public function verify(Message $message)
{
$serviceResponse = $this->service->verifyIpnMessage($message);
$serviceResponseBody = $serviceResponse->getBody();
$pattern = sprintf('/(%s|%s)/', self::STATUS_KEYWORD_VERIFIED, self::STATUS_KEYWORD_INVALID);
if (!preg_match($pattern, $serviceResponseBody)) {
throw new \UnexpectedValueException(sprintf('Unexpected verification status encountered: %s', $serviceResponseBody));
}
return $serviceResponseBody === self::STATUS_KEYWORD_VERIFIED;
}