var productImage = null;
var currentThumb = null;
var slideSet = null;

function updateImage(obj){
	!slideSet ? setSlideshow() : 0; 
	if(currentThumb == obj) { return; }
	currentThumb.className = "thumb";
	currentThumb = obj.parentNode;
	currentThumb.className = "thumb selected";
	productImage.src = obj.src.replace(/_thumb/, "");
}

function nextPicture(){ 
	!slideSet ? setSlideshow() : 0; 
	try{updateImage(currentThumb.nextSibling.firstChild)}catch(e){}
}

function previousPicture(){ try{updateImage(currentThumb.previousSibling.firstChild)}catch(e){} }

function setSlideshow(){
	slideSet = true;
	productImage = document.getElementById("productImage");
	currentThumb = document.getElementById("firstThumb");
	cleanWhiteSpace(currentThumb.parentNode)
}

function cleanWhiteSpace(element){
	for (var i = 0; i < element.childNodes.length; i++) {
		var node = element.childNodes[i];
		if (node.nodeType == 3 && !/\S/.test(node.nodeValue)) element.removeChild(node);
	}
}