var timerlen = 5;
var slideAniLen = 500;

var timerID = new Array();
var startTime = new Array();
var obj = new Array();
var endHeight = new Array();
var moving = new Array();
var dir = new Array();

function slidedown(objname){
  if(moving[objname])
    return;
 
  if($(objname).style.display != "none")
    return; // cannot slide down something that is already visible
 
  moving[objname] = true;
  dir[objname] = "down";
  startslide(objname);
}
 
function slideup(objname){
  if(moving[objname])
    return;
 
  if($(objname).style.display == "none")
    return; // cannot slide up something that is already hidden
 
  moving[objname] = true;
  dir[objname] = "up";
  startslide(objname);
}

function startslide(objname){
  obj[objname] = $(objname);
 
  endHeight[objname] = parseInt(obj[objname].style.height);
  startTime[objname] = (new Date()).getTime();
 
  if(dir[objname] == "down"){
    obj[objname].style.height = "1px";
  }
 
  obj[objname].style.display = "block";
 
  timerID[objname] = setInterval('slidetick(\'' + objname + '\');',timerlen);
}


function slidetick(objname){
  var elapsed = (new Date()).getTime() - startTime[objname];
 
  if (elapsed > slideAniLen)
    endSlide(objname)
  else {
    var d =Math.round(elapsed / slideAniLen * endHeight[objname]);
    if(dir[objname] == "up")
      d = endHeight[objname] - d;
 
    obj[objname].style.height = d + "px";
  }
 
  return;
}

function endSlide(objname){
  clearInterval(timerID[objname]);
 
  if(dir[objname] == "up")
    obj[objname].style.display = "none";
 
  obj[objname].style.height = endHeight[objname] + "px";
 
  delete(moving[objname]);
  delete(timerID[objname]);
  delete(startTime[objname]);
  delete(endHeight[objname]);
  delete(obj[objname]);
  delete(dir[objname]);
 
  return;
}

function toggleSlide(objname){
  if($(objname).style.display == "none"){
    // div is hidden, so let's slide down
    slidedown(objname);
  }else{
    // div is not hidden, so slide up
    slideup(objname);
  }
}

function toggleDisplay(objname){
	$(objname).style.display = (($(objname).style.display == "none")?"block":"none");
	if ((isdefined(objname+'Edit')) && ($(objname).style.display == "none")) {
		$(objname+'Edit').style.display = "none";
	}
}

function toggleDisplayAndImage(objname){
	$(objname).style.display = (($(objname).style.display == "none")?"block":"none");
	if ((isdefined(objname+'Edit')) && ($(objname).style.display == "none")) {
		$(objname+'Edit').style.display = "none";
	}
	
	existingImageSrc = $(objname+'But').src;
	existingImageAlt = $(objname+'But').alt;
	srcImageLoc = existingImageSrc.lastIndexOf('/');
	srcImage= existingImageSrc.substr(srcImageLoc+1, 11);
	newSrcImage = ((srcImage == "but_min.gif")?"but_max.gif":"but_min.gif");
	newAltImage = ((existingImageAlt == "Minimise")?"Maximise":"Minimise");
	newImageSrc = existingImageSrc.substr(0, (srcImageLoc+1)) + newSrcImage;
	$(objname+'But').src = newImageSrc;
	$(objname+'But').alt = newAltImage;
}