// JavaScript Document
var slideshow_images = new Array("xml_image.php?imageID=2760&image_size=large"
,"xml_image.php?imageID=2764&image_size=large"
,"xml_image.php?imageID=2762&image_size=large"
,"xml_image.php?imageID=2763&image_size=large"
,"xml_image.php?imageID=2765&image_size=large"
);
var currentKey = 0;
var showComplete = false;

function set_slideshow (key) {
	document.getElementById('slideshow_window').style.backgroundImage = "url(" + slideshow_images[key] + ")";
	if (!showComplete) {
		simplePreload(key);
	}
}

var TimeToFade = 1000.0;

function fade(eid)
{
  var element = document.getElementById(eid);
  if(element == null)
    return;
   
  if(element.FadeState == null)
  {
	set_slideshow(currentKey);
    if(element.style.opacity == null 
        || element.style.opacity == '' 
        || element.style.opacity == '1')
    {
      element.FadeState = 2;
	  setTimeout( "fade('" + eid + "')", 8000);
      return;
    }
    else
    {
      element.FadeState = -2;
    }
  }
    
  if(element.FadeState == 1 || element.FadeState == -1)
  {
    element.FadeState = element.FadeState == 1 ? -1 : 1;
    element.FadeTimeLeft = TimeToFade - element.FadeTimeLeft;
  }
  else
  {
    element.FadeState = element.FadeState == 2 ? -1 : 1;
    element.FadeTimeLeft = TimeToFade;
    setTimeout("animateFade(" + new Date().getTime() + ",'" + eid + "')", 33);
  }
}
function animateFade(lastTick, eid)
{  
  var curTick = new Date().getTime();
  var elapsedTicks = curTick - lastTick;
  
  var element = document.getElementById(eid);
 
  if(element.FadeTimeLeft <= elapsedTicks)
  {
    element.style.opacity = element.FadeState == 1 ? '1' : '0';
    element.style.filter = 'alpha(opacity = ' 
        + (element.FadeState == 1 ? '100' : '0') + ')';
    element.FadeState = element.FadeState == 1 ? 2 : -2;
	  if (element.FadeState == -2) {
		if (currentKey == slideshow_images.length-1) {
			currentKey = 0;
			showComplete = true;
		} else { currentKey++; }
		set_slideshow(currentKey);
	  	fade(eid);
	  } else { setTimeout( "fade('" + eid + "')", 5000); }
  //alert(element.FadeState);
    return;
  }
 
  element.FadeTimeLeft -= elapsedTicks;
  var newOpVal = element.FadeTimeLeft/TimeToFade;
  if(element.FadeState == 1)
    newOpVal = 1 - newOpVal;

  element.style.opacity = newOpVal;
  element.style.filter = 'alpha(opacity = ' + (newOpVal*100) + ')';
  setTimeout("animateFade(" + curTick + ",'" + eid + "')", 33);
  //alert(element.FadeState);
}

document.imageArray = new Array(slideshow_images.length);

function simplePreload (currentKey) {
	if (currentKey == 0) {
		document.imageArray[currentKey] = new Image;
		document.imageArray[currentKey].src = slideshow_images[currentKey];
	}
	var nextKey = currentKey + 1;
	document.imageArray[nextKey] = new Image;
	document.imageArray[nextKey].src = slideshow_images[nextKey];
}