/*
|| TASMAI SHRI GURAVE NAMAH ||
(I bow to you, O my teacher)
some (rather most of it) javascript code is borrowed from Jeff Rouyer's
HTMLGURU web site and the tutorial downloaded from it. Whatever is 
coded by me is also inspired and learnt from that site.
Thanks Jeff...

anyone reading this code is encouraged to visit:
HTML Guru Resources: http://www.htmlguru.com
 
*/


function Is() {
    var agent = navigator.userAgent.toLowerCase();
    this.major = parseInt(navigator.appVersion);
    this.minor = parseFloat(navigator.appVersion);
    this.ns  = ((agent.indexOf('mozilla')!=-1) && ((agent.indexOf('spoofer')==-1) && (agent.indexOf('compatible') == -1)));
    this.ns2 = (this.ns && (this.major == 2));
    this.ns3 = (this.ns && (this.major == 3));
    this.ns4b = (this.ns && (this.minor < 4.04));
    this.ns4 = (this.ns && (this.major >= 4));
    this.ie   = (agent.indexOf("msie") != -1);
    this.ie3  = (this.ie && (this.major == 2));
    this.ie4  = (this.ie && (this.major >= 4));
    this.op3 = (agent.indexOf("opera") != -1);
    this.win   = (agent.indexOf("win")!=-1);
    this.mac   = (agent.indexOf("mac")!=-1);
    this.unix  = (agent.indexOf("x11")!=-1);
}

var is = new Is();

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


var curr_selection = "";

function buttonOver(selection) {
    if(curr_selection != selection) {
        buttonImg[selection].src = button_dn.src;
    }
}

function buttonOut(selection) {
    if(curr_selection != selection) {
        buttonImg[selection].src = button_up.src;
    }
}

function imageOver(selection) {
    if(curr_selection != selection) {
        buttonImg[selection].src = eval(selection + "On.src");
    }
}

function imageOut(selection) {
    if(curr_selection != selection) {
        buttonImg[selection].src = eval(selection + "Off.src");
    }
}

function menuToggleBtn(selection) {
    buttonImg[curr_selection].src = button_up.src;
    buttonImg[selection].src = button_dn.src;

    var old_page = eval(menu_selection + "Obj");
    old_page.visibility = "hidden";

    var new_page = eval(selection + "Obj");
    new_page.visibility = "visible";

    curr_selection = selection;
}

function menuToggleImg(selection) {
    buttonImg[curr_selection].src = eval(curr_selection + "Off.src");
    buttonImg[selection].src = eval(selection + "On.src");

    var old_page = eval(menu_selection + "Obj");
    old_page.visibility = "hidden";

    var new_page = eval(selection + "Obj");
    new_page.visibility = "visible";

    curr_selection = selection;
}

function toggleLayerVisibility(selection) {

    var old_page = eval(curr_selection + "Obj");
    old_page.visibility = "hidden";

    var new_page = eval(selection + "Obj");
    new_page.visibility = "visible";

    curr_selection = selection;
}