var loadingImage = '/res/js/lightbox/loading.gif';
var closeButton = '/res/js/lightbox/close.gif';

var frameWidth = 600;
var frameHeight = 500;

// getPageScroll()
// Returns array with x,y page scroll values.
// Core code from - quirksmode.org
//
function getPageScroll(){
	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;
}



// getPageSize()
// Returns array with page width, height and window width, height
// Core code from - quirksmode.org
// Edit for Firefox by pHaez
//
function getPageSize(){

	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;
}


//
// pause(numberMillis)
// Pauses code execution for specified time. Uses busy code, not good.
// Code from http://www.faqts.com/knowledge_base/view.phtml/aid/1602
//
function pause(numberMillis) {
	var now = new Date();
	var exitTime = now.getTime() + numberMillis;
	while (true) {
		now = new Date();
		if (now.getTime() > exitTime)
			return;
	}
}


//
// showPopupBox()
// Preloads images. Pleaces new image in PopupBox then centers and displays.
//
function showPopupBox(objLink) {
	// prep objects
	var objOverlay = document.getElementById('overlay');
	var objPopupBox = document.getElementById('PopupBox');
	var objCaption = document.getElementById('PopupBoxCaption');
	var objFrame = document.getElementById('PopupBoxFrame');
	var objLoadingImage = document.getElementById('loadingImage');
	var objPopupBoxDetails = document.getElementById('PopupBoxDetails');

	objOverlay.onclick = function () {hidePopupBox(); return false;}

	var arrayPageSize = getPageSize();
	var arrayPageScroll = getPageScroll();

	// center loadingImage if it exists
	if (objLoadingImage) {
		objLoadingImage.style.top = (arrayPageScroll[1] + ((arrayPageSize[3] - 35 - objLoadingImage.height) / 2) + 'px');
		objLoadingImage.style.left = (((arrayPageSize[0] - 20 - objLoadingImage.width) / 2) + 'px');
		objLoadingImage.style.display = 'block';
	}

	// set height of Overlay to take up whole page and show
	objOverlay.style.height = (arrayPageSize[1] + 'px');
	objOverlay.style.display = 'block';

	// preload image
	//imgPreload = new Image();

	objFrame.src = objLink.href;

	// center PopupBox and make sure that the top and left values are not negative
	// and the image placed outside the viewport
	var PopupBoxTop = arrayPageScroll[1] + ((arrayPageSize[3] - 35 - frameHeight) / 2);
	var PopupBoxLeft = ((arrayPageSize[0] - 20 - frameWidth) / 2);

	objPopupBox.style.top = (PopupBoxTop < 0) ? "0px" : PopupBoxTop + "px";
	objPopupBox.style.left = (PopupBoxLeft < 0) ? "0px" : PopupBoxLeft + "px";

	objPopupBoxDetails.style.width = frameWidth + 'px';

	if(objLink.getAttribute('title')){
		objCaption.style.display = 'block';
		//objCaption.style.width = imgPreload.width + 'px';
		objCaption.innerHTML = objLink.getAttribute('title');
	} else {
		objCaption.style.display = 'none';
	}

	// A small pause between the image loading and displaying is required with IE,
	// this prevents the previous image displaying for a short burst causing flicker.
	if (navigator.appVersion.indexOf("MSIE")!=-1){
		pause(250);
	}

	if (objLoadingImage) {	objLoadingImage.style.display = 'none'; }

	// Hide select boxes as they will 'peek' through the image in IE
	selects = document.getElementsByTagName("select");
    for (i = 0; i != selects.length; i++) {
    	selects[i].style.visibility = "hidden";
    }

	objPopupBox.style.display = 'block';

	// After image is loaded, update the overlay height as the new image might have
	// increased the overall page height.
	arrayPageSize = getPageSize();
	objOverlay.style.height = (arrayPageSize[1] + 'px');
}

//
// hidePopupBox()
//
function hidePopupBox() {
	// get objects
	objOverlay = document.getElementById('overlay');
	objPopupBox = document.getElementById('PopupBox');

	// hide PopupBox and overlay
	objOverlay.style.display = 'none';
	objPopupBox.style.display = 'none';

	// make select boxes visible
	selects = document.getElementsByTagName("select");
    for (i = 0; i != selects.length; i++) {
		selects[i].style.visibility = "visible";
	}
}




//
// initPopupBox()
// Function runs on window load, going through link tags looking for rel="PopupBox".
// These links receive onclick events that enable the PopupBox display for their targets.
// The function also inserts html markup at the top of the page which will be used as a
// container for the overlay pattern and the inline image.
//
function initPopupBox() {

	if (!document.getElementsByTagName){ return; }
	var anchors = document.getElementsByTagName("a");

	// loop through all anchor tags
	for (var i=0; i<anchors.length; i++){
		var anchor = anchors[i];

		if (anchor.getAttribute("href") && (anchor.getAttribute("rel") == "popupbox")){
			anchor.onclick = function () {showPopupBox(this); return false;}
		}
	}

	var objBody = document.getElementsByTagName("body").item(0);

	// create overlay div and hardcode some functional styles (aesthetic styles are in CSS file)
	if(!document.getElementById('overlay')) {
		var objOverlay = document.createElement("div");
		objOverlay.setAttribute('id','overlay');
		//objOverlay.onclick = function () {hidePopupBox(); return false;}
		objOverlay.style.display = 'none';
		objOverlay.style.position = 'absolute';
		objOverlay.style.top = '0';
		objOverlay.style.left = '0';
		objOverlay.style.zIndex = '90';
 		objOverlay.style.width = '100%';
		objBody.insertBefore(objOverlay, objBody.firstChild);

		var arrayPageSize = getPageSize();
		var arrayPageScroll = getPageScroll();

		// preload and create loader image
		var imgPreloader = new Image();

		// if loader image found, create link to hide PopupBox and create loadingimage
		imgPreloader.onload=function(){

			var objLoadingImageLink = document.createElement("a");
			objLoadingImageLink.setAttribute('href','#');
			objLoadingImageLink.onclick = function () {hidePopupBox(); return false;}
			objOverlay.appendChild(objLoadingImageLink);

			var objLoadingImage = document.createElement("img");
			objLoadingImage.src = loadingImage;
			objLoadingImage.setAttribute('id','loadingImage');
			objLoadingImage.style.position = 'absolute';
			objLoadingImage.style.zIndex = '150';
			objLoadingImageLink.appendChild(objLoadingImage);

			imgPreloader.onload=function(){};	//	clear onLoad, as IE will flip out w/animated gifs

			return false;
		}
		imgPreloader.src = loadingImage;
	} else {
		objOverlay = document.getElementById('overlay');
	}


	// create PopupBox div, same note about styles as above
	var objPopupBox = document.createElement("div");
	objPopupBox.setAttribute('id','PopupBox');
	objPopupBox.style.display = 'none';
	objPopupBox.style.position = 'absolute';
	objPopupBox.style.zIndex = '100';
	objBody.insertBefore(objPopupBox, objOverlay.nextSibling);

	// create link
	var objLink = document.createElement("a");
	objLink.setAttribute('href','#');
	objLink.setAttribute('title','Schließen');
	objLink.onclick = function () {hidePopupBox(); return false;}
	objPopupBox.appendChild(objLink);

	// preload and create close button image
	var imgPreloadCloseButton = new Image();

	// if close button image found,
	imgPreloadCloseButton.onload=function(){

		var objCloseButton = document.createElement("img");
		objCloseButton.src = closeButton;
		objCloseButton.setAttribute('id','closeButton');
		objCloseButton.style.position = 'absolute';
		objCloseButton.style.zIndex = '200';
		objLink.appendChild(objCloseButton);

		return false;
	}

	imgPreloadCloseButton.src = closeButton;

	// create iFrame
	var objFrame = document.createElement("iframe");
	objFrame.setAttribute('id','PopupBoxFrame');
	objFrame.setAttribute('width',frameWidth);
	objFrame.setAttribute('height',frameHeight);
	objFrame.setAttribute('frameborder', '0');

	objLink.appendChild(objFrame);

	// create details div, a container for the caption and keyboard message
	var objPopupBoxDetails = document.createElement("div");
	objPopupBoxDetails.setAttribute('id','PopupBoxDetails');
	objPopupBox.appendChild(objPopupBoxDetails);

	// create caption
	var objCaption = document.createElement("div");
	objCaption.setAttribute('id','PopupBoxCaption');
	objCaption.style.display = 'none';
	objPopupBoxDetails.appendChild(objCaption);

	// create keyboard message
	var objKeyboardMsg = document.createElement("div");
	objKeyboardMsg.setAttribute('id','keyboardMsg');
	objKeyboardMsg.innerHTML = '<a href="#" onclick="hidePopupBox(); return false;">Schließen</a>';
	objPopupBoxDetails.appendChild(objKeyboardMsg);


}