Function nodeAndOffsetInLineMap

samples/common/codehighlight/codemirror.js:2431–2467

(map, ch, bias)

  var nullRect = {left: 0, right: 0, top: 0, bottom: 0};

  function nodeAndOffsetInLineMap(map, ch, bias) {
    var node, start, end, collapse, mStart, mEnd;
    // First, search the line map for the text node corresponding to,
    // or closest to, the target character.
    for (var i = 0; i < map.length; i += 3) {
      mStart = map[i];
      mEnd = map[i + 1];
      if (ch < mStart) {
        start = 0; end = 1;
        collapse = "left";
      } else if (ch < mEnd) {
        start = ch - mStart;
        end = start + 1;
      } else if (i == map.length - 3 || ch == mEnd && map[i + 3] > ch) {
        end = mEnd - mStart;
        start = end - 1;
        if (ch >= mEnd) { collapse = "right"; }
      }
      if (start != null) {
        node = map[i + 2];
        if (mStart == mEnd && bias == (node.insertLeft ? "left" : "right"))
          { collapse = bias; }
        if (bias == "left" && start == 0)
          { while (i && map[i - 2] == map[i - 3] && map[i - 1].insertLeft) {
            node = map[(i -= 3) + 2];
            collapse = "left";
          } }
        if (bias == "right" && start == mEnd - mStart)
          { while (i < map.length - 3 && map[i + 3] == map[i + 4] && !map[i + 5].insertLeft) {
            node = map[(i += 3) + 2];
            collapse = "right";
          } }
        break
      }
    }
    return {node: node, start: start, end: end, collapse: collapse, coverStart: mStart, coverEnd: mEnd}
  }

  function getUsefulRect(rects, bias) {
    var rect = nullRect;