function addClassName(element, className) {
	var classes = element.className.split(/\s+/);
	var found = false;
	for (var i = 0; i < classes.length; i++) {
		if (className == classes[i]) {
			found = true;
			break;
		}
	}
	if (!found) {
		classes.push(className);
		element.className = classes.join(' ');
	}
}

function removeClassName(element, className) {
	var classes = element.className.split(/\s+/);
	var found= false;
	for (var i = 0; i < classes.length; i++) {
		if (className == classes[i]) {
			found = true;
			delete(classes[i]);
			break;
		}
	}
	if (found) {
		element.className = classes.join(' ');
	}
}

function hasClassName(element, className) {
	var classes = element.className.split(/\s+/);
	var found = false;
	for (var i = 0; i < classes.length; i++) {
		if (className == classes[i]) {
			return true;
		}
	}
	return false;
}

window.onload = function() {

	// menu image rollovers
	var linkArr = document.getElementsByTagName('A');
	var preload = [];
	for (var i = 0; i < linkArr.length; i++) {
		if ( hasClassName(linkArr[i], 'rollover') ) {
			imgEl = linkArr[i].getElementsByTagName('IMG')[0];
			if (imgEl) {			
				preload[i]             = new Image;
				rollsrc                = imgEl.src.replace(/(.+)\.(gif|jpg|png)/, "$1_over.$2");
				preload[i].src         = rollsrc;
				linkArr[i].imgEl       = imgEl;
				linkArr[i].rollsrc     = rollsrc;
				linkArr[i].origsrc     = imgEl.src;
				linkArr[i].onmouseover = function() {
					this.imgEl.src     = this.rollsrc;
				}
				linkArr[i].onmouseout  = function() {
					this.imgEl.src     = this.origsrc;
				}
			}
		}
	}
	
	// add product image event handlers
	var imageDiv = document.getElementById('product-shots');
	if (imageDiv) {
		var linkArr  = imageDiv.getElementsByTagName('A');
		for (var i = 0; i < linkArr.length; i++) {
			linkArr[i].onclick = function() {
				document.getElementById('large-image').src = this.href;
				return false;
			}
		}
	}
}