/// <summary>
/// Add a new transition to the collection of transitions from this state.
/// </summary>
/// <param name="TransitionToAdd">The transition to add.</param>
/// <exception cref="ArgumentException">Thrown if the event in TransitionToAdd has already been used in a transition from this state.</exception>
public void AddTransition(FiniteStateTransition TransitionToAdd)
{
string key = TransitionToAdd.ViaEvent.Name;
if (Transitions.ContainsKey(key))
{
throw new ArgumentException($"Duplicate event name='{key}' used to create a transition from state name='{Name}'.");
}
Transitions.Add(key, TransitionToAdd);
}
/// <summary>
/// Starts the state machine.
///
/// Every state diagram has a start state with a single transition to some initial state in the diagram via a start event.
/// This method performs the following actions:
/// * creates the start state
/// * creates the start event
/// * adds a transition from the start state, via the start event to InitialState, the finite state passed as a parameter
/// * sets the current state to be the start state
/// * raises the start event
/// The OnEntry event handler for InitialState will be executed.
/// The state machine is now sitting in it's initial state and waiting for an event to occur.
///
/// On a technical note, the underlying Thread, in which the event handlers are run, is also created and started here.
/// </summary>
/// <param name="InitialState">The finite state in which this state machine starts.</param>
/// <exception cref="ArgumentException">Thrown if the parameter InitialState is a finite state that has not been added by <see cref="AddState(FiniteState)"/></exception>
public void Start(FiniteState InitialState)
{
string methodName = System.Reflection.MethodBase.GetCurrentMethod().Name;
if (log.IsDebugEnabled)
{
log.Debug($"{methodName}: enter");
}
//if (OnExceptionAction == null)
//{
// throw new ArgumentException($"The state machine must have an OnExceptionAction before you can start it.");
//}
//
// Perform sanity checks
//
foreach (KeyValuePair <string, FiniteState> kvp in ManagedStates)
{
//
// 1. Make sure each finite state has an OnEnterAction
//
FiniteState finiteState = kvp.Value;
if (finiteState.OnEnterAction == null)
{
throw new Exception($"The finite state, '{finiteState.Name}' does not have an OnEnterAction.");
}
//
// 2. Make sure the target state in every transition has been added to the state machine.
//
foreach (KeyValuePair <string, FiniteStateTransition> transitionKvp in finiteState.Transitions)
{
FiniteStateTransition fst = transitionKvp.Value;
string stateName = fst.ToState.Name;
if (!ManagedStates.ContainsKey(stateName))
{
throw new Exception($"The finite state, '{stateName}' has not been added to the state machine.");
}
}
}
FiniteState startState = new FiniteState(START_STATE_NAME);
FiniteStateEvent startEvent = new FiniteStateEvent(START_EVENT_NAME);
startState.OnEnterAction = () => { }; // needs an empty handler
AddState(startState);
startState.AddTransition(startEvent, InitialState);
SetCurrentState(startState);
RaiseEvent(startEvent);
//Thread runner = new Thread(RunStateMachine)
//{
// Name = Name
//};
//runner.Start();
if (log.IsDebugEnabled)
{
log.Debug($"{methodName}: exit");
}
}