function main_menu()
{
	var html_main_menu_container=$("#main_menu_container");
	var html_main_menu_sliding_panel=$("#main_menu_sliding_panel");
	var html_main_menu_static_panel=$("#main_menu_static_panel");
	
	var the_window=$(window);
	
	var that=this;
	
	var is_opened;
	
	var clicked_link;
	
	function init()
	{
		// inizializza il pannello nello stato grafico "chiuso"
		//html_main_menu_sliding_panel.css('height','232px');
		is_opened=false;
		
		$('#main_menu_items li:nth-child(odd) a').css("background-image","url(./assets/main_menu_buttons-left.png)");
		$('#main_menu_items li:nth-child(even) a').css("background-image","url(./assets/main_menu_buttons-right.png)");
		
		$('#main_menu_items > li > a').click(function(event_obj){
			// if($(this).hasClass("active")==false)
			// {
				// $('#main_menu_items li a').removeClass("active");
				// $(this).addClass("active");
			// }
			event_obj.preventDefault();
			clicked_link=$(this);
			
			if(is_opened!=false)
			{
				var main_menu_open_event=jQuery.Event("main_menu_open");
				html_main_menu_container.trigger(main_menu_open_event);
				
				html_main_menu_sliding_panel.stop(true,true).animate({"height": "232px"},'fast','swing',jQuery.proxy(function(){
					window.location=clicked_link.attr("href");
				},that));
				is_opened=false;
			}
			else
			{
				window.location=clicked_link.attr("href");
			}
		});
		
		// mantieni la sua posizione al centro on browser resizing (usando jQuery.proxy per cambiare il contesto di this all'interno dell'handler)
		the_window.bind('resize',jQuery.proxy(function(){
				html_main_menu_container.css('left', (the_window.width() - html_main_menu_container.width())/2);
			},that)
		);
		
		the_window.resize();
		
		html_main_menu_container.fadeIn(800,function(){
			html_main_menu_static_panel.bind('click',jQuery.proxy(collapse,that));
		});
	}
	
	function collapse()
	{
		var main_menu_open_event=jQuery.Event("main_menu_open");
	
		html_main_menu_static_panel.trigger(main_menu_open_event);
		
		//console.log('collapse: '+this);
		if(is_opened==false)
		{
			open();
		}
		else
		{
			close();
		}
	}
	
	function open()
	{
		if(is_opened!=true)
		{
			html_main_menu_sliding_panel.stop(true,true).animate({"height": "466px"},500,'swing');
			is_opened=true;
		}
		else return;
	}
	
	function close()
	{
		if(is_opened!=false)
		{
			html_main_menu_sliding_panel.stop(true,true).animate({"height": "232px"},500,'swing');
			is_opened=false;
		}
		else return;
	}
	
	init();
}


function dimmer()
{
	var html_dimmer=$("#dimmer");
	
	var is_visible=false;
	
    html_dimmer.css("height", $(document).height());
	
	$(window).bind("resize", function(){
		html_dimmer.css("height", $(window).height());
		});
		
	function dimIn()
	{
		if(is_visible==false)
		{
			html_dimmer.fadeIn();
			is_visible=true;
		}
		else return;
	}
	
	function dimOut()
	{
		if(is_visible==true)
		{
			html_dimmer.fadeOut();
			is_visible=false;
		}
		else return;
	}
	
	function dimToggle()
	{
		//console.log('dimToggle: ');
		if(is_visible==false)
		{
			dimIn();
		}
		else
		{
			dimOut();
		}
	}
	
	$("body").bind("main_menu_open",dimToggle);
}