-Fixed incorrect stream from being played after consecutive player errors.

-Fixed MediaSource reuse due to MediaSourceManager not resetting source on block.

app/src/main/java/org/schabi/newpipe/player/BackgroundPlayer.java

@@ -32,6 +32,7 @@ import android.os.Build;
 import android.os.IBinder;
 import android.os.PowerManager;
 import android.support.annotation.IntRange;
+import android.support.annotation.NonNull;
 import android.support.annotation.Nullable;
 import android.support.v4.app.NotificationCompat;
 import android.util.Log;
@@ -49,6 +50,7 @@ import org.schabi.newpipe.extractor.MediaFormat;
 import org.schabi.newpipe.extractor.StreamingService;
 import org.schabi.newpipe.extractor.stream.AudioStream;
 import org.schabi.newpipe.extractor.stream.StreamInfo;
+import org.schabi.newpipe.playlist.PlayQueueItem;
 import org.schabi.newpipe.util.Constants;
 import org.schabi.newpipe.util.ListHelper;
 import org.schabi.newpipe.util.ThemeHelper;
@@ -346,7 +348,7 @@ public final class BackgroundPlayer extends Service {
         public void onUpdateProgress(int currentProgress, int duration, int bufferPercent) {
             resetNotification();
             if (bigNotRemoteView != null) {
-                if (currentInfo != null) {
+                if (currentItem != null) {
                     bigNotRemoteView.setTextViewText(R.id.notificationSongName, getVideoTitle());
                     bigNotRemoteView.setTextViewText(R.id.notificationArtist, getUploaderName());
                 }
@@ -354,7 +356,7 @@ public final class BackgroundPlayer extends Service {
                 bigNotRemoteView.setTextViewText(R.id.notificationTime, getTimeString(currentProgress) + " / " + getTimeString(duration));
             }
             if (notRemoteView != null) {
-                if (currentInfo != null) {
+                if (currentItem != null) {
                     notRemoteView.setTextViewText(R.id.notificationSongName, getVideoTitle());
                     notRemoteView.setTextViewText(R.id.notificationArtist, getUploaderName());
                 }
@@ -442,8 +444,8 @@ public final class BackgroundPlayer extends Service {
         //////////////////////////////////////////////////////////////////////////*/
 
         @Override
-        public void sync(@Nullable final StreamInfo info) {
+        public void sync(@NonNull final PlayQueueItem item, @Nullable final StreamInfo info) {
-            super.sync(info);
+            super.sync(item, info);
 
             resetNotification();
             notRemoteView.setTextViewText(R.id.notificationSongName, getVideoTitle());

app/src/main/java/org/schabi/newpipe/player/BasePlayer.java

@@ -79,6 +79,7 @@ import org.schabi.newpipe.player.playback.MediaSourceManager;
 import org.schabi.newpipe.player.playback.PlaybackListener;
 import org.schabi.newpipe.playlist.PlayQueue;
 import org.schabi.newpipe.playlist.PlayQueueAdapter;
+import org.schabi.newpipe.playlist.PlayQueueItem;
 
 import java.io.File;
 import java.io.Serializable;
@@ -149,6 +150,7 @@ public abstract class BasePlayer implements Player.EventListener,
     private long videoPos = -1;
 
     protected StreamInfo currentInfo;
+    protected PlayQueueItem currentItem;
 
     /*//////////////////////////////////////////////////////////////////////////
     // Player
@@ -729,23 +731,27 @@ public abstract class BasePlayer implements Player.EventListener,
         if (getCurrentState() == STATE_BLOCKED) changeState(STATE_BUFFERING);
 
         simpleExoPlayer.prepare(mediaSource);
+        simpleExoPlayer.seekToDefaultPosition();
     }
 
     @Override
-    public void sync(@Nullable final StreamInfo info) {
+    public void sync(@android.support.annotation.NonNull final PlayQueueItem item,
-        if (info == null || simpleExoPlayer == null) return;
+                     @Nullable final StreamInfo info) {
+        if (simpleExoPlayer == null) return;
         if (DEBUG) Log.d(TAG, "Syncing...");
 
+        currentItem = item;
+        currentInfo = info;
+
         // Check if on wrong window
         final int currentSourceIndex = playQueue.getIndex();
-        if (!(simpleExoPlayer.getCurrentWindowIndex() == currentSourceIndex)) {
+        if (simpleExoPlayer.getCurrentWindowIndex() != currentSourceIndex) {
-            final long startPos = currentInfo != null ? currentInfo.start_position : 0;
+            final long startPos = info != null ? info.start_position : 0;
             if (DEBUG) Log.d(TAG, "Rewinding to correct window: " + currentSourceIndex + " at: " + getTimeString((int)startPos));
             simpleExoPlayer.seekTo(currentSourceIndex, startPos);
         }
 
-        currentInfo = info;
+        initThumbnail(info == null ? item.getThumbnailUrl() : info.thumbnail_url);
-        initThumbnail(info.thumbnail_url);
     }
 
     @Override
@@ -797,13 +803,14 @@ public abstract class BasePlayer implements Player.EventListener,
     }
 
     public void onPlayPrevious() {
-        if (simpleExoPlayer == null || playQueue == null || currentInfo == null) return;
+        if (simpleExoPlayer == null || playQueue == null) return;
         if (DEBUG) Log.d(TAG, "onPlayPrevious() called");
 
         /* If current playback has run for PLAY_PREV_ACTIVATION_LIMIT milliseconds, restart current track.
         * Also restart the track if the current track is the first in a queue.*/
         if (simpleExoPlayer.getCurrentPosition() > PLAY_PREV_ACTIVATION_LIMIT || playQueue.getIndex() == 0) {
-            simpleExoPlayer.seekTo(currentInfo.start_position);
+            final long startPos = currentInfo == null ? 0 : currentInfo.start_position;
+            simpleExoPlayer.seekTo(startPos);
         } else {
             playQueue.offsetIndex(-1);
         }
@@ -947,15 +954,15 @@ public abstract class BasePlayer implements Player.EventListener,
     }
 
     public String getVideoUrl() {
-        return currentInfo == null ? null : currentInfo.url;
+        return currentItem == null ? null : currentItem.getUrl();
     }
 
     public String getVideoTitle() {
-        return currentInfo == null ? null : currentInfo.name;
+        return currentItem == null ? null : currentItem.getTitle();
     }
 
     public String getUploaderName() {
-        return currentInfo == null ? null : currentInfo.uploader_name;
+        return currentItem == null ? null : currentItem.getUploader();
     }
 
     public boolean isCompleted() {

app/src/main/java/org/schabi/newpipe/player/MainVideoPlayer.java

@@ -26,6 +26,7 @@ import android.graphics.Color;
 import android.media.AudioManager;
 import android.os.Build;
 import android.os.Bundle;
+import android.support.annotation.NonNull;
 import android.support.annotation.Nullable;
 import android.util.Log;
 import android.view.GestureDetector;
@@ -43,6 +44,7 @@ import com.google.android.exoplayer2.trackselection.DefaultTrackSelector;
 
 import org.schabi.newpipe.R;
 import org.schabi.newpipe.extractor.stream.StreamInfo;
+import org.schabi.newpipe.playlist.PlayQueueItem;
 import org.schabi.newpipe.util.AnimationUtils;
 import org.schabi.newpipe.util.NavigationHelper;
 import org.schabi.newpipe.util.PermissionHelper;
@@ -250,8 +252,8 @@ public final class MainVideoPlayer extends Activity {
         }
 
         @Override
-        public void sync(@Nullable final StreamInfo info) {
+        public void sync(@NonNull final PlayQueueItem item, @Nullable final StreamInfo info) {
-            super.sync(info);
+            super.sync(item, info);
             titleTextView.setText(getVideoTitle());
             channelTextView.setText(getUploaderName());
 

app/src/main/java/org/schabi/newpipe/player/VideoPlayer.java

@@ -31,6 +31,7 @@ import android.graphics.Color;
 import android.graphics.PorterDuff;
 import android.os.Build;
 import android.os.Handler;
+import android.support.annotation.NonNull;
 import android.support.annotation.Nullable;
 import android.support.v4.content.ContextCompat;
 import android.util.Log;
@@ -64,6 +65,7 @@ import org.schabi.newpipe.R;
 import org.schabi.newpipe.extractor.MediaFormat;
 import org.schabi.newpipe.extractor.stream.StreamInfo;
 import org.schabi.newpipe.extractor.stream.VideoStream;
+import org.schabi.newpipe.playlist.PlayQueueItem;
 import org.schabi.newpipe.util.AnimationUtils;
 import org.schabi.newpipe.util.ListHelper;
 
@@ -304,8 +306,8 @@ public abstract class VideoPlayer extends BasePlayer implements SimpleExoPlayer.
     //////////////////////////////////////////////////////////////////////////*/
 
     @Override
-    public void sync(@Nullable final StreamInfo info) {
+    public void sync(@NonNull final PlayQueueItem item, @Nullable final StreamInfo info) {
-        super.sync(info);
+        super.sync(item, info);
 
         if (info != null) {
             final List<VideoStream> videos = ListHelper.getSortedStreamVideosList(context, info.video_streams, info.video_only_streams, false);

app/src/main/java/org/schabi/newpipe/player/playback/MediaSourceManager.java

@@ -29,7 +29,7 @@ import io.reactivex.functions.Consumer;
 public class MediaSourceManager implements DeferredMediaSource.Callback {
     private final String TAG = "MediaSourceManager@" + Integer.toHexString(hashCode());
     // One-side rolling window size for default loading
-    // Effectively loads WINDOW_SIZE * 2 + 1 streams, should be at least 1 to ensure gapless playback
+    // Effectively loads WINDOW_SIZE * 2 + 1 streams, must be greater than 0
     // todo: inject this parameter, allow user settings perhaps
     private static final int WINDOW_SIZE = 1;
 
@@ -116,7 +116,6 @@ public class MediaSourceManager implements DeferredMediaSource.Callback {
      * */
     public void reset() {
         tryBlock();
-        resetSources();
         populateSources();
     }
 
@@ -149,6 +148,10 @@ public class MediaSourceManager implements DeferredMediaSource.Callback {
     private void onPlayQueueChanged(final PlayQueueMessage event) {
         // why no pattern matching in Java =(
         switch (event.type()) {
+            case INIT:
+            case REORDER:
+                reset();
+                break;
             case APPEND:
                 populateSources();
                 break;
@@ -159,10 +162,6 @@ public class MediaSourceManager implements DeferredMediaSource.Callback {
                 final RemoveEvent removeEvent = (RemoveEvent) event;
                 remove(removeEvent.index());
                 break;
-            case INIT:
-            case REORDER:
-                reset();
-                break;
             case MOVE:
                 final MoveEvent moveEvent = (MoveEvent) event;
                 move(moveEvent.getFromIndex(), moveEvent.getToIndex());
@@ -195,6 +194,7 @@ public class MediaSourceManager implements DeferredMediaSource.Callback {
     private boolean tryBlock() {
         if (!isBlocked) {
             playbackListener.block();
+            resetSources();
             isBlocked = true;
             return true;
         }
@@ -202,7 +202,7 @@ public class MediaSourceManager implements DeferredMediaSource.Callback {
     }
 
     private boolean tryUnblock() {
-        if (isPlayQueueReady() && isBlocked) {
+        if (isPlayQueueReady() && isBlocked && sources != null) {
             isBlocked = false;
             playbackListener.unblock(sources);
             return true;
@@ -216,7 +216,7 @@ public class MediaSourceManager implements DeferredMediaSource.Callback {
         final Consumer<StreamInfo> syncPlayback = new Consumer<StreamInfo>() {
             @Override
             public void accept(StreamInfo streamInfo) throws Exception {
-                playbackListener.sync(streamInfo);
+                playbackListener.sync(currentItem, streamInfo);
             }
         };
 
@@ -224,7 +224,7 @@ public class MediaSourceManager implements DeferredMediaSource.Callback {
             @Override
             public void accept(Throwable throwable) throws Exception {
                 Log.e(TAG, "Sync error:", throwable);
-                playbackListener.sync(null);
+                playbackListener.sync(currentItem,null);
             }
         };
 
@@ -244,11 +244,12 @@ public class MediaSourceManager implements DeferredMediaSource.Callback {
 
     private void resetSources() {
         if (this.sources != null) this.sources.releaseSource();
-
         this.sources = new DynamicConcatenatingMediaSource();
     }
 
     private void populateSources() {
+        if (sources == null) return;
+
         for (final PlayQueueItem item : playQueue.getStreams()) {
             insert(playQueue.indexOf(item), new DeferredMediaSource(item, this));
         }

app/src/main/java/org/schabi/newpipe/player/playback/PlaybackListener.java

@@ -1,41 +1,43 @@
 package org.schabi.newpipe.player.playback;
 
+import android.support.annotation.NonNull;
 import android.support.annotation.Nullable;
 
 import com.google.android.exoplayer2.source.MediaSource;
 
 import org.schabi.newpipe.extractor.stream.StreamInfo;
+import org.schabi.newpipe.playlist.PlayQueueItem;
 
 import java.util.List;
 
 public interface PlaybackListener {
-    /*
+    /**
      * Called when the stream at the current queue index is not ready yet.
-    * Signals to the listener to block the player from playing anything.
+     * Signals to the listener to block the player from playing anything and notify the source
+     * is now invalid.
      *
      * May be called at any time.
      * */
     void block();
 
-    /*
+    /**
      * Called when the stream at the current queue index is ready.
-    * Signals to the listener to resume the player.
+     * Signals to the listener to resume the player by preparing a new source.
      *
      * May be called only when the player is blocked.
      * */
     void unblock(final MediaSource mediaSource);
 
-    /*
+    /**
      * Called when the queue index is refreshed.
      * Signals to the listener to synchronize the player's window to the manager's
      * window.
      *
-    * May be null.
+     * May be called only after unblock is called.
-    * May be called only after playback is unblocked.
      * */
-    void sync(@Nullable final StreamInfo info);
+    void sync(@NonNull final PlayQueueItem item, @Nullable final StreamInfo info);
 
-    /*
+    /**
      * Requests the listener to resolve a stream info into a media source
      * according to the listener's implementation (background, popup or main video player).
      *
@@ -43,7 +45,7 @@ public interface PlaybackListener {
      * */
     MediaSource sourceOf(final StreamInfo info);
 
-    /*
+    /**
      * Called when the play queue can no longer to played or used.
      * Currently, this means the play queue is empty and complete.
      * Signals to the listener that it should shutdown.