// -- styleSwitcher.js -- //
// -- code by Paul Sowder 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("alternate") == -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;
}

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);
}

document.onblur = function(e) {
    var title = getActiveStyleSheet();
    createCookie("style", title, 365);
}

var cookie = readCookie("style");
var title = cookie ? cookie : getPreferredStyleSheet();
setActiveStyleSheet(title);