/*
divId: id of the block to be expanded
name: global javascript name of this object (This is a super-lame hack, please fix)
height: collapsed height
time: time (in milliseconds) that the expansion should take
part: the number of partial expansions which add up to the complete expansion
imgId: id of an image to be swapped during expansion/collapsing
cImage: image data for the collapsed image
eImage: image data for the expanded image
*/
function Xpander( divId, name, height, time, part, imgId, cImage, eImage)
{
  this.Id = divId;
  this.name = name;
  this.defaultHeight = height;
  this.defaultTime = time;
  this.partitions = part;
  this.imageId = imgId;
  this.collapsedImage = cImage;
  this.expandedImage = eImage;

  this.elem = document.getElementById( this.Id);
}

Xr = Xpander.prototype;

Xr.expandRecursion = function()
{
  diff = this.elem.scrollHeight - this.elem.offsetHeight;
  if (diff > 0)
  {
    //alert( "recurse, diff :"+diff+", this.partSize: "+Math.floor(this.partSize)+", height: "+this.elem.style.height+", off: "+this.elem.offsetHeight+", scroll: "+this.elem.scrollHeight);
    if (diff >= this.partSize)
    {
      this.elem.style.height = this.elem.offsetHeight + Math.floor(this.partSize) + "px";
    }
    else
    {
      this.elem.style.height = this.elem.scrollHeight;
    }
    setTimeout( this.name+".expandRecursion()", Math.floor(this.defaultTime/(this.partitions + 1)));
  }
}

Xr.expand = function()
{
  origDiff = this.elem.scrollHeight - this.elem.offsetHeight;
  this.partSize = Math.floor( origDiff/this.partitions);

  this.expandRecursion();
  if (this.expandedImage != null)
    this.setImage( this.expandedImage);
}

Xr.collapse = function()
{
  elem = this.elem;
  if (elem.offsetHeight >= elem.scrollHeight)
  {
    elem.style.height = this.defaultHeight;
    elem.style.overflow = "hidden";    
    if (this.collapsedImage != null)
      this.setImage( this.collapsedImage);
  }
}

Xr.isCollapsed = function()
{
    return (this.elem.style.height == this.defaultHeight);
}

Xr.needMoreButton = function()
{
    if (this.isCollapsed())
    {
	return this._needMoreButton();
    }
    else
    {
	this.collapse();
	nmb = this._needMoreButton();
	if (nmb) { this.expand(); }
	return nmb;
    }
}
Xr._needMoreButton = function()
{
    return (this.elem.scrollHeight > this.elem.offsetHeight);
}

Xr.displayMoreButton = function()
{
    if (!this.needMoreButton())
    {
	moreButton = document.getElementById( this.imageId);
	moreButton.style.display = 'none';
    }
}


Xr.toggle = function()
{
  if (this.elem.offsetHeight >= this.elem.scrollHeight)
  {
    this.collapse();
  }
  else
  {
    this.expand();
  }  
}

Xr.setImage = function( image)
{
  imageElem = document.getElementById( this.imageId);
  imageElem.src = image.src; 
  imageElem.alt = image.alt; 
}


///////////////////////////////
// For Backwards Compatibility

var sDiv="";
var inEm = 1;

btnMore0 = new Image(); btnMore0.src = "/images/buttons/btnMore.gif"; btnMore0.alt = "more";
btnMore1 = new Image(); btnMore1.src = "/images/buttons/btnHide.gif"; btnMore1.alt = "hide";

	
function xpnd(x, button)
{
	sDiv = x;
	
	if (sDiv.offsetHeight >= sDiv.scrollHeight)
	{
		sDiv.style.height="1px";
		sDiv.style.overflow="hidden";
		
		flipImg(button, 0);
	}
	else
	{
		xpndAn();
		
		flipImg(button, 1);
	}

}

function xpndAn()
{
	if (sDiv.offsetHeight < sDiv.scrollHeight)
	{
		sDiv.style.height= inEm + "em";
		inEm += 2.5;
		setTimeout("xpndAn()","10");
	}
	else
	{
		inEm = 1;
	}
}


function flipImg(imgName, mode) 
{
	document[imgName].src = eval(imgName + mode + ".src");
	document[imgName].alt = eval(imgName + mode + ".alt");
}


//----------------------------
// ImageData
//----------------------------
function ImageData( src, alt)
{
    this.src = src;
    this.alt = alt;
}
ID = ImageData.prototype;

ID.toString = function()
{
    return "{ "+this.src+", "+this.alt+"}";
}