text: // Copyright 2006 The Closure Library Authors. All Rights Reserved.
  //
  // 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.
  
  /**
   * @fileoverview Utilities for adding, removing and setting classes.  Prefer
   * {@link goog.dom.classlist} over these utilities since goog.dom.classlist
   * conforms closer to the semantics of Element.classList, is faster (uses
   * native methods rather than parsing strings on every call) and compiles
   * to smaller code as a result.
   *
   * Note: these utilities are meant to operate on HTMLElements and
   * will not work on elements with differing interfaces (such as SVGElements).
   *
   * @author arv@google.com (Erik Arvidsson)
   */
  
  
  goog.provide('goog.dom.classes');
  
  goog.require('goog.array');
  
  
  /**
   * Sets the entire class name of an element.
   * @param {Node} element DOM node to set class of.
   * @param {string} className Class name(s) to apply to element.
   * @deprecated Use goog.dom.classlist.set instead.
   */
  goog.dom.classes.set = function(element, className) {
    element.className = className;
  };
  
  
  /**
   * Gets an array of class names on an element
   * @param {Node} element DOM node to get class of.
   * @return {!Array<?>} Class names on {@code element}. Some browsers add extra
   *     properties to the array. Do not depend on any of these!
   * @deprecated Use goog.dom.classlist.get instead.
   */
  goog.dom.classes.get = function(element) {
    var className = element.className;
    // Some types of elements don't have a className in IE (e.g. iframes).
    // Furthermore, in Firefox, className is not a string when the element is
    // an SVG element.
    return goog.isString(className) && className.match(/\S+/g) || [];
  };
  
  
  /**
   * Adds a class or classes to an element. Does not add multiples of class names.
   * @param {Node} element DOM node to add class to.
   * @param {...string} var_args Class names to add.
   * @return {boolean} Whether class was added (or all classes were added).
   * @deprecated Use goog.dom.classlist.add or goog.dom.classlist.addAll instead.
   */
  goog.dom.classes.add = function(element, var_args) {
    var classes = goog.dom.classes.get(element);
    var args = goog.array.slice(arguments, 1);
    var expectedCount = classes.length + args.length;
    goog.dom.classes.add_(classes, args);
    goog.dom.classes.set(element, classes.join(' '));
    return classes.length == expectedCount;
  };
  
  
  /**
   * Removes a class or classes from an element.
   * @param {Node} element DOM node to remove class from.
   * @param {...string} var_args Class name(s) to remove.
   * @return {boolean} Whether all classes in {@code var_args} were found and
   *     removed.
   * @deprecated Use goog.dom.classlist.remove or goog.dom.classlist.removeAll
   *     instead.
   */
  goog.dom.classes.remove = function(element, var_args) {
    var classes = goog.dom.classes.get(element);
    var args = goog.array.slice(arguments, 1);
    var newClasses = goog.dom.classes.getDifference_(classes, args);
    goog.dom.classes.set(element, newClasses.join(' '));
    return newClasses.length == classes.length - args.length;
  };
  
  
  /**
   * Helper method for {@link goog.dom.classes.add} and
   * {@link goog.dom.classes.addRemove}. Adds one or more classes to the supplied
   * classes array.
   * @param {Array<string>} classes All class names for the element, will be
   *     updated to have the classes supplied in {@code args} added.
   * @param {Array<string>} args Class names to add.
   * @private
   */
  goog.dom.classes.add_ = function(classes, args) {
    for (var i = 0; i < args.length; i++) {
      if (!goog.array.contains(classes, args[i])) {
        classes.push(args[i]);
      }
    }
  };
  
  
  /**
   * Helper method for {@link goog.dom.classes.remove} and
   * {@link goog.dom.classes.addRemove}. Calculates the difference of two arrays.
   * @param {!Array<string>} arr1 First array.
   * @param {!Array<string>} arr2 Second array.
   * @return {!Array<string>} The first array without the elements of the second
   *     array.
   * @private
   */
  goog.dom.classes.getDifference_ = function(arr1, arr2) {
    return goog.array.filter(arr1, function(item) {
      return !goog.array.contains(arr2, item);
    });
  };
  
  
  /**
   * Switches a class on an element from one to another without disturbing other
   * classes. If the fromClass isn't removed, the toClass won't be added.
   * @param {Node} element DOM node to swap classes on.
   * @param {string} fromClass Class to remove.
   * @param {string} toClass Class to add.
   * @return {boolean} Whether classes were switched.
   * @deprecated Use goog.dom.classlist.swap instead.
   */
  goog.dom.classes.swap = function(element, fromClass, toClass) {
    var classes = goog.dom.classes.get(element);
  
    var removed = false;
    for (var i = 0; i < classes.length; i++) {
      if (classes[i] == fromClass) {
        goog.array.splice(classes, i--, 1);
        removed = true;
      }
    }
  
    if (removed) {
      classes.push(toClass);
      goog.dom.classes.set(element, classes.join(' '));
    }
  
    return removed;
  };
  
  
  /**
   * Adds zero or more classes to an element and removes zero or more as a single
   * operation. Unlike calling {@link goog.dom.classes.add} and
   * {@link goog.dom.classes.remove} separately, this is more efficient as it only
   * parses the class property once.
   *
   * If a class is in both the remove and add lists, it will be added. Thus,
   * you can use this instead of {@link goog.dom.classes.swap} when you have
   * more than two class names that you want to swap.
   *
   * @param {Node} element DOM node to swap classes on.
   * @param {?(string|Array<string>)} classesToRemove Class or classes to
   *     remove, if null no classes are removed.
   * @param {?(string|Array<string>)} classesToAdd Class or classes to add, if
   *     null no classes are added.
   * @deprecated Use goog.dom.classlist.addRemove instead.
   */
  goog.dom.classes.addRemove = function(element, classesToRemove, classesToAdd) {
    var classes = goog.dom.classes.get(element);
    if (goog.isString(classesToRemove)) {
      goog.array.remove(classes, classesToRemove);
    } else if (goog.isArray(classesToRemove)) {
      classes = goog.dom.classes.getDifference_(classes, classesToRemove);
    }
  
    if (goog.isString(classesToAdd) &&
        !goog.array.contains(classes, classesToAdd)) {
      classes.push(classesToAdd);
    } else if (goog.isArray(classesToAdd)) {
      goog.dom.classes.add_(classes, classesToAdd);
    }
  
    goog.dom.classes.set(element, classes.join(' '));
  };
  
  
  /**
   * Returns true if an element has a class.
   * @param {Node} element DOM node to test.
   * @param {string} className Class name to test for.
   * @return {boolean} Whether element has the class.
   * @deprecated Use goog.dom.classlist.contains instead.
   */
  goog.dom.classes.has = function(element, className) {
    return goog.array.contains(goog.dom.classes.get(element), className);
  };
  
  
  /**
   * Adds or removes a class depending on the enabled argument.
   * @param {Node} element DOM node to add or remove the class on.
   * @param {string} className Class name to add or remove.
   * @param {boolean} enabled Whether to add or remove the class (true adds,
   *     false removes).
   * @deprecated Use goog.dom.classlist.enable or goog.dom.classlist.enableAll
   *     instead.
   */
  goog.dom.classes.enable = function(element, className, enabled) {
    if (enabled) {
      goog.dom.classes.add(element, className);
    } else {
      goog.dom.classes.remove(element, className);
    }
  };
  
  
  /**
   * Removes a class if an element has it, and adds it the element doesn't have
   * it.  Won't affect other classes on the node.
   * @param {Node} element DOM node to toggle class on.
   * @param {string} className Class to toggle.
   * @return {boolean} True if class was added, false if it was removed
   *     (in other words, whether element has the class after this function has
   *     been called).
   * @deprecated Use goog.dom.classlist.toggle instead.
   */
  goog.dom.classes.toggle = function(element, className) {
    var add = !goog.dom.classes.has(element, className);
    goog.dom.classes.enable(element, className, add);
    return add;
  };
  