// JavaScript Document
function createRequestObject() {

   var req;

   if(window.XMLHttpRequest){
      // Firefox, Safari, Opera...
      req = new XMLHttpRequest();
   } else if(window.ActiveXObject) {
      // Internet Explorer 5+
      req = new ActiveXObject("Microsoft.XMLHTTP");
   } else {
      // There is an error creating the object,
      // just as an old browser is being used.
      alert('Problem creating the XMLHttpRequest object');
   }

   return req;

} 

// Make the XMLHttpRequest object
var http = createRequestObject(); 

function sendRequest(varString) {

   // Open PHP script for requests
   //http.abort;
   http.open('post', 'ajax/get_imgs.php');
   http.onreadystatechange = handleResponse; 
   http.setRequestHeader('Content-Type', 'application/x-www-form-urlencoded');
   http.send(varString);
   

}
function handleResponse() {
	
	
//function to preload new batch of images
function fPreloadImg(){

var imgItems = document.getElementById("thumbPrev").getElementsByTagName("img");

iImage = new Array();

	for (var i=0; i<imgItems.length; i++) {
		
		var lrgImg = imgItems[i].src.replace('thmb_', '');
		 iImage[i] =  new Image();
		 iImage[i].src = lrgImg;
				
	}


}

   if(http.readyState == 4 && http.status == 200){

      // Text returned FROM the PHP script
      var response = http.responseText;

      if(response) {
		  
         // UPDATE ajaxTest content
         document.getElementById("thumbPrev").innerHTML = response;
		// alert("WORKING");
		 vSmImage = document.getElementById('imgStart').src;
		 
		 vLrgImgSrc = vSmImage.replace('thmb_', '');
		 
		 fLoadImage(vLrgImgSrc);
		 
		 fPreloadImg();

      }

   }

}