$(function() {
var $ac_background	= $('#ac_background'),
$ac_bgimage		= $ac_background.find('.ac_bgimage'),
$ac_loading		= $ac_background.find('.ac_loading'),

$ac_content		= $('#ac_content'),
$title			= $ac_content.find('h1'),
$menu			= $ac_content.find('.ac_menu'),
$mainNav		= $menu.find('ul:first'),
$menuItems		= $mainNav.children('li'),
totalItems		= $menuItems.length,
$ItemImages		= new Array();

/* 
for this menu, we will preload all the images. 
let's add all the image sources to an array,
including the bg image
*/
$menuItems.each(function(i) {
$ItemImages.push($(this).children('a:first').attr('href'));
});
$ItemImages.push($ac_bgimage.attr('src'));


var Menu 			= (function(){
var init				= function() {
loadPage();
initWindowEvent();
},
loadPage			= function() {
/*
1- loads the bg image and all the item images;
2- shows the bg image;
3- shows / slides out the menu;
4- shows the menu items;
5- initializes the menu items events
*/
$ac_loading.show();//show loading status image
$.when(loadImages()).done(function(){
$.when(showBGImage()).done(function(){
//hide the loading status image
$ac_loading.hide();
$.when(slideOutMenu()).done(function(){
$.when(toggleMenuItems('up')).done(function(){
initEventsSubMenu();
});
});
});
});
},
showBGImage			= function() {
return $.Deferred(
function(dfd) {
//adjusts the dimensions of the image to fit the screen
adjustImageSize($ac_bgimage);
$ac_bgimage.fadeIn(1000, dfd.resolve);
}
).promise();
},
slideOutMenu		= function() {
/* calculate new width for the menu */
var new_w	= $(window).width() - $title.outerWidth(true);
if (new_w < 950 - $title.outerWidth(true))
new_w = 950 - $title.outerWidth(true);
return $.Deferred(
function(dfd) {
//slides out the menu
$menu.stop()
.animate({
width	: new_w + 'px'
}, 700, dfd.resolve);
}
).promise();
},
/* shows / hides the menu items */
toggleMenuItems		= function(dir) {
return $.Deferred(
function(dfd) {
/*
slides in / out the items. 
different animation time for each one.
*/
$menuItems.each(function(i) {
var $el_title	= $(this).children('a:first'),
marginTop, opacity, easing;
if(dir === 'up'){
marginTop	= '0px';
opacity		= 1;
easing		= 'easeOutBack';
}
else if(dir === 'down'){
marginTop	= '60px';
opacity		= 0;
easing		= 'easeInBack';
}
$el_title.stop()
.animate({
marginTop	: marginTop,
opacity		: opacity
}, 200 + i * 200 , easing, function(){
if(i === totalItems - 1)
dfd.resolve();
});
});
}
).promise();
},
initEventsSubMenu	= function() {
$menuItems.each(function(i) {
var $item		= $(this), // the <li>
$el_title	= $item.children('a:first'),
el_image	= $el_title.attr('href'),
$sub_menu	= $item.find('.ac_subitem'),
$ac_close	= $sub_menu.find('.ac_close');

/* user clicks one item : appetizers | main course | desserts | wines | specials */
$el_title.bind('click.Menu', function(e) {
$.when(toggleMenuItems('down')).done(function(){
openSubMenu($item, $sub_menu, el_image);
});
return false;
});
/* closes the submenu */
$ac_close.bind('click.Menu', function(e) {
closeSubMenu($sub_menu);
return false;
});
});
},
openSubMenu			= function($item, $sub_menu, el_image) {
$sub_menu.stop()
.animate({
height		: '500px',
marginTop	: '-250px'
}, 400, function() {
//the bg image changes
showItemImage(el_image);
});
},
/* changes the background image */
showItemImage		= function(source) {
//if its the current one return
if($ac_bgimage.attr('src') === source)
return false;

var $itemImage = $('<img src="'+source+'" alt="Background" class="ac_bgimage"/>');
$itemImage.insertBefore($ac_bgimage);
adjustImageSize($itemImage);
$ac_bgimage.fadeOut(1500, function() {
$(this).remove();
$ac_bgimage = $itemImage;
});
$itemImage.fadeIn(1500);
},
closeSubMenu		= function($sub_menu) {
$sub_menu.stop()
.animate({
height		: '0px',
marginTop	: '0px'
}, 400, function() {
//show items
toggleMenuItems('up');
});
},
/*
on window resize, ajust the bg image dimentions,
and recalculate the menus width
*/
initWindowEvent		= function() {
/* on window resize set the width for the menu */
$(window).bind('resize.Menu' , function(e) {
adjustImageSize($ac_bgimage);
/* calculate new width for the menu */
var new_w	= $(window).width() - $title.outerWidth(true);
if (new_w < 950 - $title.outerWidth(true))
new_w = 950 - $title.outerWidth(true);
$menu.css('width', new_w + 'px');
});
},
/* makes an image "fullscreen" and centered */
adjustImageSize		= function($img) {
var w_w	= $(window).width(),
w_h	= $(window).height(),
r_w	= w_h / w_w,
i_w	= $img.width(),
i_h	= $img.height(),
r_i	= i_h / i_w,
new_w,new_h,
new_left,new_top;

if(r_w > r_i){
new_h	= w_h;
new_w	= w_h / r_i;
}
else{
new_h	= w_w * r_i;
new_w	= w_w;
}

$img.css({
width	: new_w + 'px',
height	: new_h + 'px',
left	: (w_w - new_w) / 2 + 'px',
top		: (w_h - new_h) / 2 + 'px'
});
},
/* preloads a set of images */
loadImages			= function() {
return $.Deferred(
function(dfd) {
var total_images 	= $ItemImages.length,
loaded			= 0;
for(var i = 0; i < total_images; ++i){
$('<img/>').load(function() {
++loaded;
if(loaded === total_images)
dfd.resolve();
}).attr('src' , $ItemImages[i]);
}
}
).promise();
};

return {
init : init
};
})();

/*
call the init method of Menu
*/
Menu.init();
});