Globo redirection algorithm

gistfile1.js

    glb.behavior.redirectToMobile = {
        'doc': global.document,
        'loc': global.location,
        'expiresAfter': 1814400,
        'matcherMobile': /android.*mobile|blackberry|docomo|fennec|htc|ip(?:hone|od)|lge|mot|netfront|nokia|opera\sm(?:ini|obi)|samsung-gt-s8500|skyfire|up\.browser|vx10000|wap|windows\s(?:ce|mobile\s7|phone\sos\s7)/i,
        'matcherNotMobile': /android.*(gt-(?:p|n)|shw-|sc-01c|sch-i800|f-01d|ct100)|tablet|xoom/i,
        'matcherMobileReferrer': /m\.globo\.com/,
        'matcherCookieKey': /;?\s*(MOBILEPREF=([01]))/,
        'matcherIndexHtml': /index\.html$/,
        'matcherWWW': /^(https?:\/\/)?www\./,
        'init': function() {
            if (this.isMobile(global.navigator.userAgent)) {
                if (this.cameFromMobile(global.document.referrer)) {
                    this.saveChoice(false);
                } else {
                    if (this.hasCookieKey()) {
                        if (this.wantsMobile()) {
                            this.redirect();
                        }
                    } else {
                        this.saveChoice(true);
                        this.redirect();
                    }
                }
            }
        },
        'isMobile': function(userAgent) {
            var isMobile = this.matcherMobile.exec(userAgent) === null ? false : true;
            if (isMobile) {
                isMobile = this.matcherNotMobile.exec(userAgent) === null ? true : false;
            }
            return isMobile;
        },
        'cameFromMobile': function(referrer) {
            var matcher = this.matcherMobileReferrer;
            return !!matcher.exec(referrer);
        },
        'saveChoice': function(wantMobile) {
            var choice = wantMobile ? 1 : 0,
                expires = new Date();
            expires.setTime(expires.getTime() + this.expiresAfter * 1000);
            this.doc.cookie = 'MOBILEPREF=' + choice + ';expires=' + expires.toUTCString();
        },
        'hasCookieKey': function() {
            var matchCookieKey = this.doc.cookie.match(this.matcherCookieKey);
            if (matchCookieKey) {
                return matchCookieKey[1] === undefined ? false : true;
            } else {
                return false;
            }
        },
        'wantsMobile': function() {
            var matchCookieKey = this.doc.cookie.match(this.matcherCookieKey);
            if (this.hasCookieKey()) {
                return matchCookieKey[2] === '1';
            } else {
                return true;
            }
        },
        'mobileChoosed': function() {
            this.saveChoice(true);
            this.redirect();
        },
        'redirect': function() {
            var url = this.loc.href;
            if (this.matcherIndexHtml.exec(url)) {
                url = url.substring(0, url.length - 10);
            }
            url = url.replace(this.matcherWWW, '$1');
            url = 'http://m.' + url.substring(7);
            this.loc.href = url;
        }
    };
}(this));
(function() {
    var shouldRedirect = 'True' == 'True';
    if (shouldRedirect) {
        glb.behavior.redirectToMobile.init();
    }
}());