var xReq = null;
function initAjaxRequest(){
	if(window.XMLHttpRequest){
		xReq = new XMLHttpRequest();
	}else if(typeof ActiveXObject != "undefined"){
		xReq = new ActiveXObject("Microsoft.XMLHTTP");
	}
}

function ie() {
	if (document.all) {
		return false; 
	} 
}
function ns(e) {
	if (document.layers||(document.getElementById&&!document.all)) {
		if (e.which==2 || e.which==3) {
			document.oncontextmenu=new Function("return false");
			return false; 
		} 
	} 
}
if (document.layers) {
	document.captureEvents(Event.MOUSEDOWN);
	document.onmousedown=ns;
} else {
	document.onmouseup=ns;
	document.oncontextmenu=ie;
}

function divImage(divI, imgP){
	divI.style.backgroundImage = "url(" + imgP + ")";
	divI.style.position = "relative";
	divI.style.top = "0";
	divI.style.left = "0";
	divI.style.width = "100%";
	divI.style.height = "100%";
}


function show_timer() {
  if(show_delay >= 0){
    show_delay--;
    if(show_delay<0 && show_param>0) {
	window.location = nextPage + "?show_param=" + show_param;
    }
    else { if(show_param>0) { window.status='Time left: '+(show_delay+1)+' s'; }}
  }
  setTimeout('show_timer()', 1000);	
}
function playSlideshow(){
	show_param = 5;
	show_delay = show_param;
	show_timer();
}

function stopSlideshow(){
	show_param = 0;
}

function getCookie(name){
	var cname = name + "=";
    	var dc = document.cookie;
    	if(dc.length > 0){
    		begin = dc.indexOf(cname);
		if(begin != -1){
          		begin += cname.length;
          		end = dc.indexOf("|", begin);
         	 	if(end == -1){
				end = dc.length;
			}
          		return unescape(dc.substring(begin, end));
        	}
      }
      return "null";
}

function setCookie(name, value){
	document.cookie = name + "=" + escape(value) + "|";
}


var dir = "";
var playId = null;
function playGallerySlideshow(){
	loadNextImage();
	playId = setTimeout("playGallerySlideshow()", 7000);
}

function stopGallerySlideshow(){
	clearTimeout(playId);	
}

function sendRequest(url, functionCall){
	initAjaxRequest();
	if(xReq){
		xReq.onreadystatechange=functionCall;
		xReq.open("GET", url, true);
		xReq.setRequestHeader("Content-Type", "application/x-www-form-urlencoded");
		xReq.send(null);
	}	
}

function getCurrImage(){
	var src = document.getElementById("image").style.backgroundImage;
	var index = src.lastIndexOf("/");
	var image = src.substring(index + 1, src.lastIndexOf(")"));
	return image;
}

function getCurrPort(){
	var src = document.getElementById("image").style.backgroundImage;
	var index = src.lastIndexOf("/");
	var port = src.substring(src.lastIndexOf("(") + 1, index);
	index = port.lastIndexOf("/");
	return port.substring(index + 1);
}
function loadNextImage(){
	var port = getCurrPort();
	var image = getCurrImage();
	var url = "list.php?dir=next&port=" + port + "&curr=" + image;
	dir = "next";
	sendRequest(url, onloadCurrImage);
}
	
function loadPrevImage(){
	var port = getCurrPort();
	var image = getCurrImage();
	var url = "list.php?dir=prev&port=" + port + "&curr=" + image;
	dir = "prev";
	sendRequest(url, onloadCurrImage);
}
	
function onloadCurrImage(){
	var ready = xReq.readyState;
	var image = document.getElementById("image");
	if(ready == 4){
		var src = xReq.responseText;
		image.style.backgroundImage = "url(" + src + ")";
	}else{
		//image.src = "Loading image ...";
	}
}

function enableNavigation(){
	var navMenu = document.getElementById("navMenu");
	navMenu.style.display="block";
	var currImage = document.getElementById("currImage");
	currImage.useMap = null;
	
}

function loadGallery(){
	enableNavigation();
	var url = "list.php?port=Gallery";
	sendRequest(url, onloadNavigator);
}

function onloadNavigator(){
	var ready = xReq.readyState;
	var currImage = document.getElementById("currImage");
	var image = document.getElementById("image");
	if(ready == 4){
		var src = xReq.responseText;
		var index = src.indexOf(";");
		var rEnd = src.substring(index+1);
		
		var src1 = src.substring(0, index);
		currImage.src = "../res/blank.gif";
		currImage.width="1000";
		currImage.height="600";
		image.style.backgroundImage = "url(" + src1 + ")";
		image.style.width=currImage.width;
		image.style.height=currImage.height;
		image.style.align="center";
	}else{
		//currImage.src = "Loading image ...";
	}
}