var opacity; //global opacity var
var f1;	//fade 1 (the div to fade)
var f2; //fade 2 (the other div to fade)
var num1; //picture number 1
var num2; //picture number 2
var direction = "up";
var sponsorIndex;

function body_load() {
	//setTimeout("updateImages()", 3000);
	opacity = 2;
	f1 = document.getElementById("titleBar1");
	f2 = document.getElementById("titleBar2");
	num1 = getRandomNumber(-1);
	num2 = getRandomNumber(num2);
	f1.style.background = "url(/images/headers/" + num1 + ".jpg)";
	f2.style.background = "url(/images/headers/" + num2 + ".jpg)";
	sponsorIndex = Math.floor(Math.random()*numberOfSponsors);
	updateSponsor();
//	resizeImages();
}

function resizeImages() {
	var imgs = document.getElementsByTagName("img");
	for ( var i=0; i<imgs.length; i++ )
	{
		if ( imgs[i].getAttribute("resizeMod") == "on" )
		{
			resizeImage( imgs[i] );
		}
	}
}

//function rmw_img_loaded(img) { }

function resizeImage(img) {
	img.style.padding = "0px";
	img.style.margin = "0px";
	if (img.width > 500)
	{
		img.style.width = "500";
	}
}

function getRandomNumber(unavailable) {
	var num;
	do
	{
		num = Math.floor(Math.random()*numberOfImages) + 1;
	}
	while (num == unavailable);
	return num;
	
}

function truckPic_mouseOver(picSmall) {
	var picLarge = document.getElementById("picLarge");
	picLarge.src = picSmall.src;
}

function updateImages() {
	step = 2;

	//internet explorer
	f1.style.filter = "alpha(opacity=" + opacity + ")"; 
	f2.style.filter = "alpha(opacity=" + ((opacity - 100) * -1) + ")";

	//firefox
	f1.style.opacity = opacity / 100;
	f2.style.opacity = (opacity - 100) * -1 / 100;

	if (opacity == 100) {
		direction = "down";
		num2 = getRandomNumber(num1);
		f2.style.background = "url(/images/headers/" + num2 + ".jpg)";

	}
	if (opacity == 0) {
		direction = "up";
		num1 = getRandomNumber(num2);
		f1.style.background = "url(/images/headers/" + num1 + ".jpg)";
	}

	if (direction == "up") {
		opacity += step;
	} else {
		opacity -= step;
	}

	if (opacity == 100 || opacity == 0) {
		setTimeout("updateImages()", 4000);
	} else {
		setTimeout("updateImages()", 100);
	}
}

//var numberOfSponsors is defined in php
function updateSponsor() {
	var sponsorLink = document.getElementById("sponsorLink");
	imgNumber = sponsorIndex++;
	if (imgNumber >= numberOfSponsors)
	{
		imgNumber = 0;
		sponsorIndex = 1;
	}
	sponsorLink.style.background = "url(/images/sponsors/bottomBar/" + sponsors[imgNumber] + ")";

	var start = 0;
	var end = sponsors[imgNumber].lastIndexOf(".");
	var link = "http://www." + sponsors[imgNumber].substring(start, end).replace("_", ".");
	sponsorLink.href = link;
	setTimeout("updateSponsor()", 7000);

}