var DDSPEED = 8;
var DDTIMER = 10;

// main function to handle the mouse events //
//function ddMenu(id,d){
function ddMenu(id,d,upper_bottom){
	var h = document.getElementById(id + '-ddheader');
	var c = document.getElementById(id + '-ddcontent');
	clearInterval(c.timer);
	if(d == 1){
		clearTimeout(h.timer);
		if(c.maxh && c.maxh <= c.offsetHeight){return}
		else if(!c.maxh){
			if (upper_bottom == 'upper'){
				c.style.top = '-' + c.offsetHeight + 'px';
			}
			c.style.display = 'block';
			c.style.height = 'auto';
			c.maxh = c.offsetHeight;
			c.style.height = '0px';
		}
		c.timer = setInterval(function(){ddSlide(c,1,upper_bottom)},DDTIMER);
	}else{
		h.timer = setTimeout(function(){ddCollapse(c,upper_bottom)},50);
	}
}


// collapse the menu //
function ddCollapse(c,upper_bottom){
	c.timer = setInterval(function(){ddSlide(c,-1,upper_bottom)},DDTIMER);
}

// cancel the collapse if a user rolls over the dropdown //
function cancelHide(id,upper_bottom){
	var h = document.getElementById(id + '-ddheader');
	var c = document.getElementById(id + '-ddcontent');
	clearTimeout(h.timer);
	clearInterval(c.timer);
	if(c.offsetHeight < c.maxh){
		c.timer = setInterval(function(){ddSlide(c,1,upper_bottom)},DDTIMER);
	}
}

// incrementally expand/contract the dropdown and change the opacity //
function ddSlide(c,d,upper_bottom){
	var currh = c.offsetHeight;
	var dist;
	//if(d == 1){
	//	dist = (Math.round((c.maxh - currh) / DDSPEED));
	//}else{
	//	dist = (Math.round(currh / DDSPEED));
	//}
	//if(dist <= 1 && d == 1){
		dist = 4;
	//}

	if (currh < 4 && d != 1) {
		dist = currh;
	}

	if ((c.maxh - currh) < 4 && d == 1) {
		dist = c.maxh - currh;
	}


	if (upper_bottom == 'upper'){
		c.style.top = parseInt(c.style.top.replace('px','')) - parseInt(dist * d) + 'px';
	}
	c.style.height = currh + (dist * d) + 'px';
	if(currh > (c.maxh - 2) && d == 1){
		clearInterval(c.timer);
	}

	if (currh < 1 && d != 1) {
		clearInterval(c.timer);
	}
}