replace first callbacks with mutablestate/shareflow

new-player/src/main/java/net/newpipe/newplayer/NewPlayer.kt

@@ -30,7 +30,14 @@ import androidx.media3.exoplayer.source.MediaSource
 import kotlinx.coroutines.CoroutineScope
 import kotlinx.coroutines.Dispatchers
 import kotlinx.coroutines.Job
+import kotlinx.coroutines.flow.MutableSharedFlow
+import kotlinx.coroutines.flow.MutableStateFlow
+import kotlinx.coroutines.flow.SharedFlow
+import kotlinx.coroutines.flow.StateFlow
+import kotlinx.coroutines.flow.asSharedFlow
+import kotlinx.coroutines.flow.update
 import kotlinx.coroutines.launch
+import net.newpipe.newplayer.model.UIModeState
 import net.newpipe.newplayer.utils.PlayList
 import kotlin.Exception
 
@@ -56,16 +63,13 @@ interface NewPlayer {
     var currentPosition: Long
     var fastSeekAmountSec: Int
     var playBackMode: PlayMode
-    var playMode: PlayMode?
+    var playMode : MutableStateFlow<PlayMode?>
 
     var playlist: PlayList
 
-    // calbacks
+    // callbacks
 
-    interface Listener {
-        fun playModeChange(playMode: PlayMode) {}
-        fun onError(exception: Exception) {}
-    }
+    val errorFlow : SharedFlow<Exception>
 
     // methods
     fun prepare()
@@ -74,7 +78,6 @@ interface NewPlayer {
     fun addToPlaylist(item: String)
     fun playStream(item: String, playMode: PlayMode)
     fun playStream(item: String, streamVariant: String, playMode: PlayMode)
-    fun addCallbackListener(listener: Listener?)
 
     data class Builder(val app: Application, val repository: MediaRepository) {
         private var mediaSourceFactory: MediaSource.Factory? = null
@@ -111,6 +114,9 @@ class NewPlayerImpl(
     override val repository: MediaRepository,
 ) : NewPlayer {
 
+    var mutableErrorFlow =  MutableSharedFlow<Exception>()
+    override val errorFlow = mutableErrorFlow.asSharedFlow()
+
     override val bufferedPercentage: Int
         get() = internalPlayer.bufferedPercentage
     override var currentPosition: Long
@@ -122,16 +128,9 @@ class NewPlayerImpl(
     override var fastSeekAmountSec: Int = 10
     override var playBackMode: PlayMode = PlayMode.EMBEDDED_VIDEO
 
-    private var callbackListener: ArrayList<NewPlayer.Listener?> = ArrayList()
     private var playerScope = CoroutineScope(Dispatchers.Default + Job())
 
-    override var playMode: PlayMode? = null
-        set(value) {
-            field = value
-            if (field != null) {
-                callbackListener.forEach { it?.playModeChange(field!!) }
-            }
-        }
+    override var playMode = MutableStateFlow<PlayMode?>(null)
 
     override var playWhenReady: Boolean
         set(value) {
@@ -154,9 +153,7 @@ class NewPlayerImpl(
                     if (newUri != null) {
                         TODO("Implement handing new uri on fixed error")
                     } else {
-                        callbackListener.forEach {
-                            it?.onError(error)
-                        }
+                        mutableErrorFlow.emit(error)
                     }
                 }
             }
@@ -204,7 +201,7 @@ class NewPlayerImpl(
         if (internalPlayer.playbackState == Player.STATE_IDLE) {
             internalPlayer.prepare()
         }
-        this.playMode = playMode
+        this.playMode.update { playMode }
     }
 
     private suspend fun toMediaItem(item: String, streamVariant: String): MediaItem {
@@ -232,13 +229,7 @@ class NewPlayerImpl(
             try {
                 task()
             } catch (e: Exception) {
-                callbackListener.forEach {
-                    it?.onError(e)
-                }
+                mutableErrorFlow.emit(e)
             }
         }
-
-    override fun addCallbackListener(listener: NewPlayer.Listener?) {
-        callbackListener.add(listener)
-    }
 }

new-player/src/main/java/net/newpipe/newplayer/utils/PlayList.kt

@@ -21,7 +21,9 @@
 
 package net.newpipe.newplayer.utils
 
+import androidx.media3.common.MediaMetadata
 import androidx.media3.common.Player
+import androidx.media3.common.Player.Listener
 
 
 // TODO: This is cool, but it might still contains all raceconditions since two actors are mutating the
@@ -32,6 +34,8 @@ import androidx.media3.common.Player
 // due to this reason some functions force the user to handle elements out of bounds exceptions.
 
 
+
+
 class PlayListIterator(
     val exoPlayer: Player,
     val fromIndex: Int,
@@ -83,6 +87,7 @@ class PlayList(val exoPlayer: Player, val fromIndex: Int = 0, val toIndex: Int =
     override val size: Int
         get() = minOf(exoPlayer.mediaItemCount, toIndex) - fromIndex
 
+    // TODO: This contains a race condition. When the player might change the playlist while this function runns
     override fun contains(element: String): Boolean {
         for (i in fromIndex..minOf(exoPlayer.mediaItemCount, toIndex)) {
             try {
@@ -95,6 +100,7 @@ class PlayList(val exoPlayer: Player, val fromIndex: Int = 0, val toIndex: Int =
         return false
     }
 
+    // TODO: This contains a race condition. When the player might change the playlist while this function runns
     override fun containsAll(elements: Collection<String>): Boolean {
         for (element in elements) {
             if (!this.contains(element)) {
@@ -106,10 +112,10 @@ class PlayList(val exoPlayer: Player, val fromIndex: Int = 0, val toIndex: Int =
 
     @Throws(IndexOutOfBoundsException::class)
     override fun get(index: Int) =
-        if (index < fromIndex || toIndex < index)
-            throw IndexOutOfBoundsException("Accessed playlist item outside of permitted Playlist ListWindow: $index")
+        if (index < 0 || toIndex < index + fromIndex)
+            throw IndexOutOfBoundsException("Accessed playlist item outside of permitted Playlist ListWindow: $index with [$fromIndex;$toIndex[")
         else
-            exoPlayer.getMediaItemAt(index).mediaId
+            exoPlayer.getMediaItemAt(index + fromIndex).mediaId
 
     override fun isEmpty() = exoPlayer.mediaItemCount == 0 || fromIndex == toIndex
 
@@ -127,20 +133,27 @@ class PlayList(val exoPlayer: Player, val fromIndex: Int = 0, val toIndex: Int =
         )
 
     override fun lastIndexOf(element: String): Int {
-        for (i in minOf(toIndex, exoPlayer.mediaItemCount) downTo fromIndex) {
-            try {
-                if (exoPlayer.getMediaItemAt(i).mediaId == element) {
-                    return i - fromIndex
-                }
-            } catch (e: IndexOutOfBoundsException) {
-                return -1
+        var mediaItemCount = 0
+        var newMediaItemCount =  minOf(toIndex, exoPlayer.mediaItemCount)
+
+        // this while loop is there to catch raceconditions
+        while(mediaItemCount != newMediaItemCount) {
+            mediaItemCount = newMediaItemCount
+            for (i in minOf(toIndex, exoPlayer.mediaItemCount) downTo fromIndex) {
+                try {
+                    if (exoPlayer.getMediaItemAt(i).mediaId == element) {
+                        return i - fromIndex
+                    }
+                } catch (_: IndexOutOfBoundsException) {}
+
             }
+            newMediaItemCount = minOf(toIndex, exoPlayer.mediaItemCount)
         }
         return -1
     }
 
     override fun indexOf(element: String): Int {
-        for (i in fromIndex.. minOf(toIndex, exoPlayer.mediaItemCount)) {
+        for (i in fromIndex..minOf(toIndex, exoPlayer.mediaItemCount)) {
             try {
                 if (exoPlayer.getMediaItemAt(i).mediaId == element) {
                     return i - fromIndex

test-app/src/main/java/net/newpipe/newplayer/testapp/MainActivity.kt

@@ -34,6 +34,7 @@ import androidx.media3.common.MediaItem
 import dagger.hilt.android.AndroidEntryPoint
 import net.newpipe.newplayer.ActivityBrainSlug
 import net.newpipe.newplayer.NewPlayer
+import net.newpipe.newplayer.PlayMode
 import net.newpipe.newplayer.VideoPlayerView
 import net.newpipe.newplayer.model.VideoPlayerViewModel
 import net.newpipe.newplayer.model.VideoPlayerViewModelImpl
@@ -63,7 +64,7 @@ class MainActivity : AppCompatActivity() {
 
         startStreamButton.setOnClickListener {
             newPlayer.playWhenReady = true
-            newPlayer.setStream(MediaItem.fromUri(getString(R.string.ccc_6502_video)))
+            newPlayer.playStream(getString(R.string.ccc_6502_video), PlayMode.EMBEDDED_VIDEO)
         }
 
         videoPlayerViewModel.newPlayer = newPlayer