//Triger function when page is loaded
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 detachEventListener(target, eventType, functionRef, capture)
{
  if (typeof target.removeEventListener != "undefined")
  {
    target.removeEventListener(eventType, functionRef, capture);
  }
  else if (typeof target.detachEvent != "undefined")
  {
    target.detachEvent("on" + eventType, functionRef);
  }
  else
  {
    target["on" + eventType] = null;
  }

  return true;
}

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;
}

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

  var scrollingPosition = getScrollingPosition();
  var cursorPosition = [0, 0];

  if (typeof event.pageX != "undefined" && typeof event.x != "undefined")
  {
    cursorPosition[0] = event.pageX;
    cursorPosition[1] = event.pageY;
  }
  else
  {
    cursorPosition[0] = event.clientX + scrollingPosition[0];
    cursorPosition[1] = event.clientY + scrollingPosition[1];
  }

  var paragraph = document.getElementsByTagName("p")[0];

  paragraph.replaceChild(document.createTextNode("Your mouse is currently located at: " + cursorPosition[0] + "," + cursorPosition[1]), paragraph.firstChild);

  return true;
}

function getEventTarget(event)
{
  var targetElement = null;

  if (typeof event.target != "undefined")
  {
    targetElement = event.target;
  }
  else
  {
    targetElement = event.srcElement;
  }

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

  return targetElement;
}

//return all elements with provided classname
function getElementsByClassName (className) {
  var all = document.all ? document.all :
    document.getElementsByTagName('*');
  var elements = new Array();
  for (var e = 0; e < all.length; e++)
  {
    if (all[e].className == className)
      elements[elements.length] = all[e];
  }
  return elements;
}

//return all png images
function getAllPNGimages()
{
	var all = document.all ? document.all :
    document.getElementsByTagName('img');
  	var elements = new Array();
  	var pattern = /.png$/;
  
  
  	for (var i = 0; i < all.length; i++)
  	{
		if (pattern.test(all[i].src))
      		elements[elements.length] = all[i];
  	}
  	return elements;
}


//Get position of element
function getPosition(theElement)
{
  var positionX = 0;
  var positionY = 0;

  while (theElement != null)
  {
    positionX += theElement.offsetLeft;
    positionY += theElement.offsetTop;
    theElement = theElement.offsetParent;
  }
  
  return [positionX, positionY];
}

//Stop default action
function stopDefaultAction(event)
{
  event.returnValue = false;

  if (typeof event.preventDefault != "undefined")
  {
    event.preventDefault();
  }

  return true; 
}

function stopEvent(event)
{
  if (typeof event.stopPropagation != "undefined")
  {
    event.stopPropagation();
  }
  else
  {
    event.cancelBubble = true;
  }

  return true;
}

function identifyBrowser()
{
  var agent = navigator.userAgent.toLowerCase();

  if (typeof navigator.vendor != "undefined" && navigator.vendor == "KDE" && typeof window.sidebar != "undefined")
  {
    return "kde";
  }
  else if (typeof window.opera != "undefined")
  {
    var version = parseFloat(agent.replace(/.*opera[\/ ]([^ $]+).*/, "$1"));

    if (version >= 7)
    {
      return "opera7";
    }
    else if (version >= 5)
    {
      return "opera5";
    }

    return false;
  }
  else if (typeof document.all != "undefined")
  {
    if (typeof document.getElementById != "undefined")
    {
      var browser = agent.replace(/.*ms(ie[\/ ][^ $]+).*/, "$1").replace(/ /, "");

      if (typeof document.uniqueID != "undefined")
      {
        if (browser.indexOf("5.5") != -1)
        {
          return browser.replace(/(.*5\.5).*/, "$1");
        }
        else
        {
          return browser.replace(/(.*)\..*/, "$1");
        }
      }
      else
      {
        return "ie5mac";
      }
    }

    return false;
  }
  else if (typeof document.getElementById != "undefined")
  {
    if (navigator.vendor.indexOf("Apple Computer, Inc.") != -1)
    {
      if (typeof window.XMLHttpRequest != "undefined")
      {
        return "safari1.2";
      }

      return "safari1";
    }
    else if (agent.indexOf("gecko") != -1)
    {
      return "mozilla";
    }
  }

  return false;
}
function retrieveComputedStyle(element, styleProperty)
{
	var computedStyle = null;
	if (typeof element.currentStyle != "undefined")
	{
		computedStyle = element.currentStyle;
	}
	else
	{
		computedStyle = document.defaultView.getComputedStyle(element, null);
	}
	return computedStyle[styleProperty];
}