var scrollUpBtn;
var scrollDownBtn;
var scrollPanel;
var scrollHandle;
var content;
var container;

var handleHeight;
var contentHeight;

var handlePos = 0;
var contentPos = 0;

var scrollDistance = 30;

var aktInterval;

function initialize(){
	scrollUpBtn = document.getElementById("scrollup");
	scrollDownBtn = document.getElementById("scrolldown");
	scrollPanel = document.getElementById("scrollpanel");
	scrollHandle = document.getElementById("scrollhandle");
	content = document.getElementById("content");
	contentHeight = content.offsetHeight - 400;
	container = document.getElementById("contentcontainer");
	scrollUpBtn.onmousedown = scrollUp;
	scrollDownBtn.onmousedown = scrollDown;
	scrollUpBtn.onmouseup = resetInterval;
	scrollDownBtn.onmouseup = resetInterval;
}

function scrollUpFF(){
	if(contentPos < 0){
		//handlePos -= scrollDistance;
		//scrollHandle.style.top = handlePos.toString() + "px";
		contentPos += scrollDistance;
		content.style.top = contentPos.toString() + "px";
	}
}

function scrollDownFF(){
	//handlePos += scrollDistance;
	//scrollHandle.style.top = handlePos.toString() + "px";
	if(contentPos >= (0 - contentHeight)){
		contentPos -= scrollDistance;
		content.style.top = contentPos.toString() + "px";
	}
}

function scrollUpIE(){
	if(contentPos < 0){
		//handlePos -= scrollDistance;
		//scrollHandle.style.top = handlePos.toString() + "px";
		contentPos += scrollDistance;
		content.style.top = contentPos.toString() + "px";
	}
}

function scrollDownIE(){
	//handlePos += scrollDistance;
	//scrollHandle.style.top = handlePos.toString() + "px";
	if(contentPos >= (0 - contentHeight)){
		contentPos -= scrollDistance;
		content.style.top = contentPos.toString() + "px";
	}
}

function scrollDown() {
	if(!document.all) { scrollDownFF(); aktInterval = window.setInterval("scrollDownFF()", 200); }
	else { scrollDownIE(); aktInterval = window.setInterval("scrollDownIE()", 200); }
}

function scrollUp() {
	if(!document.all) { scrollUpFF(); aktInterval = window.setInterval("scrollUpFF()", 200); }
	else { scrollUpIE(); aktInterval = window.setInterval("scrollUpIE()", 200); }
}

function resetInterval() {
	window.clearInterval(aktInterval);
}



window.onload = initialize;