void OnReceiveSessionFrame()

in src/AmqpConnection.cs [553:608]
49 lines of code
9 McCabe index (conditional complexity)

        void OnReceiveSessionFrame(Frame frame)
        {
            AmqpSession session = null;
            Performative command = frame.Command;
            ushort channel = frame.Channel;

            if (command.DescriptorCode == Begin.Code)
            {
                Begin begin = (Begin)command;
                if (begin.RemoteChannel.HasValue)
                {
                    // reply to begin
                    lock (this.ThisLock)
                    {
                        if (!this.sessionsByLocalHandle.TryGetObject(begin.RemoteChannel.Value, out session))
                        {
                            throw new AmqpException(AmqpErrorCode.NotFound, AmqpResources.GetString(AmqpResources.AmqpChannelNotFound, begin.RemoteChannel.Value, this));
                        }

                        session.RemoteChannel = channel;
                        this.sessionsByRemoteHandle.Add(channel, session);
                    }
                }
                else
                {
                    // new begin request
                    AmqpSessionSettings settings = AmqpSessionSettings.Create(begin);
                    settings.RemoteChannel = channel;
                    session = this.SessionFactory.CreateSession(this, settings);
                    this.AddSession(session, channel);
                }
            }
            else
            {
                if (!this.sessionsByRemoteHandle.TryGetObject((uint)channel, out session))
                {
                    if (command.DescriptorCode == End.Code ||
                        command.DescriptorCode == Detach.Code ||
                        this.Settings.IgnoreMissingSessions)
                    {
                        // The session close may timed out already
                        AmqpTrace.Provider.AmqpMissingHandle(this, "session", channel);
                        return;
                    }

                    throw new AmqpException(AmqpErrorCode.NotFound, AmqpResources.GetString(AmqpResources.AmqpChannelNotFound, channel, this));
                }
                else if (command.DescriptorCode == End.Code)
                {
                    this.sessionsByRemoteHandle.Remove((uint)channel);
                    session.RemoteChannel = null;
                }
            }

            session.ProcessFrame(frame);
        }