ns4 = (document.layers)? true:false
ie4 = (document.all)? true:false

if (!ie4) alert ('Internet Explorer or Netscape Navigator 4.x only')

// Chowanie i odsłanianie warstw
function show(id) {
	if (ns4) document.layers[id].visibility = "show"
	else if (ie4) document.all[id].style.visibility = "visible"
}

function hide(id) {
	if (ns4) document.layers[id].visibility = "hide"
	else if (ie4) document.all[id].style.visibility = "hidden"
}


var loop = true;
var direction = "up";
var speed = 10;
var timer1 = null;
var menu_selection = "wstepDiv";
var wysokosc = 0;

function ustaw(strona) {
	var page = eval(doc + '[strona]' + sty);
	page.top = 90;
	page.left = (szerokosc-120-540)/2;
	menu_selection = strona;
}

function scroll(dir,spd) {
    direction = dir;
    speed = spd;
    var page = eval(doc + '[menu_selection]' + sty);
    var y_pos = parseInt(page.top);
    if(loop == true) {
        if(direction == "dn") {
            page.top = (y_pos-(speed));
            clearTimeout(timer1);
            timer1 = setTimeout("scroll(direction,speed)", 30);
        } else if(direction == "up" && y_pos < 140) {
		if(y_pos<140-speed) {page.top = (y_pos+(speed))}
		else page.top=90;
            clearTimeout(timer1);
            timer1 = setTimeout("scroll(direction,speed)", 30);
        } else if(direction == "top") {
            page.top = 90;
        }
    }
}

if(ns4) {
    doc = "document";
    sty = "";
    htm = ".document"
} else if(ie4) {
    doc = "document.all";
    sty = ".style";
    htm = ""
}

function keyDown(e) {
	var block = eval(doc + '[menu_selection]' + sty);
	if (ns4) {var nKey=e.which; var ieKey=0}
	if (ie4) {var ieKey=event.keyCode; var nKey=0}
	if ((nKey==97 || ieKey==40) && !block.active) { 
		loop=true;
		block.active = true;
		scroll('dn',15)
		block.active = false;
		loop=false;
	}
	if ((nKey==99 || ieKey==38) && !block.active) {
		loop=true;
		block.active = true;
		scroll('up',15)
		block.active = false;
		loop=false;
	}
	if ((nKey==97 || ieKey==34) && !block.active) { 
		loop=true;
		block.active = true;
		scroll('dn',wysokosc-133)
		block.active = false;
		loop=false;
	}
	if ((nKey==99 || ieKey==33) && !block.active) {
		loop=true;
		block.active = true;
		scroll('up',wysokosc-133)
		block.active = false;
		loop=false;
	}

}
function keyUp(e) {
	var block = eval(doc + '[menu_selection]' + sty);
	if (ns4) {var nKey=e.which; var ieKey=0}
	if (ie4) {var ieKey=event.keyCode; var nKey=0}
	if (nKey==97 || ieKey==40) {
		block.active = false;
		loop=false;
	}
	if (nKey==99 || ieKey==38) {
		block.active = false;
		loop=false;
	}
	if (nKey==97 || ieKey==34) { 
		block.active = false;
		loop=false;
	}
	if (nKey==99 || ieKey==33) {
		block.active = false;
		loop=false;
	}

}


function klawisze(){
	if (ns4) block = eval(doc + '[menu_selection]' + sty);
	if (ie4) block = eval(doc + '[menu_selection]' + sty);
	block.xpos = parseInt(block.left)
	block.active = false

	document.onkeydown = keyDown
	document.onkeyup = keyUp
	if (ns4) document.captureEvents(Event.KEYDOWN | Event.KEYUP)
}

function init() {
    if(ns4) {
        szerokosc=innerWidth;
        wysokosc=innerHeight;
    } else if(ie4) {
        szerokosc=document.body.clientWidth;
        wysokosc=document.body.clientHeight;
    }
	
	var gora = 70;
	var lewa = szerokosc-120;

        hide("kontaktyDiv");
        hide("wstepDiv");
        ustaw("produktyDiv");
	show("produktyDiv");
	var warstwa = eval(doc + '["menuDiv"]' + sty);
        warstwa.left = szerokosc - 120;
        warstwa.top = gora;
	var warstwa = eval(doc + '["napisDiv"]' + sty);
        warstwa.left = (szerokosc/2)-(350/2);
	show("napisDiv");
	show("menuDiv");
 	klawisze();
}