content: /*
   * Copyright (C) 2022 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.audio;
  
  import static com.google.android.exoplayer2.C.MICROS_PER_SECOND;
  import static com.google.android.exoplayer2.audio.DefaultAudioSink.OUTPUT_MODE_PASSTHROUGH;
  import static com.google.android.exoplayer2.audio.DefaultAudioTrackBufferSizeProvider.getMaximumEncodedRateBytesPerSecond;
  import static com.google.common.truth.Truth.assertThat;
  
  import androidx.test.ext.junit.runners.AndroidJUnit4;
  import com.google.android.exoplayer2.C;
  import com.google.android.exoplayer2.Format;
  import org.junit.Test;
  import org.junit.runner.RunWith;
  
  /** Tests for {@link DefaultAudioTrackBufferSizeProvider} AC3 audio. */
  @RunWith(AndroidJUnit4.class)
  public class DefaultAudioTrackBufferSizeProviderAC3Test {
  
    private static final DefaultAudioTrackBufferSizeProvider DEFAULT =
        new DefaultAudioTrackBufferSizeProvider.Builder().build();
  
    @Test
    public void
        getBufferSizeInBytes_passthroughAc3AndNoBitrate_assumesMaxByteRateTimesMultiplicationFactor() {
      int bufferSize =
          DEFAULT.getBufferSizeInBytes(
              /* minBufferSizeInBytes= */ 0,
              /* encoding= */ C.ENCODING_AC3,
              /* outputMode= */ OUTPUT_MODE_PASSTHROUGH,
              /* pcmFrameSize= */ 1,
              /* sampleRate= */ 0,
              /* bitrate= */ Format.NO_VALUE,
              /* maxAudioTrackPlaybackSpeed= */ 1);
  
      assertThat(bufferSize)
          .isEqualTo(
              durationUsToAc3MaxBytes(DEFAULT.passthroughBufferDurationUs)
                  * DEFAULT.ac3BufferMultiplicationFactor);
    }
  
    @Test
    public void
        getBufferSizeInBytes_passthroughAC3At256Kbits_isPassthroughBufferSizeTimesMultiplicationFactor() {
      int bufferSize =
          DEFAULT.getBufferSizeInBytes(
              /* minBufferSizeInBytes= */ 0,
              /* encoding= */ C.ENCODING_AC3,
              /* outputMode= */ OUTPUT_MODE_PASSTHROUGH,
              /* pcmFrameSize= */ 1,
              /* sampleRate= */ 0,
              /* bitrate= */ 256_000,
              /* maxAudioTrackPlaybackSpeed= */ 1);
  
      // Default buffer duration 0.25s => 0.25 * 256000 / 8 = 8000
      assertThat(bufferSize).isEqualTo(8000 * DEFAULT.ac3BufferMultiplicationFactor);
    }
  
    private static int durationUsToAc3MaxBytes(long durationUs) {
      return (int)
          (durationUs * getMaximumEncodedRateBytesPerSecond(C.ENCODING_AC3) / MICROS_PER_SECOND);
    }
  }
  