/**
 * @class Ext.Updater
 * @extends Ext.util.Observable
 * Provides AJAX-style update capabilities for Element objects.  Updater can be used to {@link #update}
 * an {@link Ext.Element} once, or you can use {@link #startAutoRefresh} to set up an auto-updating
 * {@link Ext.Element Element} on a specific interval.<br><br>
 * Usage:<br>
 * <pre><code>
 * var el = Ext.get("foo"); // Get Ext.Element object
 * var mgr = el.getUpdater();
 * mgr.update({
        url: "http://myserver.com/index.php",
        params: {
            param1: "foo",
            param2: "bar"
        }
 * });
 * ...
 * mgr.formUpdate("myFormId", "http://myserver.com/index.php");
 * <br>
 * // or directly (returns the same Updater instance)
 * var mgr = new Ext.Updater("myElementId");
 * mgr.startAutoRefresh(60, "http://myserver.com/index.php");
 * mgr.on("update", myFcnNeedsToKnow);
 * <br>
 * // short handed call directly from the element object
 * Ext.get("foo").load({
        url: "bar.php",
        scripts: true,
        params: "param1=foo&amp;param2=bar",
        text: "Loading Foo..."
 * });
 * </code></pre>
 * @constructor
 * Create new Updater directly.
 * @param {Mixed} el The element to update
 * @param {Boolean} forceNew (optional) By default the constructor checks to see if the passed element already
 * has an Updater and if it does it returns the same instance. This will skip that check (useful for extending this class).
 */
Ext.UpdateManager = Ext.Updater = Ext.extend(Ext.util.Observable,
function() {
    var BEFOREUPDATE = "beforeupdate",
        UPDATE = "update",
        FAILURE = "failure";

    // private
    function processSuccess(response){
        var me = this;
        me.transaction = null;
        if (response.argument.form && response.argument.reset) {
            try { // put in try/catch since some older FF releases had problems with this
                response.argument.form.reset();
            } catch(e){}
        }
        if (me.loadScripts) {
            me.renderer.render(me.el, response, me,
               updateComplete.createDelegate(me, [response]));
        } else {
            me.renderer.render(me.el, response, me);
            updateComplete.call(me, response);
        }
    }

    // private
    function updateComplete(response, type, success){
        this.fireEvent(type || UPDATE, this.el, response);
        if(Ext.isFunction(response.argument.callback)){
            response.argument.callback.call(response.argument.scope, this.el, Ext.isEmpty(success) ? true : false, response, response.argument.options);
        }
    }

    // private
    function processFailure(response){
        updateComplete.call(this, response, FAILURE, !!(this.transaction = null));
    }

    return {
        constructor: function(el, forceNew){
            var me = this;
            el = Ext.get(el);
            if(!forceNew && el.updateManager){
                return el.updateManager;
            }
            /**
             * The Element object
             * @type Ext.Element
             */
            me.el = el;
            /**
             * Cached url to use for refreshes. Overwritten every time update() is called unless "discardUrl" param is set to true.
             * @type String
             */
            me.defaultUrl = null;

            me.addEvents(
                /**
                 * @event beforeupdate
                 * Fired before an update is made, return false from your handler and the update is cancelled.
                 * @param {Ext.Element} el
                 * @param {String/Object/Function} url
                 * @param {String/Object} params
                 */
                BEFOREUPDATE,
                /**
                 * @event update
                 * Fired after successful update is made.
                 * @param {Ext.Element} el
                 * @param {Object} oResponseObject The response Object
                 */
                UPDATE,
                /**
                 * @event failure
                 * Fired on update failure.
                 * @param {Ext.Element} el
                 * @param {Object} oResponseObject The response Object
                 */
                FAILURE
            );

            Ext.apply(me, Ext.Updater.defaults);
            /**
             * Blank page URL to use with SSL file uploads (defaults to {@link Ext.Updater.defaults#sslBlankUrl}).
             * @property sslBlankUrl
             * @type String
             */
            /**
             * Whether to append unique parameter on get request to disable caching (defaults to {@link Ext.Updater.defaults#disableCaching}).
             * @property disableCaching
             * @type Boolean
             */
            /**
             * Text for loading indicator (defaults to {@link Ext.Updater.defaults#indicatorText}).
             * @property indicatorText
             * @type String
             */
            /**
             * Whether to show indicatorText when loading (defaults to {@link Ext.Updater.defaults#showLoadIndicator}).
             * @property showLoadIndicator
             * @type String
             */
            /**
             * Timeout for requests or form posts in seconds (defaults to {@link Ext.Updater.defaults#timeout}).
             * @property timeout
             * @type Number
             */
            /**
             * True to process scripts in the output (defaults to {@link Ext.Updater.defaults#loadScripts}).
             * @property loadScripts
             * @type Boolean
             */

            /**
             * Transaction object of the current executing transaction, or null if there is no active transaction.
             */
            me.transaction = null;
            /**
             * Delegate for refresh() prebound to "this", use myUpdater.refreshDelegate.createCallback(arg1, arg2) to bind arguments
             * @type Function
             */
            me.refreshDelegate = me.refresh.createDelegate(me);
            /**
             * Delegate for update() prebound to "this", use myUpdater.updateDelegate.createCallback(arg1, arg2) to bind arguments
             * @type Function
             */
            me.updateDelegate = me.update.createDelegate(me);
            /**
             * Delegate for formUpdate() prebound to "this", use myUpdater.formUpdateDelegate.createCallback(arg1, arg2) to bind arguments
             * @type Function
             */
            me.formUpdateDelegate = (me.formUpdate || function(){}).createDelegate(me);

            /**
             * The renderer for this Updater (defaults to {@link Ext.Updater.BasicRenderer}).
             */
            me.renderer = me.renderer || me.getDefaultRenderer();

            Ext.Updater.superclass.constructor.call(me);
        },

        /**
         * Sets the content renderer for this Updater. See {@link Ext.Updater.BasicRenderer#render} for more details.
         * @param {Object} renderer The object implementing the render() method
         */
        setRenderer : function(renderer){
            this.renderer = renderer;
        },

        /**
         * Returns the current content renderer for this Updater. See {@link Ext.Updater.BasicRenderer#render} for more details.
         * @return {Object}
         */
        getRenderer : function(){
           return this.renderer;
        },

        /**
         * This is an overrideable method which returns a reference to a default
         * renderer class if none is specified when creating the Ext.Updater.
         * Defaults to {@link Ext.Updater.BasicRenderer}
         */
        getDefaultRenderer: function() {
            return new Ext.Updater.BasicRenderer();
        },

        /**
         * Sets the default URL used for updates.
         * @param {String/Function} defaultUrl The url or a function to call to get the url
         */
        setDefaultUrl : function(defaultUrl){
            this.defaultUrl = defaultUrl;
        },

        /**
         * Get the Element this Updater is bound to
         * @return {Ext.Element} The element
         */
        getEl : function(){
            return this.el;
        },

        /**
         * Performs an <b>asynchronous</b> request, updating this element with the response.
         * If params are specified it uses POST, otherwise it uses GET.<br><br>
         * <b>Note:</b> Due to the asynchronous nature of remote server requests, the Element
         * will not have been fully updated when the function returns. To post-process the returned
         * data, use the callback option, or an <b><code>update</code></b> event handler.
         * @param {Object} options A config object containing any of the following options:<ul>
         * <li>url : <b>String/Function</b><p class="sub-desc">The URL to request or a function which
         * <i>returns</i> the URL (defaults to the value of {@link Ext.Ajax#url} if not specified).</p></li>
         * <li>method : <b>String</b><p class="sub-desc">The HTTP method to
         * use. Defaults to POST if the <code>params</code> argument is present, otherwise GET.</p></li>
         * <li>params : <b>String/Object/Function</b><p class="sub-desc">The
         * parameters to pass to the server (defaults to none). These may be specified as a url-encoded
         * string, or as an object containing properties which represent parameters,
         * or as a function, which returns such an object.</p></li>
         * <li>scripts : <b>Boolean</b><p class="sub-desc">If <code>true</code>
         * any &lt;script&gt; tags embedded in the response text will be extracted
         * and executed (defaults to {@link Ext.Updater.defaults#loadScripts}). If this option is specified,
         * the callback will be called <i>after</i> the execution of the scripts.</p></li>
         * <li>callback : <b>Function</b><p class="sub-desc">A function to
         * be called when the response from the server arrives. The following
         * parameters are passed:<ul>
         * <li><b>el</b> : Ext.Element<p class="sub-desc">The Element being updated.</p></li>
         * <li><b>success</b> : Boolean<p class="sub-desc">True for success, false for failure.</p></li>
         * <li><b>response</b> : XMLHttpRequest<p class="sub-desc">The XMLHttpRequest which processed the update.</p></li>
         * <li><b>options</b> : Object<p class="sub-desc">The config object passed to the update call.</p></li></ul>
         * </p></li>
         * <li>scope : <b>Object</b><p class="sub-desc">The scope in which
         * to execute the callback (The callback's <code>this</code> reference.) If the
         * <code>params</code> argument is a function, this scope is used for that function also.</p></li>
         * <li>discardUrl : <b>Boolean</b><p class="sub-desc">By default, the URL of this request becomes
         * the default URL for this Updater object, and will be subsequently used in {@link #refresh}
         * calls.  To bypass this behavior, pass <code>discardUrl:true</code> (defaults to false).</p></li>
         * <li>timeout : <b>Number</b><p class="sub-desc">The number of seconds to wait for a response before
         * timing out (defaults to {@link Ext.Updater.defaults#timeout}).</p></li>
         * <li>text : <b>String</b><p class="sub-desc">The text to use as the innerHTML of the
         * {@link Ext.Updater.defaults#indicatorText} div (defaults to 'Loading...').  To replace the entire div, not
         * just the text, override {@link Ext.Updater.defaults#indicatorText} directly.</p></li>
         * <li>nocache : <b>Boolean</b><p class="sub-desc">Only needed for GET
         * requests, this option causes an extra, auto-generated parameter to be appended to the request
         * to defeat caching (defaults to {@link Ext.Updater.defaults#disableCaching}).</p></li></ul>
         * <p>
         * For example:
    <pre><code>
    um.update({
        url: "your-url.php",
        params: {param1: "foo", param2: "bar"}, // or a URL encoded string
        callback: yourFunction,
        scope: yourObject, //(optional scope)
        discardUrl: true,
        nocache: true,
        text: "Loading...",
        timeout: 60,
        scripts: false // Save time by avoiding RegExp execution.
    });
    </code></pre>
         */
        update : function(url, params, callback, discardUrl){
            var me = this,
                cfg,
                callerScope;

            if(me.fireEvent(BEFOREUPDATE, me.el, url, params) !== false){
                if(Ext.isObject(url)){ // must be config object
                    cfg = url;
                    url = cfg.url;
                    params = params || cfg.params;
                    callback = callback || cfg.callback;
                    discardUrl = discardUrl || cfg.discardUrl;
                    callerScope = cfg.scope;
                    if(!Ext.isEmpty(cfg.nocache)){me.disableCaching = cfg.nocache;};
                    if(!Ext.isEmpty(cfg.text)){me.indicatorText = '<div class="loading-indicator">'+cfg.text+"</div>";};
                    if(!Ext.isEmpty(cfg.scripts)){me.loadScripts = cfg.scripts;};
                    if(!Ext.isEmpty(cfg.timeout)){me.timeout = cfg.timeout;};
                }
                me.showLoading();

                if(!discardUrl){
                    me.defaultUrl = url;
                }
                if(Ext.isFunction(url)){
                    url = url.call(me);
                }

                var o = Ext.apply({}, {
                    url : url,
                    params: (Ext.isFunction(params) && callerScope) ? params.createDelegate(callerScope) : params,
                    success: processSuccess,
                    failure: processFailure,
                    scope: me,
                    callback: undefined,
                    timeout: (me.timeout*1000),
                    disableCaching: me.disableCaching,
                    argument: {
                        "options": cfg,
                        "url": url,
                        "form": null,
                        "callback": callback,
                        "scope": callerScope || window,
                        "params": params
                    }
                }, cfg);

                me.transaction = Ext.Ajax.request(o);
            }
        },

        /**
         * <p>Performs an asynchronous form post, updating this element with the response. If the form has the attribute
         * enctype="<a href="http://www.faqs.org/rfcs/rfc2388.html">multipart/form-data</a>", it assumes it's a file upload.
         * Uses this.sslBlankUrl for SSL file uploads to prevent IE security warning.</p>
         * <p>File uploads are not performed using normal "Ajax" techniques, that is they are <b>not</b>
         * performed using XMLHttpRequests. Instead the form is submitted in the standard manner with the
         * DOM <code>&lt;form></code> element temporarily modified to have its
         * <a href="http://www.w3.org/TR/REC-html40/present/frames.html#adef-target">target</a> set to refer
         * to a dynamically generated, hidden <code>&lt;iframe></code> which is inserted into the document
         * but removed after the return data has been gathered.</p>
         * <p>Be aware that file upload packets, sent with the content type <a href="http://www.faqs.org/rfcs/rfc2388.html">multipart/form-data</a>
         * and some server technologies (notably JEE) may require some custom processing in order to
         * retrieve parameter names and parameter values from the packet content.</p>
         * @param {String/HTMLElement} form The form Id or form element
         * @param {String} url (optional) The url to pass the form to. If omitted the action attribute on the form will be used.
         * @param {Boolean} reset (optional) Whether to try to reset the form after the update
         * @param {Function} callback (optional) Callback when transaction is complete. The following
         * parameters are passed:<ul>
         * <li><b>el</b> : Ext.Element<p class="sub-desc">The Element being updated.</p></li>
         * <li><b>success</b> : Boolean<p class="sub-desc">True for success, false for failure.</p></li>
         * <li><b>response</b> : XMLHttpRequest<p class="sub-desc">The XMLHttpRequest which processed the update.</p></li></ul>
         */
        formUpdate : function(form, url, reset, callback){
            var me = this;
            if(me.fireEvent(BEFOREUPDATE, me.el, form, url) !== false){
                if(Ext.isFunction(url)){
                    url = url.call(me);
                }
                form = Ext.getDom(form);
                me.transaction = Ext.Ajax.request({
                    form: form,
                    url:url,
                    success: processSuccess,
                    failure: processFailure,
                    scope: me,
                    timeout: (me.timeout*1000),
                    argument: {
                        "url": url,
                        "form": form,
                        "callback": callback,
                        "reset": reset
                    }
                });
                me.showLoading.defer(1, me);
            }
        },

        /**
         * Set this element to auto refresh.  Can be canceled by calling {@link #stopAutoRefresh}.
         * @param {Number} interval How often to update (in seconds).
         * @param {String/Object/Function} url (optional) The url for this request, a config object in the same format
         * supported by {@link #load}, or a function to call to get the url (defaults to the last used url).  Note that while
         * the url used in a load call can be reused by this method, other load config options will not be reused and must be
         * sepcified as part of a config object passed as this paramter if needed.
         * @param {String/Object} params (optional) The parameters to pass as either a url encoded string
         * "&param1=1&param2=2" or as an object {param1: 1, param2: 2}
         * @param {Function} callback (optional) Callback when transaction is complete - called with signature (oElement, bSuccess)
         * @param {Boolean} refreshNow (optional) Whether to execute the refresh now, or wait the interval
         */
        startAutoRefresh : function(interval, url, params, callback, refreshNow){
            var me = this;
            if(refreshNow){
                me.update(url || me.defaultUrl, params, callback, true);
            }
            if(me.autoRefreshProcId){
                clearInterval(me.autoRefreshProcId);
            }
            me.autoRefreshProcId = setInterval(me.update.createDelegate(me, [url || me.defaultUrl, params, callback, true]), interval * 1000);
        },

        /**
         * Stop auto refresh on this element.
         */
        stopAutoRefresh : function(){
            if(this.autoRefreshProcId){
                clearInterval(this.autoRefreshProcId);
                delete this.autoRefreshProcId;
            }
        },

        /**
         * Returns true if the Updater is currently set to auto refresh its content (see {@link #startAutoRefresh}), otherwise false.
         */
        isAutoRefreshing : function(){
           return !!this.autoRefreshProcId;
        },

        /**
         * Display the element's "loading" state. By default, the element is updated with {@link #indicatorText}. This
         * method may be overridden to perform a custom action while this Updater is actively updating its contents.
         */
        showLoading : function(){
            if(this.showLoadIndicator){
                this.el.dom.innerHTML = this.indicatorText;
            }
        },

        /**
         * Aborts the currently executing transaction, if any.
         */
        abort : function(){
            if(this.transaction){
                Ext.Ajax.abort(this.transaction);
            }
        },

        /**
         * Returns true if an update is in progress, otherwise false.
         * @return {Boolean}
         */
        isUpdating : function(){
            return this.transaction ? Ext.Ajax.isLoading(this.transaction) : false;
        },

        /**
         * Refresh the element with the last used url or defaultUrl. If there is no url, it returns immediately
         * @param {Function} callback (optional) Callback when transaction is complete - called with signature (oElement, bSuccess)
         */
        refresh : function(callback){
            if(this.defaultUrl){
                this.update(this.defaultUrl, null, callback, true);
            }
        }
    };
}());

/**
 * @class Ext.Updater.defaults
 * The defaults collection enables customizing the default properties of Updater
 */
Ext.Updater.defaults = {
   /**
     * Timeout for requests or form posts in seconds (defaults to 30 seconds).
     * @type Number
     */
    timeout : 30,
    /**
     * True to append a unique parameter to GET requests to disable caching (defaults to false).
     * @type Boolean
     */
    disableCaching : false,
    /**
     * Whether or not to show {@link #indicatorText} during loading (defaults to true).
     * @type Boolean
     */
    showLoadIndicator : true,
    /**
     * Text for loading indicator (defaults to '&lt;div class="loading-indicator"&gt;Loading...&lt;/div&gt;').
     * @type String
     */
    indicatorText : '<div class="loading-indicator">Loading...</div>',
     /**
     * True to process scripts by default (defaults to false).
     * @type Boolean
     */
    loadScripts : false,
    /**
    * Blank page URL to use with SSL file uploads (defaults to {@link Ext#SSL_SECURE_URL} if set, or "javascript:false").
    * @type String
    */
    sslBlankUrl : Ext.SSL_SECURE_URL
};


/**
 * Static convenience method. <b>This method is deprecated in favor of el.load({url:'foo.php', ...})</b>.
 * Usage:
 * <pre><code>Ext.Updater.updateElement("my-div", "stuff.php");</code></pre>
 * @param {Mixed} el The element to update
 * @param {String} url The url
 * @param {String/Object} params (optional) Url encoded param string or an object of name/value pairs
 * @param {Object} options (optional) A config object with any of the Updater properties you want to set - for
 * example: {disableCaching:true, indicatorText: "Loading data..."}
 * @static
 * @deprecated
 * @member Ext.Updater
 */
Ext.Updater.updateElement = function(el, url, params, options){
    var um = Ext.get(el).getUpdater();
    Ext.apply(um, options);
    um.update(url, params, options ? options.callback : null);
};

/**
 * @class Ext.Updater.BasicRenderer
 * <p>This class is a base class implementing a simple render method which updates an element using results from an Ajax request.</p>
 * <p>The BasicRenderer updates the element's innerHTML with the responseText. To perform a custom render (i.e. XML or JSON processing),
 * create an object with a conforming {@link #render} method and pass it to setRenderer on the Updater.</p>
 */
Ext.Updater.BasicRenderer = function(){};

Ext.Updater.BasicRenderer.prototype = {
    /**
     * This method is called when an Ajax response is received, and an Element needs updating.
     * @param {Ext.Element} el The element being rendered
     * @param {Object} xhr The XMLHttpRequest object
     * @param {Updater} updateManager The calling update manager
     * @param {Function} callback A callback that will need to be called if loadScripts is true on the Updater
     */
     render : function(el, response, updateManager, callback){
        el.update(response.responseText, updateManager.loadScripts, callback);
    }
};