// lets do this

var forPreloading = new Array;

window.onload = init;

function init()
{
	var mainMenu = document.getElementById('main_navigation');
	var hyperLinks = mainMenu.getElementsByTagName('a');
	var rollImage;
	
	for (var i = 0; i < hyperLinks.length; i++) 
	{
		rollImage = hyperLinks[i].getElementsByTagName('img');
		if (rollImage[0])
		{
			registerPreload(rollImage[0]);
			rollImage[0].onmouseover = rollOver;
			rollImage[0].onmouseout = overRoll;
		}
	}
	
	imagePreload();
	hoverMenu();
}

function registerPreload(imageTreat)
{
	var newSrc = imageTreat.src.split(".gif");
	var newLength = forPreloading.length + 1;
	forPreloading[newLength] = newSrc[0] + '_on.gif';
}

// Preload Images
// -------------------------------------------- //

function imagePreload() {
	var set_images = new Array();
				
	for (var i = 0; i < forPreloading.length; i++) {
		set_images[i] = new Image;
		set_images[i].src = forPreloading[i];
	}
}

// Rollover
// -------------------------------------------- //

function rollOver() {
	var newSrc = this.src.split(".gif");
	this.src = newSrc[0] + "_on.gif";
}

// Undo Rollover
// -------------------------------------------- //

function overRoll() {
	var newSrc = this.src.split("_on.gif");
	this.src = newSrc[0] + ".gif";
}

// Hover Menu
// -------------------------------------------- //

function hoverMenu() {
	var sfEls = document.getElementById("main_navigation").getElementsByTagName("LI");
	for (var i = 0; i < sfEls.length; i++) {
		sfEls[i].onmouseover=function() {
			this.className = "sfhover";
		}
		sfEls[i].onmouseout=function() {
			this.className= "sf";
		}
	}
}