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.extractor.mp3;
  
  import com.google.android.exoplayer2.C;
  import com.google.android.exoplayer2.audio.MpegAudioUtil;
  import com.google.android.exoplayer2.extractor.ConstantBitrateSeekMap;
  
  /**
   * MP3 seeker that doesn't rely on metadata and seeks assuming the source has a constant bitrate.
   */
  /* package */ final class ConstantBitrateSeeker extends ConstantBitrateSeekMap implements Seeker {
  
    /**
     * @param inputLength The length of the stream in bytes, or {@link C#LENGTH_UNSET} if unknown.
     * @param firstFramePosition The position of the first frame in the stream.
     * @param mpegAudioHeader The MPEG audio header associated with the first frame.
     * @param allowSeeksIfLengthUnknown Whether to allow seeking even if the length of the content is
     *     unknown.
     */
    public ConstantBitrateSeeker(
        long inputLength,
        long firstFramePosition,
        MpegAudioUtil.Header mpegAudioHeader,
        boolean allowSeeksIfLengthUnknown) {
      // Set the seeker frame size to the size of the first frame (even though some constant bitrate
      // streams have variable frame sizes) to avoid the need to re-synchronize for constant frame
      // size streams.
      super(
          inputLength,
          firstFramePosition,
          mpegAudioHeader.bitrate,
          mpegAudioHeader.frameSize,
          allowSeeksIfLengthUnknown);
    }
  
    @Override
    public long getTimeUs(long position) {
      return getTimeUsAtPosition(position);
    }
  
    @Override
    public long getDataEndPosition() {
      return C.POSITION_UNSET;
    }
  }
  