DeleteService::getLastViewers

private function getLastViewers(int $userId): array
{
	$this->lastMessageViewers ??= $this->chat->getLastMessageViewsByGroups();

	foreach ($this->lastMessageViewers as $viewers)
	{
		if (isset($viewers['USERS'][$userId]))
		{
			return Common::toJson($viewers['VIEW_INFO'] ?? []);
		}
	}

	return [];
}