function $(sID) {
  return document.getElementById(sID); // thank-you, prototype.
}
addLoadListener(initCategories);
function initCategories()
{
	var categories = getElementsByClassName("tab","td",$("navTbl"));
	  for (var i = 0; i < categories.length; i++)
	  {
		attachEventListener(categories[i], "mouseover", categoryOver, false);
		attachEventListener(categories[i], "mouseout", categoryOut, false);
	  }
	  return true;
}
function categoryOver(event)
{
	if (typeof event == "undefined")
	{
		event = window.event;
	}

	var target = getEventTarget(event);
	topMenu(target,1);
}


function categoryOut(event)
{
	if (typeof event == "undefined")
	{
		event = window.event;
	}

	var target = getEventTarget(event);
	topMenu(target,0);
}

function topMenu(td,act)
{
	var tds = td.id;
	tds = tds.split("_");
	if (act == 1){
		$('td_'+tds[1]+"_center").className = "tabOver";
		$('td_'+tds[1]+"_right").className = "tabRightOver";
		$('td_'+tds[1]+"_left").className = "tabLeftOver";
		$('td_'+tds[1]+"_a").className = "topMenu_a_selected";
	}
	else {
		$('td_'+tds[1]+"_center").className = "tab";
		$('td_'+tds[1]+"_right").className = "tabSide";
		$('td_'+tds[1]+"_left").className = "tabSide";
		$('td_'+tds[1]+"_a").className = "";
	}
}

function addLoadListener(fn)
{
  if (typeof window.addEventListener != 'undefined')
  {
    window.addEventListener('load', fn, false);
  }
  else if (typeof document.addEventListener != 'undefined')
  {
    document.addEventListener('load', fn, false);
  }
  else if (typeof window.attachEvent != 'undefined')
  {
    window.attachEvent('onload', fn);
  }
  else
  {
    var oldfn = window.onload;
    if (typeof window.onload != 'function')
    {
      window.onload = fn;
    }
    else
    {
      window.onload = function()
      {
        oldfn();
        fn();
      };
    }
  }
}

function attachEventListener(target, eventType, functionRef, capture)
{
  if (typeof target.addEventListener != "undefined")
  {
    target.addEventListener(eventType, functionRef, capture);
  }
  else if (typeof target.attachEvent != "undefined")
  {
    target.attachEvent("on" + eventType, functionRef);
  }
  else
  {
    eventType = "on" + eventType;

    if (typeof target[eventType] == "function")
    {
      var oldListener = target[eventType];

      target[eventType] = function()
      {
        oldListener();

        return functionRef();
      }
    }
    else
    {
      target[eventType] = functionRef;
    }
  }

  return true;
}

function getEventTarget(event)
{
  var targetElement = null;
  if (typeof event == "undefined")
  {
	event = window.event;
  }
  if (typeof event != "undefined")
  {
    targetElement = event.target;
  }
  else
  {
	event = window.event;
    targetElement = event.srcElement;
  }

  while (targetElement.nodeType == 3 && targetElement.parentNode != null)
  {
    targetElement = targetElement.parentNode;
  }

  return targetElement;
}

function getViewportSize()
{
  var size = [0,0];

  if (typeof window.innerWidth != 'undefined')
  {
    size = [
        window.innerWidth,
        window.innerHeight
    ];
  }
  else if (typeof document.documentElement != 'undefined'
      && typeof document.documentElement.clientWidth != 'undefined'
      && document.documentElement.clientWidth != 0)
  {
    size = [
        document.documentElement.clientWidth,
        document.documentElement.clientHeight
    ];
  }
  else
  {
    size = [
        document.getElementsByTagName('body')[0].clientWidth,
        document.getElementsByTagName('body')[0].clientHeight
    ];
  }

  return size;
}

function getScrollingPosition()
{
  //array for X and Y scroll position
  var position = [0, 0];

  //if the window.pageYOffset property is supported
  if(typeof window.pageYOffset != 'undefined')
  {
    //store position values
    position = [
        window.pageXOffset,
        window.pageYOffset
    ];
  }

  //if the documentElement.scrollTop property is supported
  //and the value is greater than zero
  if(typeof document.documentElement.scrollTop != 'undefined'
    && document.documentElement.scrollTop > 0)
  {
    //store position values
    position = [
        document.documentElement.scrollLeft,
        document.documentElement.scrollTop
    ];
  }

  //if the body.scrollTop property is supported
  else if(typeof document.body.scrollTop != 'undefined')
  {
    //store position values
    position = [
        document.body.scrollLeft,
        document.body.scrollTop
    ];
  }

  //return the array
  return position;
}

function getElementsByAttribute(attribute, attributeValue)
{
  var elementArray = new Array();
  var matchedArray = new Array();

  if (document.all)
  {
    elementArray = document.all;
  }
  else
  {
    elementArray = document.getElementsByTagName("*");
  }

  for (var i = 0; i < elementArray.length; i++)
  {
    if (attribute == "class")
    {
      var pattern = new RegExp("(^| )" + attributeValue + "( |$)");

      if (elementArray[i].className.match(pattern))
      {
        matchedArray[matchedArray.length] = elementArray[i];
      }
    }
    else if (attribute == "for")
    {
      if (elementArray[i].getAttribute("htmlFor") || elementArray[i].getAttribute("for"))
      {
        if (elementArray[i].htmlFor == attributeValue)
        {
          matchedArray[matchedArray.length] = elementArray[i];
        }
      }
    }
    else if (elementArray[i].getAttribute(attribute) == attributeValue)
    {
      matchedArray[matchedArray.length] = elementArray[i];
    }
  }

  return matchedArray;
}