spiritjs/lib/utils/xpath.js

The animation toolkit for the web

"use strict";

exports.__esModule = true;
exports.getElement = getElement;
exports.getExpression = getExpression;
var _is = require("./is");
var _debug = _interopRequireDefault(require("./debug"));
function _interopRequireDefault(e) { return e && e.__esModule ? e : { "default": e }; }
/**
 * Get DOM representation for an element.
 *
 * @param   {Element}              element
 * @param   {null|undefined|Node}  nodeContext
 * @returns {string|null}
 */
function getExpression(element, nodeContext) {
  if (nodeContext === void 0) {
    nodeContext = null;
  }
  var paths = [];
  var isNodeContext = function isNodeContext() {
    if (!nodeContext) {
      return true;
    }
    return nodeContext !== element;
  };
  while (element.nodeType === window.Node.ELEMENT_NODE && isNodeContext()) {
    var index = 0;
    for (var sibling = element.previousSibling; sibling; sibling = sibling.previousSibling) {
      if (sibling.nodeType === window.Node.DOCUMENT_TYPE_NODE) {
        continue;
      }
      if (sibling.nodeName === element.nodeName) {
        ++index;
      }
    }
    var tagName = element.nodeName.toLowerCase();
    var pathIndex = "[" + (index + 1) + "]";
    if ((0, _is.isSVG)(element)) {
      tagName = "*[local-name()='" + tagName + "']";
    }
    paths.unshift(tagName + pathIndex);
    element = element.parentNode;
  }
  if (paths.length === 0) {
    return null;
  }
  return nodeContext ? paths.join('/') : "/" + paths.join('/');
}

/**
 * Get an element from expression
 *
 * @param   {string} expression
 * @param   {Node}   nodeContext
 * @returns {Node|null}
 */
function getElement(expression, nodeContext) {
  if (nodeContext === void 0) {
    nodeContext = null;
  }
  if (!nodeContext) {
    nodeContext = document.body || document.documentElement;
  }
  try {
    var evaluated = document.evaluate(expression, nodeContext, null, window.XPathResult.ANY_TYPE, null);
    return evaluated.iterateNext();
  } catch (err) {
    if ((0, _debug["default"])()) {
      console.error('Cannot get element from expression: ', expression);
      console.error(err.stack);
    }
  }
  return null;
}