~jstys-z/helioviewer.org/client5

/**

 * @author Patrick Schmiedel patrick.schmiedel@gmx.net

 */

 

/**

 * @classDescription Static class. Keeps a cache of retrieved urls.

 */

 

/*global Class, Control, document, $, $A, Ajax, Debug */

var AjaxRequestWrapper = Class.create();

 

AjaxRequestWrapper.cache = {};

 

/**

 * @classDescription Wraps a GET url request to contain state

 * information like the url, and simplifies the use by setting some

 * standard behaviour.

 * TODO: Create a non-cached version for retrieving data that is

 * updated frequently.

 */

AjaxRequestWrapper.getCached = Class.create();

 

AjaxRequestWrapper.getCached.prototype = {

        /**

         * @constructor                                 Creates a new instance and processes the request.

         * @param {String} url                  The url to retrieve.

         * @param {Function} callback   The function that handles the retrieved data.

         */

        initialize: function (url, callback) {

 

                // Closures

                this.url = url;

                this.callback = callback;

                

                // Get any additional arguments for XHR. The first two items of the array are

                // the url and callback function for the XHR. In many cases this.arguments will

                // simply eval to [].

                this.args = $A(arguments).slice(2);

 

                var self = this;

                

                if (AjaxRequestWrapper.cache[url]) {

                        callback.apply(null, $A([AjaxRequestWrapper.cache[self.url]]).concat(self.args));

                } else {

                        var onSuccess = function (transport) {

                                AjaxRequestWrapper.cache[self.url] = transport.responseText;

                                callback.apply(null, $A([AjaxRequestWrapper.cache[self.url]]).concat(self.args));

                        };

                        

                        var onFailure = function (transport) {

                                Debug.ajaxFailure(transport, self.url);

                        };

                        

                        var trash = new Ajax.Request(

                                url,

                                {

                                        method: 'get',

                                        onSuccess: onSuccess,

                                        onFailure: onFailure

                                }

                        );

                }

        }

};