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;
  
  import static com.google.android.exoplayer2.util.Assertions.checkNotNull;
  import static java.lang.Math.max;
  
  import androidx.annotation.Nullable;
  import com.google.android.exoplayer2.analytics.PlayerId;
  import com.google.android.exoplayer2.decoder.DecoderInputBuffer;
  import com.google.android.exoplayer2.decoder.DecoderInputBuffer.InsufficientCapacityException;
  import com.google.android.exoplayer2.source.SampleStream;
  import com.google.android.exoplayer2.source.SampleStream.ReadDataResult;
  import com.google.android.exoplayer2.source.SampleStream.ReadFlags;
  import com.google.android.exoplayer2.util.Assertions;
  import com.google.android.exoplayer2.util.MediaClock;
  import java.io.IOException;
  import org.checkerframework.checker.nullness.qual.MonotonicNonNull;
  
  /** An abstract base class suitable for most {@link Renderer} implementations. */
  public abstract class BaseRenderer implements Renderer, RendererCapabilities {
  
    private final @C.TrackType int trackType;
    private final FormatHolder formatHolder;
  
    @Nullable private RendererConfiguration configuration;
    private int index;
    private @MonotonicNonNull PlayerId playerId;
    private int state;
    @Nullable private SampleStream stream;
    @Nullable private Format[] streamFormats;
    private long streamOffsetUs;
    private long lastResetPositionUs;
    private long readingPositionUs;
    private boolean streamIsFinal;
    private boolean throwRendererExceptionIsExecuting;
  
    /**
     * @param trackType The track type that the renderer handles. One of the {@link C} {@code
     *     TRACK_TYPE_*} constants.
     */
    public BaseRenderer(@C.TrackType int trackType) {
      this.trackType = trackType;
      formatHolder = new FormatHolder();
      readingPositionUs = C.TIME_END_OF_SOURCE;
    }
  
    @Override
    public final @C.TrackType int getTrackType() {
      return trackType;
    }
  
    @Override
    public final RendererCapabilities getCapabilities() {
      return this;
    }
  
    @Override
    public final void init(int index, PlayerId playerId) {
      this.index = index;
      this.playerId = playerId;
    }
  
    @Override
    @Nullable
    public MediaClock getMediaClock() {
      return null;
    }
  
    @Override
    public final int getState() {
      return state;
    }
  
    @Override
    public final void enable(
        RendererConfiguration configuration,
        Format[] formats,
        SampleStream stream,
        long positionUs,
        boolean joining,
        boolean mayRenderStartOfStream,
        long startPositionUs,
        long offsetUs)
        throws ExoPlaybackException {
      Assertions.checkState(state == STATE_DISABLED);
      this.configuration = configuration;
      state = STATE_ENABLED;
      onEnabled(joining, mayRenderStartOfStream);
      replaceStream(formats, stream, startPositionUs, offsetUs);
      resetPosition(positionUs, joining);
    }
  
    @Override
    public final void start() throws ExoPlaybackException {
      Assertions.checkState(state == STATE_ENABLED);
      state = STATE_STARTED;
      onStarted();
    }
  
    @Override
    public final void replaceStream(
        Format[] formats, SampleStream stream, long startPositionUs, long offsetUs)
        throws ExoPlaybackException {
      Assertions.checkState(!streamIsFinal);
      this.stream = stream;
      if (readingPositionUs == C.TIME_END_OF_SOURCE) {
        readingPositionUs = startPositionUs;
      }
      streamFormats = formats;
      streamOffsetUs = offsetUs;
      onStreamChanged(formats, startPositionUs, offsetUs);
    }
  
    @Override
    @Nullable
    public final SampleStream getStream() {
      return stream;
    }
  
    @Override
    public final boolean hasReadStreamToEnd() {
      return readingPositionUs == C.TIME_END_OF_SOURCE;
    }
  
    @Override
    public final long getReadingPositionUs() {
      return readingPositionUs;
    }
  
    @Override
    public final void setCurrentStreamFinal() {
      streamIsFinal = true;
    }
  
    @Override
    public final boolean isCurrentStreamFinal() {
      return streamIsFinal;
    }
  
    @Override
    public final void maybeThrowStreamError() throws IOException {
      Assertions.checkNotNull(stream).maybeThrowError();
    }
  
    @Override
    public final void resetPosition(long positionUs) throws ExoPlaybackException {
      resetPosition(positionUs, /* joining= */ false);
    }
  
    private void resetPosition(long positionUs, boolean joining) throws ExoPlaybackException {
      streamIsFinal = false;
      lastResetPositionUs = positionUs;
      readingPositionUs = positionUs;
      onPositionReset(positionUs, joining);
    }
  
    @Override
    public final void stop() {
      Assertions.checkState(state == STATE_STARTED);
      state = STATE_ENABLED;
      onStopped();
    }
  
    @Override
    public final void disable() {
      Assertions.checkState(state == STATE_ENABLED);
      formatHolder.clear();
      state = STATE_DISABLED;
      stream = null;
      streamFormats = null;
      streamIsFinal = false;
      onDisabled();
    }
  
    @Override
    public final void reset() {
      Assertions.checkState(state == STATE_DISABLED);
      formatHolder.clear();
      onReset();
    }
  
    // RendererCapabilities implementation.
  
    @Override
    public @AdaptiveSupport int supportsMixedMimeTypeAdaptation() throws ExoPlaybackException {
      return ADAPTIVE_NOT_SUPPORTED;
    }
  
    // PlayerMessage.Target implementation.
  
    @Override
    public void handleMessage(@MessageType int messageType, @Nullable Object message)
        throws ExoPlaybackException {
      // Do nothing.
    }
  
    // Methods to be overridden by subclasses.
  
    /**
     * Called when the renderer is enabled.
     *
     * <p>The default implementation is a no-op.
     *
     * @param joining Whether this renderer is being enabled to join an ongoing playback.
     * @param mayRenderStartOfStream Whether this renderer is allowed to render the start of the
     *     stream even if the state is not {@link #STATE_STARTED} yet.
     * @throws ExoPlaybackException If an error occurs.
     */
    protected void onEnabled(boolean joining, boolean mayRenderStartOfStream)
        throws ExoPlaybackException {
      // Do nothing.
    }
  
    /**
     * Called when the renderer's stream has changed. This occurs when the renderer is enabled after
     * {@link #onEnabled(boolean, boolean)} has been called, and also when the stream has been
     * replaced whilst the renderer is enabled or started.
     *
     * <p>The default implementation is a no-op.
     *
     * @param formats The enabled formats.
     * @param startPositionUs The start position of the new stream in renderer time (microseconds).
     * @param offsetUs The offset that will be added to the timestamps of buffers read via {@link
     *     #readSource} so that decoder input buffers have monotonically increasing timestamps.
     * @throws ExoPlaybackException If an error occurs.
     */
    protected void onStreamChanged(Format[] formats, long startPositionUs, long offsetUs)
        throws ExoPlaybackException {
      // Do nothing.
    }
  
    /**
     * Called when the position is reset. This occurs when the renderer is enabled after {@link
     * #onStreamChanged(Format[], long, long)} has been called, and also when a position discontinuity
     * is encountered.
     *
     * <p>After a position reset, the renderer's {@link SampleStream} is guaranteed to provide samples
     * starting from a key frame.
     *
     * <p>The default implementation is a no-op.
     *
     * @param positionUs The new playback position in microseconds.
     * @param joining Whether this renderer is being enabled to join an ongoing playback.
     * @throws ExoPlaybackException If an error occurs.
     */
    protected void onPositionReset(long positionUs, boolean joining) throws ExoPlaybackException {
      // Do nothing.
    }
  
    /**
     * Called when the renderer is started.
     *
     * <p>The default implementation is a no-op.
     *
     * @throws ExoPlaybackException If an error occurs.
     */
    protected void onStarted() throws ExoPlaybackException {
      // Do nothing.
    }
  
    /**
     * Called when the renderer is stopped.
     *
     * <p>The default implementation is a no-op.
     */
    protected void onStopped() {
      // Do nothing.
    }
  
    /**
     * Called when the renderer is disabled.
     *
     * <p>The default implementation is a no-op.
     */
    protected void onDisabled() {
      // Do nothing.
    }
  
    /**
     * Called when the renderer is reset.
     *
     * <p>The default implementation is a no-op.
     */
    protected void onReset() {
      // Do nothing.
    }
  
    // Methods to be called by subclasses.
  
    /**
     * Returns the position passed to the most recent call to {@link #enable} or {@link
     * #resetPosition}.
     */
    protected final long getLastResetPositionUs() {
      return lastResetPositionUs;
    }
  
    /** Returns a clear {@link FormatHolder}. */
    protected final FormatHolder getFormatHolder() {
      formatHolder.clear();
      return formatHolder;
    }
  
    /**
     * Returns the formats of the currently enabled stream.
     *
     * <p>This method may be called when the renderer is in the following states: {@link
     * #STATE_ENABLED}, {@link #STATE_STARTED}.
     */
    protected final Format[] getStreamFormats() {
      return Assertions.checkNotNull(streamFormats);
    }
  
    /**
     * Returns the configuration set when the renderer was most recently enabled.
     *
     * <p>This method may be called when the renderer is in the following states: {@link
     * #STATE_ENABLED}, {@link #STATE_STARTED}.
     */
    protected final RendererConfiguration getConfiguration() {
      return Assertions.checkNotNull(configuration);
    }
  
    /**
     * Returns the index of the renderer within the player.
     *
     * <p>Must only be used after the renderer has been initialized by the player.
     */
    protected final int getIndex() {
      return index;
    }
  
    /**
     * Returns the {@link PlayerId} of the player using this renderer.
     *
     * <p>Must only be used after the renderer has been initialized by the player.
     */
    protected final PlayerId getPlayerId() {
      return checkNotNull(playerId);
    }
  
    /**
     * Creates an {@link ExoPlaybackException} of type {@link ExoPlaybackException#TYPE_RENDERER} for
     * this renderer.
     *
     * @param cause The cause of the exception.
     * @param format The current format used by the renderer. May be null.
     * @param errorCode A {@link PlaybackException.ErrorCode} to identify the cause of the playback
     *     failure.
     * @return The created instance, in which {@link ExoPlaybackException#isRecoverable} is {@code
     *     false}.
     */
    protected final ExoPlaybackException createRendererException(
        Throwable cause, @Nullable Format format, @PlaybackException.ErrorCode int errorCode) {
      return createRendererException(cause, format, /* isRecoverable= */ false, errorCode);
    }
  
    /**
     * Creates an {@link ExoPlaybackException} of type {@link ExoPlaybackException#TYPE_RENDERER} for
     * this renderer.
     *
     * @param cause The cause of the exception.
     * @param format The current format used by the renderer. May be null.
     * @param isRecoverable If the error is recoverable by disabling and re-enabling the renderer.
     * @param errorCode A {@link PlaybackException.ErrorCode} to identify the cause of the playback
     *     failure.
     * @return The created instance.
     */
    protected final ExoPlaybackException createRendererException(
        Throwable cause,
        @Nullable Format format,
        boolean isRecoverable,
        @PlaybackException.ErrorCode int errorCode) {
      @C.FormatSupport int formatSupport = C.FORMAT_HANDLED;
      if (format != null && !throwRendererExceptionIsExecuting) {
        // Prevent recursive re-entry from subclass supportsFormat implementations.
        throwRendererExceptionIsExecuting = true;
        try {
          formatSupport = RendererCapabilities.getFormatSupport(supportsFormat(format));
        } catch (ExoPlaybackException e) {
          // Ignore, we are already failing.
        } finally {
          throwRendererExceptionIsExecuting = false;
        }
      }
      return ExoPlaybackException.createForRenderer(
          cause, getName(), getIndex(), format, formatSupport, isRecoverable, errorCode);
    }
  
    /**
     * Reads from the enabled upstream source. If the upstream source has been read to the end then
     * {@link C#RESULT_BUFFER_READ} is only returned if {@link #setCurrentStreamFinal()} has been
     * called. {@link C#RESULT_NOTHING_READ} is returned otherwise.
     *
     * <p>This method may be called when the renderer is in the following states: {@link
     * #STATE_ENABLED}, {@link #STATE_STARTED}.
     *
     * @param formatHolder A {@link FormatHolder} to populate in the case of reading a format.
     * @param buffer A {@link DecoderInputBuffer} to populate in the case of reading a sample or the
     *     end of the stream. If the end of the stream has been reached, the {@link
     *     C#BUFFER_FLAG_END_OF_STREAM} flag will be set on the buffer.
     * @param readFlags Flags controlling the behavior of this read operation.
     * @return The {@link ReadDataResult result} of the read operation.
     * @throws InsufficientCapacityException If the {@code buffer} has insufficient capacity to hold
     *     the data of a sample being read. The buffer {@link DecoderInputBuffer#timeUs timestamp} and
     *     flags are populated if this exception is thrown, but the read position is not advanced.
     */
    protected final @ReadDataResult int readSource(
        FormatHolder formatHolder, DecoderInputBuffer buffer, @ReadFlags int readFlags) {
      @ReadDataResult
      int result = Assertions.checkNotNull(stream).readData(formatHolder, buffer, readFlags);
      if (result == C.RESULT_BUFFER_READ) {
        if (buffer.isEndOfStream()) {
          readingPositionUs = C.TIME_END_OF_SOURCE;
          return streamIsFinal ? C.RESULT_BUFFER_READ : C.RESULT_NOTHING_READ;
        }
        buffer.timeUs += streamOffsetUs;
        readingPositionUs = max(readingPositionUs, buffer.timeUs);
      } else if (result == C.RESULT_FORMAT_READ) {
        Format format = Assertions.checkNotNull(formatHolder.format);
        if (format.subsampleOffsetUs != Format.OFFSET_SAMPLE_RELATIVE) {
          format =
              format
                  .buildUpon()
                  .setSubsampleOffsetUs(format.subsampleOffsetUs + streamOffsetUs)
                  .build();
          formatHolder.format = format;
        }
      }
      return result;
    }
  
    /**
     * Attempts to skip to the keyframe before the specified position, or to the end of the stream if
     * {@code positionUs} is beyond it.
     *
     * <p>This method may be called when the renderer is in the following states: {@link
     * #STATE_ENABLED}, {@link #STATE_STARTED}.
     *
     * @param positionUs The position in microseconds.
     * @return The number of samples that were skipped.
     */
    protected int skipSource(long positionUs) {
      return Assertions.checkNotNull(stream).skipData(positionUs - streamOffsetUs);
    }
  
    /**
     * Returns whether the upstream source is ready.
     *
     * <p>This method may be called when the renderer is in the following states: {@link
     * #STATE_ENABLED}, {@link #STATE_STARTED}.
     */
    protected final boolean isSourceReady() {
      return hasReadStreamToEnd() ? streamIsFinal : Assertions.checkNotNull(stream).isReady();
    }
  }
  