public function all()
    {
        $calendars = PublicCalendar::get();
        $events = new ArrayList();
        foreach ($calendars as $cal) {
            $events->merge($cal->Events());
        }


        $eventsArr = $events->toNestedArray();

        //Debug::dump($eventsArr);
        //return false;

        $ics = new ICSExport($eventsArr);
        return $this->output($ics, 'all');
    }