public static function isFrenchHoliday($unixTimeStamp = null) {
        $date = strtotime(date('m/d/Y', $unixTimeStamp == null ? time() : $unixTimeStamp));
        $year = date('Y', $date);
        $holidays = Cache::getHandler('quick')->get('holiday' . $year);
        if ($holidays == null) {
            $easterDate = easter_date($year) + 3 * 3600;
            $easterDay = date('j', $easterDate);
            $easterMonth = date('n', $easterDate);
            $easterYear = date('Y', $easterDate);
            $holidays = array(
                // Dates fixes
                mktime(0, 0, 0, 1, 1, $year), // 1er janvier
                mktime(0, 0, 0, 5, 1, $year), // Fête du travail
                mktime(0, 0, 0, 5, 8, $year), // Victoire des alliés
                mktime(0, 0, 0, 7, 14, $year), // Fête nationale
                mktime(0, 0, 0, 8, 15, $year), // Assomption
                mktime(0, 0, 0, 11, 1, $year), // Toussaint
                mktime(0, 0, 0, 11, 11, $year), // Armistice
                mktime(0, 0, 0, 12, 25, $year), // Noel
                // Dates variables
                //Lundi de paques
                mktime(0, 0, 0, $easterMonth, $easterDay + 1, $easterYear),
                //Jeudi de l'ascension
                mktime(0, 0, 0, $easterMonth, $easterDay + 39, $easterYear),
                //Lundi pentecote
                mktime(0, 0, 0, $easterMonth, $easterDay + 50, $easterYear),
            );
            Cache::getHandler('quick')->set('holiday' . $year, $holidays);
        }
        return in_array($date, $holidays);
    }