Merge pull request #2226 from nift4:shuffle

PiperOrigin-RevId: 770065234

Author: copybara-github

RELEASENOTES.md

@@ -13,6 +13,8 @@
     *   Throw `IllegalStateException` when `PreloadMediaSource` is played by an
         `ExoPlayer` with a playback thread that is different than the preload
         thread ([#2495](https://github.com/androidx/media/issues/2495)).
+    *   Add `cloneAndMove` to `ShuffleMode` with a default implementation
+        ([#2226](https://github.com/androidx/media/pull/2226)).
 *   Transformer:
     *   Add `CodecDbLite` that enables chipset specific optimizations of video
         encoding settings.

libraries/exoplayer/src/main/java/androidx/media3/exoplayer/ExoPlayerImpl.java

@@ -704,6 +704,7 @@ public void moveMediaItems(int fromIndex, int toIndex, int newFromIndex) {
     Timeline oldTimeline = getCurrentTimeline();
     pendingOperationAcks++;
     Util.moveItems(mediaSourceHolderSnapshots, fromIndex, toIndex, newFromIndex);
+    shuffleOrder = shuffleOrder.cloneAndMove(fromIndex, toIndex, newFromIndex);
     Timeline newTimeline = createMaskingTimeline();
     PlaybackInfo newPlaybackInfo =
         maskTimelineAndPosition(

libraries/exoplayer/src/main/java/androidx/media3/exoplayer/source/ShuffleOrder.java

@@ -266,6 +266,24 @@ public ShuffleOrder cloneAndClear() {
    */
   ShuffleOrder cloneAndInsert(int insertionIndex, int insertionCount);
 
+  /**
+   * Returns a copy of the shuffle order to be used after a move.
+   *
+   * <p>The default implementation is a no-op. Custom implementation can choose to re-shuffle when
+   * items are moved.
+   *
+   * @param indexFrom The starting index in the unshuffled order of the range to move, from before
+   *     the move occurs.
+   * @param indexToExclusive The smallest index (must be greater or equal to {@code indexFrom}) that
+   *     is not included in the range of elements moved, from before the move occurs.
+   * @param newIndexFrom The starting index in the unshuffled order of the range to move, from after
+   *     the move occurs.
+   * @return A copy of this {@link ShuffleOrder} with the elements moved.
+   */
+  default ShuffleOrder cloneAndMove(int indexFrom, int indexToExclusive, int newIndexFrom) {
+    return this;
+  }
+
   /**
    * Returns a copy of the shuffle order with a range of elements removed.
    *