// JavaScript Document

// Improved Unobtrusive Javascript Image Rollover v1.0
// By Christian Watson: http://www.smileycat.com
// Based on a script by Chris Nott: http://www.dithered.com/javascript/rollovers/index.html
// license: http://creativecommons.org/licenses/by/1.0/

function isDefined(property) {
  return (typeof property != 'undefined');
}

var rolloverInitialized = false;
function rolloverInit() {

   if (!rolloverInitialized && isDefined(document.images)) {

      var bodyId = document.body.id;    // ID of the BODY tag
      
	  
	 
		  // get all images (including all <input type="image">s)
		  // use getElementsByTagName() if supported
		  var images = new Array();
		  if (isDefined(document.getElementsByTagName)) {
			 images = document.getElementsByTagName('img');
			 var inputs = document.getElementsByTagName('input');
			 for (var i = 0; i < inputs.length; i++) {
				if (inputs[i].type == 'image') {
				   images[images.length] = inputs[i];
				}
			 }
		  }
		  
		  // otherwise, use document.images and document.forms collections
		  
		  // remove if not supporting IE4, Opera 4-5
		  else {
			 images = document.images;
			 inputs = new Array();
			 for (var formIndex = 0; formIndex < document.forms.length; formIndex++) {
				for (var elementIndex = 0; elementIndex < document.forms.elements.length; elementIndex++) {
				   if (isDefined(document.forms.elements[i].src)) {
					  inputs[inputs.length] = document.forms.elements[i];
				   }
				}
			 }
		  }
		  
		  // get all images with '_off.' in src value excepting the one that is for the BODY
	
		  for (var i = 0; i < images.length; i++) {
			 if (images[i].src.indexOf('_off.') != -1) {
	
				// check for BODY image, and turn it 'on' if found
				if (images[i].src.indexOf(bodyId) != -1)
				   images[i].src = images[i].src.replace(/_off\./, '_on.');
			
				else {
	
				var image = images[i];
				
				
				// store the over state filename in a property of the image object
				image.overImage = new Image();
				image.overImage.src = image.src;
				
				// store the off state filename in a property of the image object
				image.offImage = new Image();
				image.offImage.src = image.src;
				
				// store the on state filename in a property of the image object
				// (also preloads the on state image)
				image.onImage = new Image();
				image.onImage.imageElement = image;
				
				
				// add onmouseover and onmouseout event handlers once the on state image has loaded
				
				// Safari's onload is screwed up for off-screen images; temporary fix
				if (navigator.userAgent.toLowerCase().indexOf('safari') != - 1) {
				     image.onmouseover = function() {
					  this.src = this.overImage.src;
				   };
				   image.onmouseout = function() {
					  this.src = this.offImage.src;
				   };
				}
				else {
				   image.onImage.onload = function() {
					  this.imageElement.onmouseover = function() {
						 this.src = this.overImage.src;
					  };
					  this.imageElement.onmouseout = function() {
						 this.src = this.offImage.src;
					  };
				   };
				}
				
		
				
				// set src of on state image after defining onload event handler
				// so cached images (that load instantly in IE) will trigger onload
				image.onImage.src = image.src.replace(/_off\./, '_on.');
				image.overImage.src = image.src.replace(/_off\./, '_over.');
				
	
			   }
			 }
		  }
	   }

   rolloverInitialized = true;
}

// call rolloverInit when document finishes loading
if (isDefined(window.addEventListener)) {
   window.addEventListener('load', rolloverInit, false);
}
else if (isDefined(window.attachEvent)) {
   window.attachEvent('onload', rolloverInit);
}