/**
* @param string $message
* @param PrivateKeyInterface $privateKey
* @return SignedMessage
*/
public function sign($message, PrivateKeyInterface $privateKey)
{
$hash = $this->calculateMessageHash($message);
return new SignedMessage($message, $this->ecAdapter->signCompact($hash, $privateKey, new Rfc6979($this->ecAdapter, $privateKey, $hash, 'sha256')));
}