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.text.webvtt;
  
  import android.text.SpannableStringBuilder;
  import com.google.android.exoplayer2.C;
  import com.google.android.exoplayer2.text.Cue;
  import com.google.android.exoplayer2.text.Subtitle;
  import com.google.android.exoplayer2.util.Assertions;
  import com.google.android.exoplayer2.util.Util;
  import java.util.ArrayList;
  import java.util.Arrays;
  import java.util.Collections;
  import java.util.List;
  
  /**
   * A representation of a WebVTT subtitle.
   */
  /* package */ final class WebvttSubtitle implements Subtitle {
  
    private final List<WebvttCue> cues;
    private final int numCues;
    private final long[] cueTimesUs;
    private final long[] sortedCueTimesUs;
  
    /**
     * @param cues A list of the cues in this subtitle.
     */
    public WebvttSubtitle(List<WebvttCue> cues) {
      this.cues = cues;
      numCues = cues.size();
      cueTimesUs = new long[2 * numCues];
      for (int cueIndex = 0; cueIndex < numCues; cueIndex++) {
        WebvttCue cue = cues.get(cueIndex);
        int arrayIndex = cueIndex * 2;
        cueTimesUs[arrayIndex] = cue.startTime;
        cueTimesUs[arrayIndex + 1] = cue.endTime;
      }
      sortedCueTimesUs = Arrays.copyOf(cueTimesUs, cueTimesUs.length);
      Arrays.sort(sortedCueTimesUs);
    }
  
    @Override
    public int getNextEventTimeIndex(long timeUs) {
      int index = Util.binarySearchCeil(sortedCueTimesUs, timeUs, false, false);
      return index < sortedCueTimesUs.length ? index : C.INDEX_UNSET;
    }
  
    @Override
    public int getEventTimeCount() {
      return sortedCueTimesUs.length;
    }
  
    @Override
    public long getEventTime(int index) {
      Assertions.checkArgument(index >= 0);
      Assertions.checkArgument(index < sortedCueTimesUs.length);
      return sortedCueTimesUs[index];
    }
  
    @Override
    public List<Cue> getCues(long timeUs) {
      ArrayList<Cue> list = null;
      WebvttCue firstNormalCue = null;
      SpannableStringBuilder normalCueTextBuilder = null;
  
      for (int i = 0; i < numCues; i++) {
        if ((cueTimesUs[i * 2] <= timeUs) && (timeUs < cueTimesUs[i * 2 + 1])) {
          if (list == null) {
            list = new ArrayList<>();
          }
          WebvttCue cue = cues.get(i);
          if (cue.isNormalCue()) {
            // we want to merge all of the normal cues into a single cue to ensure they are drawn
            // correctly (i.e. don't overlap) and to emulate roll-up, but only if there are multiple
            // normal cues, otherwise we can just append the single normal cue
            if (firstNormalCue == null) {
              firstNormalCue = cue;
            } else if (normalCueTextBuilder == null) {
              normalCueTextBuilder = new SpannableStringBuilder();
              normalCueTextBuilder.append(firstNormalCue.text).append("\n").append(cue.text);
            } else {
              normalCueTextBuilder.append("\n").append(cue.text);
            }
          } else {
            list.add(cue);
          }
        }
      }
      if (normalCueTextBuilder != null) {
        // there were multiple normal cues, so create a new cue with all of the text
        list.add(new WebvttCue(normalCueTextBuilder));
      } else if (firstNormalCue != null) {
        // there was only a single normal cue, so just add it to the list
        list.add(firstNormalCue);
      }
  
      if (list != null) {
        return list;
      } else {
        return Collections.emptyList();
      }
    }
  
  }
  