// Scrollbar Handling

/* **************************** MoveButton **************************** */

var sd = document.getElementById("scrollme");
var sb = document.getElementById("moveme");

var base = 302;//parseInt(sd.style.top);

var bu = document.getElementById("up");
var bd = document.getElementById("down");

if ( sd.offsetHeight > sd.scrollHeight-1 ) {
	sb.style.top = "-100px";
	bu.style.top = "-100px";
	bd.style.top = "-100px";
	document.getElementById("scrollbar").style.top = "-1000px";
} else {
	sd.style.overflow = "auto";
}

var shouldScrollUp = 0;
var shouldScrollDown = 0;

bu.addEventListener("mousedown",performScrollUp,false);
bu.addEventListener("mouseup",cancelScroll,false);
//bu.addEventListener("mousemove",resumeScroll,false);
bu.addEventListener("mouseout",cancelScroll,false);

bd.addEventListener("mousedown",performScrollDown,false);
bd.addEventListener("mouseup",cancelScroll,false);
//bd.addEventListener("mousemove",resumeScroll,false);
bd.addEventListener("mouseout",cancelScroll,false);

scrollContentUp();
scrollContentDown();

function performScrollUp(e) {
	shouldScrollUp = 1;
}
function performScrollDown(e) {
	shouldScrollDown = 1;
}
function cancelScroll(e) {
	shouldScrollUp = 0;
	shouldScrollDown = 0;
}

function updateScrollPosition() {
	sb.style.top = (base + Math.round((289)*sd.scrollTop/(sd.scrollHeight-sd.offsetHeight+2))) + "px";
}

function scrollContentUp() {
	if ( shouldScrollUp ) sd.scrollTop = sd.scrollTop + Math.round(-1-sd.scrollHeight/sd.offsetHeight);
	window.setTimeout("scrollContentUp()",10);
}
function scrollContentDown() {
	if ( shouldScrollDown ) sd.scrollTop = sd.scrollTop + Math.round(1+sd.scrollHeight/sd.offsetHeight);
	window.setTimeout("scrollContentDown()",10);
}


/* **************************** Menu **************************** */

document.getElementById(activePage).src = "media/menu/" + activePage + "_a.png";

function menuOver(sender) {
	if ( sender.src.indexOf("_a") < 0 )
		sender.src = sender.src.substring(0,sender.src.length-4) + "_h.png";
}
function menuOut(sender) {
	if ( sender.src.indexOf("_a") < 0 )
		sender.src = sender.src.substring(0,sender.src.length-6) + ".png";
}


/* **************************** Mail **************************** */

function mail(zero,one,two) {
	window.open("mailto:" + one + "@" + two,"_self");
}

/* **************************** Sponsors **************************** */

var main_bkgnd = document.getElementById("main_bkgnd");
var main_content = document.getElementById("main_content");
var tmp_bkgnd;
var tmp_content;

function show_sponsor(img) {
	var path = img.src;
	var number = path.substring(path.lastIndexOf("/")+1,path.lastIndexOf("."));
	
	tmp_bkgnd = main_bkgnd.src;
	tmp_content = main_content.innerHTML;
	
	if ( validSponsorImages[number+'.png'] == true ) {
		main_content.innerHTML = "";
		main_bkgnd.src = "sponsoren_gross/"+number+".png";
	}
}

function hide_sponsor() {
	main_bkgnd.src = tmp_bkgnd;
	main_content.innerHTML = tmp_content;
}