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.ttml;
  
  import android.text.SpannableStringBuilder;
  import com.google.android.exoplayer2.C;
  import com.google.android.exoplayer2.text.Cue;
  import com.google.android.exoplayer2.util.Assertions;
  import java.util.ArrayList;
  import java.util.HashMap;
  import java.util.List;
  import java.util.Map;
  import java.util.Map.Entry;
  import java.util.TreeMap;
  import java.util.TreeSet;
  
  /**
   * A package internal representation of TTML node.
   */
  /* package */ final class TtmlNode {
  
    public static final String TAG_TT = "tt";
    public static final String TAG_HEAD = "head";
    public static final String TAG_BODY = "body";
    public static final String TAG_DIV = "div";
    public static final String TAG_P = "p";
    public static final String TAG_SPAN = "span";
    public static final String TAG_BR = "br";
    public static final String TAG_STYLE = "style";
    public static final String TAG_STYLING = "styling";
    public static final String TAG_LAYOUT = "layout";
    public static final String TAG_REGION = "region";
    public static final String TAG_METADATA = "metadata";
    public static final String TAG_SMPTE_IMAGE = "smpte:image";
    public static final String TAG_SMPTE_DATA = "smpte:data";
    public static final String TAG_SMPTE_INFORMATION = "smpte:information";
  
    public static final String ANONYMOUS_REGION_ID = "";
    public static final String ATTR_ID = "id";
    public static final String ATTR_TTS_ORIGIN = "origin";
    public static final String ATTR_TTS_EXTENT = "extent";
    public static final String ATTR_TTS_DISPLAY_ALIGN = "displayAlign";
    public static final String ATTR_TTS_BACKGROUND_COLOR = "backgroundColor";
    public static final String ATTR_TTS_FONT_STYLE = "fontStyle";
    public static final String ATTR_TTS_FONT_SIZE = "fontSize";
    public static final String ATTR_TTS_FONT_FAMILY = "fontFamily";
    public static final String ATTR_TTS_FONT_WEIGHT = "fontWeight";
    public static final String ATTR_TTS_COLOR = "color";
    public static final String ATTR_TTS_TEXT_DECORATION = "textDecoration";
    public static final String ATTR_TTS_TEXT_ALIGN = "textAlign";
  
    public static final String LINETHROUGH = "linethrough";
    public static final String NO_LINETHROUGH = "nolinethrough";
    public static final String UNDERLINE = "underline";
    public static final String NO_UNDERLINE = "nounderline";
    public static final String ITALIC = "italic";
    public static final String BOLD = "bold";
  
    public static final String LEFT = "left";
    public static final String CENTER = "center";
    public static final String RIGHT = "right";
    public static final String START = "start";
    public static final String END = "end";
  
    public final String tag;
    public final String text;
    public final boolean isTextNode;
    public final long startTimeUs;
    public final long endTimeUs;
    public final TtmlStyle style;
    public final String regionId;
  
    private final String[] styleIds;
    private final HashMap<String, Integer> nodeStartsByRegion;
    private final HashMap<String, Integer> nodeEndsByRegion;
  
    private List<TtmlNode> children;
  
    public static TtmlNode buildTextNode(String text) {
      return new TtmlNode(null, TtmlRenderUtil.applyTextElementSpacePolicy(text), C.TIME_UNSET,
          C.TIME_UNSET, null, null, ANONYMOUS_REGION_ID);
    }
  
    public static TtmlNode buildNode(String tag, long startTimeUs, long endTimeUs,
        TtmlStyle style, String[] styleIds, String regionId) {
      return new TtmlNode(tag, null, startTimeUs, endTimeUs, style, styleIds, regionId);
    }
  
    private TtmlNode(String tag, String text, long startTimeUs, long endTimeUs,
        TtmlStyle style, String[] styleIds, String regionId) {
      this.tag = tag;
      this.text = text;
      this.style = style;
      this.styleIds = styleIds;
      this.isTextNode = text != null;
      this.startTimeUs = startTimeUs;
      this.endTimeUs = endTimeUs;
      this.regionId = Assertions.checkNotNull(regionId);
      nodeStartsByRegion = new HashMap<>();
      nodeEndsByRegion = new HashMap<>();
    }
  
    public boolean isActive(long timeUs) {
      return (startTimeUs == C.TIME_UNSET && endTimeUs == C.TIME_UNSET)
          || (startTimeUs <= timeUs && endTimeUs == C.TIME_UNSET)
          || (startTimeUs == C.TIME_UNSET && timeUs < endTimeUs)
          || (startTimeUs <= timeUs && timeUs < endTimeUs);
    }
  
    public void addChild(TtmlNode child) {
      if (children == null) {
        children = new ArrayList<>();
      }
      children.add(child);
    }
  
    public TtmlNode getChild(int index) {
      if (children == null) {
        throw new IndexOutOfBoundsException();
      }
      return children.get(index);
    }
  
    public int getChildCount() {
      return children == null ? 0 : children.size();
    }
  
    public long[] getEventTimesUs() {
      TreeSet<Long> eventTimeSet = new TreeSet<>();
      getEventTimes(eventTimeSet, false);
      long[] eventTimes = new long[eventTimeSet.size()];
      int i = 0;
      for (long eventTimeUs : eventTimeSet) {
        eventTimes[i++] = eventTimeUs;
      }
      return eventTimes;
    }
  
    private void getEventTimes(TreeSet<Long> out, boolean descendsPNode) {
      boolean isPNode = TAG_P.equals(tag);
      if (descendsPNode || isPNode) {
        if (startTimeUs != C.TIME_UNSET) {
          out.add(startTimeUs);
        }
        if (endTimeUs != C.TIME_UNSET) {
          out.add(endTimeUs);
        }
      }
      if (children == null) {
        return;
      }
      for (int i = 0; i < children.size(); i++) {
        children.get(i).getEventTimes(out, descendsPNode || isPNode);
      }
    }
  
    public String[] getStyleIds() {
      return styleIds;
    }
  
    public List<Cue> getCues(long timeUs, Map<String, TtmlStyle> globalStyles,
        Map<String, TtmlRegion> regionMap) {
      TreeMap<String, SpannableStringBuilder> regionOutputs = new TreeMap<>();
      traverseForText(timeUs, false, regionId, regionOutputs);
      traverseForStyle(globalStyles, regionOutputs);
      List<Cue> cues = new ArrayList<>();
      for (Entry<String, SpannableStringBuilder> entry : regionOutputs.entrySet()) {
        TtmlRegion region = regionMap.get(entry.getKey());
        cues.add(new Cue(cleanUpText(entry.getValue()), null, region.line, region.lineType,
            region.lineAnchor, region.position, Cue.TYPE_UNSET, region.width));
      }
      return cues;
    }
  
    private void traverseForText(long timeUs,  boolean descendsPNode,
        String inheritedRegion, Map<String, SpannableStringBuilder> regionOutputs) {
      nodeStartsByRegion.clear();
      nodeEndsByRegion.clear();
      String resolvedRegionId = regionId;
      if (ANONYMOUS_REGION_ID.equals(resolvedRegionId)) {
        resolvedRegionId = inheritedRegion;
      }
      if (isTextNode && descendsPNode) {
        getRegionOutput(resolvedRegionId, regionOutputs).append(text);
      } else if (TAG_BR.equals(tag) && descendsPNode) {
        getRegionOutput(resolvedRegionId, regionOutputs).append('\n');
      } else if (TAG_METADATA.equals(tag)) {
        // Do nothing.
      } else if (isActive(timeUs)) {
        boolean isPNode = TAG_P.equals(tag);
        for (Entry<String, SpannableStringBuilder> entry : regionOutputs.entrySet()) {
          nodeStartsByRegion.put(entry.getKey(), entry.getValue().length());
        }
        for (int i = 0; i < getChildCount(); i++) {
          getChild(i).traverseForText(timeUs, descendsPNode || isPNode, resolvedRegionId,
              regionOutputs);
        }
        if (isPNode) {
          TtmlRenderUtil.endParagraph(getRegionOutput(resolvedRegionId, regionOutputs));
        }
        for (Entry<String, SpannableStringBuilder> entry : regionOutputs.entrySet()) {
          nodeEndsByRegion.put(entry.getKey(), entry.getValue().length());
        }
      }
    }
  
    private static SpannableStringBuilder getRegionOutput(String resolvedRegionId,
        Map<String, SpannableStringBuilder> regionOutputs) {
      if (!regionOutputs.containsKey(resolvedRegionId)) {
        regionOutputs.put(resolvedRegionId, new SpannableStringBuilder());
      }
      return regionOutputs.get(resolvedRegionId);
    }
  
    private void traverseForStyle(Map<String, TtmlStyle> globalStyles,
        Map<String, SpannableStringBuilder> regionOutputs) {
      for (Entry<String, Integer> entry : nodeEndsByRegion.entrySet()) {
        String regionId = entry.getKey();
        int start = nodeStartsByRegion.containsKey(regionId) ? nodeStartsByRegion.get(regionId) : 0;
        applyStyleToOutput(globalStyles, regionOutputs.get(regionId), start, entry.getValue());
        for (int i = 0; i < getChildCount(); ++i) {
          getChild(i).traverseForStyle(globalStyles, regionOutputs);
        }
      }
    }
  
    private void applyStyleToOutput(Map<String, TtmlStyle> globalStyles,
        SpannableStringBuilder regionOutput, int start, int end) {
      if (start != end) {
        TtmlStyle resolvedStyle = TtmlRenderUtil.resolveStyle(style, styleIds, globalStyles);
        if (resolvedStyle != null) {
          TtmlRenderUtil.applyStylesToSpan(regionOutput, start, end, resolvedStyle);
        }
      }
    }
  
    private SpannableStringBuilder cleanUpText(SpannableStringBuilder builder) {
      // Having joined the text elements, we need to do some final cleanup on the result.
      // 1. Collapse multiple consecutive spaces into a single space.
      int builderLength = builder.length();
      for (int i = 0; i < builderLength; i++) {
        if (builder.charAt(i) == ' ') {
          int j = i + 1;
          while (j < builder.length() && builder.charAt(j) == ' ') {
            j++;
          }
          int spacesToDelete = j - (i + 1);
          if (spacesToDelete > 0) {
            builder.delete(i, i + spacesToDelete);
            builderLength -= spacesToDelete;
          }
        }
      }
      // 2. Remove any spaces from the start of each line.
      if (builderLength > 0 && builder.charAt(0) == ' ') {
        builder.delete(0, 1);
        builderLength--;
      }
      for (int i = 0; i < builderLength - 1; i++) {
        if (builder.charAt(i) == '\n' && builder.charAt(i + 1) == ' ') {
          builder.delete(i + 1, i + 2);
          builderLength--;
        }
      }
      // 3. Remove any spaces from the end of each line.
      if (builderLength > 0 && builder.charAt(builderLength - 1) == ' ') {
        builder.delete(builderLength - 1, builderLength);
        builderLength--;
      }
      for (int i = 0; i < builderLength - 1; i++) {
        if (builder.charAt(i) == ' ' && builder.charAt(i + 1) == '\n') {
          builder.delete(i, i + 1);
          builderLength--;
        }
      }
      // 4. Trim a trailing newline, if there is one.
      if (builderLength > 0 && builder.charAt(builderLength - 1) == '\n') {
        builder.delete(builderLength - 1, builderLength);
        /*builderLength--;*/
      }
      return builder;
    }
  
  }
  