draft-js/lib/getRangeBoundingClientRect.js

/**
 * Copyright (c) Facebook, Inc. and its affiliates.
 *
 * This source code is licensed under the MIT license found in the
 * LICENSE file in the root directory of this source tree.
 *
 * @format
 * 
 * @emails oncall+draft_js
 */
'use strict';

var getRangeClientRects = require("./getRangeClientRects");

/**
 * Like range.getBoundingClientRect() but normalizes for browser bugs.
 */
function getRangeBoundingClientRect(range) {
  // "Return a DOMRect object describing the smallest rectangle that includes
  // the first rectangle in list and all of the remaining rectangles of which
  // the height or width is not zero."
  // http://www.w3.org/TR/cssom-view/#dom-range-getboundingclientrect
  var rects = getRangeClientRects(range);
  var top = 0;
  var right = 0;
  var bottom = 0;
  var left = 0;

  if (rects.length) {
    // If the first rectangle has 0 width, we use the second, this is needed
    // because Chrome renders a 0 width rectangle when the selection contains
    // a line break.
    if (rects.length > 1 && rects[0].width === 0) {
      var _rects$ = rects[1];
      top = _rects$.top;
      right = _rects$.right;
      bottom = _rects$.bottom;
      left = _rects$.left;
    } else {
      var _rects$2 = rects[0];
      top = _rects$2.top;
      right = _rects$2.right;
      bottom = _rects$2.bottom;
      left = _rects$2.left;
    }

    for (var ii = 1; ii < rects.length; ii++) {
      var rect = rects[ii];

      if (rect.height !== 0 && rect.width !== 0) {
        top = Math.min(top, rect.top);
        right = Math.max(right, rect.right);
        bottom = Math.max(bottom, rect.bottom);
        left = Math.min(left, rect.left);
      }
    }
  }

  return {
    top: top,
    right: right,
    bottom: bottom,
    left: left,
    width: right - left,
    height: bottom - top
  };
}

module.exports = getRangeBoundingClientRect;