/// <summary>
/// Handles the decryption of the message if needed.
/// We need this handled here because the encrypted messages is sent in a different encoding as opposed to the
/// unencrypted message. The encrypted message is sent in binary and the unencrypted message is sent UTF-8.
/// So an encrypted message should be decrypted first or the conversion might remove some characters or even
/// shorten the actual string.
/// </summary>
/// <param name="bytes">The actual message as a byte array</param>
/// <returns>The unencrypted message as a string without STX/ETX</returns>
public static string DecryptPlainOrEncryptedMessage(byte[] bytes)
{
Logger.LogDebug(HexEncoding.ByteArrayToHexString(bytes));
string message = string.Empty;
bool isInputPlainText = true;
try
{
// Assume that the message is encrypted (this will become the default). It this fails, it's plain.
message = MiniRijndael.DecryptStringFromBytes(bytes);
isInputPlainText = !IsPlainTextQboxMessage(message);
}
catch (ArgumentException)
{
// Ignore, handled below.
}
catch (CryptographicException)
{
// Ignore, handled below.
}
if (isInputPlainText)
{
message = Encoding.UTF8.GetString(bytes);
Logger.LogDebug("Encryption off");
}
else
{
Logger.LogDebug("Encryption on");
}
Logger.LogDebug("Decrypted: {message}", message);
//todo: check refactor this smell. The message is not correctly delimited by the chars.
return(message.WithoutStxEtxEnvelope().Trim());
}