//SCROLLBAR

var scrollNeg; //height of negative space (hidden beyond viewable area)
var scrollPos; //height of positive space (visible in viewable area)
var scrollButtonTrack; //length of movable scroll button track
var blnDrag = false;

function initScrollbar(){

	setY('scrollButton', 8, 0);
	setY('scrollArea', 0, 0);
		
	if(getH('scrollArea') > getH('scrollContainer')){

		scrollStart = getY('scrollButton');
		scrollLength = getH('scrollTrack') - getH('scrollButton');
		scrollNeg = (getH('scrollContainer') - getH('scrollArea'));
		scrollPos = getH('scrollContainer');
		scrollButtonTrack = getH('scrollTrack') - getH('scrollButton');
	
		yOffset = (getY('divSectionMain') + getY('scrollContainer'));
		
		document.getElementById('scrollButton').onmousedown = startDrag;
		document.onmousemove = doDrag;
		document.onmouseup = stopDrag;
		
		document.getElementById('scrollUP').style.visibility = 'visible';
		document.getElementById('scrollDN').style.visibility = 'visible';
		document.getElementById('scrollButton').style.visibility = 'visible';
		document.getElementById('scrollTrack').style.visibility = 'visible';
		
	}else{
	
		document.getElementById('scrollUP').style.visibility = 'hidden';
		document.getElementById('scrollDN').style.visibility = 'hidden';
		document.getElementById('scrollButton').style.visibility = 'hidden';
		document.getElementById('scrollTrack').style.visibility = 'hidden';
		
	}
}


//SCROLL ARROWS

//called by mousedown event
var interval1;
function scrollDownStart(){
	interval1 = setInterval('scrollDown()', 10);
}
function scrollDownStop(){
	clearInterval(interval1);
}
function scrollDown(){
	if( getY('scrollArea') <= scrollNeg ){
		scrollDownStop();
	}else{
		setY('scrollArea', getY('scrollArea'), -1);
		repoScrollButton();
	}
}

//called by mousedown event
function scrollUpStart(){
	interval1 = setInterval('scrollUp()', 10);
}
function scrollUpStop(){
	clearInterval(interval1);
}
function scrollUp(){
	if( getY('scrollArea') >= 0 ){
		scrollDownStop();
	}else{
		setY('scrollArea', getY('scrollArea'), 1);
		repoScrollButton();
	}
}

function repoScrollButton(){
	intTemp = ((getY('scrollArea') / scrollNeg) * scrollButtonTrack);
	setY('scrollButton', intTemp, 8);
	document.getElementById('scrollButton').style.visibility = 'visible';
}



//SCROLLBUTTON

//called by mousedown event
var yOffsetDelta;
function startDrag(e){
	var objE;	
	if((navigator.appName).indexOf('Netscape') != -1){
		objE = e;
	}else{
		objE = event;
	}
	initY = objE.clientY - yOffset;
	currY = getY('scrollButton');
	yOffsetDelta = currY - initY;
	blnDrag = true;
	return false;
}

function stopDrag(e){
	if(blnDrag){
		var objE;	
		if((navigator.appName).indexOf('Netscape') != -1){
			objE = e;
		}else{
			objE = event;
		}
		blnDrag = false;	
	}
}

function doDrag(e){
	if(blnDrag){
		var objE;	
		if((navigator.appName).indexOf('Netscape') != -1){
			objE = e;
		}else{
			objE = event;
		}
	
		var newY = (objE.clientY - yOffset) + yOffsetDelta;
		if(newY > (scrollLength + scrollStart) ) newY = (scrollLength + scrollStart);
		else if(newY < scrollStart ) newY = scrollStart;
		
		setY('scrollButton', newY, 0);
		repoScrollArea();
		
		return false;
	}
}

function repoScrollArea(){
	iTemp = (((getY('scrollButton') - scrollStart)) / scrollLength);
	setY('scrollArea', (iTemp * scrollNeg), 0);
	document.getElementById('scrollButton').style.visibility = 'visible';
}