YUI.add('datasource-cache', function (Y, NAME) {

/**

 * Plugs DataSource with caching functionality.

 *

 * @module datasource

 * @submodule datasource-cache

 */

/**

 * DataSourceCache extension binds Cache to DataSource.

 * @class DataSourceCacheExtension

 */

var DataSourceCacheExtension = function() {

};

Y.mix(DataSourceCacheExtension, {

    /**

     * The namespace for the plugin. This will be the property on the host which

     * references the plugin instance.

     *

     * @property NS

     * @type String

     * @static

     * @final

     * @value "cache"

     */

    NS: "cache",

    /**

     * Class name.

     *

     * @property NAME

     * @type String

     * @static

     * @final

     * @value "dataSourceCacheExtension"

     */

    NAME: "dataSourceCacheExtension"

});

DataSourceCacheExtension.prototype = {

    /**

    * Internal init() handler.

    *

    * @method initializer

    * @param config {Object} Config object.

    * @private

    */

    initializer: function(config) {

        this.doBefore("_defRequestFn", this._beforeDefRequestFn);

        this.doBefore("_defResponseFn", this._beforeDefResponseFn);

    },

    /**

     * First look for cached response, then send request to live data.

     *

     * @method _beforeDefRequestFn

     * @param e {EventFacade} Event Facade with the following properties:

     * <dl>

     * <dt>tId (Number)</dt> <dd>Unique transaction ID.</dd>

     * <dt>request (Object)</dt> <dd>The request.</dd>

     * <dt>callback (Object)</dt> <dd>The callback object.</dd>

     * <dt>cfg (Object)</dt> <dd>Configuration object.</dd>

     * </dl>

     * @protected

     */

    _beforeDefRequestFn: function(e) {

        // Is response already in the Cache?

        var entry = (this.retrieve(e.request)) || null,

            payload = e.details[0];

        if (entry && entry.response) {

            payload.cached   = entry.cached;

            payload.response = entry.response;

            payload.data     = entry.data;

            this.get("host").fire("response", payload);

            return new Y.Do.Halt("DataSourceCache extension halted _defRequestFn");

        }

    },

    /**

     * Adds data to cache before returning data.

     *

     * @method _beforeDefResponseFn

     * @param e {EventFacade} Event Facade with the following properties:

     * <dl>

     * <dt>tId (Number)</dt> <dd>Unique transaction ID.</dd>

     * <dt>request (Object)</dt> <dd>The request.</dd>

     * <dt>callback (Object)</dt> <dd>The callback object with the following properties:

     *     <dl>

     *         <dt>success (Function)</dt> <dd>Success handler.</dd>

     *         <dt>failure (Function)</dt> <dd>Failure handler.</dd>

     *     </dl>

     * </dd>

     * <dt>data (Object)</dt> <dd>Raw data.</dd>

     * <dt>response (Object)</dt> <dd>Normalized response object with the following properties:

     *     <dl>

     *         <dt>cached (Object)</dt> <dd>True when response is cached.</dd>

     *         <dt>results (Object)</dt> <dd>Parsed results.</dd>

     *         <dt>meta (Object)</dt> <dd>Parsed meta data.</dd>

     *         <dt>error (Object)</dt> <dd>Error object.</dd>

     *     </dl>

     * </dd>

     * <dt>cfg (Object)</dt> <dd>Configuration object.</dd>

     * </dl>

     * @protected

     */

     _beforeDefResponseFn: function(e) {

        // Add to Cache before returning

        if(e.response && !e.cached) {

            this.add(e.request, e.response);

        }

     }

};

Y.namespace("Plugin").DataSourceCacheExtension = DataSourceCacheExtension;

/**

 * DataSource plugin adds cache functionality.

 * @class DataSourceCache

 * @extends Cache

 * @uses Plugin.Base, DataSourceCachePlugin

 */

function DataSourceCache(config) {

    var cache = config && config.cache ? config.cache : Y.Cache,

        tmpclass = Y.Base.create("dataSourceCache", cache, [Y.Plugin.Base, Y.Plugin.DataSourceCacheExtension]),

        tmpinstance = new tmpclass(config);

    tmpclass.NS = "tmpClass";

    return tmpinstance;

}

Y.mix(DataSourceCache, {

    /**

     * The namespace for the plugin. This will be the property on the host which

     * references the plugin instance.

     *

     * @property NS

     * @type String

     * @static

     * @final

     * @value "cache"

     */

    NS: "cache",

    /**

     * Class name.

     *

     * @property NAME

     * @type String

     * @static

     * @final

     * @value "dataSourceCache"

     */

    NAME: "dataSourceCache"

});

Y.namespace("Plugin").DataSourceCache = DataSourceCache;

}, '@VERSION@', {"requires": ["datasource-local", "plugin", "cache-base"]});