public uint ProcessFlow()

in src/AmqpLink.cs [585:672]
83 lines of code
18 McCabe index (conditional complexity)

        public uint ProcessFlow(Flow flow)
        {
            uint moreCredit = 0;
            if (flow.Properties != null)
            {
                EventHandler propertyHandler = this.PropertyReceived;
                if (propertyHandler != null)
                {
                    propertyHandler(flow.Properties, EventArgs.Empty);
                    return moreCredit;
                }
            }

            uint flowLinkCredit = flow.LinkCredit();
            bool flowDrain = flow.Drain ?? false;
            lock (this.syncRoot)
            {
                if (this.IsReceiver)
                {
                    this.available = flow.Available ?? uint.MaxValue;
                    this.ApplyTempTotalLinkCredit();
                    if (this.drain && flowLinkCredit == 0)
                    {
                        this.linkCredit = 0;
                        this.deliveryCount = flow.DeliveryCount.Value;
                        this.drain = false;
                    }
                }
                else
                {
                    this.drain = flowDrain;
                    if (flowLinkCredit != uint.MaxValue)
                    {
                        if (this.linkCredit == uint.MaxValue)
                        {
                            this.linkCredit = flowLinkCredit;
                            moreCredit = 0;
                        }
                        else
                        {
                            SequenceNumber otherDeliveryLimit = (flow.DeliveryCount ?? 0u) + flowLinkCredit;
                            SequenceNumber thisDeliveryLimit = this.deliveryCount.Value + this.linkCredit;
                            int delta = otherDeliveryLimit - thisDeliveryLimit;
                            if (delta > 0)
                            {
                                this.linkCredit += (uint)delta;
                                moreCredit = (uint)delta;
                            }
                            else if (delta < 0)
                            {
                                uint reduced = (uint)(-delta);
                                this.linkCredit = reduced > this.linkCredit ? 0 : this.linkCredit - reduced;
                            }
                        }
                    }
                    else
                    {
                        this.linkCredit = uint.MaxValue;
                        moreCredit = uint.MaxValue;
                    }
                }
            }

            bool sendFlow = flow.Echo();
            if (moreCredit > 0 || flowDrain)
            {
                ArraySegment<byte> txnId = this.GetTxnIdFromFlow(flow);
                this.OnCreditAvailable(0, moreCredit, flowDrain, txnId);
                if (this.linkCredit > 0 || flowDrain)
                {
                    this.creditListener?.Invoke(moreCredit, this.drain, txnId);
                }

                if (flowDrain && !this.IsReceiver)
                {
                    this.deliveryCount += (int)this.linkCredit;
                    this.linkCredit = 0;
                    sendFlow = true;
                }
            }

            if (sendFlow)
            {
                this.SendFlow(false, this.drain, properties: null);
            }

            return moreCredit;
        }