// dhtml popup

var eckPopup = {
	
	popup_responseAHAH: function(pageElement, req)
	{
		var output = '';
		
		if(req.readyState == 4) {
			if(req.status == 200)
			{
				//alert(pageElement); debug
				output = req.responseText;
				document.getElementById(pageElement).innerHTML = output;
			}
			if(req.status == 500)
			{
				//alert(pageElement); debug
				output = req.responseText;
				document.getElementById(pageElement).innerHTML = output;
			}
			if(req.status == 404)
			{
				//alert(pageElement); debug
				output = "404 not found";
				document.getElementById(pageElement).innerHTML = output;
			}
		}
	},
	
	popup_callAHAH: function(url, pageElement, callMessage)
	{
		var req; // we have multiple instances at the same time
		
		document.getElementById(pageElement).innerHTML = callMessage;
		
		try {
			req = new XMLHttpRequest();	/* fire fox */
		} catch(e) {
			try { 
				req = new ActiveXObject("Msxml2.XMLHTTP"); /* some versions of IE */
			} catch(e){
				try {
					req = new ActiveXObject("Microsoft.XMLHTTP"); /* other versions of IE */
				} catch(e) {
					req = false;
				}
			}
		}
		// test to see it xmlHttp has been created
		if (req==null)
		{
			alert ("Your browser does not support AJAX!");
			return;
		} 
		req.onreadystatechange = function(){
			eckPopup.popup_responseAHAH(pageElement, req);
		};
		req.open("GET", url, true);
		req.send(null);
	},
	
	popup: function(x, y, url)
	{
		// get the content from the url
		this.popup_callAHAH(url, "popup_content", "<center>Loading<br><img src=\"/images/ajax-loader-bert2.gif\"></center>");
		// stop page scrolling
		//window.onscroll=function() { window.scrollTo(0,0) }
		
		// Determine how much the visitor had scrolled
		var scrolledX, scrolledY;
		var arrayPageSize;
				
		if( self.pageYOffset ) 
		{
		  scrolledX = self.pageXOffset;
		  scrolledY = self.pageYOffset;
		} 
		else if( document.documentElement && document.documentElement.scrollTop ) {
		  scrolledX = document.documentElement.scrollLeft;
		  scrolledY = document.documentElement.scrollTop;
		} 
		else if( document.body ) {
		  scrolledX = document.body.scrollLeft;
		  scrolledY = document.body.scrollTop;
		}
		
		// Determine the coordinates of the center of the page
		
		var centerX, centerY;
		
		if( self.innerHeight ) 
		{
		  centerX = self.innerWidth;
		  centerY = self.innerHeight;
		} else if( document.documentElement && document.documentElement.clientHeight ) 
		{
		  centerX = document.documentElement.clientWidth;
		  centerY = document.documentElement.clientHeight;
		} else if( document.body ) 
		{
		  centerX = document.body.clientWidth;
		  centerY = document.body.clientHeight;
		}
		
		// determine the correct center position
		var leftOffset = scrolledX + (centerX - x) / 2;
		var topOffset = scrolledY + (centerY - y) / 2;
		// screen the background
		arrayPageSize = this.getPageSize();
		document.getElementById("overlay").style.height = (arrayPageSize[1] + 'px');
		document.getElementById("overlay").style.width = (arrayPageSize[0] + 'px');
		document.getElementById("overlay").style.display = "block";
		
		// display the popup
		// set the size of the two inner elements
		document.getElementById("popup_top_bar").style.width = x + "px";
		//document.getElementById("popup_content").style.width = x + "px";
		// set the size and location of the main window
		document.getElementById("popup_container").style.width = x + "px";
		document.getElementById("popup_container").style.height = y + "px";
		document.getElementById("popup_container").style.top = topOffset + "px";
		document.getElementById("popup_container").style.left = leftOffset + "px";
		document.getElementById("popup_container").style.display = "block";
		
	},
	
	close_popup: function()
	{
		//window.onscroll=null;
		document.getElementById("overlay").style.display = "none";
		document.getElementById("popup_container").style.display = "none";
	},
	
	getPageSize: function(){
		
		var xScroll, yScroll;
		
		if (window.innerHeight && window.scrollMaxY) {	
			xScroll = document.body.scrollWidth;
			yScroll = window.innerHeight + window.scrollMaxY;
		} else if (document.body.scrollHeight > document.body.offsetHeight){ // all but Explorer Mac
			xScroll = document.body.scrollWidth;
			yScroll = document.body.scrollHeight;
		} else { // Explorer Mac...would also work in Explorer 6 Strict, Mozilla and Safari
			xScroll = document.body.offsetWidth;
			yScroll = document.body.offsetHeight;
		}
		
		var windowWidth, windowHeight;
		if (self.innerHeight) {	// all except Explorer
			windowWidth = self.innerWidth;
			windowHeight = self.innerHeight;
		} else if (document.documentElement && document.documentElement.clientHeight) { // Explorer 6 Strict Mode
			windowWidth = document.documentElement.clientWidth;
			windowHeight = document.documentElement.clientHeight;
		} else if (document.body) { // other Explorers
			windowWidth = document.body.clientWidth;
			windowHeight = document.body.clientHeight;
		}	
		
		// for small pages with total height less then height of the viewport
		if(yScroll < windowHeight){
			pageHeight = windowHeight;
		} else { 
			pageHeight = yScroll;
		}
	
		// for small pages with total width less then width of the viewport
		if(xScroll < windowWidth){	
			pageWidth = windowWidth;
		} else {
			pageWidth = xScroll;
		}
	
	
		arrayPageSize = new Array(pageWidth,pageHeight,windowWidth,windowHeight) 
		return arrayPageSize;
	},
	
	getPageScroll: function(){
	
		var yScroll;
	
		if (self.pageYOffset) {
			yScroll = self.pageYOffset;
		} else if (document.documentElement && document.documentElement.scrollTop){	 // Explorer 6 Strict
			yScroll = document.documentElement.scrollTop;
		} else if (document.body) {// all other Explorers
			yScroll = document.body.scrollTop;
		}
	
		arrayPageScroll = new Array('',yScroll) 
		return arrayPageScroll;
	},
	
	initpopup: function()
	{
	
		// the rest of this code inserts html at the top of the page that looks like this:
		//
		// <div id="overlay" class="popup_translucent" style="display: none; background-color: gray; 
		//	width: 100%; height: 100%; position: absolute; left: 0px; top: 0px; z-index: 50000;" onclick="close_popup()">&nbsp;</div>
		//		
		// <div id="popup_container" class="popup_container">
		//	<div id="popup_top_bar" class="popup_top_bar" style="height: 20px; text-align: right;">
		//		<a href="javascript:;" onClick="close_popup(); return false;">CLOSE</a>&nbsp;&nbsp;
		//	</div>
		//	<div id="popup_content" class="popup_content"></div>
		// </div>
		

		var objBody = document.getElementsByTagName("body").item(0);
		
		// create overlay div and hardcode some functional styles (aesthetic styles are in CSS file)
		var objOverlay = document.createElement("div");
		objOverlay.setAttribute('id','overlay');
		objOverlay.onclick = function () {eckPopup.close_popup(); return false;}
		objOverlay.style.display = 'none';
		objOverlay.style.position = 'absolute';
		objOverlay.style.top = '0';
		objOverlay.style.left = '0';
		objOverlay.style.zIndex = '50000';
		objOverlay.style.width = '100%';
		objOverlay.className = "popup_translucent";
		objBody.insertBefore(objOverlay, objBody.firstChild);
		
		// create the popup div to display content
		var objpopup_container = document.createElement("div");
		objpopup_container.setAttribute('id','popup_container');
		objpopup_container.style.display = 'none';
		objpopup_container.style.position = 'absolute';
		objpopup_container.style.zIndex = '50001';
		objpopup_container.className = "popup_container";
		objBody.insertBefore(objpopup_container, objBody.firstChild);
		
		// create the popup_top_bar
		var objpopup_top_bar = document.createElement("div");
		objpopup_top_bar.setAttribute('id','popup_top_bar');
		objpopup_top_bar.className = "popup_top_bar";
		objpopup_top_bar.innerHTML = "<a href=\"javascript:;\" onClick=\"eckPopup.close_popup(); return false;\" class=\"eck_popup_close\"></a>&nbsp;&nbsp;";
		objpopup_container.appendChild(objpopup_top_bar);
		
		// create the popup_content
		var objpopup_content = document.createElement("div");
		objpopup_content.setAttribute('id','popup_content');
		objpopup_content.className = "popup_content";
		objpopup_container.appendChild(objpopup_content);
	},
	
	addLoadEvent: function(func)
	{	
		var oldonload = window.onload;
		if (typeof window.onload != 'function'){
			window.onload = func;
		} else {
			window.onload = function(){
			oldonload();
			func();
			}
		}
	
	}
};


eckPopup.addLoadEvent(eckPopup.initpopup);