/// <summary>
/// This is the default handler if there was neither a transition handler nor an event handler
/// defined. Overriding this method allows to establish a custom error handler or a default
/// event handler defining a default behavior.
/// </summary>
/// <param name="fsmEvent"></param>
protected internal virtual void OnFsmEventDefault(FsmEvent fsmEvent)
{
// error: There exists neither a transition handler nor an event handler
if ( classInfo.hasStates )
{
Trace.WriteLine("FSM:" + this.GetType().Name + " Event:" + fsmEvent.GetType().Name + " not handled in state:"
+ Enum.GetName( classInfo.stateEnumType, GetCurrentState() ) );
}
else
{
Trace.WriteLine("FSM:" + this.GetType().Name + " Event:" + fsmEvent.GetType().Name + " not handled");
}
}
/// <summary>
/// This is the core event dispatching of the FSM. The FSM looks up the
/// curent state and calls the state and transition handlers if they are
/// defined.
/// Override is possible but not recommended.
/// </summary>
/// <param name="fsmEvent"></param>
protected internal virtual void OnFsmEvent(FsmEvent fsmEvent)
{
Debug.Assert( classInfo != null );
if ( classInfo.hasStates )
{
Int32 currState = GetCurrentState();
// execute transition
StateInfo stateInfo1 = classInfo.stateInfoArray[currState];
Debug.Assert( stateInfo1 != null );
MethodInfo methInfoTransition = (MethodInfo)stateInfo1.transitions[fsmEvent.GetType()];
if ( methInfoTransition != null )
{
// first execute exit method
if ( stateInfo1.exitMethod != null )
{
stateInfo1.exitMethod.Invoke(this, new Object[] {fsmEvent});
// it is not allowed to change state in State Exit Handler!
Debug.Assert( currState == GetCurrentState() );
}
// now execute transition method
methInfoTransition.Invoke(this, new Object[] {fsmEvent} );
// on return, FSM has probably a new state
int newState = GetCurrentState();
if ( newState != currState )
{
// Transition to other state
StateInfo stateInfo2 = classInfo.stateInfoArray[newState];
Debug.Assert( stateInfo2 != null );
// Execute Entry state handler of new state
if ( stateInfo2.entryMethod != null )
{
stateInfo2.entryMethod.Invoke(this, new Object[] {fsmEvent,
Enum.ToObject(classInfo.stateEnumType,currState)});
// it is not allowed to change state in State Entry Handler!
Debug.Assert( newState == GetCurrentState() );
}
}
else
{ // It is the same state --> transition loop
if ( stateInfo1.entryMethod != null )
{
stateInfo1.entryMethod.Invoke(this, new Object[] {fsmEvent,
Enum.ToObject(classInfo.stateEnumType,currState)});
// it is not allowed to change state in State Entry Handler!
Debug.Assert( currState == GetCurrentState() );
}
}
}
else
{
// There is no transition for this event in current state.
if ( stateInfo1.defaultTransitionMethod != null )
{
stateInfo1.defaultTransitionMethod.Invoke(this, new Object[] {fsmEvent} );
}
else
{
// Try to find an event handler
MethodInfo methInfoEvHnd = (MethodInfo)classInfo.eventHandlers[fsmEvent.GetType()];
if ( methInfoEvHnd != null )
{
methInfoEvHnd.Invoke(this, new Object[] {fsmEvent} );
}
else
{
// Call default handler
OnFsmEventDefault(fsmEvent);
}
}
}
}
else
{
// FSM has no states. Therefore event handlers are the only handlers to check.
MethodInfo methodInfo = (MethodInfo)classInfo.eventHandlers[fsmEvent.GetType()];
if ( methodInfo != null )
{
methodInfo.Invoke(this, new Object[] {fsmEvent} );
}
else
{
// error: No matching event handler available
Trace.WriteLine("FSM:" + this.GetType().Name + " Event:" + fsmEvent.GetType().Name + " no event handler found");
}
}
}