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.source;
  
  import com.google.android.exoplayer2.C;
  
  /**
   * A {@link SequenceableLoader} that encapsulates multiple other {@link SequenceableLoader}s.
   */
  public class CompositeSequenceableLoader implements SequenceableLoader {
  
    protected final SequenceableLoader[] loaders;
  
    public CompositeSequenceableLoader(SequenceableLoader[] loaders) {
      this.loaders = loaders;
    }
  
    @Override
    public final long getBufferedPositionUs() {
      long bufferedPositionUs = Long.MAX_VALUE;
      for (SequenceableLoader loader : loaders) {
        long loaderBufferedPositionUs = loader.getBufferedPositionUs();
        if (loaderBufferedPositionUs != C.TIME_END_OF_SOURCE) {
          bufferedPositionUs = Math.min(bufferedPositionUs, loaderBufferedPositionUs);
        }
      }
      return bufferedPositionUs == Long.MAX_VALUE ? C.TIME_END_OF_SOURCE : bufferedPositionUs;
    }
  
    @Override
    public final long getNextLoadPositionUs() {
      long nextLoadPositionUs = Long.MAX_VALUE;
      for (SequenceableLoader loader : loaders) {
        long loaderNextLoadPositionUs = loader.getNextLoadPositionUs();
        if (loaderNextLoadPositionUs != C.TIME_END_OF_SOURCE) {
          nextLoadPositionUs = Math.min(nextLoadPositionUs, loaderNextLoadPositionUs);
        }
      }
      return nextLoadPositionUs == Long.MAX_VALUE ? C.TIME_END_OF_SOURCE : nextLoadPositionUs;
    }
  
    @Override
    public final void reevaluateBuffer(long positionUs) {
      for (SequenceableLoader loader : loaders) {
        loader.reevaluateBuffer(positionUs);
      }
    }
  
    @Override
    public boolean continueLoading(long positionUs) {
      boolean madeProgress = false;
      boolean madeProgressThisIteration;
      do {
        madeProgressThisIteration = false;
        long nextLoadPositionUs = getNextLoadPositionUs();
        if (nextLoadPositionUs == C.TIME_END_OF_SOURCE) {
          break;
        }
        for (SequenceableLoader loader : loaders) {
          long loaderNextLoadPositionUs = loader.getNextLoadPositionUs();
          boolean isLoaderBehind =
              loaderNextLoadPositionUs != C.TIME_END_OF_SOURCE
                  && loaderNextLoadPositionUs <= positionUs;
          if (loaderNextLoadPositionUs == nextLoadPositionUs || isLoaderBehind) {
            madeProgressThisIteration |= loader.continueLoading(positionUs);
          }
        }
        madeProgress |= madeProgressThisIteration;
      } while (madeProgressThisIteration);
      return madeProgress;
    }
  
  }
  