndex)
+            cachedPlayingIndex?.let { playbackStateBuilder.setActiveQueueItemId(it) }
 
         // Save the playback state
         mediaSession?.setPlaybackState(playbackStateBuilder.build())
     }
 
-    fun updateMediaSessionQueue(playlist: Iterable<MusicDirectory.Entry>) {
+    private fun updateMediaSessionQueue(playlist: List<DownloadFile>) {
-        // This call is cached because Downloader may initialize earlier than the MediaSession
+        cachedPlaylist = playlist
-        cachedPlaylist = playlist.mapIndexed { id, song ->
+        setMediaSessionQueue(playlist)
-            MediaSessionCompat.QueueItem(
-                Util.getMediaDescriptionForEntry(song),
-                id.toLong()
-            )
-        }
-        setMediaSessionQueue(cachedPlaylist)
     }
 
-    private fun setMediaSessionQueue(queue: List<MediaSessionCompat.QueueItem>?) {
+    private fun setMediaSessionQueue(playlist: List<DownloadFile>) {
         if (mediaSession == null) return
         if (Settings.shouldDisableNowPlayingListSending) return
 
+        val queue = playlist.mapIndexed { id, file ->
+            MediaSessionCompat.QueueItem(
+                Util.getMediaDescriptionForEntry(file.song),
+                id.toLong()
+            )
+        }
         mediaSession?.setQueueTitle(applicationContext.getString(R.string.button_bar_now_playing))
         mediaSession?.setQueue(queue)
     }
 
-    fun updateMediaSessionPlaybackPosition(playbackPosition: Long) {
+    private fun updateMediaSessionPlaybackPosition(playbackPosition: Int) {
-
+        cachedPosition = playbackPosition.toLong()
-        cachedPosition = playbackPosition
-        if (mediaSession == null) return
-
         if (playbackState == null || playbackActions == null) return
 
-        // Playback position is updated too frequently in the player.
-        // This counter makes sure that the MediaSession is updated ~ at every second
-        playbackPositionDelayCount++
-        if (playbackPositionDelayCount < CALL_DIVIDE) return
-
-        playbackPositionDelayCount = 0
         val playbackStateBuilder = PlaybackStateCompat.Builder()
-        playbackStateBuilder.setState(playbackState!!, playbackPosition, 1.0f)
+        playbackStateBuilder.setState(playbackState!!, cachedPosition, 1.0f)
         playbackStateBuilder.setActions(playbackActions!!)
 
         if (

ultrasonic/src/main/kotlin/org/moire/ultrasonic/util/NowPlayingEventDistributor.kt

@@ -1,26 +0,0 @@
-package org.moire.ultrasonic.util
-
-/**
- * This class distributes Now Playing related events to its subscribers.
- * It is a primitive implementation of a pub-sub event bus
- */
-class NowPlayingEventDistributor {
-    private var eventListenerList: MutableList<NowPlayingEventListener> =
-        listOf<NowPlayingEventListener>().toMutableList()
-
-    fun subscribe(listener: NowPlayingEventListener) {
-        eventListenerList.add(listener)
-    }
-
-    fun unsubscribe(listener: NowPlayingEventListener) {
-        eventListenerList.remove(listener)
-    }
-
-    fun raiseShowNowPlayingEvent() {
-        eventListenerList.forEach { listener -> listener.onShowNowPlaying() }
-    }
-
-    fun raiseHideNowPlayingEvent() {
-        eventListenerList.forEach { listener -> listener.onHideNowPlaying() }
-    }
-}

ultrasonic/src/main/kotlin/org/moire/ultrasonic/util/NowPlayingEventListener.kt

@@ -1,9 +0,0 @@
-package org.moire.ultrasonic.util
-
-/**
- * Callback interface for Now Playing event subscribers
- */
-interface NowPlayingEventListener {
-    fun onHideNowPlaying()
-    fun onShowNowPlaying()
-}