From 9e238eb6d365e76b20e39147aeae5091ea4451ee Mon Sep 17 00:00:00 2001
From: bachinger <bachinger@google.com>
Date: Tue, 3 Dec 2019 16:05:27 +0000
Subject: [PATCH] MediaSessionConnector: Support ACTION_SET_CAPTIONING_ENABLED

PiperOrigin-RevId: 283546707
---
 RELEASENOTES.md                               |  2 +
 .../mediasession/MediaSessionConnector.java   | 54 +++++++++++++++++--
 2 files changed, 53 insertions(+), 3 deletions(-)

diff --git a/RELEASENOTES.md b/RELEASENOTES.md
index d0ae1a3b5a..1911d32cdd 100644
--- a/RELEASENOTES.md
+++ b/RELEASENOTES.md
@@ -131,6 +131,8 @@
     of the extension after this change, following the instructions in the
     extension's readme.
 * Opus extension: Update to use NDK r20.
+* MediaSession extension: Make media session connector dispatch
+  `ACTION_SET_CAPTIONING_ENABLED`.
 * GVR extension: This extension is now deprecated.
 * Demo apps (TODO: update links to point to r2.11.0 tag):
   * Add [SurfaceControl demo app](https://github.com/google/ExoPlayer/tree/dev-v2/demos/surface)
diff --git a/extensions/mediasession/src/main/java/com/google/android/exoplayer2/ext/mediasession/MediaSessionConnector.java b/extensions/mediasession/src/main/java/com/google/android/exoplayer2/ext/mediasession/MediaSessionConnector.java
index 84d5fea0c7..5382e286a1 100644
--- a/extensions/mediasession/src/main/java/com/google/android/exoplayer2/ext/mediasession/MediaSessionConnector.java
+++ b/extensions/mediasession/src/main/java/com/google/android/exoplayer2/ext/mediasession/MediaSessionConnector.java
@@ -339,6 +339,21 @@ public final class MediaSessionConnector {
     void onSetRating(Player player, RatingCompat rating, Bundle extras);
   }
 
+  /** Handles requests for enabling or disabling captions. */
+  public interface CaptionCallback extends CommandReceiver {
+
+    /** See {@link MediaSessionCompat.Callback#onSetCaptioningEnabled(boolean)}. */
+    void onSetCaptioningEnabled(Player player, boolean enabled);
+
+    /**
+     * Returns whether the media currently being played has captions.
+     *
+     * <p>This method is called each time the media session playback state needs to be updated and
+     * published upon a player state change.
+     */
+    boolean hasCaptions(Player player);
+  }
+
   /** Handles a media button event. */
   public interface MediaButtonEventHandler {
     /**
@@ -420,6 +435,7 @@ public final class MediaSessionConnector {
   @Nullable private QueueNavigator queueNavigator;
   @Nullable private QueueEditor queueEditor;
   @Nullable private RatingCallback ratingCallback;
+  @Nullable private CaptionCallback captionCallback;
   @Nullable private MediaButtonEventHandler mediaButtonEventHandler;
 
   private long enabledPlaybackActions;
@@ -606,7 +622,7 @@ public final class MediaSessionConnector {
    *
    * @param ratingCallback The rating callback.
    */
-  public void setRatingCallback(RatingCallback ratingCallback) {
+  public void setRatingCallback(@Nullable RatingCallback ratingCallback) {
     if (this.ratingCallback != ratingCallback) {
       unregisterCommandReceiver(this.ratingCallback);
       this.ratingCallback = ratingCallback;
@@ -614,6 +630,19 @@ public final class MediaSessionConnector {
     }
   }
 
+  /**
+   * Sets the {@link CaptionCallback} to handle requests to enable or disable captions.
+   *
+   * @param captionCallback The caption callback.
+   */
+  public void setCaptionCallback(@Nullable CaptionCallback captionCallback) {
+    if (this.captionCallback != captionCallback) {
+      unregisterCommandReceiver(this.captionCallback);
+      this.captionCallback = captionCallback;
+      registerCommandReceiver(this.captionCallback);
+    }
+  }
+
   /**
    * Sets a custom error on the session.
    *
@@ -843,12 +872,14 @@ public final class MediaSessionConnector {
     boolean enableRewind = false;
     boolean enableFastForward = false;
     boolean enableSetRating = false;
+    boolean enableSetCaptioningEnabled = false;
     Timeline timeline = player.getCurrentTimeline();
     if (!timeline.isEmpty() && !player.isPlayingAd()) {
       enableSeeking = player.isCurrentWindowSeekable();
       enableRewind = enableSeeking && rewindMs > 0;
       enableFastForward = enableSeeking && fastForwardMs > 0;
-      enableSetRating = true;
+      enableSetRating = ratingCallback != null;
+      enableSetCaptioningEnabled = captionCallback != null && captionCallback.hasCaptions(player);
     }
 
     long playbackActions = BASE_PLAYBACK_ACTIONS;
@@ -868,9 +899,12 @@ public final class MediaSessionConnector {
       actions |=
           (QueueNavigator.ACTIONS & queueNavigator.getSupportedQueueNavigatorActions(player));
     }
-    if (ratingCallback != null && enableSetRating) {
+    if (enableSetRating) {
       actions |= PlaybackStateCompat.ACTION_SET_RATING;
     }
+    if (enableSetCaptioningEnabled) {
+      actions |= PlaybackStateCompat.ACTION_SET_CAPTIONING_ENABLED;
+    }
     return actions;
   }
 
@@ -901,6 +935,13 @@ public final class MediaSessionConnector {
     return player != null && ratingCallback != null;
   }
 
+  @EnsuresNonNullIf(
+      result = true,
+      expression = {"player", "captionCallback"})
+  private boolean canDispatchSetCaptioningEnabled() {
+    return player != null && captionCallback != null;
+  }
+
   @EnsuresNonNullIf(
       result = true,
       expression = {"player", "queueEditor"})
@@ -1353,6 +1394,13 @@ public final class MediaSessionConnector {
       }
     }
 
+    @Override
+    public void onSetCaptioningEnabled(boolean enabled) {
+      if (canDispatchSetCaptioningEnabled()) {
+        captionCallback.onSetCaptioningEnabled(player, enabled);
+      }
+    }
+
     @Override
     public boolean onMediaButtonEvent(Intent mediaButtonEvent) {
       boolean isHandled =