    /**
     * Provides a registry of available Plugin classes indexed by a mnemonic code known as the Plugin's ptype.
     *
     * A plugin may be specified simply as a *config object* as long as the correct `ptype` is specified:
     *
     *     {
     *         ptype: 'gridviewdragdrop',
     *         dragText: 'Drag and drop to reorganize'
     *     }
     *
     * Or just use the ptype on its own:
     *
     *     'gridviewdragdrop'
     *
     * Alternatively you can instantiate the plugin with Ext.create:
     *
     *     Ext.create('Ext.grid.plugin.DragDrop', {
     *         dragText: 'Drag and drop to reorganize'
     *     })
     */
    Ext.define('Ext.PluginManager', {
        extend: 'Ext.AbstractManager',
        alternateClassName: 'Ext.PluginMgr',
        singleton: true,
        typeName: 'ptype',

        /**
         * Creates a new Plugin from the specified config object using the config object's ptype to determine the class to
         * instantiate.
         * @param {Object} config A configuration object for the Plugin you wish to create.
         * @param {Function} defaultType (optional) The constructor to provide the default Plugin type if the config object does not
         * contain a `ptype`. (Optional if the config contains a `ptype`).
         * @return {Ext.Component} The newly instantiated Plugin.
         */
        create : function(config, defaultType){
            if (config.init) {
                return config;
            } else {
                return Ext.createByAlias('plugin.' + (config.ptype || defaultType), config);
            }

            // Prior system supported Singleton plugins.
            //var PluginCls = this.types[config.ptype || defaultType];
            //if (PluginCls.init) {
            //    return PluginCls;
            //} else {
            //    return new PluginCls(config);
            //}
        },

        //create: function(plugin, defaultType) {
        //    if (plugin instanceof this) {
        //        return plugin;
        //    } else {
        //        var type, config = {};
        //
        //        if (Ext.isString(plugin)) {
        //            type = plugin;
        //        }
        //        else {
        //            type = plugin[this.typeName] || defaultType;
        //            config = plugin;
        //        }
        //
        //        return Ext.createByAlias('plugin.' + type, config);
        //    }
        //},

        /**
         * Returns all plugins registered with the given type. Here, 'type' refers to the type of plugin, not its ptype.
         * @param {String} type The type to search for
         * @param {Boolean} defaultsOnly True to only return plugins of this type where the plugin's isDefault property is
         * truthy
         * @return {Ext.AbstractPlugin[]} All matching plugins
         */
        findByType: function(type, defaultsOnly) {
            var matches = [],
                types   = this.types,
                name,
                item;

            for (name in types) {
                if (!types.hasOwnProperty(name)) {
                    continue;
                }
                item = types[name];

                if (item.type == type && (!defaultsOnly || (defaultsOnly === true && item.isDefault))) {
                    matches.push(item);
                }
            }

            return matches;
        }
    }, function() {
        /**
         * Shorthand for {@link Ext.PluginManager#registerType}
         * @param {String} ptype The ptype mnemonic string by which the Plugin class
         * may be looked up.
         * @param {Function} cls The new Plugin class.
         * @member Ext
         * @method preg
         */
        Ext.preg = function() {
            return Ext.PluginManager.registerType.apply(Ext.PluginManager, arguments);
        };
    });