/* ad rotation */
var allAds = new Array(
					   '<strong>THE NEW DESIRES HOTELS<br>COLLECTION ON THE GDS</strong>',
					   '<div class="menuButton"><a href="offers.php">CLICK HERE FOR SPECIAL OFFERS</a></div>'
					   );

var curAd = 1;
var maxAd = allAds.length;

var opacityDecrease_ad = false;
var curOpacity_ad = 100;

var changeDelay_ad = 5000;
var timerDelay_ad = 25;
var fadeDelta_ad = 4;
var initialDelay_ad = 2000;
var adID = "lblAd";


/* end ad rotation */


/* menu background image */
var opacityDecrease = false;
var curOpacity = 100;
var curImage = 1;
var maxImage = 14;

var changeDelay = 5000;
var imageWidth = 1000;
var imageHeight = 517;
var timerDelay = 25;
var fadeDelta = 4;
var imageID = "mainImage";

var preloadedImages = new Array();

var imagePrefix = "images/menuBackgrounds/bg";
/* end menu background image */


/* shared functions */
function init(startImage) {   
	curImage = startImage;
	opacityDecrease = true;
	curOpacity = 100;
	setTimeout("fadeTimer()",changeDelay);
	preloadAll();
	
	initAd();
}


function setOpacity(obj, opacity) {
  if (obj) {
	  obj.style.filter = "alpha(opacity:"+opacity+")"; 
	  obj.style.KHTMLOpacity = opacity/100;
	  obj.style.MozOpacity = opacity/100;
	  obj.style.opacity = opacity/100;
  }
}
/* end shared functions */


/* ad rotation */
function initAd() {
	opacityDecrease_ad = true;
	curOpacity_ad = 100;
	setTimeout("fadeTimer_ad()",changeDelay_ad + initialDelay_ad);
}

function fadeTimer_ad() {
	if (opacityDecrease_ad)
		curOpacity_ad-=fadeDelta_ad;
	else
		curOpacity_ad+=fadeDelta_ad;
		
	if (curOpacity_ad < 0)
		curOpacity_ad = 0;
	else if (curOpacity_ad > 100)
		curOpacity_ad = 100;
	  
	var fadeLbl = document.getElementById(adID);
	  
	setOpacity(fadeLbl,curOpacity_ad);
	
	if (curOpacity_ad == 0 && opacityDecrease_ad == true) {
		opacityDecrease_ad = false;
		curAd++;
		if (curAd > maxAd)
			curAd = 1;
		fadeLbl.innerHTML = allAds[curAd-1];
		setTimeout("fadeTimer_ad()",timerDelay_ad);
	} else if (curOpacity_ad == 100 && opacityDecrease_ad == false) {
		setTimeout("fadeTimer_ad()",changeDelay_ad);
		opacityDecrease_ad = true;
	} else {
		setTimeout("fadeTimer_ad()",timerDelay_ad);    
	}
}
/* end ad rotation */



/* menu background */
function doPreload(num) {
	preloadedImages[num] = new Image(imageWidth,imageHeight);
	preloadedImages[num].src = imagePrefix + num + ".jpg";
}

function preloadAll() {
	for (var i=1; i<= maxImage; i++) {
		doPreload(i);
	}
}

function fadeTimer() {
	if (opacityDecrease)
		curOpacity-=fadeDelta;
	else
		curOpacity+=fadeDelta;
		
	if (curOpacity < 0)
		curOpacity = 0;
	else if (curOpacity > 100)
		curOpacity = 100;
	  
	var fadeImage = document.getElementById(imageID);
	  
	setOpacity(fadeImage,curOpacity);
	
	if (curOpacity == 0 && opacityDecrease == true) {
		opacityDecrease = false;
		curImage++;
		if (curImage > maxImage)
			curImage = 1;
		fadeImage.src= preloadedImages[curImage].src;
		setTimeout("fadeTimer()",timerDelay);
	} else if (curOpacity == 100 && opacityDecrease == false) {
		setTimeout("fadeTimer()",changeDelay);
		opacityDecrease = true;
	} else {
		setTimeout("fadeTimer()",timerDelay);    
	}
}
/* end menu background */