var DDSPEED = 4;
var DDTIMER = 15;

// main function to handle the mouse events //
function ddMenu(id,d){
	var h = document.getElementById(id + '-ddheader');
	var c = document.getElementById(id + '-ddcontent');
	var img = document.getElementById(id + '-navbutton');
	
  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';
    }
	//$(img).attr('src', nav_on);
	$(img).css("color", "#666666");
	$(h).addClass('dtON')
    c.timer = setInterval(function(){ddSlide(c,1,id)},DDTIMER);
  }else{
  	//$(img).attr('src', nav_off);
	$(h).removeClass('dtON')
    h.timer = setTimeout(function(){ddCollapse(c,id)},50);
  }
}

// collapse the menu //
function ddCollapse(c,id){
  c.timer = setInterval(function(){ddSlide(c,-1,id)},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');
  var img = document.getElementById(id + '-navbutton');
	
	$(h).addClass('dtON')
	$(img).css("color", "#666666");
  
  clearTimeout(h.timer);
  clearInterval(c.timer);
  if(c.offsetHeight < c.maxh){
    c.timer = setInterval(function(){ddSlide(c,1, id)},DDTIMER);
  }
}

// incrementally expand/contract the dropdown and change the opacity //
function ddSlide(c,d, id){
  var currh = c.offsetHeight;
  var dist;
  var mysetting;
  var img = document.getElementById(id + '-navbutton');
  var dropd = document.getElementById(id + '-ddheader');
	
  
  if(d == 1){
    dist = (Math.round((c.maxh - currh) / DDSPEED));
	$(dropd).addClass('dtON')
	$(img).css("color", "#666666");
  }else{
    dist = (Math.round(currh / DDSPEED));
	$(dropd).removeClass('dtON')
	$(img).css("color", "#ffffff");
  }
  
  if(dist <= 1 && d == 1){
    dist = 1;
  }
  
  c.style.height = currh + (dist * d) + 'px';
  mysetting = (currh / c.maxh)+1;
  //c.style.filter = 'alpha(opacity=' + (currh * 100 / c.maxh) + ')';
   if((currh < 2 && d != 1) || (currh > (c.maxh - 2) && d == 1)){
   
    clearInterval(c.timer);
  }
  
}