var gPopupMask = null;
var gPopupContainer = null;
var gPopupTitle = null;
var gPopupIsShown = false;
var gHideSelects = false;

var gTabIndexes = new Array();
// Pre-defined list of tags we want to disable/enable tabbing into
var gTabbableTags = new Array("A","BUTTON","TEXTAREA","INPUT","IFRAME");	

addEvent(window, "resize", centerPopWin);
addEvent(window, "scroll", centerPopWin);
window.onscroll = centerPopWin;

function centerPopWin(width, height) {
	if (gPopupIsShown == true) {
		if (width == null || isNaN(width)) {
			width = gPopupContainer.offsetWidth;
		}
		if (height == null) {
			height = gPopupContainer.offsetHeight;
		}
		
		//var theBody = document.documentElement;
		var theBody = document.getElementsByTagName("BODY")[0];
		//theBody.style.overflow = "hidden";
		var scTop = parseInt(getScrollTop(),10);
		var scLeft = parseInt(theBody.scrollLeft,10);
		setMaskSize();
		
		//window.status = gPopupMask.style.top + " " + gPopupMask.style.left + " " + gi++;
		
		var titleBarHeight = parseInt(gPopupTitle.offsetHeight, 10);
		
		var fullHeight = getViewportHeight();
		var fullWidth = getViewportWidth();
		
		gPopupContainer.style.top = "100px";//(scTop + ((fullHeight - (height+titleBarHeight)) / 2)) + "px";
		gPopupContainer.style.left = (scLeft + ((fullWidth - width) / 2)) + "px";
		//alert(fullWidth + " " + width + " " + gPopupContainer.style.left);
	}
}

function setMaskSize() {
	var theBody = document.getElementsByTagName("BODY")[0];
			
	var fullHeight = getViewportHeight();
	var fullWidth = getViewportWidth();
	
	// Determine what's bigger, scrollHeight or fullHeight / width
	if (fullHeight > theBody.scrollHeight) {
		popHeight = fullHeight;
	} else {
		popHeight = theBody.scrollHeight;
	}
	
	if (fullWidth > theBody.scrollWidth) {
		popWidth = fullWidth;
	} else {
		popWidth = theBody.scrollWidth;
	}
	
	gPopupMask.style.height = popHeight + "px";
	gPopupMask.style.width = popWidth + "px";

}

function hidePopWin(callReturnFunc) {
	gPopupIsShown = false;
	var theBody = document.getElementsByTagName("BODY")[0];
	//theBody.removeAttribute("onload");
	removeEvent(window, 'load', showPopWin, false);
	theBody.style.overflow = "";
	restoreTabIndexes();
	if (gPopupMask == null) {
		return;
	}
	gPopupMask.style.display = "none";
	gPopupContainer.style.display = "none";

	// display all select boxes
	if (gHideSelects == true) {
		displaySelectBoxes();
	}
}

/**
 * Sets the popup title based on the title of the html document it contains.
 * Uses a timeout to keep checking until the title is valid.
 */
function setPopTitle() {
	return;
	if (window.frames["popupFrame"].document.title == null) {
		window.setTimeout("setPopTitle();", 10);
	} else {
		document.getElementById("popupTitle").innerHTML = window.frames["popupFrame"].document.title;
	}
}

// Tab key trap. iff popup is shown and key was [TAB], suppress it.
// @argument e - event - keyboard event that caused this function to be called.
function keyDownHandler(e) {
    if (gPopupIsShown && e.keyCode == 9)  return false;
}

// For IE.  Go through predefined tags and disable tabbing into them.
function disableTabIndexes() {
	if (document.all) {
		var i = 0;
		for (var j = 0; j < gTabbableTags.length; j++) {
			var tagElements = document.getElementsByTagName(gTabbableTags[j]);
			for (var k = 0 ; k < tagElements.length; k++) {
				gTabIndexes[i] = tagElements[k].tabIndex;
				tagElements[k].tabIndex="-1";
				i++;
			}
		}
	}
}

// For IE. Restore tab-indexes.
function restoreTabIndexes() {
	if (document.all) {
		var i = 0;
		for (var j = 0; j < gTabbableTags.length; j++) {
			var tagElements = document.getElementsByTagName(gTabbableTags[j]);
			for (var k = 0 ; k < tagElements.length; k++) {
				tagElements[k].tabIndex = gTabIndexes[i];
				tagElements[k].tabEnabled = true;
				i++;
			}
		}
	}
}


/**
* Hides all drop down form select boxes on the screen so they do not appear above the mask layer.
* IE has a problem with wanted select form tags to always be the topmost z-index or layer
*/
function hideSelectBoxes() {
	for(var i = 0; i < document.forms.length; i++) {
		for(var e = 0; e < document.forms[i].length; e++){
			if(document.forms[i].elements[e].tagName == "SELECT") {
				document.forms[i].elements[e].style.visibility="hidden";
			}
		}
	}
}

/**
* Makes all drop down form select boxes on the screen visible so they do not reappear after the dialog is closed.
* IE has a problem with wanted select form tags to always be the topmost z-index or layer
*/
function displaySelectBoxes() {
	for(var i = 0; i < document.forms.length; i++) {
		for(var e = 0; e < document.forms[i].length; e++){
			if(document.forms[i].elements[e].tagName == "SELECT") {
			document.forms[i].elements[e].style.visibility="visible";
			}
		}
	}
}

function addEvent(obj, evType, fn){
 if (obj.addEventListener){
    obj.addEventListener(evType, fn, false);
    return true;
 } else if (obj.attachEvent){
    var r = obj.attachEvent("on"+evType, fn);
    return r;
 } else {
    return false;
 }
}
function removeEvent(obj, evType, fn, useCapture){
  if (obj.removeEventListener){
    obj.removeEventListener(evType, fn, useCapture);
    return true;
  } else if (obj.detachEvent){
    var r = obj.detachEvent("on"+evType, fn);
    return r;
  } else {
    alert("Handler could not be removed");
  }
}

function getViewportHeight() {
	if (window.innerHeight!=window.undefined) return window.innerHeight;
	if (document.compatMode=='CSS1Compat') return document.documentElement.clientHeight;
	if (document.body) return document.body.clientHeight; 

	return window.undefined; 
}
function getViewportWidth() {
	var offset = 17;
	var width = null;
	if (window.innerWidth!=window.undefined) return window.innerWidth; 
	if (document.compatMode=='CSS1Compat') return document.documentElement.clientWidth; 
	if (document.body) return document.body.clientWidth; 
}

/**
 * Gets the real scroll top
 */
function getScrollTop() {
	if (self.pageYOffset) // all except Explorer
	{
		return self.pageYOffset;
	}
	else if (document.documentElement && document.documentElement.scrollTop)
		// Explorer 6 Strict
	{
		return document.documentElement.scrollTop;
	}
	else if (document.body) // all other Explorers
	{
		return document.body.scrollTop;
	}
}
function getScrollLeft() {
	if (self.pageXOffset) // all except Explorer
	{
		return self.pageXOffset;
	}
	else if (document.documentElement && document.documentElement.scrollLeft)
		// Explorer 6 Strict
	{
		return document.documentElement.scrollLeft;
	}
	else if (document.body) // all other Explorers
	{
		return document.body.scrollLeft;
	}
}