Utils::resolveStatus

public function resolveStatus(string $serviceStatus): ?int
{
	$serviceStatus = mb_strtolower($serviceStatus);
	switch ($serviceStatus)
	{
		case 'read':
		case 'sent':
			return MessageStatus::SENT;
		case 'enqueued':
			return MessageStatus::QUEUED;
		case 'delayed':
			return MessageStatus::ACCEPTED;
		case 'delivered':
			return MessageStatus::DELIVERED;
		case 'undelivered':
			return MessageStatus::UNDELIVERED;
		case 'failed':
		case 'cancelled':
			return MessageStatus::FAILED;
		default:
			return
				mb_strpos($serviceStatus, 'error') === 0
					? MessageStatus::ERROR
					: null
				;
	}
}