var ur_current = -1;
var ur_active = false;
var ur_obj;
var ur_queue = new Array();
var ur_queue_size = 0;
var ur_current_queue_element = 0;
var ur_used = false;

function ur_next(is_queue) {
	if (!is_queue) ur_used = true;
	if (ur_active && !is_queue) {
		ur_queue[ur_queue_size++] = "ur_next(true);";
		
	} else {
		ur_obj = document.getElementById('ur_layer');
		ur_active = true;
		
		if (document.getElementById('ur_p'+(ur_current+1)))
			ur_move_next(1, 1);
		else 
			ur_move_next(1, -ur_current);
	}
}

function ur_move_next(i, dif) {
	ur_obj.style.top = ((-ur_current*171)-(i*(171*dif)/20))+"px";
	
	if (i != 20) window.setTimeout("ur_move_next("+(i+1)+", "+dif+");", 20);
	else {
		ur_current += dif;
		
		if (ur_queue_size == ur_current_queue_element) {
			ur_active = false;
			ur_queue = new Array();
			ur_queue_size = 0;
			ur_current_queue_element = 0;
		} else {
			window.setTimeout(ur_queue[ur_current_queue_element++], 20);
		}
	}
}

function ur_prev(is_queue) {
	if (!is_queue) ur_used = true;
	if (ur_active && !is_queue) {
		ur_queue[ur_queue_size++] = "ur_prev(true);";
		
	} else {

		ur_obj = document.getElementById('ur_layer');
		ur_active = true;
		
		if (document.getElementById('ur_p'+(ur_current-1)))
			ur_move_prev(1, 1);
		else {
			var i = 0;
			while(document.getElementById('ur_p'+(i++)));
			ur_move_prev(1, -(i-2));
		}
	}
}

function ur_move_prev(i, dif) {
	
	ur_obj.style.top = ((-ur_current*171)+(i*(171*dif)/20))+"px";
	
	if (i != 20) window.setTimeout("ur_move_prev("+(i+1)+", "+dif+");", 20);
	else {
		ur_current -= dif;
		
		if (ur_queue_size == ur_current_queue_element) {
			ur_active = false;
			ur_queue = new Array();
			ur_queue_size = 0;
			ur_current_queue_element = 0;
		} else {
			window.setTimeout(ur_queue[ur_current_queue_element++], 20);
		}
	}
}

function ur_in(obj) {
	obj.style.backgroundColor = "#0064ff";
}

function ur_out(obj) {
	obj.style.backgroundColor = "#151515";
}

function ur_init() {
	if (ur_active == false && ur_current != -1 && ur_used == false) ur_next(false);
	if (ur_current == -1) ur_current = 0;
	ur_used = false;
	window.setTimeout("ur_init();", 5000);
}

ur_init();