/*
	The following code was edited from the LightBox script:
	
	Lightbox JS: Fullsize Image Overlays 
	by Lokesh Dhakar - http://www.huddletogether.com

	For more information on this script, visit:
	http://huddletogether.com/projects/lightbox/

*/

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;
}

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;
}

function showLightbox()
{
	// prep objects
	var objOverlay = document.getElementById('overlay');
	var objLightbox = document.getElementById('lightbox');
	
	var arrayPageSize = getPageSize();
	var arrayPageScroll = getPageScroll();

	// set height of Overlay to take up whole page and show
	objOverlay.style.height = (arrayPageSize[1] + 'px');
	objOverlay.style.display = 'block';
	
	// center lightbox and make sure that the top and left values are not negative
	// and the image placed outside the viewport
	var lightboxTop = arrayPageScroll[1] + ((arrayPageSize[3] - 35) / 2);
	var lightboxLeft = ((arrayPageSize[0] - 20) / 2);
	
	objLightbox.style.top = (lightboxTop < 0) ? "0px" : lightboxTop + "px";
	objLightbox.style.left = (lightboxLeft < 0) ? "0px" : lightboxLeft + "px";
	objLightbox.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');

	return false;
}

function hideLightbox()
{
	// get objects
	objOverlay = document.getElementById('overlay');
	objLightbox = document.getElementById('lightbox');

	// hide lightbox and overlay
	objOverlay.style.display = 'none';
	objLightbox.style.display = 'none';
}