{

NodeConnectionInteraction(Node& node,

Connection& connection,

FlowScene& scene);

/// Can connect when following conditions are met:

/// 1) Connection 'requires' a port

/// 2) Connection's vacant end is above the node port

/// 3) Node port is vacant

/// 4) Connection type equals node port type, or there is a registered type conversion that can translate between the two

bool canConnect(PortIndex & portIndex,

TypeConverter & converter) const;

/// 1) Check conditions from 'canConnect'

/// 1.5) If the connection is possible but a type conversion is needed, add a converter node to the scene, and connect it properly

/// 2) Assign node to required port in Connection

/// 3) Assign Connection to empty port in NodeState

/// 4) Adjust Connection geometry

/// 5) Poke model to initiate data transfer

bool tryConnect() const;

/// 1) Node and Connection should be already connected

/// 2) If so, clear Connection entry in the NodeState

/// 3) Propagate invalid data to IN node

/// 4) Set Connection end to 'requiring a port'

bool disconnect(PortType portToDisconnect) const;

PortType connectionRequiredPort() const;

QPointF connectionEndScenePosition(PortType) const;

QPointF nodePortScenePosition(PortType portType,

PortIndex portIndex) const;

PortIndex nodePortIndexUnderScenePoint(PortType portType,

QPointF const &p) const;

bool nodePortIsEmpty(PortType portType, PortIndex portIndex) const;

Node* _node;

Connection* _connection;

FlowScene* _scene;