window.onload = function()
{
	var menu_images, actions;
	if (menu_images = document.getElementById("menu")) {
		menu_images = menu_images.getElementsByTagName("IMG");
		/**
		 * Preload Images
		 */
		var preload = ["admin", "home", "internaltasks", "leads", "newtask", "review", "reviewhours"];
		do_preload(preload, "assets/img/menu", "jpg");
		/**
		 * Rollover Images
		 */
		do_rollover(menu_images, "jpg");
	}
	if (actions = document.getElementById("actions")) {
		actions = actions.getElementsByTagName("IMG");
		/**
		 * Preload Images
		 */
		var preload = ["delete", "close", "view-answered", "view-closed", "refresh", "preferences", "responses", "categories", "representatives", "my-account", "diy-knowledgebase"];
		do_preload(preload, "assets/img/buttons", "gif");
		/**
		 * Rollover Images
		 */
		do_rollover(actions, "png");
	}
}

/**
 * Rollover function
 */
function do_rollover( images, ext, exclude_class )
{
	var regex = [new RegExp("\\." + ext,"i"), new RegExp("\\-dn." + ext,"i")];
	if (!exclude_class) exclude_class = "";
	for (var i = 0; i < images.length; i++) {
		if (images[i].className == exclude_class) {
			images[i].onmouseover = function() { this.src = this.src.replace(regex[0], "-dn." + ext); }
			images[i].onmouseout = function() { this.src = this.src.replace(regex[1], "." + ext); }
		}
	}
}

/**
 * Preload Images
 */

function do_preload(images, url, ext)
{
	for (var i = 0; i < images.length; i++) {
		var image = document.createElement("IMG");
		image.src = url + "/" + images[i] + "-dn." + ext;
		image.className = "preload";
		document.body.appendChild(image);
	}
}