var isIE = ( (navigator.userAgent.indexOf("Opera") == -1) && (navigator.userAgent.indexOf("MSIE") != -1) );
var classAttr = (isIE) ? "className" : "class";
var tocOn = 0;


// Function to set up main page


function initMain() {
    document.getElementsByTagName("BODY")[0].onclick=rollBanner;
    parseLoc();
    return true;
}



// Functions for managing menus that appear in menu2div


function hideAllSubMenus() {
    var divs = document.getElementsByTagName("DIV");
    var j = divs.length;
    for(var i = 0; i < j; i++) {
        if (divs[i].getAttribute(classAttr) == "menu2div") divs[i].style.display="none";
    }
}


function loadSubMenu(menu) {
    hideAllSubMenus();
    document.getElementById(menu+'Menu').style.display="block";
}



// Functions for parsing parameters given to index.php


function getVars(inpt) {
    var inTokens = inpt.split('&');
    var j = inTokens.length;
    var outTokens = new Array();

    for(var i = 0; i < j; i++) {
        var temp = (inTokens[i].split('='));
        outTokens[temp[0]] = temp[1];
    }
    return outTokens;
}


function parseLoc() {
    var hash = new String(location.search.substring(1)).toLowerCase();
    var tokens = getVars(hash);
    if (tokens) {
        if (tokens['menu']) loadSubMenu(tokens['menu']);
        if (tokens['body']) window.open(tokens['body']+'.html'+(tokens['sub']?'#'+tokens['sub']:''),'contentframe');
    }
}



// Function for changing banner


function rollBanner() {
    if (document.images) {
        var i = Math.floor(banners.length*Math.random());
        var roll = Math.floor(2*Math.random());
        if (roll)  {
            document.getElementById('bannerImg').src = ('images/banner/'+banners[i]);
            return void 0;
        }
    }
}



// Functions for showing & hiding table of contents under yeast button


var tocUp = new Image(31,24); tocUp.src = 'images/toc/up.gif';
var tocDown = new Image(31,24); tocDown.src = 'images/toc/down.gif';


function showToc() {
    document.getElementById('tocDiv').style.visibility = "visible";
    document.getElementById('tocGif').src=tocDown.src;
    document.getElementById('tocBox').onclick=hideToc;
    tocOn = 1;
}


function hideToc() {
    document.getElementById('tocDiv').style.visibility = "hidden";
    document.getElementById('tocGif').src=tocUp.src;
    document.getElementById('tocBox').onclick=showToc;
    tocOn = 0;
}