//Cookie
function get_cookie(name) {
	var dc = document.cookie; 
	var prefix = name + "="; 
	var begin = dc.indexOf("; " + prefix); 
	if (begin == -1) {
		begin = dc.indexOf(prefix); 
		if (begin != 0) return null; 
	} else begin += 2; 
	var end = document.cookie.indexOf(";", begin); 
	if (end == -1) end = dc.length; 
	return unescape(dc.substring(begin + prefix.length, end)); 
}
function set_cookie(name, value, days) {
	var exp = null;
	if (days != null) {
		exp = new Date();
		exp.setTime(exp.getTime() + (1000 * 60 * 24 * days));
	}
	sss = name + "=" + escape(value) + "; path=/" +	((exp == null) ? "" : "; expires=" + exp.toGMTString());
	//alert (sss);
	document.cookie = sss;
}
function del_cookie(name) {
	if (get_cookie(name)) document.cookie=name+"=; expires=Thu, 01-Jan-70 00:00:01 GMT";
}


var lay_ie = document.all?1:0;
var lay_dom = document.getElementById;
var lay_jedn = document.layers? "" : "px";
var lay_shake = 16; // dzielne przez 8

var cookie_newsletter = get_cookie("newsletter");

function layer_dombody () {
	return (document.compatMode && document.compatMode != "BackCompat") ? document.documentElement : document.body;
}


// Określenie wymiaru okna przeglądarki
if (self.innerHeight) {    // all except Explorer
	var windowWidth = self.innerWidth;
	var windowHeight = self.innerHeight;
} else if (document.documentElement && document.documentElement.clientHeight) { // Explorer 6 Strict Mode
	var windowWidth = document.documentElement.clientWidth;
	var windowHeight = document.documentElement.clientHeight;
} else if (document.body) { // other Explorers
	var windowWidth = document.body.clientWidth;
	var windowHeight = document.body.clientHeight;
}

function layer_init () {
	if (!lay_dom && !lay_ie) return;
	objlayer = (lay_dom)?document.getElementById ("layer_top").style : lay_ie? document.all.layer_top : document.layer_top;

	scroll_top = (lay_ie)? layer_dombody ().scrollTop : window.pageYOffset;

	objlayer.left = windowWidth / 2 - 230 + lay_jedn; // 230 to 460 / 2 - szerokość odczytane z index.css: #layer_top.width
	
	objlayer.top = scroll_top - 250 + lay_jedn;
	objlayer.visibility = (lay_dom||lay_ie)? "visible" : "show";
	objlayer.display = "block";
	time_layer = setInterval ("layer_top ()", 50);
}

function layer_top () {
	scroll_top = (lay_ie) ? layer_dombody ().scrollTop : window.pageYOffset;
	if (parseInt (objlayer.top) < (windowHeight / 2 - 173) + scroll_top) { // 173 to 345 / 2 - wysokość layera z index.css: #layer_top.height
		objlayer.top = parseInt (objlayer.top) + 40 + lay_jedn;
	} else {
		clearInterval (time_layer);
		time_shake = setInterval ("layer_shake ()", 50);
	}
}

function layer_shake () {
	objlayer.top = parseInt (objlayer.top) - lay_shake + lay_jedn;
	if (lay_shake < 0) lay_shake += 8;
	lay_shake = lay_shake * -1;
	if (lay_shake == 0) clearInterval (time_shake);
}



function layer_close () {
	if (window.time_shake) clearInterval (time_shake);
	objlayer.visibility = "hidden";
	objlayer.display = "none";
}



if (cookie_newsletter == null) {
	set_cookie("newsletter", "on", 365);
	window.onload = layer_init;
}