/*****************************************************************************
javascript.js
*****************************************************************************/
function TabPageClick(oBtn) {
    aNameParts = oBtn.id.split('_');
    iBtnClickedIndex = parseInt(aNameParts[2]);         // the index of the clicked button
    if (oBtn.className == "navUnselected") {
        return true; // already selected 
    }

    oBtn.className = "navUnselected";

    for (i = 1; i <= 6; i++) {
        if (i == iBtnClickedIndex) {
            document.getElementById("uiTabPageDiv_" + aNameParts[1] + "_" + iBtnClickedIndex).style.display = "block"; // show the clicked layer
            continue;
        }

        oBtn = document.getElementById("uiTabControl_" + aNameParts[1] + "_" + i);
        if (oBtn) {
            document.getElementById("uiTabPageDiv_" + aNameParts[1] + "_" + i).style.display = "none";
            oBtn.className = "navSelected";
        } else {
            break;
        }
    }
}

function OpenWindow() {
    var url = "/_layouts/FRV/TipAFriend/Default.aspx/?page=" + document.location.href;
    window.open(url, '', 'toolbar=0,directories=0,status=0,scrollbars=0,resizable=0,copyhistory=0,width=400,height=500');
}

function ChangeTextSize(fontSize) {
    var elem = document.getElementsByTagName('body');
    if (elem != null) {
        if (fontSize == "s") {
            elem[0].style.fontSize = "52.5%";
        }
        else if (fontSize == "l") {
            elem[0].style.fontSize = "82.5%";
        }
        else {
            elem[0].style.fontSize = "62.5%";
        }
    }
}





/*****************************************************************************
Stylesheet swapping
Taken from: http://www.alistapart.com/articles/alternate/
*****************************************************************************/
function setActiveStyleSheet(title) {
    var i, a, main;
    for (i = 0; (a = document.getElementsByTagName("link")[i]); i++) {
        if (a.getAttribute("rel").indexOf("style") != -1 && a.getAttribute("title")) {
            a.disabled = true;
            if (a.getAttribute("title") == title) a.disabled = false;
        }
    }
}

function getActiveStyleSheet() {
    var i, a;
    for (i = 0; (a = document.getElementsByTagName("link")[i]); i++) {
        if (a.getAttribute("rel").indexOf("style") != -1 && a.getAttribute("title") && !a.disabled) return a.getAttribute("title");
    }
    return null;
}

function getPreferredStyleSheet() {
    var i, a;
    for (i = 0; (a = document.getElementsByTagName("link")[i]); i++) {
        if (a.getAttribute("rel").indexOf("style") != -1
       && a.getAttribute("rel").indexOf("alt") == -1
       && a.getAttribute("title")
       ) return a.getAttribute("title");
    }
    return null;
}

function createCookie(name, value, days) {
    if (days) {
        var date = new Date();
        date.setTime(date.getTime() + (days * 24 * 60 * 60 * 1000));
        var expires = "; expires=" + date.toGMTString();
    }
    else expires = "";
    document.cookie = name + "=" + value + expires + "; path=/";
}

function readCookie(name) {
    var nameEQ = name + "=";
    var ca = document.cookie.split(';');
    for (var i = 0; i < ca.length; i++) {
        var c = ca[i];
        while (c.charAt(0) == ' ') c = c.substring(1, c.length);
        if (c.indexOf(nameEQ) == 0) return c.substring(nameEQ.length, c.length);
    }
    return null;
}

// ===== OLD IMPLEMENTATION - less code, not very good (and it doesn't work!) =====
/*window.onload = function(e) {
var cookie = readCookie("style");
var title = cookie ? cookie : getPreferredStyleSheet();
setActiveStyleSheet(title);
}
window.onunload = function(e) {
var title = getActiveStyleSheet();
createCookie("style", title, 365);
}
var cookie = readCookie("style");
var title = cookie ? cookie : getPreferredStyleSheet();
setActiveStyleSheet(title);*/

// ===== NEW IMPLEMENTATION - more code, but a lot better (and it works!) =====
// Needs mootools-1.2.2.js
window.addEvent('domready', function() {
    var cookie = readCookie("style");
    var title = cookie ? cookie : getPreferredStyleSheet();
    setActiveStyleSheet(title);
});
window.addEvent('unload', function() {
    var title = getActiveStyleSheet();
    createCookie("style", title, 365);
});