content: /*
   * Copyright (C) 2016 The Android Open Source Project
   *
   * Licensed under the Apache License, Version 2.0 (the "License");
   * you may not use this file except in compliance with the License.
   * You may obtain a copy of the License at
   *
   *      http://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS,
   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   * See the License for the specific language governing permissions and
   * limitations under the License.
   */
  package com.google.android.exoplayer2.video;
  
  import static com.google.android.exoplayer2.util.Util.castNonNull;
  
  import android.media.MediaCodec;
  import android.media.MediaCodec.CodecException;
  import android.os.Handler;
  import android.os.SystemClock;
  import android.view.Surface;
  import androidx.annotation.Nullable;
  import com.google.android.exoplayer2.Format;
  import com.google.android.exoplayer2.Player;
  import com.google.android.exoplayer2.Renderer;
  import com.google.android.exoplayer2.decoder.DecoderCounters;
  import com.google.android.exoplayer2.decoder.DecoderException;
  import com.google.android.exoplayer2.decoder.DecoderReuseEvaluation;
  import com.google.android.exoplayer2.util.Assertions;
  
  /**
   * Listener of video {@link Renderer} events. All methods have no-op default implementations to
   * allow selective overrides.
   */
  public interface VideoRendererEventListener {
  
    /**
     * Called when the renderer is enabled.
     *
     * @param counters {@link DecoderCounters} that will be updated by the renderer for as long as it
     *     remains enabled.
     */
    default void onVideoEnabled(DecoderCounters counters) {}
  
    /**
     * Called when a decoder is created.
     *
     * @param decoderName The decoder that was created.
     * @param initializedTimestampMs {@link SystemClock#elapsedRealtime()} when initialization
     *     finished.
     * @param initializationDurationMs The time taken to initialize the decoder in milliseconds.
     */
    default void onVideoDecoderInitialized(
        String decoderName, long initializedTimestampMs, long initializationDurationMs) {}
  
    /**
     * @deprecated Use {@link #onVideoInputFormatChanged(Format, DecoderReuseEvaluation)}.
     */
    @Deprecated
    default void onVideoInputFormatChanged(Format format) {}
  
    /**
     * Called when the format of the media being consumed by the renderer changes.
     *
     * @param format The new format.
     * @param decoderReuseEvaluation The result of the evaluation to determine whether an existing
     *     decoder instance can be reused for the new format, or {@code null} if the renderer did not
     *     have a decoder.
     */
    default void onVideoInputFormatChanged(
        Format format, @Nullable DecoderReuseEvaluation decoderReuseEvaluation) {}
  
    /**
     * Called to report the number of frames dropped by the renderer. Dropped frames are reported
     * whenever the renderer is stopped having dropped frames, and optionally, whenever the count
     * reaches a specified threshold whilst the renderer is started.
     *
     * @param count The number of dropped frames.
     * @param elapsedMs The duration in milliseconds over which the frames were dropped. This duration
     *     is timed from when the renderer was started or from when dropped frames were last reported
     *     (whichever was more recent), and not from when the first of the reported drops occurred.
     */
    default void onDroppedFrames(int count, long elapsedMs) {}
  
    /**
     * Called to report the video processing offset of video frames processed by the video renderer.
     *
     * <p>Video processing offset represents how early a video frame is processed compared to the
     * player's current position. For each video frame, the offset is calculated as <em>P<sub>vf</sub>
     * - P<sub>pl</sub></em> where <em>P<sub>vf</sub></em> is the presentation timestamp of the video
     * frame and <em>P<sub>pl</sub></em> is the current position of the player. Positive values
     * indicate the frame was processed early enough whereas negative values indicate that the
     * player's position had progressed beyond the frame's timestamp when the frame was processed (and
     * the frame was probably dropped).
     *
     * <p>The renderer reports the sum of video processing offset samples (one sample per processed
     * video frame: dropped, skipped or rendered) and the total number of samples.
     *
     * @param totalProcessingOffsetUs The sum of all video frame processing offset samples for the
     *     video frames processed by the renderer in microseconds.
     * @param frameCount The number of samples included in the {@code totalProcessingOffsetUs}.
     */
    default void onVideoFrameProcessingOffset(long totalProcessingOffsetUs, int frameCount) {}
  
    /**
     * Called before a frame is rendered for the first time since setting the surface, and each time
     * there's a change in the size, rotation or pixel aspect ratio of the video being rendered.
     *
     * @param videoSize The new size of the video.
     */
    default void onVideoSizeChanged(VideoSize videoSize) {}
  
    /**
     * Called when a frame is rendered for the first time since setting the output, or since the
     * renderer was reset, or since the stream being rendered was changed.
     *
     * @param output The output of the video renderer. Normally a {@link Surface}, however some video
     *     renderers may have other output types (e.g., a {@link VideoDecoderOutputBufferRenderer}).
     * @param renderTimeMs The {@link SystemClock#elapsedRealtime()} when the frame was rendered.
     */
    default void onRenderedFirstFrame(Object output, long renderTimeMs) {}
  
    /**
     * Called when a decoder is released.
     *
     * @param decoderName The decoder that was released.
     */
    default void onVideoDecoderReleased(String decoderName) {}
  
    /**
     * Called when the renderer is disabled.
     *
     * @param counters {@link DecoderCounters} that were updated by the renderer.
     */
    default void onVideoDisabled(DecoderCounters counters) {}
  
    /**
     * Called when a video decoder encounters an error.
     *
     * <p>This method being called does not indicate that playback has failed, or that it will fail.
     * The player may be able to recover from the error. Hence applications should <em>not</em>
     * implement this method to display a user visible error or initiate an application level retry.
     * {@link Player.Listener#onPlayerError} is the appropriate place to implement such behavior. This
     * method is called to provide the application with an opportunity to log the error if it wishes
     * to do so.
     *
     * @param videoCodecError The error. Typically a {@link CodecException} if the renderer uses
     *     {@link MediaCodec}, or a {@link DecoderException} if the renderer uses a software decoder.
     */
    default void onVideoCodecError(Exception videoCodecError) {}
  
    /** Dispatches events to a {@link VideoRendererEventListener}. */
    final class EventDispatcher {
  
      @Nullable private final Handler handler;
      @Nullable private final VideoRendererEventListener listener;
  
      /**
       * @param handler A handler for dispatching events, or null if events should not be dispatched.
       * @param listener The listener to which events should be dispatched, or null if events should
       *     not be dispatched.
       */
      public EventDispatcher(
          @Nullable Handler handler, @Nullable VideoRendererEventListener listener) {
        this.handler = listener != null ? Assertions.checkNotNull(handler) : null;
        this.listener = listener;
      }
  
      /** Invokes {@link VideoRendererEventListener#onVideoEnabled(DecoderCounters)}. */
      public void enabled(DecoderCounters decoderCounters) {
        if (handler != null) {
          handler.post(() -> castNonNull(listener).onVideoEnabled(decoderCounters));
        }
      }
  
      /** Invokes {@link VideoRendererEventListener#onVideoDecoderInitialized(String, long, long)}. */
      public void decoderInitialized(
          String decoderName, long initializedTimestampMs, long initializationDurationMs) {
        if (handler != null) {
          handler.post(
              () ->
                  castNonNull(listener)
                      .onVideoDecoderInitialized(
                          decoderName, initializedTimestampMs, initializationDurationMs));
        }
      }
  
      /**
       * Invokes {@link VideoRendererEventListener#onVideoInputFormatChanged(Format,
       * DecoderReuseEvaluation)}.
       */
      @SuppressWarnings("deprecation") // Calling deprecated listener method.
      public void inputFormatChanged(
          Format format, @Nullable DecoderReuseEvaluation decoderReuseEvaluation) {
        if (handler != null) {
          handler.post(
              () -> {
                castNonNull(listener).onVideoInputFormatChanged(format);
                castNonNull(listener).onVideoInputFormatChanged(format, decoderReuseEvaluation);
              });
        }
      }
  
      /** Invokes {@link VideoRendererEventListener#onDroppedFrames(int, long)}. */
      public void droppedFrames(int droppedFrameCount, long elapsedMs) {
        if (handler != null) {
          handler.post(() -> castNonNull(listener).onDroppedFrames(droppedFrameCount, elapsedMs));
        }
      }
  
      /** Invokes {@link VideoRendererEventListener#onVideoFrameProcessingOffset}. */
      public void reportVideoFrameProcessingOffset(long totalProcessingOffsetUs, int frameCount) {
        if (handler != null) {
          handler.post(
              () ->
                  castNonNull(listener)
                      .onVideoFrameProcessingOffset(totalProcessingOffsetUs, frameCount));
        }
      }
  
      /** Invokes {@link VideoRendererEventListener#onVideoSizeChanged(VideoSize)}. */
      public void videoSizeChanged(VideoSize videoSize) {
        if (handler != null) {
          handler.post(() -> castNonNull(listener).onVideoSizeChanged(videoSize));
        }
      }
  
      /** Invokes {@link VideoRendererEventListener#onRenderedFirstFrame(Object, long)}. */
      public void renderedFirstFrame(Object output) {
        if (handler != null) {
          // TODO: Replace this timestamp with the actual frame release time.
          long renderTimeMs = SystemClock.elapsedRealtime();
          handler.post(() -> castNonNull(listener).onRenderedFirstFrame(output, renderTimeMs));
        }
      }
  
      /** Invokes {@link VideoRendererEventListener#onVideoDecoderReleased(String)}. */
      public void decoderReleased(String decoderName) {
        if (handler != null) {
          handler.post(() -> castNonNull(listener).onVideoDecoderReleased(decoderName));
        }
      }
  
      /** Invokes {@link VideoRendererEventListener#onVideoDisabled(DecoderCounters)}. */
      public void disabled(DecoderCounters counters) {
        counters.ensureUpdated();
        if (handler != null) {
          handler.post(
              () -> {
                counters.ensureUpdated();
                castNonNull(listener).onVideoDisabled(counters);
              });
        }
      }
  
      /** Invokes {@link VideoRendererEventListener#onVideoCodecError(Exception)}. */
      public void videoCodecError(Exception videoCodecError) {
        if (handler != null) {
          handler.post(() -> castNonNull(listener).onVideoCodecError(videoCodecError));
        }
      }
    }
  }
  