    /**
     * @class Ext.app.Controller
     * @constructor
     *
     * Controllers are the glue that binds an application together. All they really do is listen for events (usually from
     * views) and take some action. Here's how we might create a Controller to manage Users:
     *
     *     Ext.define('MyApp.controller.Users', {
     *         extend: 'Ext.app.Controller',
     *
     *         init: function() {
     *             console.log('Initialized Users! This happens before the Application launch function is called');
     *         }
     *     });
     *
     * The init function is a special method that is called when your application boots. It is called before the
     * {@link Ext.app.Application Application}'s launch function is executed so gives a hook point to run any code before
     * your Viewport is created.
     *
     * The init function is a great place to set up how your controller interacts with the view, and is usually used in
     * conjunction with another Controller function - {@link Ext.app.Controller#control control}. The control function
     * makes it easy to listen to events on your view classes and take some action with a handler function. Let's update
     * our Users controller to tell us when the panel is rendered:
     *
     *     Ext.define('MyApp.controller.Users', {
     *         extend: 'Ext.app.Controller',
     *
     *         init: function() {
     *             this.control({
     *                 'viewport > panel': {
     *                     render: this.onPanelRendered
     *                 }
     *             });
     *         },
     *
     *         onPanelRendered: function() {
     *             console.log('The panel was rendered');
     *         }
     *     });
     *
     * We've updated the init function to use this.control to set up listeners on views in our application. The control
     * function uses the new ComponentQuery engine to quickly and easily get references to components on the page. If you
     * are not familiar with ComponentQuery yet, be sure to check out THIS GUIDE for a full explanation. In brief though,
     * it allows us to pass a CSS-like selector that will find every matching component on the page.
     *
     * In our init function above we supplied 'viewport > panel', which translates to "find me every Panel that is a direct
     * child of a Viewport". We then supplied an object that maps event names (just 'render' in this case) to handler
     * functions. The overall effect is that whenever any component that matches our selector fires a 'render' event, our
     * onPanelRendered function is called.
     *
     * <u>Using refs</u>
     *
     * One of the most useful parts of Controllers is the new ref system. These use the new {@link Ext.ComponentQuery} to
     * make it really easy to get references to Views on your page. Let's look at an example of this now:
     *
     * Ext.define('MyApp.controller.Users', {
         extend: 'Ext.app.Controller',

         refs: [
             {
                 ref: 'list',
                 selector: 'grid'
             }
         ],

         init: function() {
             this.control({
                 'button': {
                     click: this.refreshGrid
                 }
             });
         },

         refreshGrid: function() {
             this.getList().store.load();
         }
     });
     *
     * This example assumes the existence of a {@link Ext.grid.Panel Grid} on the page, which contains a single button to
     * refresh the Grid when clicked. In our refs array, we set up a reference to the grid. There are two parts to this -
     * the 'selector', which is a {@link Ext.ComponentQuery ComponentQuery} selector which finds any grid on the page and
     * assigns it to the reference 'list'.
     *
     * By giving the reference a name, we get a number of things for free. The first is the getList function that we use in
     * the refreshGrid method above. This is generated automatically by the Controller based on the name of our ref, which
     * was capitalized and prepended with get to go from 'list' to 'getList'.
     *
     * The way this works is that the first time getList is called by your code, the ComponentQuery selector is run and the
     * first component that matches the selector ('grid' in this case) will be returned. All future calls to getList will
     * use a cached reference to that grid. Usually it is advised to use a specific ComponentQuery selector that will only
     * match a single View in your application (in the case above our selector will match any grid on the page).
     *
     * Bringing it all together, our init function is called when the application boots, at which time we call this.control
     * to listen to any click on a {@link Ext.button.Button button} and call our refreshGrid function (again, this will
     * match any button on the page so we advise a more specific selector than just 'button', but have left it this way for
     * simplicity). When the button is clicked we use out getList function to refresh the grid.
     *
     * You can create any number of refs and control any number of components this way, simply adding more functions to
     * your Controller as you go. For an example of real-world usage of Controllers see the Feed Viewer example in the
     * examples/app/feed-viewer folder in the SDK download.
     *
     * <u>Generated getter methods</u>
     *
     * Refs aren't the only thing that generate convenient getter methods. Controllers often have to deal with Models and
     * Stores so the framework offers a couple of easy ways to get access to those too. Let's look at another example:
     *
     * Ext.define('MyApp.controller.Users', {
         extend: 'Ext.app.Controller',

         models: ['User'],
         stores: ['AllUsers', 'AdminUsers'],

         init: function() {
             var User = this.getUserModel(),
                 allUsers = this.getAllUsersStore();

             var ed = new User({name: 'Ed'});
             allUsers.add(ed);
         }
     });
     *
     * By specifying Models and Stores that the Controller cares about, it again dynamically loads them from the appropriate
     * locations (app/model/User.js, app/store/AllUsers.js and app/store/AdminUsers.js in this case) and creates getter
     * functions for them all. The example above will create a new User model instance and add it to the AllUsers Store.
     * Of course, you could do anything in this function but in this case we just did something simple to demonstrate the
     * functionality.
     *
     * <u>Further Reading</u>
     *
     * For more information about writing Ext JS 4 applications, please see the <a href="../guide/application_architecture">
     * application architecture guide</a>. Also see the {@link Ext.app.Application} documentation.
     *
     * @markdown
     * @docauthor Ed Spencer
     */
    Ext.define('Ext.app.Controller', {
        /**
         * @cfg {Object} id The id of this controller. You can use this id when dispatching.
         */

        mixins: {
            observable: 'Ext.util.Observable'
        },

        onClassExtended: function(cls, data) {
            var className = Ext.getClassName(cls),
                match = className.match(/^(.*)\.controller\./);

            if (match !== null) {
                var namespace = Ext.Loader.getPrefix(className) || match[1],
                    onBeforeClassCreated = data.onBeforeClassCreated,
                    requires = [],
                    modules = ['model', 'view', 'store'],
                    prefix;

                data.onBeforeClassCreated = function(cls, data) {
                    var i, ln, module,
                        items, j, subLn, item;

                    for (i = 0,ln = modules.length; i < ln; i++) {
                        module = modules[i];

                        items = Ext.Array.from(data[module + 's']);

                        for (j = 0,subLn = items.length; j < subLn; j++) {
                            item = items[j];

                            prefix = Ext.Loader.getPrefix(item);

                            if (prefix === '' || prefix === item) {
                                requires.push(namespace + '.' + module + '.' + item);
                            }
                            else {
                                requires.push(item);
                            }
                        }
                    }

                    Ext.require(requires, Ext.Function.pass(onBeforeClassCreated, arguments, this));
                };
            }
        },

        constructor: function(config) {
            this.mixins.observable.constructor.call(this, config);

            Ext.apply(this, config || {});

            this.createGetters('model', this.models);
            this.createGetters('store', this.stores);
            this.createGetters('view', this.views);

            if (this.refs) {
                this.ref(this.refs);
            }
        },

        // Template method
        init: function(application) {},
        // Template method
        onLaunch: function(application) {},

        createGetters: function(type, refs) {
            type = Ext.String.capitalize(type);
            Ext.Array.each(refs, function(ref) {
                var fn = 'get',
                    parts = ref.split('.');

                // Handle namespaced class names. E.g. feed.Add becomes getFeedAddView etc.
                Ext.Array.each(parts, function(part) {
                    fn += Ext.String.capitalize(part);
                });
                fn += type;

                if (!this[fn]) {
                    this[fn] = Ext.Function.pass(this['get' + type], [ref], this);
                }
                // Execute it right away
                this[fn](ref);
            },
            this);
        },

        ref: function(refs) {
            var me = this;
            refs = Ext.Array.from(refs);
            Ext.Array.each(refs, function(info) {
                var ref = info.ref,
                    fn = 'get' + Ext.String.capitalize(ref);
                if (!me[fn]) {
                    me[fn] = Ext.Function.pass(me.getRef, [ref, info], me);
                }
            });
        },

        getRef: function(ref, info, config) {
            this.refCache = this.refCache || {};
            info = info || {};
            config = config || {};

            Ext.apply(info, config);

            if (info.forceCreate) {
                return Ext.ComponentManager.create(info, 'component');
            }

            var me = this,
                selector = info.selector,
                cached = me.refCache[ref];

            if (!cached) {
                me.refCache[ref] = cached = Ext.ComponentQuery.query(info.selector)[0];
                if (!cached && info.autoCreate) {
                    me.refCache[ref] = cached = Ext.ComponentManager.create(info, 'component');
                }
                if (cached) {
                    cached.on('beforedestroy', function() {
                        me.refCache[ref] = null;
                    });
                }
            }

            return cached;
        },

        control: function(selectors, listeners) {
            this.application.control(selectors, listeners, this);
        },

        getController: function(name) {
            return this.application.getController(name);
        },

        getStore: function(name) {
            return this.application.getStore(name);
        },

        getModel: function(model) {
            return this.application.getModel(model);
        },

        getView: function(view) {
            return this.application.getView(view);
        }
    });