var popupWindow = function() {
	function getWindowSize() {
		var w = 0, h = 0;
		if (typeof(window.innerWidth) == 'number') {
			w = window.innerWidth;
			h = window.innerHeight;
		} else if (document.documentElement
				&& (document.documentElement.clientWidth || document.documentElement.clientHeight)) {
			w = document.documentElement.clientWidth;
			h = document.documentElement.clientHeight;
		} else if (document.body
				&& (document.body.clientWidth || document.body.clientHeight)) {
			w = document.body.clientWidth;
			h = document.body.clientHeight;
		}
		
		return {width: w - 50, height: h - 50};
	}
	
	function loadStyle(css) {
		var cssEl = document.createElement('link');
		cssEl.setAttribute('href', css);
		cssEl.setAttribute('rel', 'stylesheet');
		cssEl.setAttribute('type', 'text/css');
		document.getElementsByTagName('head')[0].appendChild(cssEl);
	}
	
	function loadScript(script) {
		var scriptEl = document.createElement('script');
		scriptEl.setAttribute('src', script);
		scriptEl.setAttribute('type', 'text/javascript');
		document.getElementsByTagName('head')[0].appendChild(scriptEl);
	}
	
	function doWindowOpen(url, title, width, height) {
		if (width == null) width = 450;
		if (height == null) height = 300;
		
		var windowSize = getWindowSize();
		if (width > windowSize.width) width = windowSize.width;
		if (height > windowSize.height) height = windowSize.height;
		
		var win = new Ext.Window({
			modal: true,
			width: width,
			height: height,
			contentEl: Ext.DomHelper.append(Ext.getBody(), {
				tag: 'iframe', src: url, frameborder: 0, width: "100%", height: "100%"
			})
		});
		win.show();
	}
	
	return {
		open: function(url, title, width, height) {
			var lazyLoading = false;
			
			if (! window.Ext) {
				loadStyle("/util/ext-3.0.0-window/css/ext-all.css");
				loadScript("/util/ext-3.0.0-window/win.js");
				lazyLoading = true;
			}
			
			if (lazyLoading) {
				var openArgs = arguments;
				var func = function() {
					if (! window.Ext || ! window.Ext.Window) { 
						setTimeout(func, 100);
					} else {
						doWindowOpen.apply(this, openArgs);
					}
				}
				setTimeout(func, 100);
			} else {
				doWindowOpen.apply(this, arguments);
			}
		}
	}
}();