public void SetCredit()

in src/ReceiverLink.cs [148:207]
53 lines of code
9 McCabe index (conditional complexity)

        public void SetCredit(int credit, CreditMode creditMode, int flowThreshold = -1)
        {
            lock (this.ThisLock)
            {
                if (this.IsDetaching)
                {
                    return;
                }

                if (this.totalCredit < 0)
                {
                    this.totalCredit = 0;
                }

                var sendFlow = false;
                if (creditMode == CreditMode.Drain)
                {
                    if (!this.drain)
                    {
                        // start a drain cycle.
                        this.pending = 0;
                        this.restored = 0;
                        this.drain = true;
                        this.credit = credit;
                        this.flowThreshold = -1;
                        sendFlow = true;
                    }
                }
                else if (creditMode == CreditMode.Manual)
                {
                    this.drain = false;
                    this.pending = 0;
                    this.restored = 0;
                    this.flowThreshold = -1;
                    this.credit += credit;
                    sendFlow = true;
                }
                else
                {
                    this.drain = false;
                    this.flowThreshold = flowThreshold >= 0 ? flowThreshold : credit / 2;
                    // Only change remaining credit if total credit was increased, to allow
                    // accepting incoming messages. If total credit is reduced, only update 
                    // total so credit will be later auto-restored to the new limit.
                    int delta = credit - this.totalCredit + this.restored;
                    if (delta > 0)
                    {
                        this.credit += delta;
                        this.restored = 0;
                        sendFlow = true;
                    }
                }

                this.totalCredit = credit;
                if (sendFlow)
                {
                    this.SendFlow(this.deliveryCount, (uint)this.credit, this.drain);
                }
            }
        }