/*
Script: Browser.js
	The Browser Core. Contains Browser initialization, Window and Document, and the Browser Hash.

License:
	MIT-style license.
*/

var Browser = new Hash({
	Engine: {'name': 'unknown', 'version': ''},
	Platform: {'name': (navigator.platform.match(/mac|win|linux|nix/i) || ['other'])[0].toLowerCase()}, 
	Features: {'xhr': !!(window.XMLHttpRequest), 'xpath': !!(document.evaluate)}
});

if (window.opera) Browser.Engine.name = 'presto';
else if (window.ActiveXObject) Browser.Engine = {'name': 'trident', 'version': (Browser.Features.xhr) ? 5 : 4};
else if (!navigator.taintEnabled) Browser.Engine = {'name': 'webkit', 'version': (Browser.Features.xpath) ? 420 : 419};
else if (document.getBoxObjectFor != null) Browser.Engine.name = 'gecko';
Browser.Engine[Browser.Engine.name] = Browser.Engine[Browser.Engine.name + Browser.Engine.version] = true;
Browser.Platform[Browser.Platform.name] = true;

function $exec(text){
	if (!text) return text;
	if (window.execScript){
		window.execScript(text);
	} else {
		var script = document.createElement('script');
		script.setAttribute('type', 'text/javascript');
		script.text = text;
		document.head.appendChild(script);
		document.head.removeChild(script);
	}
	return text;
};

Native.UID = 0;

var Window = new Native({

	name: 'Window',

	legacy: window.Window,

	initialize: function(win){
		if (!win.Element){
			win.Element = $empty;
			if (Browser.Engine.webkit) win.document.createElement("iframe"); //fixes safari 2
			win.Element.prototype = (Browser.Engine.webkit) ? window["[[DOMElement.prototype]]"] : {};
		}
		win.uid = Native.UID++;
		return $extend(win, Window.Prototype);
	},

	afterImplement: function(property, value){
		window[property] = Window.Prototype[property] = value;
	}

});

Window.Prototype = {$family: {name: 'window'}};

new Window(window);

var Document = new Native({

	name: 'Document',

	legacy: window.Document,

	initialize: function(doc){
		doc.head = doc.getElementsByTagName('head')[0];
		doc.html = doc.getElementsByTagName('html')[0];
		doc.window = doc.defaultView || doc.parentWindow;
		if (Browser.Engine.trident4) $try(function(){
			doc.execCommand("BackgroundImageCache", false, true);
		});
		doc.uid = Native.UID++;
		return $extend(doc, Document.Prototype);
	},

	afterImplement: function(property, value){
		document[property] = Document.Prototype[property] = value;
	}

});

Document.Prototype = {$family: {name: 'document'}};

new Document(document);