/// <summary>
/// This method tries to change the state the FSM is in based on
/// the current state and the transition passed. If current state
/// doesn't have a target state for the transition passed,
/// an ERROR message is printed.
/// </summary>
public void PerformTransition(FsmTransitionId trans)
{
// Check for NullTransition before changing the current state
if (trans == FsmTransitionId.NullTransition)
{
throw new Exception("FSM ERROR: NullTransition is not allowed for a real transition");
}
// Check if the currentState has the transition passed as argument
FsmStateId id = currentState.GetOutputState(trans);
if (id == FsmStateId.NullStateID)
{
throw new Exception("FSM ERROR: State " + currentStateID.ToString() + " does not have a target state " +
" for transition " + trans.ToString());
}
// Update the currentStateID and currentState
currentStateID = id;
foreach (FsmState state in states)
{
if (state.ID == currentStateID)
{
// Do the post processing of the state before setting the new one
currentState.DoBeforeLeaving();
currentState = state;
// Reset the state to its desired condition before it can reason or act
currentState.DoBeforeEntering();
break;
}
}
} // PerformTransition()
/// <summary>
/// This method delete a state from the FSM List if it exists,
/// or prints an ERROR message if the state was not on the List.
/// </summary>
public void DeleteState(FsmStateId id)
{
// Check for NullState before deleting
if (id == FsmStateId.NullStateID)
{
throw new Exception("FSM ERROR: NullStateID is not allowed for a real state");
}
// Search the List and delete the state if it's inside it
foreach (FsmState state in states)
{
if (state.ID == id)
{
states.Remove(state);
return;
}
}
throw new Exception("FSM ERROR: Impossible to delete state " + id.ToString() +
". It was not on the list of states");
}
// regular add method
public void AddTransition(FsmTransitionId trans, FsmStateId id)
{
// Check if anyone of the args is invalid
if (trans == FsmTransitionId.NullTransition)
{
throw new Exception("FSMState ERROR: NullTransition is not allowed for a real transition");
}
if (id == FsmStateId.NullStateID)
{
throw new Exception("FSMState ERROR: NullStateID is not allowed for a real ID");
}
// Since this is a Deterministic FSM,
// check if the current transition was already inside the map
if (transitionMap.ContainsKey(trans))
{
throw new Exception("FSMState ERROR: State " + stateID.ToString() + " already has transition " + trans.ToString() +
"Impossible to assign to another state");
}
transitionMap.Add(trans, id);
}
/// <summary>
/// This method delete a state from the FSM List if it exists,
/// or prints an ERROR message if the state was not on the List.
/// </summary>
public void DeleteState(FsmStateId id)
{
// Check for NullState before deleting
if (id == FsmStateId.NullStateID)
{
throw new Exception("FSM ERROR: NullStateID is not allowed for a real state");
}
// Search the List and delete the state if it's inside it
foreach (FsmState state in states)
{
if (state.ID == id)
{
states.Remove(state);
return;
}
}
throw new Exception("FSM ERROR: Impossible to delete state " + id.ToString() +
". It was not on the list of states");
}