use Concrete\Core\Calendar\Calendar;
use Concrete\Core\Calendar\Event\EventRepetition;
use Concrete\Core\Calendar\Event\EditResponse;
use Concrete\Core\Calendar\Event\EventOccurrenceList;
use Concrete\Core\Calendar\Event\EventService;
use Concrete\Core\Entity\Calendar\CalendarEvent;
use Concrete\Core\Entity\Calendar\CalendarEventVersionRepetition;
use Concrete\Core\Entity\Calendar\CalendarEventRepetition;
use Concrete\Core\User\User;
use Concrete\Core\Workflow\Request\ApproveCalendarEventRequest;
 
$app = \Concrete\Core\Support\Facade\Application::getFacadeApplication();
 
$calendar = Calendar::getByName($calendarName);
$eventService = $app->make(EventService::class);
$u = User::getByUserID(1);
$timezone = $calendar->getSite()->getConfigRepository()->get('timezone');
if (!$timezone) {
    $timezone = date_default_timezone_get();
}
$timezone = new \DateTimeZone($timezone);
 
$dateStart = date('Y-m-d H:i:s', strtotime($start));
$dateEnd = date('Y-m-d H:i:s', strtotime($end));
 
$pd = new EventRepetition();
$pd->setTimezone($timezone);
$pd->setStartDateAllDay(0);
$pd->setStartDate($dateStart);
$pd->setEndDate($dateEnd);
$pd->setRepeatPeriod($pd::REPEAT_NONE);
$pdEntity = new CalendarEventRepetition($pd);
 
$event = new CalendarEvent($calendar);
$eventVersion = $eventService->getVersionToModify($event, $u);
$eventVersion->setName($title);
$eventVersion->setDescription(NULL);
 
$repetitions[] = new CalendarEventVersionRepetition($eventVersion, $pdEntity);
$eventService->addEventVersion($event, $calendar, $eventVersion, $repetitions);
$eventService->generateDefaultOccurrences($eventVersion);
 
$pkr = new ApproveCalendarEventRequest();
$pkr->setCalendarEventVersionID($eventVersion->getID());
$pkr->setRequesterUserID($u->getUserID());
$response = $pkr->trigger();