text: /**
   * Copyright (c) 2013-present, Facebook, Inc.
   * All rights reserved.
   *
   * This source code is licensed under the BSD-style license found in the
   * LICENSE file in the root directory of this source tree. An additional grant
   * of patent rights can be found in the PATENTS file in the same directory.
   *
   * @format
   * 
   * @emails oncall+draft_js
   */
  
  'use strict';
  
  /**
   * Get offset key from a node or it's child nodes. Return the first offset key
   * found on the DOM tree of given node.
   */
  
  function getSelectionOffsetKeyForNode(node) {
    if (node instanceof Element) {
      var offsetKey = node.getAttribute('data-offset-key');
      if (offsetKey) {
        return offsetKey;
      }
      for (var ii = 0; ii < node.childNodes.length; ii++) {
        var childOffsetKey = getSelectionOffsetKeyForNode(node.childNodes[ii]);
        if (childOffsetKey) {
          return childOffsetKey;
        }
      }
    }
    return null;
  }
  
  module.exports = getSelectionOffsetKeyForNode;