define(["./_base/kernel", "./_base/lang", "./_base/array", "./_base/declare", "./dom", "./dom-construct", "./parser"],
	function(kernel, lang, darray, declare, dom, domConstruct, parser){
	// module:
	//		dojo/html

	// the parser might be needed..

	// idCounter is incremented with each instantiation to allow assignment of a unique id for tracking, logging purposes
	var idCounter = 0;

	var html = {
		// summary:
		//		TODOC

		_secureForInnerHtml: function(/*String*/ cont){
			// summary:
			//		removes !DOCTYPE and title elements from the html string.
			//
			//		khtml is picky about dom faults, you can't attach a style or `<title>` node as child of body
			//		must go into head, so we need to cut out those tags
			// cont:
			//		An html string for insertion into the dom
			//
			return cont.replace(/(?:\s*<!DOCTYPE\s[^>]+>|<title[^>]*>[\s\S]*?<\/title>)/ig, ""); // String
		},

		// Deprecated, should use dojo/dom-constuct.empty() directly, remove in 2.0.
		_emptyNode: domConstruct.empty,

		_setNodeContent: function(/*DomNode*/ node, /*String|DomNode|NodeList*/ cont){
			// summary:
			//		inserts the given content into the given node
			// node:
			//		the parent element
			// content:
			//		the content to be set on the parent element.
			//		This can be an html string, a node reference or a NodeList, dojo/NodeList, Array or other enumerable list of nodes

			// always empty
			domConstruct.empty(node);

			if(cont){
				if(typeof cont == "string"){
					cont = domConstruct.toDom(cont, node.ownerDocument);
				}
				if(!cont.nodeType && lang.isArrayLike(cont)){
					// handle as enumerable, but it may shrink as we enumerate it
					for(var startlen=cont.length, i=0; i<cont.length; i=startlen==cont.length ? i+1 : 0){
						domConstruct.place( cont[i], node, "last");
					}
				}else{
					// pass nodes, documentFragments and unknowns through to dojo.place
					domConstruct.place(cont, node, "last");
				}
			}

			// return DomNode
			return node;
		},

		// we wrap up the content-setting operation in a object
		_ContentSetter: declare("dojo.html._ContentSetter", null, {
			// node: DomNode|String
			//		An node which will be the parent element that we set content into
			node: "",

			// content: String|DomNode|DomNode[]
			//		The content to be placed in the node. Can be an HTML string, a node reference, or a enumerable list of nodes
			content: "",

			// id: String?
			//		Usually only used internally, and auto-generated with each instance
			id: "",

			// cleanContent: Boolean
			//		Should the content be treated as a full html document,
			//		and the real content stripped of <html>, <body> wrapper before injection
			cleanContent: false,

			// extractContent: Boolean
			//		Should the content be treated as a full html document,
			//		and the real content stripped of `<html> <body>` wrapper before injection
			extractContent: false,

			// parseContent: Boolean
			//		Should the node by passed to the parser after the new content is set
			parseContent: false,

			// parserScope: String
			//		Flag passed to parser.	Root for attribute names to search for.	  If scopeName is dojo,
			//		will search for data-dojo-type (or dojoType).  For backwards compatibility
			//		reasons defaults to dojo._scopeName (which is "dojo" except when
			//		multi-version support is used, when it will be something like dojo16, dojo20, etc.)
			parserScope: kernel._scopeName,

			// startup: Boolean
			//		Start the child widgets after parsing them.	  Only obeyed if parseContent is true.
			startup: true,

			// lifecycle methods
			constructor: function(/*Object*/ params, /*String|DomNode*/ node){
				// summary:
				//		Provides a configurable, extensible object to wrap the setting on content on a node
				//		call the set() method to actually set the content..

				// the original params are mixed directly into the instance "this"
				lang.mixin(this, params || {});

				// give precedence to params.node vs. the node argument
				// and ensure its a node, not an id string
				node = this.node = dom.byId( this.node || node );

				if(!this.id){
					this.id = [
						"Setter",
						(node) ? node.id || node.tagName : "",
						idCounter++
					].join("_");
				}
			},
			set: function(/* String|DomNode|NodeList? */ cont, /*Object?*/ params){
				// summary:
				//		front-end to the set-content sequence
				// cont:
				//		An html string, node or enumerable list of nodes for insertion into the dom
				//		If not provided, the object's content property will be used
				if(undefined !== cont){
					this.content = cont;
				}
				// in the re-use scenario, set needs to be able to mixin new configuration
				if(params){
					this._mixin(params);
				}

				this.onBegin();
				this.setContent();

				var ret = this.onEnd();

				if(ret && ret.then){
					// Make dojox/html/_ContentSetter.set() return a Promise that resolves when load and parse complete.
					return ret;
				}else{
					// Vanilla dojo/html._ContentSetter.set() returns a DOMNode for back compat.   For 2.0, switch it to
					// return a Deferred like above.
					return this.node;
				}
			},

			setContent: function(){
				// summary:
				//		sets the content on the node

				var node = this.node;
				if(!node){
					// can't proceed
					throw new Error(this.declaredClass + ": setContent given no node");
				}
				try{
					node = html._setNodeContent(node, this.content);
				}catch(e){
					// check if a domfault occurs when we are appending this.errorMessage
					// like for instance if domNode is a UL and we try append a DIV

					// FIXME: need to allow the user to provide a content error message string
					var errMess = this.onContentError(e);
					try{
						node.innerHTML = errMess;
					}catch(e){
						console.error('Fatal ' + this.declaredClass + '.setContent could not change content due to '+e.message, e);
					}
				}
				// always put back the node for the next method
				this.node = node; // DomNode
			},

			empty: function(){
				// summary:
				//		cleanly empty out existing content

				// If there is a parse in progress, cancel it.
				if(this.parseDeferred){
					if(!this.parseDeferred.isResolved()){
						this.parseDeferred.cancel();
					}
					delete this.parseDeferred;
				}

				// destroy any widgets from a previous run
				// NOTE: if you don't want this you'll need to empty
				// the parseResults array property yourself to avoid bad things happening
				if(this.parseResults && this.parseResults.length){
					darray.forEach(this.parseResults, function(w){
						if(w.destroy){
							w.destroy();
						}
					});
					delete this.parseResults;
				}
				// this is fast, but if you know its already empty or safe, you could
				// override empty to skip this step
				domConstruct.empty(this.node);
			},

			onBegin: function(){
				// summary:
				//		Called after instantiation, but before set();
				//		It allows modification of any of the object properties -
				//		including the node and content provided - before the set operation actually takes place
				//		This default implementation checks for cleanContent and extractContent flags to
				//		optionally pre-process html string content
				var cont = this.content;

				if(lang.isString(cont)){
					if(this.cleanContent){
						cont = html._secureForInnerHtml(cont);
					}

					if(this.extractContent){
						var match = cont.match(/<body[^>]*>\s*([\s\S]+)\s*<\/body>/im);
						if(match){ cont = match[1]; }
					}
				}

				// clean out the node and any cruft associated with it - like widgets
				this.empty();

				this.content = cont;
				return this.node; // DomNode
			},

			onEnd: function(){
				// summary:
				//		Called after set(), when the new content has been pushed into the node
				//		It provides an opportunity for post-processing before handing back the node to the caller
				//		This default implementation checks a parseContent flag to optionally run the dojo parser over the new content
				if(this.parseContent){
					// populates this.parseResults and this.parseDeferred if you need those..
					this._parse();
				}
				return this.node; // DomNode
				// TODO: for 2.0 return a Promise indicating that the parse completed.
			},

			tearDown: function(){
				// summary:
				//		manually reset the Setter instance if its being re-used for example for another set()
				// description:
				//		tearDown() is not called automatically.
				//		In normal use, the Setter instance properties are simply allowed to fall out of scope
				//		but the tearDown method can be called to explicitly reset this instance.
				delete this.parseResults;
				delete this.parseDeferred;
				delete this.node;
				delete this.content;
			},

			onContentError: function(err){
				return "Error occurred setting content: " + err;
			},

			onExecError: function(err){
				return "Error occurred executing scripts: " + err;
			},

			_mixin: function(params){
				// mix properties/methods into the instance
				// TODO: the intention with tearDown is to put the Setter's state
				// back to that of the original constructor (vs. deleting/resetting everything regardless of ctor params)
				// so we could do something here to move the original properties aside for later restoration
				var empty = {}, key;
				for(key in params){
					if(key in empty){ continue; }
					// TODO: here's our opportunity to mask the properties we don't consider configurable/overridable
					// .. but history shows we'll almost always guess wrong
					this[key] = params[key];
				}
			},
			_parse: function(){
				// summary:
				//		runs the dojo parser over the node contents, storing any results in this.parseResults
				//		and the parse promise in this.parseDeferred
				//		Any errors resulting from parsing are passed to _onError for handling

				var rootNode = this.node;
				try{
					// store the results (widgets, whatever) for potential retrieval
					var inherited = {};
					darray.forEach(["dir", "lang", "textDir"], function(name){
						if(this[name]){
							inherited[name] = this[name];
						}
					}, this);
					var self = this;
					this.parseDeferred = parser.parse({
						rootNode: rootNode,
						noStart: !this.startup,
						inherited: inherited,
						scope: this.parserScope
					}).then(function(results){
							return self.parseResults = results;
						}, function(e){
							self._onError('Content', e, "Error parsing in _ContentSetter#" + this.id);
						});
				}catch(e){
					this._onError('Content', e, "Error parsing in _ContentSetter#" + this.id);
				}
			},

			_onError: function(type, err, consoleText){
				// summary:
				//		shows user the string that is returned by on[type]Error
				//		override/implement on[type]Error and return your own string to customize
				var errText = this['on' + type + 'Error'].call(this, err);
				if(consoleText){
					console.error(consoleText, err);
				}else if(errText){ // a empty string won't change current content
					html._setNodeContent(this.node, errText, true);
				}
			}
		}), // end declare()

		set: function(/*DomNode*/ node, /*String|DomNode|NodeList*/ cont, /*Object?*/ params){
			// summary:
			//		inserts (replaces) the given content into the given node. dojo/dom-construct.place(cont, node, "only")
			//		may be a better choice for simple HTML insertion.
			// description:
			//		Unless you need to use the params capabilities of this method, you should use
			//		dojo/dom-construct.place(cont, node, "only"). dojo/dom-construct..place() has more robust support for injecting
			//		an HTML string into the DOM, but it only handles inserting an HTML string as DOM
			//		elements, or inserting a DOM node. dojo/dom-construct..place does not handle NodeList insertions
			//		dojo/dom-construct.place(cont, node, "only"). dojo/dom-construct.place() has more robust support for injecting
			//		an HTML string into the DOM, but it only handles inserting an HTML string as DOM
			//		elements, or inserting a DOM node. dojo/dom-construct.place does not handle NodeList insertions
			//		or the other capabilities as defined by the params object for this method.
			// node:
			//		the parent element that will receive the content
			// cont:
			//		the content to be set on the parent element.
			//		This can be an html string, a node reference or a NodeList, dojo/NodeList, Array or other enumerable list of nodes
			// params:
			//		Optional flags/properties to configure the content-setting. See dojo/html/_ContentSetter
			// example:
			//		A safe string/node/nodelist content replacement/injection with hooks for extension
			//		Example Usage:
			//	|	html.set(node, "some string");
			//	|	html.set(node, contentNode, {options});
			//	|	html.set(node, myNode.childNodes, {options});
			if(undefined == cont){
				console.warn("dojo.html.set: no cont argument provided, using empty string");
				cont = "";
			}
			if(!params){
				// simple and fast
				return html._setNodeContent(node, cont, true);
			}else{
				// more options but slower
				// note the arguments are reversed in order, to match the convention for instantiation via the parser
				var op = new html._ContentSetter(lang.mixin(
					params,
					{ content: cont, node: node }
				));
				return op.set();
			}
		}
	};
	lang.setObject("dojo.html", html);

	return html;
});
