// S5 slides.js -- released under CC by-sa 2.0 license
//
// Please see http://www.meyerweb.com/eric/tools/s5/credits.html for information 
// about all the wonderful and talented contributors to this code!

var snum = 0;
var smax = 1;
var undef;
var slcss = 1;
var isIE = navigator.appName == 'Microsoft Internet Explorer' ? 1 : 0;
var isOp = navigator.userAgent.indexOf('Opera') > -1 ? 1 : 0;
var isGe = navigator.userAgent.indexOf('Gecko') > -1 && navigator.userAgent.indexOf('Safari') < 1 ? 1 : 0;
var slideCSS = document.getElementById('slideProj').href;

function isClass(object, className) {
    return (object.className.search('(^|\\s)' + className + '(\\s|$)') != -1);
}

function GetElementsWithClassName(elementName,className) {
    var allElements = document.getElementsByTagName(elementName);
    var elemColl = new Array();
    for (i = 0; i< allElements.length; i++) {
        if (isClass(allElements[i], className)) {
            elemColl[elemColl.length] = allElements[i];
        }
    }
    return elemColl;
}

function isParentOrSelf(element, id) {
    if (element == null || element.nodeName=='BODY') return false;
    else if (element.id == id) return true;
    else return isParentOrSelf(element.parentNode, id);
}

function nodeValue(node) {
    var result = "";
    if (node.nodeType == 1) {
        var children = node.childNodes;
        for ( i = 0; i < children.length; ++i ) {
            result += nodeValue(children[i]);
        }       
    }
    else if (node.nodeType == 3) {
        result = node.nodeValue;
    }
    return(result);
}

function slideLabel() {
    var slideColl = GetElementsWithClassName('div','slide');
    var list = document.getElementById('jumplist');
    smax = slideColl.length;
    for (n = 0; n < smax; n++) {
        var obj = slideColl[n];

        var did = 'slide' + n.toString();
        obj.setAttribute('id',did);
        if(isOp) continue;

        var otext = '';
        var menu = obj.firstChild;
        if (!menu) continue; // to cope with empty slides
        while (menu && menu.nodeType == 3) {
            menu = menu.nextSibling;
        }
        if (!menu) continue; // to cope with slides with only text nodes

        var menunodes = menu.childNodes;
        for (o = 0; o < menunodes.length; o++) {
            otext += nodeValue(menunodes[o]);
        }
        list.options[list.length] = new Option(n+' : ' +otext,n);
    }
}

function currentSlide() {
    var cs;
    if (document.getElementById) {
        cs = document.getElementById('currentSlide');
    } else {
        cs = document.currentSlide;
    }
    cs.innerHTML = '<span id="csHere">' + snum + '<\/span> ' + 
        '<span id="csSep">\/<\/span> ' + 
        '<span id="csTotal">' + (smax-1) + '<\/span>';
    if (snum == 0) {
        cs.style.visibility = 'hidden';
    } else {
        cs.style.visibility = 'visible';
    }
}

function go(inc) {
    if (document.getElementById("slideProj").disabled) return;
    var cid = 'slide' + snum;
    if (inc != 'j') {
        snum += inc;
        lmax = smax - 1;
        if (snum > lmax) snum = 0;
        if (snum < 0) snum = lmax;
    } else {
        snum = parseInt(document.getElementById('jumplist').value);
    }
    var nid = 'slide' + snum;
    var ne = document.getElementById(nid);
    if (!ne) {
        ne = document.getElementById('slide0');
        snum = 0;
    }
    document.getElementById(cid).style.visibility = 'hidden';
    ne.style.visibility = 'visible';
    document.getElementById('jumplist').selectedIndex = snum;
    currentSlide();
}

function toggle() {
    var slideColl = GetElementsWithClassName('div','slide');
    var obj = document.getElementById('slideProj');
    if (!obj.disabled) {
        obj.disabled = true;
        for (n = 0; n < smax; n++) {
            var slide = slideColl[n];
            slide.style.visibility = 'visible';
        }
    } else {
        obj.disabled = false;
        for (n = 0; n < smax; n++) {
            var slide = slideColl[n];
            slide.style.visibility = 'hidden';
        }
        slideColl[snum].style.visibility = 'visible';
    }
}

function showHide(action) {
    var obj = document.getElementById('jumplist');
    switch (action) {
    case 's': obj.style.visibility = 'visible'; break;
    case 'h': obj.style.visibility = 'hidden'; break;
    case 'k':
        if (obj.style.visibility != 'visible') {
            obj.style.visibility = 'visible';
        } else {
            obj.style.visibility = 'hidden';
        }
    break;
    }
}

// 'keys' code adapted from MozPoint (http://mozpoint.mozdev.org/)
function keys(key) {
    if (!key) {
        key = event;
        key.which = key.keyCode;
    }
    switch (key.which) {
        case 10: // return
        case 13: // enter
            if (window.event && isParentOrSelf(window.event.srcElement, "controls")) return;
            if (key.target && isParentOrSelf(key.target, "controls")) return;
        case 32: // spacebar
        case 34: // page down
        case 39: // rightkey
        case 40: // downkey
            go(1);
            break;
        case 33: // page up
        case 37: // leftkey
        case 38: // upkey
            go(-1);
            break;
        case 84: // t
            toggle();
            break;
        case 67: // c
            showHide('k');
            break;
    }
}

function clicker(e) {
    var target;
    if (window.event) {
        target = window.event.srcElement;
        e = window.event;
    } else target = e.target;
    if (target.href != null || isParentOrSelf(target, 'controls')) return true;
    if (!e.which || e.which == 1) go(1);
}

function slideJump() {
    if (window.location.hash == null) return;
    var sregex = /^#slide(\d+)$/;
    var matches = sregex.exec(window.location.hash);
    var dest = null;
    if (matches != null) {
        dest = parseInt(matches[1]);
    } else {
        var target = window.location.hash.slice(1);
        var targetElement = null;
        var aelements = document.getElementsByTagName("a");
        for (i = 0; i < aelements.length; i++) {
            var aelement = aelements[i];
            if ( (aelement.name && aelement.name == target)
             || (aelement.id && aelement.id == target) ) {
                targetElement = aelement;
                break;
            }
        }
        while(targetElement != null && targetElement.nodeName != "body") {
            if (targetElement.className == "slide") break;
            targetElement = targetElement.parentNode;
        }
        if (targetElement != null && targetElement.className == "slide") {
            dest = parseInt(targetElement.id.slice(1));
        }
    }
    if (dest != null)
        go(dest - snum);
 }
 
function createControls() {
    controlsDiv = document.getElementById("controls");
    if (!controlsDiv) return;
    controlsDiv.innerHTML = '<form action="#" id="controlForm">' +
    '<div>' +
    '<a accesskey="t" id="toggle" href="javascript:toggle();">&#216;<\/a>' +
    '<a accesskey="z" id="prev" href="javascript:go(-1);">&laquo;<\/a>' +
    '<a accesskey="x" id="next" href="javascript:go(1);">&raquo;<\/a>' +
    '<\/div>' +
    '<div onmouseover="showHide(\'s\');" onmouseout="showHide(\'h\');"><select id="jumplist" onchange="go(\'j\');"><\/select><\/div>' +
    '<\/form>';
}

function notOperaFix() {
    var obj = document.getElementById('slideProj');
    obj.setAttribute('media','screen');
    if (isGe) {
        obj.setAttribute('href','null');   // Gecko fix
        obj.setAttribute('href',slideCSS); // Gecko fix
    }
}

function startup() {
    if (!isOp) createControls();
    slideLabel();
    if (!isOp) {        
        notOperaFix();
        slideJump();
        document.onkeyup = keys;
        document.onclick = clicker;
    }
}

window.onload = startup;