var fullwidth;
var offset=836;
var element_width=176;
var between_width=33;
var delay=1100;
var pos=1;
var elements_shown=4;

function show_prev()
{
	if(pos>1)
	{
		pos--;

		$("#frame #gallery_list").animate({left: -(pos-1)*offset}, delay);

		if(pos==1)	
			$("#prev").css("background-position", "left bottom");

		$("#next").css("background-position", "left top");
	}

	return false;
}
function show_next()
{
	if(fullwidth/(pos*offset)>=1)
	{
		if(fullwidth-pos*offset<offset && fullwidth>=pos*offset)
		{
			$("#frame #gallery_list").animate({left: -(pos-1)*offset-(fullwidth-pos*offset)-between_width}, delay);
		}
		else if(fullwidth>=pos*offset)
		{
			$("#frame #gallery_list").animate({left: -pos*offset}, delay);
		}

		pos++;

		if(fullwidth/(pos*offset)<1)
			$("#next").css("background-position", "left bottom");
		
		$("#prev").css("background-position", "left top");
	}

	return false;
}
function load_karusel()
{
	var elements_count=$("#gallery_list img").length;
	fullwidth=elements_count*(element_width+between_width)-between_width;

	$("#gallery_list").css("width", fullwidth+"px");
	$($("#gallery_list img").get(elements_count-1)).css("margin-right", "0");

	if(elements_count>elements_shown)
	{
		$('<a href="#" id="prev"><span>назад</span></a><a href="#" id="next"><span>вперёд</span></a>').appendTo("#gallery");
		$("#prev").click(show_prev);
		$("#next").click(show_next);
	}
}
function init()
{
	load_karusel();
}
$(document).ready(init);