dojo.provide("dijit._Templated");

dojo.require("dijit._Widget");
dojo.require("dojo.string");
dojo.require("dojo.parser");
dojo.require("dojo.cache");

dojo.declare("dijit._Templated",
	null,
	{
		// summary:
		//		Mixin for widgets that are instantiated from a template

		// templateString: [protected] String
		//		A string that represents the widget template. Pre-empts the
		//		templatePath. In builds that have their strings "interned", the
		//		templatePath is converted to an inline templateString, thereby
		//		preventing a synchronous network call.
		//
		//		Use in conjunction with dojo.cache() to load from a file.
		templateString: null,

		// templatePath: [protected deprecated] String
		//		Path to template (HTML file) for this widget relative to dojo.baseUrl.
		//		Deprecated: use templateString with dojo.cache() instead.
		templatePath: null,

		// widgetsInTemplate: [protected] Boolean
		//		Should we parse the template to find widgets that might be
		//		declared in markup inside it?  False by default.
		widgetsInTemplate: false,

		// skipNodeCache: [protected] Boolean
		//		If using a cached widget template node poses issues for a
		//		particular widget class, it can set this property to ensure
		//		that its template is always re-built from a string
		_skipNodeCache: false,

		// _earlyTemplatedStartup: Boolean
		//		A fallback to preserve the 1.0 - 1.3 behavior of children in
		//		templates having their startup called before the parent widget
		//		fires postCreate. Defaults to 'false', causing child widgets to
		//		have their .startup() called immediately before a parent widget
		//		.startup(), but always after the parent .postCreate(). Set to
		//		'true' to re-enable to previous, arguably broken, behavior.
		_earlyTemplatedStartup: false,

		// _attachPoints: [private] String[]
		//		List of widget attribute names associated with dojoAttachPoint=... in the
		//		template, ex: ["containerNode", "labelNode"]
/*=====
 		_attachPoints: [],
 =====*/

		constructor: function(){
			this._attachPoints = [];
		},

		_stringRepl: function(tmpl){
			// summary:
			//		Does substitution of ${foo} type properties in template string
			// tags:
			//		private
			var className = this.declaredClass, _this = this;
			// Cache contains a string because we need to do property replacement
			// do the property replacement
			return dojo.string.substitute(tmpl, this, function(value, key){
				if(key.charAt(0) == '!'){ value = dojo.getObject(key.substr(1), false, _this); }
				if(typeof value == "undefined"){ throw new Error(className+" template:"+key); } // a debugging aide
				if(value == null){ return ""; }

				// Substitution keys beginning with ! will skip the transform step,
				// in case a user wishes to insert unescaped markup, e.g. ${!foo}
				return key.charAt(0) == "!" ? value :
					// Safer substitution, see heading "Attribute values" in
					// http://www.w3.org/TR/REC-html40/appendix/notes.html#h-B.3.2
					value.toString().replace(/"/g,"&quot;"); //TODO: add &amp? use encodeXML method?
			}, this);
		},

		// method over-ride
		buildRendering: function(){
			// summary:
			//		Construct the UI for this widget from a template, setting this.domNode.
			// tags:
			//		protected

			// Lookup cached version of template, and download to cache if it
			// isn't there already.  Returns either a DomNode or a string, depending on
			// whether or not the template contains ${foo} replacement parameters.
			var cached = dijit._Templated.getCachedTemplate(this.templatePath, this.templateString, this._skipNodeCache);

			var node;
			if(dojo.isString(cached)){
				node = dojo._toDom(this._stringRepl(cached));
				if(node.nodeType != 1){
					// Flag common problems such as templates with multiple top level nodes (nodeType == 11)
					throw new Error("Invalid template: " + cached);
				}
			}else{
				// if it's a node, all we have to do is clone it
				node = cached.cloneNode(true);
			}

			this.domNode = node;

			// recurse through the node, looking for, and attaching to, our
			// attachment points and events, which should be defined on the template node.
			this._attachTemplateNodes(node);

			if(this.widgetsInTemplate){
				// Make sure dojoType is used for parsing widgets in template.
				// The dojo.parser.query could be changed from multiversion support.
				var parser = dojo.parser, qry, attr;
				if(parser._query != "[dojoType]"){
					qry = parser._query;
					attr = parser._attrName;
					parser._query = "[dojoType]";
					parser._attrName = "dojoType";
				}

				// Store widgets that we need to start at a later point in time
				var cw = (this._startupWidgets = dojo.parser.parse(node, {
					noStart: !this._earlyTemplatedStartup,
					inherited: {dir: this.dir, lang: this.lang}
				}));

				// Restore the query.
				if(qry){
					parser._query = qry;
					parser._attrName = attr;
				}

				this._supportingWidgets = dijit.findWidgets(node);

				this._attachTemplateNodes(cw, function(n,p){
					return n[p];
				});
			}

			this._fillContent(this.srcNodeRef);
		},

		_fillContent: function(/*DomNode*/ source){
			// summary:
			//		Relocate source contents to templated container node.
			//		this.containerNode must be able to receive children, or exceptions will be thrown.
			// tags:
			//		protected
			var dest = this.containerNode;
			if(source && dest){
				while(source.hasChildNodes()){
					dest.appendChild(source.firstChild);
				}
			}
		},

		_attachTemplateNodes: function(rootNode, getAttrFunc){
			// summary:
			//		Iterate through the template and attach functions and nodes accordingly.
			// description:
			//		Map widget properties and functions to the handlers specified in
			//		the dom node and it's descendants. This function iterates over all
			//		nodes and looks for these properties:
			//			* dojoAttachPoint
			//			* dojoAttachEvent
			//			* waiRole
			//			* waiState
			// rootNode: DomNode|Array[Widgets]
			//		the node to search for properties. All children will be searched.
			// getAttrFunc: Function?
			//		a function which will be used to obtain property for a given
			//		DomNode/Widget
			// tags:
			//		private

			getAttrFunc = getAttrFunc || function(n,p){ return n.getAttribute(p); };

			var nodes = dojo.isArray(rootNode) ? rootNode : (rootNode.all || rootNode.getElementsByTagName("*"));
			var x = dojo.isArray(rootNode) ? 0 : -1;
			for(; x<nodes.length; x++){
				var baseNode = (x == -1) ? rootNode : nodes[x];
				if(this.widgetsInTemplate && getAttrFunc(baseNode, "dojoType")){
					continue;
				}
				// Process dojoAttachPoint
				var attachPoint = getAttrFunc(baseNode, "dojoAttachPoint");
				if(attachPoint){
					var point, points = attachPoint.split(/\s*,\s*/);
					while((point = points.shift())){
						if(dojo.isArray(this[point])){
							this[point].push(baseNode);
						}else{
							this[point]=baseNode;
						}
						this._attachPoints.push(point);
					}
				}

				// Process dojoAttachEvent
				var attachEvent = getAttrFunc(baseNode, "dojoAttachEvent");
				if(attachEvent){
					// NOTE: we want to support attributes that have the form
					// "domEvent: nativeEvent; ..."
					var event, events = attachEvent.split(/\s*,\s*/);
					var trim = dojo.trim;
					while((event = events.shift())){
						if(event){
							var thisFunc = null;
							if(event.indexOf(":") != -1){
								// oh, if only JS had tuple assignment
								var funcNameArr = event.split(":");
								event = trim(funcNameArr[0]);
								thisFunc = trim(funcNameArr[1]);
							}else{
								event = trim(event);
							}
							if(!thisFunc){
								thisFunc = event;
							}
							this.connect(baseNode, event, thisFunc);
						}
					}
				}

				// waiRole, waiState
				var role = getAttrFunc(baseNode, "waiRole");
				if(role){
					dijit.setWaiRole(baseNode, role);
				}
				var values = getAttrFunc(baseNode, "waiState");
				if(values){
					dojo.forEach(values.split(/\s*,\s*/), function(stateValue){
						if(stateValue.indexOf('-') != -1){
							var pair = stateValue.split('-');
							dijit.setWaiState(baseNode, pair[0], pair[1]);
						}
					});
				}
			}
		},

		startup: function(){
			dojo.forEach(this._startupWidgets, function(w){
				if(w && !w._started && w.startup){
					w.startup();
				}
			});
			this.inherited(arguments);
		},

		destroyRendering: function(){
			// Delete all attach points to prevent IE6 memory leaks.
			dojo.forEach(this._attachPoints, function(point){
				delete this[point];
			}, this);
			this._attachPoints = [];

			this.inherited(arguments);
		}
	}
);

// key is either templatePath or templateString; object is either string or DOM tree
dijit._Templated._templateCache = {};

dijit._Templated.getCachedTemplate = function(templatePath, templateString, alwaysUseString){
	// summary:
	//		Static method to get a template based on the templatePath or
	//		templateString key
	// templatePath: String||dojo.uri.Uri
	//		The URL to get the template from.
	// templateString: String?
	//		a string to use in lieu of fetching the template from a URL. Takes precedence
	//		over templatePath
	// returns: Mixed
	//		Either string (if there are ${} variables that need to be replaced) or just
	//		a DOM tree (if the node can be cloned directly)

	// is it already cached?
	var tmplts = dijit._Templated._templateCache;
	var key = templateString || templatePath;
	var cached = tmplts[key];
	if(cached){
		try{
			// if the cached value is an innerHTML string (no ownerDocument) or a DOM tree created within the current document, then use the current cached value
			if(!cached.ownerDocument || cached.ownerDocument == dojo.doc){
				// string or node of the same document
				return cached;
			}
		}catch(e){ /* squelch */ } // IE can throw an exception if cached.ownerDocument was reloaded
		dojo.destroy(cached);
	}

	// If necessary, load template string from template path
	if(!templateString){
		templateString = dojo.cache(templatePath, {sanitize: true});
	}
	templateString = dojo.string.trim(templateString);

	if(alwaysUseString || templateString.match(/\$\{([^\}]+)\}/g)){
		// there are variables in the template so all we can do is cache the string
		return (tmplts[key] = templateString); //String
	}else{
		// there are no variables in the template so we can cache the DOM tree
		var node = dojo._toDom(templateString);
		if(node.nodeType != 1){
			throw new Error("Invalid template: " + templateString);
		}
		return (tmplts[key] = node); //Node
	}
};

if(dojo.isIE){
	dojo.addOnWindowUnload(function(){
		var cache = dijit._Templated._templateCache;
		for(var key in cache){
			var value = cache[key];
			if(typeof value == "object"){ // value is either a string or a DOM node template
				dojo.destroy(value);
			}
			delete cache[key];
		}
	});
}

// These arguments can be specified for widgets which are used in templates.
// Since any widget can be specified as sub widgets in template, mix it
// into the base widget class.  (This is a hack, but it's effective.)
dojo.extend(dijit._Widget,{
	dojoAttachEvent: "",
	dojoAttachPoint: "",
	waiRole: "",
	waiState:""
});
