SmtpServer.Protocol.SmtpCommandFactory.TryMakeAuth C# (CSharp) Method

        public bool TryMakeAuth(TokenEnumerator enumerator, out SmtpCommand command, out SmtpResponse errorResponse)
        {
            Debug.Assert(enumerator.Peek() == new Token(TokenKind.Text, "AUTH"));

            command = null;
            errorResponse = null;

            enumerator.Take();
            enumerator.TakeWhile(TokenKind.Space);

            AuthenticationMethod method;
            if (Enum.TryParse(enumerator.Peek().Text, true, out method) == false)
            {
                _logger.LogVerbose("AUTH command requires a valid method (PLAIN or LOGIN)");

                errorResponse = SmtpResponse.SyntaxError;
                return false;
            }

            enumerator.Take();

            string parameter = null;
            if (enumerator.Count > 0 && _parser.TryMakeBase64(enumerator, out parameter) == false)
            {
                _logger.LogVerbose("AUTH parameter must be a Base64 encoded string");

                errorResponse = SmtpResponse.SyntaxError;
                return false;
            }

            command = new AuthCommand(_options.UserAuthenticator, method, parameter);
            return true;
        }
    }