/**
 * EGroupware eTemplate2 - JS Template base class
 *
 * @license http://opensource.org/licenses/gpl-license.php GPL - GNU General Public License
 * @package etemplate
 * @subpackage api
 * @link http://www.egroupware.org
 * @author Andreas Stöckel
 * @copyright Stylite 2011
 * @version $Id$
 */

"use strict";

/*egw:uses
	et2_core_xml;
	et2_core_DOMWidget;
*/

/**
 * Class which implements the "template" XET-Tag. When the id parameter is set,
 * the template class checks whether another template with this id already
 * exists. If yes, this template is removed from the DOM tree, copied and
 * inserted in place of this template.
 *
 * @augments et2_DOMWidget
 */
var et2_template = et2_DOMWidget.extend(
{
	attributes: {
		"template": {
			"name": "Template",
			"type": "string",
			"description": "Name / ID of template with optional cache-buster ('?'+filemtime of template on server)",
			"default": et2_no_init
		},
		"group": {
			// TODO: Not implemented
			"name": "Group",
			"description":"Not implemented",
			//"default": 0
			"default": et2_no_init
		},
		"version": {
			"name": "Version",
			"type": "string",
			"description": "Version of the template"
		},
		"lang": {
			"name": "Language",
			"type": "string",
			"description": "Language the template is written in"
		},
		"content": {
			"name": "Content index",
			"default": et2_no_init,
			"description": "Used for passing in specific content to the template other than what it would get by ID."
		}
	},

	createNamespace: true,

	/**
	 * Initializes this template widget as a simple container.
	 *
	 * @memberOf et2_template
	 * @param {et2_widget} _parent
	 * @param {object} _attrs
	 */
	init: function(_parent, _attrs) {
		// Set this early, so it's available for creating namespace
		if(_attrs.content)
		{
			this.content = _attrs.content;
		}
		this._super.apply(this, arguments);

		this.div = document.createElement("div");

		// Deferred object so we can load via AJAX
		this.loading = jQuery.Deferred();

		if (this.id != "" || this.options.template)
		{
			var parts = (this.options.template || this.id).split('?');
			var cache_buster = parts.length > 1 ? parts.pop() : null;
			var template_name = parts.pop();

			// Check to see if XML is known
			var xml = null;
			var templates = this.getRoot().getInstanceManager().templates;
			if(!(xml = templates[template_name]))
			{
				// Check to see if ID is short form --> prepend parent/top-level name
				if(template_name.indexOf('.') < 0)
				{
					var root = _parent ? _parent.getRoot() : null;
					var top_name = root && root._inst ? root._inst.name : null;
					if (top_name && template_name.indexOf('.') < 0) template_name = top_name+'.'+template_name;
				}
				xml = templates[template_name];
				if(!xml)
				{
					// Ask server
					var splitted = template_name.split('.');
					var path = this.egw().webserverUrl + "/" + splitted.shift() + "/templates/default/" +
						splitted.join('.')+ ".xet" + (cache_buster ? '?'+cache_buster : '');

					if(splitted.length)
					{
						et2_loadXMLFromURL(path, function(_xmldoc) {
							var templates = this.getInstanceManager().templates || {};
							// Scan for templates and store them
							for(var i = 0; i < _xmldoc.childNodes.length; i++) {
								var template = _xmldoc.childNodes[i];
								if(template.nodeName.toLowerCase() != "template") continue;
								templates[template.getAttribute("id")] = template;
							}

							// Read the XML structure of the requested template
							this.loadFromXML(templates[template_name]);

							// Update flag
							this.loading.resolve();

						}, this);
					}
					return;
				}
			}
			if(xml !== null && typeof xml !== "undefined")
			{
				this.egw().debug("log", "Loading template from XML: ", template_name);
				this.loadFromXML(xml);
				// Don't call this here - done by caller, or on whole widget tree
				//this.loadingFinished();

				// But resolve the promise
				this.loading.resolve();
			}
			else
			{
				this.egw().debug("warn", "Unable to find XML for ", template_name);
				this.loading.reject();
			}
		}
		else
		{
			// No actual template
			this.loading.resolve();
		}
	},

	/**
	 * Override parent to support content attribute
	 * Templates always have ID set, but seldom do we want them to
	 * create a namespace based on their ID.
	 */
	checkCreateNamespace: function() {
		if(this.content)
		{
			var old_id = this.id;
			this.id = this.content;
			this._super.apply(this, arguments);
			this.id = old_id;
		}
	},

	getDOMNode: function() {
		return this.div;
	},

	/**
	 * Override to return the promise for deferred loading
	 */
	doLoadingFinished: function() {
		// Apply parent now, which actually puts into the DOM
		this._super.apply(this, arguments);

		// Fire load event when done loading
		this.loading.done(jQuery.proxy(function() {$j(this).trigger("load");},this.div));

		// Not done yet, but widget will let you know
		return this.loading.promise();
	}
});
et2_register_widget(et2_template, ["template"]);