playback: misc changes

I just spent 5 days trying to implement gapless playback using
ExoPlayer and Hopium. That's 5 days I'm never getting back. Heres
what I did add in the process though.

app/src/main/java/org/oxycblt/auxio/playback/PlaybackFragment.kt

@@ -131,10 +131,10 @@ class PlaybackFragment : Fragment() {
             binding.playbackSeekBar.setProgress(pos)
         }
 
-        playbackModel.nextItemsInQueue.observe(viewLifecycleOwner) {
+        playbackModel.nextUp.observe(viewLifecycleOwner) {
             // The queue icon uses a selector that will automatically tint the icon as active or
             // inactive. We just need to set the flag.
-            queueItem.isEnabled = playbackModel.nextItemsInQueue.value!!.isNotEmpty()
+            queueItem.isEnabled = playbackModel.nextUp.value!!.isNotEmpty()
         }
 
         playbackModel.isPlaying.observe(viewLifecycleOwner) { isPlaying ->

app/src/main/java/org/oxycblt/auxio/playback/PlaybackViewModel.kt

@@ -22,7 +22,6 @@ import android.content.Context
 import android.net.Uri
 import androidx.lifecycle.LiveData
 import androidx.lifecycle.MutableLiveData
-import androidx.lifecycle.Transformations
 import androidx.lifecycle.ViewModel
 import androidx.lifecycle.viewModelScope
 import kotlinx.coroutines.launch
@@ -50,17 +49,16 @@ class PlaybackViewModel : ViewModel(), PlaybackStateManager.Callback {
     // Playback
     private val mSong = MutableLiveData<Song?>()
     private val mParent = MutableLiveData<MusicParent?>()
-    private val mPosition = MutableLiveData(0L)
-
-    // Queue
-    private val mQueue = MutableLiveData(listOf<Song>())
-    private val mIndex = MutableLiveData(0)
-    private val mMode = MutableLiveData(PlaybackMode.ALL_SONGS)
 
     // States
     private val mIsPlaying = MutableLiveData(false)
     private val mIsShuffling = MutableLiveData(false)
     private val mLoopMode = MutableLiveData(LoopMode.NONE)
+    private val mPosition = MutableLiveData(0L)
+
+    // Queue
+    private val mNextUp = MutableLiveData(listOf<Song>())
+    private val mMode = MutableLiveData(PlaybackMode.ALL_SONGS)
 
     // Other
     private var mIntentUri: Uri? = null
@@ -69,23 +67,18 @@ class PlaybackViewModel : ViewModel(), PlaybackStateManager.Callback {
     val song: LiveData<Song?> get() = mSong
     /** The current model that is being played from, such as an [Album] or [Artist] */
     val parent: LiveData<MusicParent?> get() = mParent
-    /** The current playback position, in seconds */
-    val position: LiveData<Long> get() = mPosition
-
-    /** The current queue determined by [playbackMode] and [parent] */
-    val queue: LiveData<List<Song>> get() = mQueue
-    /** The current [PlaybackMode] that also determines the queue */
-    val playbackMode: LiveData<PlaybackMode> get() = mMode
 
     val isPlaying: LiveData<Boolean> get() = mIsPlaying
     val isShuffling: LiveData<Boolean> get() = mIsShuffling
     /** The current repeat mode, see [LoopMode] for more information */
     val loopMode: LiveData<LoopMode> get() = mLoopMode
+    /** The current playback position, in seconds */
+    val position: LiveData<Long> get() = mPosition
 
     /** The queue, without the previous items. */
-    val nextItemsInQueue = Transformations.map(queue) { queue ->
-        queue.slice((mIndex.value!! + 1) until queue.size)
-    }
+    val nextUp: LiveData<List<Song>> get() = mNextUp
+    /** The current [PlaybackMode] that also determines the queue */
+    val playbackMode: LiveData<PlaybackMode> get() = mMode
 
     private val playbackManager = PlaybackStateManager.maybeGetInstance()
     private val settingsManager = SettingsManager.getInstance()
@@ -220,9 +213,9 @@ class PlaybackViewModel : ViewModel(), PlaybackStateManager.Callback {
      * [apply] is called just before the change is committed so that the adapter can be updated.
      */
     fun removeQueueDataItem(adapterIndex: Int, apply: () -> Unit) {
-        val adjusted = adapterIndex + (mQueue.value!!.size - nextItemsInQueue.value!!.size)
+        val adjusted = adapterIndex + (playbackManager.queue.size - mNextUp.value!!.size)
 
-        if (adjusted in mQueue.value!!.indices) {
+        if (adjusted in mNextUp.value!!.indices) {
             apply()
             playbackManager.removeQueueItem(adjusted)
         }
@@ -232,12 +225,12 @@ class PlaybackViewModel : ViewModel(), PlaybackStateManager.Callback {
      * [apply] is called just before the change is committed so that the adapter can be updated.
      */
     fun moveQueueDataItems(adapterFrom: Int, adapterTo: Int, apply: () -> Unit): Boolean {
-        val delta = (mQueue.value!!.size - nextItemsInQueue.value!!.size)
+        val delta = (playbackManager.queue.size - mNextUp.value!!.size)
 
         val from = adapterFrom + delta
         val to = adapterTo + delta
 
-        if (from in mQueue.value!!.indices && to in mQueue.value!!.indices) {
+        if (from in mNextUp.value!!.indices && to in mNextUp.value!!.indices) {
             apply()
             playbackManager.moveQueueItems(from, to)
             return true
@@ -287,7 +280,7 @@ class PlaybackViewModel : ViewModel(), PlaybackStateManager.Callback {
      * Flip the shuffle status, e.g from on to off. Will keep song by default.
      */
     fun invertShuffleStatus() {
-        playbackManager.setShuffling(!playbackManager.isShuffling, keepSong = true)
+        playbackManager.setShuffling(!playbackManager.isShuffling, true)
     }
 
     /**
@@ -343,9 +336,8 @@ class PlaybackViewModel : ViewModel(), PlaybackStateManager.Callback {
         mSong.value = playbackManager.song
         mPosition.value = playbackManager.position / 1000
         mParent.value = playbackManager.parent
-        mQueue.value = playbackManager.queue
+        mNextUp.value = playbackManager.queue
         mMode.value = playbackManager.playbackMode
-        mIndex.value = playbackManager.index
         mIsPlaying.value = playbackManager.isPlaying
         mIsShuffling.value = playbackManager.isShuffling
         mLoopMode.value = playbackManager.loopMode
@@ -369,12 +361,8 @@ class PlaybackViewModel : ViewModel(), PlaybackStateManager.Callback {
         mPosition.value = position / 1000
     }
 
-    override fun onQueueUpdate(queue: List<Song>) {
-        mQueue.value = queue
-    }
-
-    override fun onIndexUpdate(index: Int) {
-        mIndex.value = index
+    override fun onQueueUpdate(queue: List<Song>, index: Int) {
+        mNextUp.value = queue.slice(index.inc() until queue.size)
     }
 
     override fun onModeUpdate(mode: PlaybackMode) {

app/src/main/java/org/oxycblt/auxio/playback/queue/QueueFragment.kt

@@ -67,7 +67,7 @@ class QueueFragment : Fragment() {
 
         // --- VIEWMODEL SETUP ----
 
-        playbackModel.nextItemsInQueue.observe(viewLifecycleOwner) { queue ->
+        playbackModel.nextUp.observe(viewLifecycleOwner) { queue ->
             if (queue.isEmpty()) {
                 findNavController().navigateUp()
                 return@observe

app/src/main/java/org/oxycblt/auxio/playback/state/PlaybackStateManager.kt

@@ -63,15 +63,7 @@ class PlaybackStateManager private constructor() {
 
     // Queue
     private var mQueue = mutableListOf<Song>()
-        set(value) {
-            field = value
-            callbacks.forEach { it.onQueueUpdate(value) }
-        }
     private var mIndex = 0
-        set(value) {
-            field = value
-            callbacks.forEach { it.onIndexUpdate(value) }
-        }
     private var mPlaybackMode = PlaybackMode.ALL_SONGS
         set(value) {
             field = value
@@ -107,8 +99,6 @@ class PlaybackStateManager private constructor() {
     val position: Long get() = mPosition
     /** The current queue determined by [parent] and [playbackMode] */
     val queue: List<Song> get() = mQueue
-    /** The current index of the queue */
-    val index: Int get() = mIndex
     /** The current [PlaybackMode] */
     val playbackMode: PlaybackMode get() = mPlaybackMode
     /** Whether playback is paused or not */
@@ -263,7 +253,7 @@ class PlaybackStateManager private constructor() {
             updatePlayback(mQueue[mIndex], shouldPlay = mLoopMode == LoopMode.ALL)
         }
 
-        forceQueueUpdate()
+        pushQueueUpdate()
     }
 
     /**
@@ -280,7 +270,7 @@ class PlaybackStateManager private constructor() {
             }
 
             updatePlayback(mQueue[mIndex])
-            forceQueueUpdate()
+            pushQueueUpdate()
         }
     }
 
@@ -300,7 +290,7 @@ class PlaybackStateManager private constructor() {
 
         mQueue.removeAt(index)
 
-        forceQueueUpdate()
+        pushQueueUpdate()
 
         return true
     }
@@ -318,7 +308,7 @@ class PlaybackStateManager private constructor() {
         val item = mQueue.removeAt(from)
         mQueue.add(to, item)
 
-        forceQueueUpdate()
+        pushQueueUpdate()
 
         return true
     }
@@ -328,7 +318,7 @@ class PlaybackStateManager private constructor() {
      */
     fun playNext(song: Song) {
         mQueue.add(min(mIndex + 1, max(mQueue.lastIndex, 0)), song)
-        forceQueueUpdate()
+        pushQueueUpdate()
     }
 
     /**
@@ -336,7 +326,7 @@ class PlaybackStateManager private constructor() {
      */
     fun playNext(songs: List<Song>) {
         mQueue.addAll(min(mIndex + 1, max(mQueue.lastIndex, 0)), songs)
-        forceQueueUpdate()
+        pushQueueUpdate()
     }
 
     /**
@@ -344,7 +334,7 @@ class PlaybackStateManager private constructor() {
      */
     fun addToQueue(song: Song) {
         mQueue.add(song)
-        forceQueueUpdate()
+        pushQueueUpdate()
     }
 
     /**
@@ -352,14 +342,16 @@ class PlaybackStateManager private constructor() {
      */
     fun addToQueue(songs: List<Song>) {
         mQueue.addAll(songs)
-        forceQueueUpdate()
+        pushQueueUpdate()
     }
 
     /**
      * Force any callbacks to receive a queue update.
      */
-    private fun forceQueueUpdate() {
-        mQueue = mQueue
+    private fun pushQueueUpdate() {
+        callbacks.forEach {
+            it.onQueueUpdate(mQueue, mIndex)
+        }
     }
 
     // --- SHUFFLE FUNCTIONS ---
@@ -398,7 +390,7 @@ class PlaybackStateManager private constructor() {
             mSong = mQueue[0]
         }
 
-        forceQueueUpdate()
+        pushQueueUpdate()
     }
 
     /**
@@ -424,7 +416,7 @@ class PlaybackStateManager private constructor() {
             mIndex = mQueue.indexOf(lastSong)
         }
 
-        forceQueueUpdate()
+        pushQueueUpdate()
     }
 
     // --- STATE FUNCTIONS ---
@@ -603,7 +595,7 @@ class PlaybackStateManager private constructor() {
             }
         }
 
-        forceQueueUpdate()
+        pushQueueUpdate()
     }
 
     /**
@@ -632,9 +624,8 @@ class PlaybackStateManager private constructor() {
         fun onSongUpdate(song: Song?) {}
         fun onParentUpdate(parent: MusicParent?) {}
         fun onPositionUpdate(position: Long) {}
-        fun onQueueUpdate(queue: List<Song>) {}
+        fun onQueueUpdate(queue: List<Song>, index: Int) {}
         fun onModeUpdate(mode: PlaybackMode) {}
-        fun onIndexUpdate(index: Int) {}
         fun onPlayingUpdate(isPlaying: Boolean) {}
         fun onShuffleUpdate(isShuffling: Boolean) {}
         fun onLoopUpdate(loopMode: LoopMode) {}

app/src/main/java/org/oxycblt/auxio/playback/system/PlaybackService.kt

@@ -29,7 +29,6 @@ import android.content.pm.ServiceInfo
 import android.media.AudioManager
 import android.os.Build
 import android.os.IBinder
-import android.os.PowerManager
 import android.support.v4.media.session.MediaSessionCompat
 import com.google.android.exoplayer2.C
 import com.google.android.exoplayer2.ExoPlayer
@@ -87,7 +86,6 @@ class PlaybackService : Service(), Player.Listener, PlaybackStateManager.Callbac
 
     // System backend components
     private lateinit var audioReactor: AudioReactor
-    private lateinit var wakeLock: PowerManager.WakeLock
     private lateinit var widgets: WidgetController
     private val systemReceiver = SystemEventReceiver()
 
@@ -131,10 +129,6 @@ class PlaybackService : Service(), Player.Listener, PlaybackStateManager.Callbac
         // --- SYSTEM SETUP ---
 
         audioReactor = AudioReactor(this, player)
-        wakeLock = getSystemServiceSafe(PowerManager::class).newWakeLock(
-            PowerManager.PARTIAL_WAKE_LOCK, this::class.simpleName
-        )
-
         widgets = WidgetController(this)
 
         // Set up the media button callbacks
@@ -195,7 +189,6 @@ class PlaybackService : Service(), Player.Listener, PlaybackStateManager.Callbac
         mediaSession.release()
         audioReactor.release()
         widgets.release()
-        releaseWakelock()
 
         playbackManager.removeCallback(this)
         settingsManager.removeCallback(this)
@@ -216,10 +209,7 @@ class PlaybackService : Service(), Player.Listener, PlaybackStateManager.Callbac
 
     override fun onPlaybackStateChanged(state: Int) {
         when (state) {
-            Player.STATE_READY -> {
-                startPollingPosition()
-                releaseWakelock()
-            }
+            Player.STATE_READY -> startPollingPosition()
 
             Player.STATE_ENDED -> {
                 if (playbackManager.loopMode == LoopMode.TRACK) {
@@ -233,11 +223,6 @@ class PlaybackService : Service(), Player.Listener, PlaybackStateManager.Callbac
         }
     }
 
-    override fun onMediaItemTransition(mediaItem: MediaItem?, reason: Int) {
-        // We use the wakelock to ensure that the CPU is active while music is being loaded
-        acquireWakeLock()
-    }
-
     override fun onPlayerError(error: PlaybackException) {
         // If there's any issue, just go to the next song.
         playbackManager.next()
@@ -357,6 +342,7 @@ class PlaybackService : Service(), Player.Listener, PlaybackStateManager.Callbac
 
         return ExoPlayer.Builder(this, audioRenderer)
             .setMediaSourceFactory(DefaultMediaSourceFactory(this, extractorsFactory))
+            .setWakeMode(C.WAKE_MODE_LOCAL)
             .build()
     }
 
@@ -434,26 +420,6 @@ class PlaybackService : Service(), Player.Listener, PlaybackStateManager.Callbac
         isForeground = false
     }
 
-    /**
-     * Hold the wakelock for the default amount of time [25 Seconds]
-     */
-    private fun acquireWakeLock() {
-        wakeLock.acquire(WAKELOCK_TIME)
-
-        logD("Wakelock is held.")
-    }
-
-    /**
-     * Release the wakelock if its currently being held.
-     */
-    private fun releaseWakelock() {
-        if (wakeLock.isHeld) {
-            wakeLock.release()
-
-            logD("Wakelock is released.")
-        }
-    }
-
     /**
      * A [BroadcastReceiver] for receiving system events from notifications, widgets, or
      * headset plug events.

info/ADDITIONS.md

@@ -21,9 +21,12 @@ This does not rule out these additions, but they are not accepted as often as ot
 
 Feel free to fork Auxio to add your own feature set however.
 
-#### Additions that have already been rejected:
-- ReplayGain [#7]
-- Folder View/Grouping [#10]
-- Recently added list [#18]
-- Lyrics [#19]
-- Tag editing [#33]
+#### Additions that have already been rejected (and why):
+
+- Folder View/Grouping [#10] (Out of scope)
+- Recently added list [#18] (Out of scope)
+- Lyrics [#19] (Out of scope)
+- Tag editing [#33] (Out of scope)
+- Gapless Playback [#35] (Technical issues)
+- Reduce leading instrument [#45] (Technical issues, Out of scope)
+- Opening music through a provider [#30] (Out of scope)