AttachmentEditManager::getContent

public function getContent(): string
{
	$event = $this->event;
	return Calendar::createInstance()
		->setMethod(mb_strtoupper(SenderRequestInvitation::METHOD))
		->setTimezones(Timezone::createInstance()
			->setTimezoneId(Helper::getTimezoneObject($event['TZ_FROM']))
			->setObservance(StandardObservances::createInstance()
				->setOffsetFrom(Helper::getTimezoneObject($event['TZ_FROM']))
				->setOffsetTo(Helper::getTimezoneObject($event['TZ_TO']))
				->setDTStart()
			)
		)
		->addEvent(Event::createInstance($this->uid)
			->setName($event['NAME'])
			->setAttendees($event['ICAL_ATTENDEES'])
			->setStartsAt(Util::getDateObject($event['DATE_FROM'], $event['SKIP_TIME'], $event['TZ_FROM']))
			->setEndsAt(Util::getDateObject($event['DATE_TO'], $event['SKIP_TIME'], $event['TZ_TO']))
			->setCreatedAt(Util::getDateObject($event['CREATED'], false, $event['TZ_FROM']))
			->setDtStamp(Util::getDateObject($event['CREATED'], false, $event['TZ_FROM']))
			->setModified(Util::getDateObject($event['MODIFIED'], false, $event['TZ_FROM']))
			->setWithTimezone(!$event['SKIP_TIME'])
			->setWithTime(!$event['SKIP_TIME'])
			->setOrganizer($event['ICAL_ORGANIZER'], $this->getOrganizerMailTo())
			->setDescription($this->prepareDescription($event['DESCRIPTION']))
			->setTransparent(Dictionary::TRANSPARENT[$event['ACCESSIBILITY']] ?? Dictionary::TRANSPARENT['busy'])
			->setRRule($this->prepareRecurrenceRule($event['RRULE'] ?? null))
			->setLocation($event['TEXT_LOCATION'])
			->setSequence((int)$event['VERSION'])
			->setStatus(Dictionary::EVENT_STATUS['confirmed'])
		)
		->get();
}