var DDSPEED = 10;
var DDTIMER = 15;
var x = 1;
// main function to handle the mouse events //
function ddMenu(id,d){
  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){
      c.style.display = 'block';
      c.style.height = 'auto';
      c.maxh = c.offsetHeight;
      c.style.height = '0px';
    }
    c.timer = setInterval(function(){ddSlide(c,1)},DDTIMER);
  }else{
    h.timer = setTimeout(function(){ddCollapse(c)},50);
  }
}

// collapse the menu //
function ddCollapse(c){
	x=2;
  	c.timer = setInterval(function(){ddSlide(c,-1)},DDTIMER);
}

// cancel the collapse if a user rolls over the dropdown //
function cancelHide(id){
  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)},DDTIMER);
  }
}

// incrementally expand/contract the dropdown and change the opacity //
function ddSlide(c,d){
	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 = 1;
  	}
  	if(x==2){
	  	aHe = c.style.height;
		nHe = currh + (dist * d) + 'px';
		//alert(c.style.height+'-'+currh+'-'+dist+'-'+d);
	}
	if(x==2){
		if(aHe == nHe){
			c.style.height = currh + ((dist+1) * d) + 'px';	
		}else{
			if(dist == 0){
				dist = 2;
			}
			c.style.height = currh + (dist * d) + 'px';
		}
	}else{
	  	c.style.height = currh + (dist * d) + 'px';
	}
  	c.style.opacity = currh / c.maxh;
	c.style.filter = 'alpha(opacity=' + (currh * 100 / c.maxh) + ')'; 
	if( (currh < 2 && d != 1) || (currh > (c.maxh - 2) && d == 1) ){
		clearInterval(c.timer);
  	}
}