/**
 *  @author:    Danny Ng (http://www.dannytalk.com/2010/08/19/read-google-an�¢ï¿½�¦-cookie-script/)
 *  @modified:  19/08/10
 *  @notes:     Free to use and distribute without altering this comment. Would appreciate a link back :)
 */
 
// Strip leading and trailing white-space
String.prototype.trim = function() { return this.replace(/^\s*|\s*$/g, ''); }
 
// Check if string is empty
String.prototype.empty = function() {
    if (this.length == 0)
        return true;
    else if (this.length > 0)
        return /^\s*$/.test(this);
}
 
// Breaks cookie into an object of keypair cookie values
function crumbleCookie(c)
{
    var cookie_array = document.cookie.split(';');
    var keyvaluepair = {};
    for (var cookie = 0; cookie < cookie_array.length; cookie++)
    {
        var key = cookie_array[cookie].substring(0, cookie_array[cookie].indexOf('=')).trim();
        var value = cookie_array[cookie].substring(cookie_array[cookie].indexOf('=')+1, cookie_array[cookie].length).trim();
        keyvaluepair[key] = value;
    }
 
    if (c)
        return keyvaluepair[c] ? keyvaluepair[c] : null;
 
    return keyvaluepair;
}
 
/**
 *  For GA cookie explanation, see http://services.google.com/analytics/breeze/en/ga_cookies/index.html.
 *
 *  @return             -   <void>
 *
 *  @pre-condition      -   pageTracker initialised properly
 *  @post-condition     -   provides 'get' methods to access specific values in the Google Analytics cookies
 */
function gaCookies()
{
    // Cookie syntax: domain-hash.unique-id.ftime.ltime.stime.session-counter
    var utma = function() {
        var utma_array;
 
        if (crumbleCookie('__utma'))
            utma_array =  crumbleCookie('__utma').split('.');
        else
            return null;
 
        var domainhash = utma_array[0];
        var uniqueid = utma_array[1];
        var ftime = utma_array[2];
        var ltime = utma_array[3];
        var stime = utma_array[4];
        var sessions = utma_array[5];
 
        return {
            'cookie': utma_array,
            'domainhash': domainhash,
            'uniqueid': uniqueid,
            'ftime': ftime,
            'ltime': ltime,
            'stime': stime,
            'sessions': sessions
        };
    };
 
    // Cookie syntax: domain-hash.gif-requests.10.stime
    var utmb = function() {
        var utmb_array;
 
        if (crumbleCookie('__utmb'))
            utmb_array = crumbleCookie('__utmb').split('.');
        else
            return null;
        var gifrequest = utmb_array[1];
 
        return {
            'cookie': utmb_array,
            'gifrequest': gifrequest
        };
    };
 
    // Cookie syntax: domain-hash.value
    var utmv = function() {
        var utmv_array;
 
        if (crumbleCookie('__utmv'))
            utmv_array = crumbleCookie('__utmv').split('.');
        else
            return null;
 
        var value = utmv_array[1];
 
        return {
            'cookie': utmv_array,
            'value': value
        };
    };
 
    // Cookie syntax: domain-hash.ftime.?.?.utmcsr=X|utmccn=X|utmcmd=X|utmctr=X
    var utmz = function() {
        var utmz_array, source, medium, name, term, content, gclid;
 
        if (crumbleCookie('__utmz'))
            utmz_array = crumbleCookie('__utmz').split('.');
        else
            return null;
 
        var utms = utmz_array[4].split('|');
        for (var i = 0; i < utms.length; i++) {
            var key = utms[i].substring(0, utms[i].indexOf('='));
            var val = decodeURIComponent(utms[i].substring(utms[i].indexOf('=')+1, utms[i].length));
            val = val.replace(/^\(|\)$/g, '');  // strip () brackets
            switch(key)
            {
                case 'utmcsr':
                    source = val;
                    break;
                case 'utmcmd':
                    medium = val;
                    break;
                case 'utmccn':
                    name = val;
                    break;
                case 'utmctr':
                    term = val;
                    break;
                case 'utmcct':
                    content = val;
                    break;
                case 'utmgclid':
                    gclid = val;
                    break;
            }
        }
 
        return {
            'cookie': utmz_array,
            'source': source,
            'medium': medium,
            'name': name,
            'term': term,
            'content': content,
            'gclid': gclid
        };
    };
 
    // Establish public methods
 
    // utma cookies
    this.getDomainHash = function() { return (utma() && utma().domainhash) ? utma().domainhash : null };
    this.getUniqueId = function() { return (utma() && utma().uniqueid) ? utma().uniqueid : null };
 
    this.getInitialVisitTime = function() { return (utma() && utma().ftime) ? utma().ftime : null };
    this.getPreviousVisitTime = function() { return (utma() && utma().ltime) ? utma().ltime : null };
    this.getCurrentVisitTime = function() { return (utma() && utma().stime) ? utma().stime : null };
    this.getSessionCounter = function() { return (utma() && utma().sessions) ? utma().sessions : null };
 
    // utmb cookies
    this.getGifRequests = function() { return (utmb() && utmb().gifrequest) ? utmb().gifrequest : null };
 
    // utmv cookies
    this.getUserDefinedValue = function () { return (utmv() && utmv().value) ? decodeURIComponent(utmv().value) : null };
 
    // utmz cookies
    this.getCampaignSource = function () { return (utmz() && utmz().source) ? utmz().source : null };
    this.getCampaignMedium = function () { return (utmz() && utmz().medium) ? utmz().medium : null };
    this.getCampaignName = function () { return (utmz() && utmz().name) ? utmz().name : null };
    this.getCampaignTerm = function () { return (utmz() && utmz().term) ? utmz().term : null};
    this.getCampaignContent = function () { return (utmz() && utmz().content) ? utmz().content : null };
    this.getGclid = function () { return (utmz() && utmz().gclid) ? utmz().gclid : null };
}