void OnReceiveAttach()

in src/AmqpLink.cs [1111:1191]
70 lines of code
18 McCabe index (conditional complexity)

        void OnReceiveAttach(Attach attach)
        {
            StateTransition stateTransition = this.TransitState("R:ATTACH", StateTransition.ReceiveOpen);

            Error error = this.Negotiate(attach);
            if (error != null)
            {
                this.OnLinkOpenFailed(new AmqpException(error));
                return;
            }

            if (stateTransition.From == AmqpObjectState.OpenSent)
            {
                if (this.IsReceiver)
                {
                    Source source = this.settings.Source as Source;
                    if (source != null && source.Dynamic())
                    {
                        source.Address = ((Source)attach.Source).Address;
                    }
                }
                else
                {
                    Target target = this.settings.Target as Target;
                    if (target != null && target.Dynamic())
                    {
                        target.Address = ((Target)attach.Target).Address;
                    }
                }

                if (attach.Properties != null)
                {
                    if (this.Settings.Properties == null)
                    {
                        this.settings.Properties = attach.Properties;
                    }
                    else
                    {
                        this.settings.Properties.Merge(attach.Properties);
                    }
                }
            }
            
            if (stateTransition.To == AmqpObjectState.Opened)
            {
                if ((this.IsReceiver && attach.Source == null) ||
                    (!this.IsReceiver && attach.Target == null))
                {
                    // not linkendpoint was created on the remote side
                    // a detach should be sent immediately by peer with error
                    return;
                }

                if (this.IsReceiver)
                {
                    this.deliveryCount = attach.InitialDeliveryCount.Value;
                    this.settings.Source = attach.Source;
                }
                else
                {
                    this.settings.Target = attach.Target;
                }

                // in some scenario (e.g. EventHub) the service
                // side can override the settle type based on
                // entity settings.
                this.settings.SettleType = attach.SettleType();
                this.CompleteOpen(false, null);
            }
            else if (stateTransition.To == AmqpObjectState.OpenReceived)
            {
                try
                {
                    this.Session.LinkFactory.BeginOpenLink(this, this.OperationTimeout, onProviderLinkOpened, this);
                }
                catch (Exception exception) when (!Fx.IsFatal(exception))
                {
                    this.OnLinkOpenFailed(exception);
                }
            }
        }