browser = navigator.appName;
ie = "Microsoft Internet Explorer";
netscape = "Netscape";

var navActive  
var timerID    

function nav(name, menuExist) {
    this.name = name;
    this.menuExist = menuExist;
}

navItem = new Array()
navItem[0] = new nav('link0', 'yes');
navItem[1] = new nav('link1', 'yes');
navItem[2] = new nav('link2', 'yes');
navItem[3] = new nav('link3', 'yes');

function showMenu(navInput) {
    if (browser == netscape) {
        document.layers[navInput].visibility = 'visible';
    }
    else if (browser == ie) {
        document.all[navInput].style.visibility = 'visible';
    }
}

function hideMenu(navInput) {
    if (browser == netscape) {
        document.layers[navInput].visibility = 'hidden';
    }
    else if (browser == ie) {
        document.all[navInput].style.visibility = 'hidden';
    }
}

function showNav(navInput) {
    
}

function hideNav(navInput) {

}

function activateMenu(navInput) {
    stopTimer()
    for (i = 0; i < navItem.length; i++) {
        if (navItem[i].name == navInput) {
            showNav(navItem[i].name);
            if (navItem[i].menuExist == 'yes') {
                showMenu(navItem[i].name);
            }
        }
        else {
            hideNav(navItem[i].name);
            if (navItem[i].menuExist == 'yes') {
                hideMenu(navItem[i].name);
            }
        }
    }
}

function setTimer(navInput) {
    for (i = 0; i < navItem.length; i++) {
        if (navItem[i].name == navInput && navItem[i].menuExist == 'yes') {
            navActive = navItem[i].name;
            timerID = setTimeout('hideNav(navActive),hideMenu(navActive)', 100);
        }
        else if (navItem[i].name == navInput) {
            navActive = navItem[i].name;
            timerID = setTimeout('hideNav(navActive)', 100);
        }
    }
}

function stopTimer() {
    clearTimeout(timerID);
}