// Thanks to Paranoid Ferret Productions for the animation tutorial
// http://blog.paranoidferret.com

var beltWidth = 740; // From CSS
var leftEdge;
var rightEdge;
var scrollTimeout;

function checkButtons() {
	leftEdge = 0;
	rightEdge = beltWidth - hon_beltcontentwidth;
	var leftButton = document.getElementById('hon_beltbuttonleft');
	var rightButton = document.getElementById('hon_beltbuttonright');
	var beltContent = document.getElementById('hon_beltcontent');
	
	if (beltContent.offsetLeft == leftEdge) leftButton.className = 'hon_beltbuttonoff';
	else leftButton.className = 'hon_beltbutton';
	if (beltContent.offsetLeft == rightEdge) rightButton.className = 'hon_beltbuttonoff';
	else rightButton.className = 'hon_beltbutton';
}

function scrollIt(elementID, direction) {
	var e = document.getElementById(elementID);
	if (e == null || e.scrollState == 1 || e.scrollState == -1) return;
	
	leftEdge = 0;
	rightEdge = beltWidth - hon_beltcontentwidth;
	var currentX = e.offsetLeft;
	var relPos = currentX / hon_beltjump;
	var finalX;
	
	if (direction == 'left') {
		finalX = Math.ceil(Math.abs(relPos)) * hon_beltjump * -1 + hon_beltjump;
		if (finalX > leftEdge) finalX = leftEdge;
	} else {
		finalX = Math.ceil(Math.abs(relPos)) * hon_beltjump * -1 - hon_beltjump;
		if (finalX < rightEdge) finalX = rightEdge;
	}

	if (e.scrollState == null) {
		e.scrollState = 2;
	}
	
	e.scrollState = e.scrollState == 2 ? -1 : 1;
	e.hon_scrolltimeLeft = hon_scrolltime;
	scrollTimeout = setTimeout("animateScroll(" + new Date().getTime() + ",'" + elementID + "'," + currentX + "," + finalX + ",'" + direction + "')", 33);
}

function animateScroll(lastTick, elementID, currentX, finalX, direction) { 
	var curTick = new Date().getTime();
	var elapsedTicks = curTick - lastTick;
	
	var e = document.getElementById(elementID);
	
	if (direction == 'left') {
		e.scrollState = -1;
	} else if (direction == 'right') {
		e.scrollState = 1;
	}

	if (e.hon_scrolltimeLeft <= elapsedTicks) {
		e.style.left = finalX + 'px';
		e.scrollState = e.scrollState == 1 ? 2 : -2;
		clearTimeout(scrollTimeout);
		checkButtons();
		return;
	}
	
	e.hon_scrolltimeLeft -= elapsedTicks;
	var xPercent = e.hon_scrolltimeLeft/hon_scrolltime;
	xPercent = 1 - xPercent;
	xTrigPercent = (Math.cos(xPercent * Math.PI - Math.PI) + 1) / 2;
	var deltaX = Math.abs(currentX - finalX);
	var moveX = Math.round(xTrigPercent * deltaX);
	if (direction == 'right') moveX = moveX * -1;
	var newX = currentX + moveX;
	e.style.left = newX + 'px';
	
	scrollTimeout = setTimeout("animateScroll(" + curTick + ",'" + elementID + "'," + currentX + "," + finalX + ",'" + direction + "')", 33);
}