module.js

'use strict';

/**
 * @ngdoc module
 * @name ngAnimate
 * @description
 *
 * The `ngAnimate` module provides support for CSS-based animations (keyframes and transitions) as well as JavaScript-based animations via
 * callback hooks. Animations are not enabled by default, however, by including `ngAnimate` the animation hooks are enabled for an AngularJS app.
 *
 * ## Usage
 * Simply put, there are two ways to make use of animations when ngAnimate is used: by using **CSS** and **JavaScript**. The former works purely based
 * using CSS (by using matching CSS selectors/styles) and the latter triggers animations that are registered via `module.animation()`. For
 * both CSS and JS animations the sole requirement is to have a matching `CSS class` that exists both in the registered animation and within
 * the HTML element that the animation will be triggered on.
 *
 * ## Directive Support
 * The following directives are "animation aware":
 *
 * | Directive                                                                     | Supported Animations                                                      |
 * |-------------------------------------------------------------------------------|---------------------------------------------------------------------------|
 * | {@link ng.directive:form#animations form / ngForm}                            | add and remove ({@link ng.directive:form#css-classes various classes})    |
 * | {@link ngAnimate.directive:ngAnimateSwap#animations ngAnimateSwap}            | enter and leave                                                           |
 * | {@link ng.directive:ngClass#animations ngClass / {{class}​}}  | add and remove                                                            |
 * | {@link ng.directive:ngClassEven#animations ngClassEven}                       | add and remove                                                            |
 * | {@link ng.directive:ngClassOdd#animations ngClassOdd}                         | add and remove                                                            |
 * | {@link ng.directive:ngHide#animations ngHide}                                 | add and remove (the `ng-hide` class)                                      |
 * | {@link ng.directive:ngIf#animations ngIf}                                     | enter and leave                                                           |
 * | {@link ng.directive:ngInclude#animations ngInclude}                           | enter and leave                                                           |
 * | {@link module:ngMessages#animations ngMessage / ngMessageExp}                 | enter and leave                                                           |
 * | {@link module:ngMessages#animations ngMessages}                               | add and remove (the `ng-active`/`ng-inactive` classes)                    |
 * | {@link ng.directive:ngModel#animations ngModel}                               | add and remove ({@link ng.directive:ngModel#css-classes various classes}) |
 * | {@link ng.directive:ngRepeat#animations ngRepeat}                             | enter, leave, and move                                                    |
 * | {@link ng.directive:ngShow#animations ngShow}                                 | add and remove (the `ng-hide` class)                                      |
 * | {@link ng.directive:ngSwitch#animations ngSwitch}                             | enter and leave                                                           |
 * | {@link ngRoute.directive:ngView#animations ngView}                            | enter and leave                                                           |
 *
 * (More information can be found by visiting the documentation associated with each directive.)
 *
 * For a full breakdown of the steps involved during each animation event, refer to the
 * {@link ng.$animate `$animate` API docs}.
 *
 * ## CSS-based Animations
 *
 * CSS-based animations with ngAnimate are unique since they require no JavaScript code at all. By using a CSS class that we reference between our HTML
 * and CSS code we can create an animation that will be picked up by AngularJS when an underlying directive performs an operation.
 *
 * The example below shows how an `enter` animation can be made possible on an element using `ng-if`:
 *
 * ```html
 * <div ng-if="bool" class="fade">
 *    Fade me in out
 * </div>
 * <button ng-click="bool=true">Fade In!</button>
 * <button ng-click="bool=false">Fade Out!</button>
 * ```
 *
 * Notice the CSS class **fade**? We can now create the CSS transition code that references this class:
 *
 * ```css
 * /&#42; The starting CSS styles for the enter animation &#42;/
 * .fade.ng-enter {
 *   transition:0.5s linear all;
 *   opacity:0;
 * }
 *
 * /&#42; The finishing CSS styles for the enter animation &#42;/
 * .fade.ng-enter.ng-enter-active {
 *   opacity:1;
 * }
 * ```
 *
 * The key thing to remember here is that, depending on the animation event (which each of the directives above trigger depending on what's going on) two
 * generated CSS classes will be applied to the element; in the example above we have `.ng-enter` and `.ng-enter-active`. For CSS transitions, the transition
 * code **must** be defined within the starting CSS class (in this case `.ng-enter`). The destination class is what the transition will animate towards.
 *
 * If for example we wanted to create animations for `leave` and `move` (ngRepeat triggers move) then we can do so using the same CSS naming conventions:
 *
 * ```css
 * /&#42; now the element will fade out before it is removed from the DOM &#42;/
 * .fade.ng-leave {
 *   transition:0.5s linear all;
 *   opacity:1;
 * }
 * .fade.ng-leave.ng-leave-active {
 *   opacity:0;
 * }
 * ```
 *
 * We can also make use of **CSS Keyframes** by referencing the keyframe animation within the starting CSS class:
 *
 * ```css
 * /&#42; there is no need to define anything inside of the destination
 * CSS class since the keyframe will take charge of the animation &#42;/
 * .fade.ng-leave {
 *   animation: my_fade_animation 0.5s linear;
 *   -webkit-animation: my_fade_animation 0.5s linear;
 * }
 *
 * @keyframes my_fade_animation {
 *   from { opacity:1; }
 *   to { opacity:0; }
 * }
 *
 * @-webkit-keyframes my_fade_animation {
 *   from { opacity:1; }
 *   to { opacity:0; }
 * }
 * ```
 *
 * Feel free also mix transitions and keyframes together as well as any other CSS classes on the same element.
 *
 * ### CSS Class-based Animations
 *
 * Class-based animations (animations that are triggered via `ngClass`, `ngShow`, `ngHide` and some other directives) have a slightly different
 * naming convention. Class-based animations are basic enough that a standard transition or keyframe can be referenced on the class being added
 * and removed.
 *
 * For example if we wanted to do a CSS animation for `ngHide` then we place an animation on the `.ng-hide` CSS class:
 *
 * ```html
 * <div ng-show="bool" class="fade">
 *   Show and hide me
 * </div>
 * <button ng-click="bool=!bool">Toggle</button>
 *
 * <style>
 * .fade.ng-hide {
 *   transition:0.5s linear all;
 *   opacity:0;
 * }
 * </style>
 * ```
 *
 * All that is going on here with ngShow/ngHide behind the scenes is the `.ng-hide` class is added/removed (when the hidden state is valid). Since
 * ngShow and ngHide are animation aware then we can match up a transition and ngAnimate handles the rest.
 *
 * In addition the addition and removal of the CSS class, ngAnimate also provides two helper methods that we can use to further decorate the animation
 * with CSS styles.
 *
 * ```html
 * <div ng-class="{on:onOff}" class="highlight">
 *   Highlight this box
 * </div>
 * <button ng-click="onOff=!onOff">Toggle</button>
 *
 * <style>
 * .highlight {
 *   transition:0.5s linear all;
 * }
 * .highlight.on-add {
 *   background:white;
 * }
 * .highlight.on {
 *   background:yellow;
 * }
 * .highlight.on-remove {
 *   background:black;
 * }
 * </style>
 * ```
 *
 * We can also make use of CSS keyframes by placing them within the CSS classes.
 *
 *
 * ### CSS Staggering Animations
 * A Staggering animation is a collection of animations that are issued with a slight delay in between each successive operation resulting in a
 * curtain-like effect. The ngAnimate module (versions >=1.2) supports staggering animations and the stagger effect can be
 * performed by creating a **ng-EVENT-stagger** CSS class and attaching that class to the base CSS class used for
 * the animation. The style property expected within the stagger class can either be a **transition-delay** or an
 * **animation-delay** property (or both if your animation contains both transitions and keyframe animations).
 *
 * ```css
 * .my-animation.ng-enter {
 *   /&#42; standard transition code &#42;/
 *   transition: 1s linear all;
 *   opacity:0;
 * }
 * .my-animation.ng-enter-stagger {
 *   /&#42; this will have a 100ms delay between each successive leave animation &#42;/
 *   transition-delay: 0.1s;
 *
 *   /&#42; As of 1.4.4, this must always be set: it signals ngAnimate
 *     to not accidentally inherit a delay property from another CSS class &#42;/
 *   transition-duration: 0s;
 *
 *   /&#42; if you are using animations instead of transitions you should configure as follows:
 *     animation-delay: 0.1s;
 *     animation-duration: 0s; &#42;/
 * }
 * .my-animation.ng-enter.ng-enter-active {
 *   /&#42; standard transition styles &#42;/
 *   opacity:1;
 * }
 * ```
 *
 * Staggering animations work by default in ngRepeat (so long as the CSS class is defined). Outside of ngRepeat, to use staggering animations
 * on your own, they can be triggered by firing multiple calls to the same event on $animate. However, the restrictions surrounding this
 * are that each of the elements must have the same CSS className value as well as the same parent element. A stagger operation
 * will also be reset if one or more animation frames have passed since the multiple calls to `$animate` were fired.
 *
 * The following code will issue the **ng-leave-stagger** event on the element provided:
 *
 * ```js
 * var kids = parent.children();
 *
 * $animate.leave(kids[0]); //stagger index=0
 * $animate.leave(kids[1]); //stagger index=1
 * $animate.leave(kids[2]); //stagger index=2
 * $animate.leave(kids[3]); //stagger index=3
 * $animate.leave(kids[4]); //stagger index=4
 *
 * window.requestAnimationFrame(function() {
 *   //stagger has reset itself
 *   $animate.leave(kids[5]); //stagger index=0
 *   $animate.leave(kids[6]); //stagger index=1
 *
 *   $scope.$digest();
 * });
 * ```
 *
 * Stagger animations are currently only supported within CSS-defined animations.
 *
 * ### The `ng-animate` CSS class
 *
 * When ngAnimate is animating an element it will apply the `ng-animate` CSS class to the element for the duration of the animation.
 * This is a temporary CSS class and it will be removed once the animation is over (for both JavaScript and CSS-based animations).
 *
 * Therefore, animations can be applied to an element using this temporary class directly via CSS.
 *
 * ```css
 * .zipper.ng-animate {
 *   transition:0.5s linear all;
 * }
 * .zipper.ng-enter {
 *   opacity:0;
 * }
 * .zipper.ng-enter.ng-enter-active {
 *   opacity:1;
 * }
 * .zipper.ng-leave {
 *   opacity:1;
 * }
 * .zipper.ng-leave.ng-leave-active {
 *   opacity:0;
 * }
 * ```
 *
 * (Note that the `ng-animate` CSS class is reserved and it cannot be applied on an element directly since ngAnimate will always remove
 * the CSS class once an animation has completed.)
 *
 *
 * ### The `ng-[event]-prepare` class
 *
 * This is a special class that can be used to prevent unwanted flickering / flash of content before
 * the actual animation starts. The class is added as soon as an animation is initialized, but removed
 * before the actual animation starts (after waiting for a $digest).
 * It is also only added for *structural* animations (`enter`, `move`, and `leave`).
 *
 * In practice, flickering can appear when nesting elements with structural animations such as `ngIf`
 * into elements that have class-based animations such as `ngClass`.
 *
 * ```html
 * <div ng-class="{red: myProp}">
 *   <div ng-class="{blue: myProp}">
 *     <div class="message" ng-if="myProp"></div>
 *   </div>
 * </div>
 * ```
 *
 * It is possible that during the `enter` animation, the `.message` div will be briefly visible before it starts animating.
 * In that case, you can add styles to the CSS that make sure the element stays hidden before the animation starts:
 *
 * ```css
 * .message.ng-enter-prepare {
 *   opacity: 0;
 * }
 *
 * ```
 *
 * ## JavaScript-based Animations
 *
 * ngAnimate also allows for animations to be consumed by JavaScript code. The approach is similar to CSS-based animations (where there is a shared
 * CSS class that is referenced in our HTML code) but in addition we need to register the JavaScript animation on the module. By making use of the
 * `module.animation()` module function we can register the animation.
 *
 * Let's see an example of a enter/leave animation using `ngRepeat`:
 *
 * ```html
 * <div ng-repeat="item in items" class="slide">
 *   {{ item }}
 * </div>
 * ```
 *
 * See the **slide** CSS class? Let's use that class to define an animation that we'll structure in our module code by using `module.animation`:
 *
 * ```js
 * myModule.animation('.slide', [function() {
 *   return {
 *     // make note that other events (like addClass/removeClass)
 *     // have different function input parameters
 *     enter: function(element, doneFn) {
 *       jQuery(element).fadeIn(1000, doneFn);
 *
 *       // remember to call doneFn so that AngularJS
 *       // knows that the animation has concluded
 *     },
 *
 *     move: function(element, doneFn) {
 *       jQuery(element).fadeIn(1000, doneFn);
 *     },
 *
 *     leave: function(element, doneFn) {
 *       jQuery(element).fadeOut(1000, doneFn);
 *     }
 *   }
 * }]);
 * ```
 *
 * The nice thing about JS-based animations is that we can inject other services and make use of advanced animation libraries such as
 * greensock.js and velocity.js.
 *
 * If our animation code class-based (meaning that something like `ngClass`, `ngHide` and `ngShow` triggers it) then we can still define
 * our animations inside of the same registered animation, however, the function input arguments are a bit different:
 *
 * ```html
 * <div ng-class="color" class="colorful">
 *   this box is moody
 * </div>
 * <button ng-click="color='red'">Change to red</button>
 * <button ng-click="color='blue'">Change to blue</button>
 * <button ng-click="color='green'">Change to green</button>
 * ```
 *
 * ```js
 * myModule.animation('.colorful', [function() {
 *   return {
 *     addClass: function(element, className, doneFn) {
 *       // do some cool animation and call the doneFn
 *     },
 *     removeClass: function(element, className, doneFn) {
 *       // do some cool animation and call the doneFn
 *     },
 *     setClass: function(element, addedClass, removedClass, doneFn) {
 *       // do some cool animation and call the doneFn
 *     }
 *   }
 * }]);
 * ```
 *
 * ## CSS + JS Animations Together
 *
 * AngularJS 1.4 and higher has taken steps to make the amalgamation of CSS and JS animations more flexible. However, unlike earlier versions of AngularJS,
 * defining CSS and JS animations to work off of the same CSS class will not work anymore. Therefore the example below will only result in **JS animations taking
 * charge of the animation**:
 *
 * ```html
 * <div ng-if="bool" class="slide">
 *   Slide in and out
 * </div>
 * ```
 *
 * ```js
 * myModule.animation('.slide', [function() {
 *   return {
 *     enter: function(element, doneFn) {
 *       jQuery(element).slideIn(1000, doneFn);
 *     }
 *   }
 * }]);
 * ```
 *
 * ```css
 * .slide.ng-enter {
 *   transition:0.5s linear all;
 *   transform:translateY(-100px);
 * }
 * .slide.ng-enter.ng-enter-active {
 *   transform:translateY(0);
 * }
 * ```
 *
 * Does this mean that CSS and JS animations cannot be used together? Do JS-based animations always have higher priority? We can make up for the
 * lack of CSS animations by using the `$animateCss` service to trigger our own tweaked-out, CSS-based animations directly from
 * our own JS-based animation code:
 *
 * ```js
 * myModule.animation('.slide', ['$animateCss', function($animateCss) {
 *   return {
 *     enter: function(element) {
*        // this will trigger `.slide.ng-enter` and `.slide.ng-enter-active`.
 *       return $animateCss(element, {
 *         event: 'enter',
 *         structural: true
 *       });
 *     }
 *   }
 * }]);
 * ```
 *
 * The nice thing here is that we can save bandwidth by sticking to our CSS-based animation code and we don't need to rely on a 3rd-party animation framework.
 *
 * The `$animateCss` service is very powerful since we can feed in all kinds of extra properties that will be evaluated and fed into a CSS transition or
 * keyframe animation. For example if we wanted to animate the height of an element while adding and removing classes then we can do so by providing that
 * data into `$animateCss` directly:
 *
 * ```js
 * myModule.animation('.slide', ['$animateCss', function($animateCss) {
 *   return {
 *     enter: function(element) {
 *       return $animateCss(element, {
 *         event: 'enter',
 *         structural: true,
 *         addClass: 'maroon-setting',
 *         from: { height:0 },
 *         to: { height: 200 }
 *       });
 *     }
 *   }
 * }]);
 * ```
 *
 * Now we can fill in the rest via our transition CSS code:
 *
 * ```css
 * /&#42; the transition tells ngAnimate to make the animation happen &#42;/
 * .slide.ng-enter { transition:0.5s linear all; }
 *
 * /&#42; this extra CSS class will be absorbed into the transition
 * since the $animateCss code is adding the class &#42;/
 * .maroon-setting { background:red; }
 * ```
 *
 * And `$animateCss` will figure out the rest. Just make sure to have the `done()` callback fire the `doneFn` function to signal when the animation is over.
 *
 * To learn more about what's possible be sure to visit the {@link ngAnimate.$animateCss $animateCss service}.
 *
 * ## Animation Anchoring (via `ng-animate-ref`)
 *
 * ngAnimate in AngularJS 1.4 comes packed with the ability to cross-animate elements between
 * structural areas of an application (like views) by pairing up elements using an attribute
 * called `ng-animate-ref`.
 *
 * Let's say for example we have two views that are managed by `ng-view` and we want to show
 * that there is a relationship between two components situated in within these views. By using the
 * `ng-animate-ref` attribute we can identify that the two components are paired together and we
 * can then attach an animation, which is triggered when the view changes.
 *
 * Say for example we have the following template code:
 *
 * ```html
 * <!-- index.html -->
 * <div ng-view class="view-animation">
 * </div>
 *
 * <!-- home.html -->
 * <a href="#/banner-page">
 *   <img src="./banner.jpg" class="banner" ng-animate-ref="banner">
 * </a>
 *
 * <!-- banner-page.html -->
 * <img src="./banner.jpg" class="banner" ng-animate-ref="banner">
 * ```
 *
 * Now, when the view changes (once the link is clicked), ngAnimate will examine the
 * HTML contents to see if there is a match reference between any components in the view
 * that is leaving and the view that is entering. It will scan both the view which is being
 * removed (leave) and inserted (enter) to see if there are any paired DOM elements that
 * contain a matching ref value.
 *
 * The two images match since they share the same ref value. ngAnimate will now create a
 * transport element (which is a clone of the first image element) and it will then attempt
 * to animate to the position of the second image element in the next view. For the animation to
 * work a special CSS class called `ng-anchor` will be added to the transported element.
 *
 * We can now attach a transition onto the `.banner.ng-anchor` CSS class and then
 * ngAnimate will handle the entire transition for us as well as the addition and removal of
 * any changes of CSS classes between the elements:
 *
 * ```css
 * .banner.ng-anchor {
 *   /&#42; this animation will last for 1 second since there are
 *          two phases to the animation (an `in` and an `out` phase) &#42;/
 *   transition:0.5s linear all;
 * }
 * ```
 *
 * We also **must** include animations for the views that are being entered and removed
 * (otherwise anchoring wouldn't be possible since the new view would be inserted right away).
 *
 * ```css
 * .view-animation.ng-enter, .view-animation.ng-leave {
 *   transition:0.5s linear all;
 *   position:fixed;
 *   left:0;
 *   top:0;
 *   width:100%;
 * }
 * .view-animation.ng-enter {
 *   transform:translateX(100%);
 * }
 * .view-animation.ng-leave,
 * .view-animation.ng-enter.ng-enter-active {
 *   transform:translateX(0%);
 * }
 * .view-animation.ng-leave.ng-leave-active {
 *   transform:translateX(-100%);
 * }
 * ```
 *
 * Now we can jump back to the anchor animation. When the animation happens, there are two stages that occur:
 * an `out` and an `in` stage. The `out` stage happens first and that is when the element is animated away
 * from its origin. Once that animation is over then the `in` stage occurs which animates the
 * element to its destination. The reason why there are two animations is to give enough time
 * for the enter animation on the new element to be ready.
 *
 * The example above sets up a transition for both the in and out phases, but we can also target the out or
 * in phases directly via `ng-anchor-out` and `ng-anchor-in`.
 *
 * ```css
 * .banner.ng-anchor-out {
 *   transition: 0.5s linear all;
 *
 *   /&#42; the scale will be applied during the out animation,
 *          but will be animated away when the in animation runs &#42;/
 *   transform: scale(1.2);
 * }
 *
 * .banner.ng-anchor-in {
 *   transition: 1s linear all;
 * }
 * ```
 *
 *
 *
 *
 * ### Anchoring Demo
 *
  <example module="anchoringExample"
           name="anchoringExample"
           id="anchoringExample"
           deps="angular-animate.js;angular-route.js"
           animations="true">
    <file name="index.html">
      <a href="#!/">Home</a>
      <hr />
      <div class="view-container">
        <div ng-view class="view"></div>
      </div>
    </file>
    <file name="script.js">
      angular.module('anchoringExample', ['ngAnimate', 'ngRoute'])
        .config(['$routeProvider', function($routeProvider) {
          $routeProvider.when('/', {
            templateUrl: 'home.html',
            controller: 'HomeController as home'
          });
          $routeProvider.when('/profile/:id', {
            templateUrl: 'profile.html',
            controller: 'ProfileController as profile'
          });
        }])
        .run(['$rootScope', function($rootScope) {
          $rootScope.records = [
            { id: 1, title: 'Miss Beulah Roob' },
            { id: 2, title: 'Trent Morissette' },
            { id: 3, title: 'Miss Ava Pouros' },
            { id: 4, title: 'Rod Pouros' },
            { id: 5, title: 'Abdul Rice' },
            { id: 6, title: 'Laurie Rutherford Sr.' },
            { id: 7, title: 'Nakia McLaughlin' },
            { id: 8, title: 'Jordon Blanda DVM' },
            { id: 9, title: 'Rhoda Hand' },
            { id: 10, title: 'Alexandrea Sauer' }
          ];
        }])
        .controller('HomeController', [function() {
          //empty
        }])
        .controller('ProfileController', ['$rootScope', '$routeParams',
            function ProfileController($rootScope, $routeParams) {
          var index = parseInt($routeParams.id, 10);
          var record = $rootScope.records[index - 1];

          this.title = record.title;
          this.id = record.id;
        }]);
    </file>
    <file name="home.html">
      <h2>Welcome to the home page</h1>
      <p>Please click on an element</p>
      <a class="record"
         ng-href="#!/profile/{{ record.id }}"
         ng-animate-ref="{{ record.id }}"
         ng-repeat="record in records">
        {{ record.title }}
      </a>
    </file>
    <file name="profile.html">
      <div class="profile record" ng-animate-ref="{{ profile.id }}">
        {{ profile.title }}
      </div>
    </file>
    <file name="animations.css">
      .record {
        display:block;
        font-size:20px;
      }
      .profile {
        background:black;
        color:white;
        font-size:100px;
      }
      .view-container {
        position:relative;
      }
      .view-container > .view.ng-animate {
        position:absolute;
        top:0;
        left:0;
        width:100%;
        min-height:500px;
      }
      .view.ng-enter, .view.ng-leave,
      .record.ng-anchor {
        transition:0.5s linear all;
      }
      .view.ng-enter {
        transform:translateX(100%);
      }
      .view.ng-enter.ng-enter-active, .view.ng-leave {
        transform:translateX(0%);
      }
      .view.ng-leave.ng-leave-active {
        transform:translateX(-100%);
      }
      .record.ng-anchor-out {
        background:red;
      }
    </file>
  </example>
 *
 * ### How is the element transported?
 *
 * When an anchor animation occurs, ngAnimate will clone the starting element and position it exactly where the starting
 * element is located on screen via absolute positioning. The cloned element will be placed inside of the root element
 * of the application (where ng-app was defined) and all of the CSS classes of the starting element will be applied. The
 * element will then animate into the `out` and `in` animations and will eventually reach the coordinates and match
 * the dimensions of the destination element. During the entire animation a CSS class of `.ng-animate-shim` will be applied
 * to both the starting and destination elements in order to hide them from being visible (the CSS styling for the class
 * is: `visibility:hidden`). Once the anchor reaches its destination then it will be removed and the destination element
 * will become visible since the shim class will be removed.
 *
 * ### How is the morphing handled?
 *
 * CSS Anchoring relies on transitions and keyframes and the internal code is intelligent enough to figure out
 * what CSS classes differ between the starting element and the destination element. These different CSS classes
 * will be added/removed on the anchor element and a transition will be applied (the transition that is provided
 * in the anchor class). Long story short, ngAnimate will figure out what classes to add and remove which will
 * make the transition of the element as smooth and automatic as possible. Be sure to use simple CSS classes that
 * do not rely on DOM nesting structure so that the anchor element appears the same as the starting element (since
 * the cloned element is placed inside of root element which is likely close to the body element).
 *
 * Note that if the root element is on the `<html>` element then the cloned node will be placed inside of body.
 *
 *
 * ## Using $animate in your directive code
 *
 * So far we've explored how to feed in animations into an AngularJS application, but how do we trigger animations within our own directives in our application?
 * By injecting the `$animate` service into our directive code, we can trigger structural and class-based hooks which can then be consumed by animations. Let's
 * imagine we have a greeting box that shows and hides itself when the data changes
 *
 * ```html
 * <greeting-box active="onOrOff">Hi there</greeting-box>
 * ```
 *
 * ```js
 * ngModule.directive('greetingBox', ['$animate', function($animate) {
 *   return function(scope, element, attrs) {
 *     attrs.$observe('active', function(value) {
 *       value ? $animate.addClass(element, 'on') : $animate.removeClass(element, 'on');
 *     });
 *   });
 * }]);
 * ```
 *
 * Now the `on` CSS class is added and removed on the greeting box component. Now if we add a CSS class on top of the greeting box element
 * in our HTML code then we can trigger a CSS or JS animation to happen.
 *
 * ```css
 * /&#42; normally we would create a CSS class to reference on the element &#42;/
 * greeting-box.on { transition:0.5s linear all; background:green; color:white; }
 * ```
 *
 * The `$animate` service contains a variety of other methods like `enter`, `leave`, `animate` and `setClass`. To learn more about what's
 * possible be sure to visit the {@link ng.$animate $animate service API page}.
 *
 *
 * ## Callbacks and Promises
 *
 * When `$animate` is called it returns a promise that can be used to capture when the animation has ended. Therefore if we were to trigger
 * an animation (within our directive code) then we can continue performing directive and scope related activities after the animation has
 * ended by chaining onto the returned promise that animation method returns.
 *
 * ```js
 * // somewhere within the depths of the directive
 * $animate.enter(element, parent).then(function() {
 *   //the animation has completed
 * });
 * ```
 *
 * (Note that earlier versions of AngularJS prior to v1.4 required the promise code to be wrapped using `$scope.$apply(...)`. This is not the case
 * anymore.)
 *
 * In addition to the animation promise, we can also make use of animation-related callbacks within our directives and controller code by registering
 * an event listener using the `$animate` service. Let's say for example that an animation was triggered on our view
 * routing controller to hook into that:
 *
 * ```js
 * ngModule.controller('HomePageController', ['$animate', function($animate) {
 *   $animate.on('enter', ngViewElement, function(element) {
 *     // the animation for this route has completed
 *   }]);
 * }])
 * ```
 *
 * (Note that you will need to trigger a digest within the callback to get AngularJS to notice any scope-related changes.)
 */

var copy;
var extend;
var forEach;
var isArray;
var isDefined;
var isElement;
var isFunction;
var isObject;
var isString;
var isUndefined;
var jqLite;
var noop;

/**
 * @ngdoc service
 * @name $animate
 * @kind object
 *
 * @description
 * The ngAnimate `$animate` service documentation is the same for the core `$animate` service.
 *
 * Click here {@link ng.$animate to learn more about animations with `$animate`}.
 */
angular.module('ngAnimate', [], function initAngularHelpers() {
  // Access helpers from AngularJS core.
  // Do it inside a `config` block to ensure `window.angular` is available.
  noop        = angular.noop;
  copy        = angular.copy;
  extend      = angular.extend;
  jqLite      = angular.element;
  forEach     = angular.forEach;
  isArray     = angular.isArray;
  isString    = angular.isString;
  isObject    = angular.isObject;
  isUndefined = angular.isUndefined;
  isDefined   = angular.isDefined;
  isFunction  = angular.isFunction;
  isElement   = angular.isElement;
})
  .info({ angularVersion: '"NG_VERSION_FULL"' })
  .directive('ngAnimateSwap', ngAnimateSwapDirective)

  .directive('ngAnimateChildren', $$AnimateChildrenDirective)
  .factory('$$rAFScheduler', $$rAFSchedulerFactory)

  .provider('$$animateQueue', $$AnimateQueueProvider)
  .provider('$$animation', $$AnimationProvider)

  .provider('$animateCss', $AnimateCssProvider)
  .provider('$$animateCssDriver', $$AnimateCssDriverProvider)

  .provider('$$animateJs', $$AnimateJsProvider)
  .provider('$$animateJsDriver', $$AnimateJsDriverProvider);