var DDSPEED = 10;
var DDTIMER = 15;

var preload1 = new Image();
preload1.src = "../images/ui/main_nav/company_profile_gold.jpg";
var preload2 = new Image();
preload2.src = "../images/ui/main_nav/working_with_wsfg_gold.jpg";
var preload3 = new Image();
preload3.src = "../images/ui/main_nav/wsfg_investors_gold.jpg";

// 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);
    if (id == "one")
    	{ 
    		document.getElementById('navheader_one').src = "../images/ui/main_nav/company_profile_gold.jpg";
    	} else 	if (id == "two") {
  			document.getElementById('navheader_two').src = "../images/ui/main_nav/working_with_wsfg_gold.jpg";
			} else 	if (id == "three") {
  			document.getElementById('navheader_three').src = "../images/ui/main_nav/wsfg_investors_gold.jpg";
  		}
  }else{
    h.timer = setTimeout(function(){ddCollapse(c, id)},50);
  }
}

// collapse the menu //
function ddCollapse(c, id){
  c.timer = setInterval(function(){ddSlide(c,-1)},DDTIMER);
  if (id == "one") {
  	document.getElementById('navheader_one').src = "../images/ui/main_nav/blank.png";
	} else if (id == "two") {
  	document.getElementById('navheader_two').src = "../images/ui/main_nav/blank.png";
	} else if (id == "three") {
  	document.getElementById('navheader_three').src = "../images/ui/main_nav/blank.png";
	}
}

// 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;
  }
  c.style.height = currh + (dist * d) + 'px';
  c.style.opacity = (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);
  }
}


//

function swapin (header_image, swapin_image) {
 	header_image.src = swapin_image;
}