FCC/Extension/GlobalPumpFdc/WayneLibraries/StateEngineG/StateMachine.cs

#region  --------------- Copyright Dresser Wayne Pignone -------------
/*
 * $Log: /Wrk/WayneLibraries/Wrk/StateEngine/StateMachine.cs $
 * 
 * 22    08-09-19 11:05 roger.månsson
 * 
 * 21    08-03-25 14:15 Mattias.larsson
 * Clean-up.
 * 
 * 20    08-03-25 10:32 Mattias.larsson
 * Ensure debugLogger is not null.
 * 
 * 19    08-03-19 11:44 roger.månsson
 * 
 * 18    08-03-19 11:40 roger.månsson
 * Fixes after code review. Added some lock protections.
 * 
 * 17    08-03-19 11:15 roger.månsson
 * Made timer debug logging Maximized.
 * 
 * 16    08-03-19 9:19 roger.månsson
 * Removed debug code that caused compiler warning.
 * 
 * 15    08-03-18 11:10 roger.månsson
 * Each timer does not have it's own real timer anymore. Instead there are
 * a pool of timers in the StateMachine that can be shared among the
 * timers in the same state machine.
 * 
 * 14    08-03-10 14:59 Mattias.larsson
 * Removed Paused and StepEvent().
 * 
 * 13    08-02-26 14:14 Mattias.larsson
 * Added LogNameKind.
 * Renamed stateName to stateFactoryName.
 * 
 * 12    08-01-23 16:34 Mattias.larsson
 * 
 * 11    07-10-28 14:48 roger.månsson
 * Check if currentState is null before exiting it.
 * 
 * 10    07-09-26 10:51 roger.månsson
 * Throw exception if a state object not can be created by any of the
 * state factories.
 * 
 * 9     07-09-06 7:33 roger.månsson
 * Removed the OnLog event finally, so we can get rid of the warnings.
 * 
 * 8     07-08-17 15:46 roger.månsson
 * Made Initialize() method public, so the state machine can be built up
 * of state objects without starting it.
 * 
 * 7     07-08-15 15:29 roger.månsson
 * Support for new debug log feature. Misc shutdown fixes.
 * 
 * 6     07-08-07 8:26 Mattias.larsson
 * 
 * 5     07-03-12 15:17 roger.månsson
 * Documentation update.
 * 
 * 4     07-03-12 15:00 roger.månsson
 * Implement a Create method that can create both threaded and synchronous
 * state machines.
 */
#endregion
#region Old change history
/*===============================================================================
 * Change history
 * When         Who     Comment
 * ----------   ------  ------------------------------------
 * 2006-08-08   RMa     Added a predicate-based RemovePendingEvents method.
 * 2006-08-08   RMa     Added LogType to the log event args.
 * 2006-07-18   RMa     Major changes, StateMachine is now abstract base class, moved out logic to sub classes CompositeStateMachine,
 *                      RootStateMachine, ThreadedRootStateMachine. Changed transition handling and event handling.
 * 2006-07-03   MLa     Added Transition in StateChangedEventArgs
 * 2006-05-17   RMa     Replaced diagnostic logging with OnLog event. Now it is up to the application
 *                      how the logging should be performed (preferrably using the Wayne.Lib.Log.Logger class)
 * 2006-05-09   RMa     Changed dispose implementation, Obsoleted Stop() method. Use Dispose() instead.
 * 2006-04-26   RMa     Moved out StateChangedEventArgs to its own source file. Implemented IDisposable correctly.
 * 2006-03-02   RMa     FXCop updates: Changed delegate for the OnStateChanged event. Misc updates.
 * 2006-02-23   RMa     Added time to logging.
 * 2006-02-03   RMa     FXCop updates: Implement IDisposable, set internal messages as handled + misc.
 * 2006-02-01   RMa     Check if the state machine is running before stopping it in the destructor.
 * 2006-01-27   RMa     Removed interface Event. Use Event class instead.
 * 2006-01-09   RMa     Create all state objects at startup, otherwise explicit transitions will not work.
 *                      Changed some of the explicit transition handling.
 * 2006-01-06   RMa     Added handling of Explicit transititions.
 *                      Handle transitions asynchronously via the message thread.                  
 * 2005-12-14   RMa     Changed so Internal_Enter is called by the state machine, so we are sure 
 *                      that the internal stuff gets called ,if the user forgets to call base.Enter()....
 * 2005-12-09   RMa     Added IncomingEvent without the highpriority flag that not is used anyway.
 *                      Changed the Init transition so it uses the BasicTransitionType.Init istead of the sting "Init" as type.
 * 2005-12-09   RMa     Fixed some issues with initial state entries.
 * 2005-12-05   RMa     This header added.
 * 
---------------------------------------------------------------------------------*/
#endregion
using System;
using System.Collections.Generic;
using System.Linq;
using Wayne.Lib.Log;
namespace Wayne.Lib.StateEngine
{
    /// <summary>
    /// State machine is the core engine in the Wayne.Lib.StateEngine model. It contains the states, contains the 
    /// information about the state- transition lookup table, and handles the external and internal events.
    /// Normally it should not be neccesary to override this class. 
    /// </summary>
    //[System.Diagnostics.DebuggerNonUserCode()]
    public abstract class StateMachine : IEventConsumer, IDisposable
    {
        #region Fields

        private const bool TimerWrapperCaching = false;

        private InitialState initialState;
        private Dictionary<string, State> createdStates = new Dictionary<string, State>();
        private State currentState;
        private StateTransitionLookup stateLookup;
        internal StateFactories stateFactories = new StateFactories();
        private StateTypeContainer stateTypeContainer;

        internal List<TimerWrapper> timerWrapperList = new List<TimerWrapper>();
        private object timerWrapperListLock = new object();
        private EventHandler timerOnEnableEventHandler;
        private EventHandler timerOnDisableEventHandler;

        private StateMachine parentStateMachine;
        private int depth;
        private bool initialized;
        private object initalizeLock = new object();
        private string name;
        private StateNameKind logNameKind;
        private StateMachine mainStateMachine; // Refers to the main statemachine.

        /// <summary>
        /// Tells whether the object is disposed or not.
        /// </summary>
        protected internal bool disposed;

        /// <summary>
        /// The DebugLogger.
        /// </summary>
        internal protected IDebugLogger debugLogger;

        /// <summary>
        /// The LogCategory.
        /// </summary>
        internal protected object logCategory;

        #endregion

        #region Events

        /// <summary>
        /// Event that signals just before a state change will occur.
        /// </summary>
        public event EventHandler<StateChangedEventArgs> OnStateChange;

        /// <summary>
        /// Event that signals just after a state change has occured.
        /// </summary>
        public event EventHandler<StateChangedEventArgs> OnStateChanged;

        /// <summary>
        /// Even that is fired when the final state of a state machine is reached. 
        /// </summary>
        public event EventHandler OnFinalStateEntered;

        #endregion

        #region Construction

        /// <summary>
        /// Constructor for the StateMachine class.
        /// </summary>
        internal StateMachine(string name, IDebugLogger debugLogger, object logCategory)
        {
            this.name = name;
            this.debugLogger = debugLogger;
            this.logCategory = logCategory;
            this.stateTypeContainer = new StateTypeContainer();
            stateLookup = new StateTransitionLookup(stateTypeContainer);


            timerOnDisableEventHandler = new EventHandler(timer_OnDisable);
            timerOnEnableEventHandler = new EventHandler(timer_OnEnable);
        }

        /// <summary>
        /// Destructor (finalizer). Stops the state machine if it has not already been done.
        /// </summary>
        ~StateMachine()
        {
            Dispose(false);
        }

        #endregion

        #region Public Methods

        /// <summary>
        /// Starts the state machine. This method should be called after the machine has been configured and 
        /// equipped with at least one state factory.
        /// </summary>
        /// <exception cref="StateEngineException">Thrown if the engine is already started.</exception>
        public abstract void Start();

        /// <summary>
        /// Sends an event into the state machine.
        /// </summary>
        /// <param name="stateEngineEvent">Incoming event</param>
        public abstract void IncomingEvent(StateEngineEvent stateEngineEvent);

        /// <summary>
        /// Gets the pending envents from the parentStateMachine.
        /// </summary>
        /// <param name="eventType"></param>
        /// <returns>null or an IEnumberable</returns>
        public virtual IEnumerable<StateEngineEvent> GetPendingEventsOfType(object eventType)
        {
            return parentStateMachine != null ? parentStateMachine.GetPendingEventsOfType(eventType) : null;
        }

        /// <summary>
        /// DO NOT USE for any isfs based event!
        /// Removes all pending events that matches the specified event type. Comparison is made
        /// with the .Equals method.
        /// </summary>
        /// <param name="eventType"></param>
        public virtual void RemovePendingEventsOfType(object eventType)
        {
            if (parentStateMachine != null)
                parentStateMachine.RemovePendingEventsOfType(eventType);
        }

        /// <summary>
        /// Removes all pending event that matches the supplied predicate.
        /// </summary>
        /// <typeparam name="TComparisonObject">Type of the comparison object</typeparam>
        /// <param name="predicate">The predicate that is used to match the event.</param>
        /// <param name="comparisonObject">The comparison object that is used in the StateEngineEventPredicate.</param>
        public virtual void RemovePendingEvents<TComparisonObject>(StateEngineEventPredicate<TComparisonObject> predicate, TComparisonObject comparisonObject)
        {
            if (parentStateMachine != null)
                parentStateMachine.RemovePendingEvents(predicate, comparisonObject);
        }

        /// <summary>
        /// Gets all pending events that matches the supplied predicate
        /// </summary>
        /// <typeparam name="TComparisonObject">Type of the comparison object</typeparam>
        /// <param name="predicate">The predicate that is used to match the event.</param>
        /// <param name="comparisonObject">The comparison object that is used in the StateEngineEventPredicate.</param>
        /// <returns>enumberable of StateEngineEvents</returns>
        public virtual IEnumerable<StateEngineEvent> GetPendingEvents<TComparisonObject>(
            StateEngineEventPredicate<TComparisonObject> predicate, TComparisonObject comparisonObject)
        {
            return parentStateMachine != null ? parentStateMachine.GetPendingEvents(predicate, comparisonObject) : null;
        }

        /// <summary>
        /// Presents the class as a string.
        /// </summary>
        /// <returns></returns>
        public override string ToString()
        {
            return name;
        }

        #endregion

        #region State factory methods

        /// <summary>
        /// Clears the list of state factories.
        /// </summary>
        public void ClearStateFactories()
        {
            stateFactories.Clear();
        }

        /// <summary>
        /// Adds a custom state factory to the factory collection, so it can be used
        /// to create State objects.
        /// </summary>
        /// <param name="factory">The factory to add</param>
        public void AddStateFactory(IStateFactory factory)
        {
            stateFactories.AddFactory(factory);
        }

        #endregion

        #region Private Methods

        /// <summary>
        /// Performs the actual state transition. 
        /// </summary>
        /// <param name="newState">
        /// The state that the machine shall enter.
        /// </param>
        /// <param name="entry">
        ///	Parameters that defines the entry, like HistoryType and the source transition.
        /// </param>
        /// <param name="transition">Perform a transaction by assigning a transition object to this ref parameter.</param>
        private void PerformStateChange(State newState, Wayne.Lib.StateEngine.StateEntry entry, ref Transition transition)
        {
            // First, save the current state
            State oldState = currentState;

            CheckAndRemoveTimersForCurrentState();

            // Set which is the current state.
            currentState = newState;

            // Exit the old state
            if ((oldState != null) && oldState.Active)
                oldState.PerformExit();

            StateChangedEventArgs stateChangeEventArgs = new StateChangedEventArgs(oldState, newState, entry.SourceTransition);

            // Notify descendant classes and others intrested.
            if (OnStateChange != null)
                OnStateChange.Invoke(this, stateChangeEventArgs);

            // Enter the new state.
            currentState.PerformEnter(entry, ref transition);

            // Notify descendant classes and others intrested.
            if (OnStateChanged != null)
                OnStateChanged.Invoke(this, stateChangeEventArgs);
        }


        /// <summary>
        /// Returns a state object that corresponds to the string passed in.
        /// It first checks if the state object already is created and if it
        /// not finds the state, it asks the connected state factories to 
        /// create it.
        /// </summary>
        /// <param name="stateFactoryName">
        /// Name of the state. This should correspond to a state that can 
        /// be created by any of the state factories connected to the 
        /// state machine.
        /// </param>
        /// <returns>
        /// A state object that corresponds to the state name.
        /// If the state can not be found, it will return null.
        /// </returns>
        private State GetState(string stateFactoryName)
        {
            State result;
            if (!createdStates.TryGetValue(stateFactoryName, out result))
            {
                createdStates.Add(stateFactoryName, result = CreateState(stateFactoryName));
            }
            return result;
        }

        /// <summary>
        /// Creates a state from the supplied state name.
        /// </summary>
        /// <param name="stateFactoryName"></param>
        /// <returns></returns>
        internal protected virtual State CreateState(string stateFactoryName)
        {
            State newState = stateFactories.CreateState(stateFactoryName, stateTypeContainer);
            if (newState == null && ParentStateMachine != null)
                newState = ParentStateMachine.stateFactories.CreateState(stateFactoryName, stateTypeContainer);

            if (newState == null && MainStateMachine != null)
                MainStateMachine.stateFactories.CreateState(stateFactoryName, stateTypeContainer);

            if (newState != null)
            {
                newState.WritableFactoryName = stateFactoryName;
                newState.SetParentStateMachine(this);
                newState.SetDebugLogger(debugLogger, logCategory);
            }
            return newState;
        }


        /// <summary>
        /// Forces the state machine to create all its states. It
        /// uses the state transition table to determine which objects are included in
        /// the machine.
        /// </summary>
        private void CreateStateObjects()
        {
            string[] stateFactoryNames = stateLookup.GetStateNameList(false);
            foreach (string stateFactoryName in stateFactoryNames)
            {
                State state = this.GetState(stateFactoryName);
                if (state != null)
                {
                    InitialState tempInitState = state as InitialState;
                    if (tempInitState != null)
                    {
                        initialState = tempInitState;
                    }
                    else
                    {
                        CompositeState compositeState = state as CompositeState;
                        if (compositeState != null)
                        {
                            compositeState.Initialize();
                        }
                    }
                }
                else
                {
                    throw new InvalidOperationException("Can not create state " + stateFactoryName);
                }
            }
        }

        #endregion

        #region Public Properties

        /// <summary>
        /// The state transition lookup object. Use to set up the state machine in code.
        /// </summary>
        public StateTransitionLookup StateTransitionLookup
        {
            get { return stateLookup; }
        }

        /// <summary>
        /// Indicates how many levels the state machine is from the bottom state machine. The first state machine has
        /// depth 0. States in a composite state to that machine has depth 1 and so on.
        /// </summary>
        public int Depth
        {
            get { return depth; }
            set { depth = value; }
        }

        /// <summary>
        /// Current state object.
        /// </summary>
        public State CurrentState
        {
            get { return currentState; }
        }

        /// <summary>
        /// Gets the current state by recursively entering composite states and returning the innermost state.
        /// </summary>
        public State CurrentStateRecursive
        {
            get
            {
                return GetStateRecursively(currentState);
            }
        }

        private State GetStateRecursively(State state)
        {
            if (state is CompositeState)
            {
                var compositeState = ((CompositeState)state);
                if (compositeState.StateMachine.CurrentState == null)
                    return compositeState;
                else
                    return GetStateRecursively(compositeState.StateMachine.CurrentState);
            }
            else
            {
                return state;
            }
        }

        /// <summary>
        /// List of the created states in the machine.
        /// </summary>
        public System.Collections.ObjectModel.ReadOnlyCollection<State> CreatedStates
        {
            get { return createdStates.Values.ToList().AsReadOnly(); }
        }

        /// <summary>
        /// Name of the state machine given when the state machine was created.
        /// </summary>
        public string Name
        {
            get { return name; }
        }

        /// <summary>
        /// Indicates that the state machine has been started.
        /// </summary>
        public abstract bool Started { get; }

        /// <summary>
        /// Initializes the state machine, creates all state objects.
        /// </summary>
        public void Initialize()
        {
            lock (initalizeLock)
            {
                if (!initialized)
                {
                    //Force a creation of all states in the state machine. 
                    CreateStateObjects();

                    if (initialState == null)
                        throw new StateEngineException("Must set an initial state for the state machine! In " + name);
                    initialized = true;
                }
            }
        }

        /// <summary>
        /// The kind of name to use for logging the state name.
        /// </summary>
        public StateNameKind LogNameKind
        {
            get { return MainStateMachine.logNameKind; }
            set { MainStateMachine.logNameKind = value; }
        }

        private StateMachine MainStateMachine
        {
            get
            {
                if (mainStateMachine == null)
                {
                    if (parentStateMachine != null)
                    {
                        mainStateMachine = parentStateMachine;
                        while (mainStateMachine.parentStateMachine != null)
                            mainStateMachine = mainStateMachine.parentStateMachine;
                    }
                    else
                        mainStateMachine = this;
                }
                return mainStateMachine;
            }
        }

        #endregion

        #region Internal Properties

        /// <summary>
        /// If the state machine is contained in a composite state, the state machine
        /// contains a reference to the state machine that owns the composite state.
        /// </summary>
        internal StateMachine ParentStateMachine
        {
            get { return parentStateMachine; }
            set { parentStateMachine = value; }
        }

        /// <summary>
        /// Indicates that all state objects have been created.
        /// </summary>
        internal bool Initialized
        {
            get
            {
                lock (initalizeLock)
                {
                    return initialized;
                }
            }
        }

        /// <summary>
        /// Sets and merges the new state type container with the one that were there to begin with.
        /// </summary>
        /// <param name="newStateTypeContainer"></param>
        public void SetAndMergeTypeContainer(StateTypeContainer newStateTypeContainer)
        {
            newStateTypeContainer.Register(stateTypeContainer); //Copy the registered types from the current type container to the new one.
            stateTypeContainer = newStateTypeContainer;//Overwrite the old one.            
        }

        #endregion

        #region Internal Methods

        /// <summary>
        /// Performs the entry of the initial state of the state machine.
        /// </summary>
        /// <param name="sourceTransition"></param>
        /// <param name="transition">If a transition should be performed, the transition reference is assigned to.</param>
        internal void EnterInitialState(Transition sourceTransition, ref Transition transition)
        {
            StateEntry stateEntry = null;

            if (sourceTransition == null)
            {
                stateEntry = new StateEntry(new Transition(null, BasicTransitionType.Init),
                     this.initialState.FactoryName,
                     HistoryType.None);
            }
            else
            {
                stateEntry = new StateEntry(sourceTransition, this.initialState.FactoryName, HistoryType.None);
            }

            PerformStateChange(this.initialState, stateEntry, ref transition);
            if (transition != null)
                this.HandleTransition(ref transition);
        }

        /// <summary>
        /// When the State machine is contained in a composite state, and the composite state is 
        /// entered, this method is called , so the entry can be done.
        /// </summary>
        /// <param name="stateEntry">The entry containing information about with which history type to enter the state.</param>
        /// <param name="transition">If a transition should be performed, the transition reference is assigned to.</param>
        internal void EnterState(StateEntry stateEntry, ref Transition transition)
        {
            switch (stateEntry.HistoryType)
            {
                /////////////////////////////////
                case HistoryType.None:
                    {
                        EnterInitialState(stateEntry.SourceTransition, ref transition);
                        break;
                    }

                ////////////////////////////////
                case HistoryType.Shallow:
                    {
                        if (currentState != null)
                        {
                            var initEntry = new StateEntry(stateEntry.SourceTransition,
                                initialState.FactoryName,
                                HistoryType.None);

                            PerformStateChange(currentState, initEntry, ref transition);
                        }
                        else
                            EnterInitialState(stateEntry.SourceTransition, ref transition);

                        break;
                    }

                /////////////////////////////////
                case HistoryType.Deep:
                    {
                        if (currentState != null)
                        {
                            var InitEntry = new StateEntry(stateEntry.SourceTransition,
                                initialState.FactoryName,
                                HistoryType.Deep);

                            PerformStateChange(currentState, InitEntry, ref transition);
                        }
                        else
                            EnterInitialState(stateEntry.SourceTransition, ref transition);
                        break;
                    }

                /////////////////////////////////
                case HistoryType.Explicit:
                    {
                        var explicitTransition = stateEntry.SourceTransition;
                        this.HandleTransition(ref explicitTransition);

                        if (explicitTransition != null) //The handleTransition returned a new transition.
                            transition = explicitTransition;
                        break;
                    }
            }
        }

        /// <summary>
        /// When the State machine is contained in a composite state, and the composite state is 
        /// exited, this method is called, so the current state of the machine can be exited.
        /// </summary>
        internal void ExitState()
        {
            lock (this)
            {
                if (currentState != null)//Current state can be null in some rare startup cases.
                    currentState.PerformExit();

                //Clear the timers when exiting.               
                lock (timerWrapperListLock)
                {
                    if ((debugLogger != null) && debugLogger.IsActive(DebugLogLevel.Maximized))
                        debugLogger.Add("Disabling all TimerWrappers", DebugLogLevel.Maximized);
                    var tempTimerWrapperList = new List<TimerWrapper>(timerWrapperList);
                    foreach (var wrapper in tempTimerWrapperList)
                        wrapper.Disable();
                }
            }
        }

        /// <summary>
        /// Handles events
        /// </summary>
        /// <param name="stateEngineEvent"></param>
        /// <param name="transition"></param>
        internal virtual void HandleEvent(StateEngineEvent stateEngineEvent, ref  Transition transition)
        {
            currentState.IncomingEvent(stateEngineEvent, ref transition);

            if (transition != null)
                this.HandleTransition(ref transition);
        }


        /// <summary>
        /// Receives a transition from a state object. Looks up the transition and enters the correct next state.
        /// If this state machine is embedded in a composite state and the transition not resulted in a state change
        /// in this machine, the transition is passed on to the parent machine by changing the reference parameter to a new transition object.
        /// 
        /// It is forbidden to transition from a final state in a state machine, so transitions made while we are 
        /// in a final state is sent right to the state machine that contains the composite state that owns this
        /// machine.
        /// </summary>
        /// <param name="transition"></param>
        internal void HandleTransition(ref Transition transition)
        {
            var explicitTransition = transition as ExplicitTransition;
            bool transitionHandled;

            if (disposed)
                return;

            do
            {
                transitionHandled = false;
                //-------------------------------------
                //If it is NOT an explict transition
                if (explicitTransition == null)
                {
                    //First, Check if this is a transition that has a configured target state
                    //in this state machine.
                    var entry = StateTransitionLookup.GetNextState(currentState.FactoryName, transition);

                    if ((entry != null) && !(currentState is FinalState))
                    {
                        transitionHandled = true;
                        transition = null;

                        var St = this.GetState(entry.TargetStateFactoryName);
                        if (St != null)
                            PerformStateChange(St, entry, ref transition);
                    }
                    //If the current state is a final state, just drop the transition undhandled, and it will be 
                    //passed on to the parent state machine automatically through the ref parameter
                }
                //-------------------------------------
                //Explicit transition
                else
                {
                    State nextState = null;

                    //First search for the state pointed out by the target state, or at least a composite state that 
                    //contains the target state.
                    foreach (var state in createdStates)
                    {
                        if (state.Value.LookupState(explicitTransition.TargetStateFactoryName))
                        {
                            nextState = state.Value;
                            break;
                        }
                    }

                    //If a state was found in this machine, enter the state.
                    if (nextState != null)
                    {
                        var entry = new StateEntry(explicitTransition, nextState.FactoryName, HistoryType.Explicit);
                        transition = null;
                        transitionHandled = true;

                        PerformStateChange(nextState, entry, ref transition);
                    }
                    //If the target state not is found, just drop the transition unhandled and it will be passed 
                    //on to the parent state machine automatically through the ref parameter
                }
            } while (transitionHandled && transition != null && !disposed);

        }

        /// <summary>
        /// Clears all pending events from the state machine.
        /// </summary>
        internal virtual void ClearPendingEvents()
        {
            if (parentStateMachine != null)
                parentStateMachine.ClearPendingEvents();
        }

        /// <summary>
        /// Fires the OnFinalStateEntered event.
        /// </summary>
        internal void FireFinalStateEntered()
        {
            if (OnFinalStateEntered != null)
                OnFinalStateEntered(this, EventArgs.Empty);
        }

        internal void SetDebugLogger(IDebugLogger debugLogger, object logCategory)
        {
            this.debugLogger = debugLogger;
            this.logCategory = logCategory;
        }

        #endregion

        #region IDisposable Members

        /// <summary>
        /// The private dispose method taking into account if it is disposed by the 
        /// finalizer or through a explicit Dispose() call.
        /// </summary>
        /// <param name="disposing"></param>
        protected virtual void Dispose(bool disposing)
        {
            if (!disposed)
            {
                disposed = true;

                if ((debugLogger != null) && debugLogger.IsActive(logCategory))
                    debugLogger.Add("--------- Stopping State machine (Dispose)---------", logCategory);


                if ((currentState != null) && currentState.Active)
                {
                    currentState.PerformExit();
                    currentState = null;
                }

                if (disposing)
                {
                    //Dispose the timer wrappers
                    lock (timerWrapperListLock)
                    {
                        List<TimerWrapper> tempTimerWrapperList = new List<TimerWrapper>(timerWrapperList);
                        foreach (TimerWrapper timerWrapper in tempTimerWrapperList)
                        {
                            timerWrapper.Dispose();
                        }
                        timerWrapperList.Clear();
                    }

                    createdStates.Values.ForEach(x=>x.Dispose());
                    createdStates.Clear();

                    timerOnDisableEventHandler -= timer_OnDisable;
                    timerOnEnableEventHandler -= timer_OnEnable;
                }
            }
        }

        /// <summary>
        /// Disposes resources.
        /// </summary>
        public void Dispose()
        {
            Dispose(true);
            GC.SuppressFinalize(this);
        }
        #endregion

        #region Timer methods

        /// <summary>
        /// Activate the supplied timer. This should be called from state object when they want a timer functionality.
        /// </summary>
        /// <param name="timer">The timer to activate</param>
        /// <see cref="Timer"/>
        public void ActivateTimer(Wayne.Lib.StateEngine.Timer timer)
        {
            timer.OnEnable += timerOnEnableEventHandler;
            timer.OnDisable += timerOnDisableEventHandler;
            timer.Enable();

            if ((debugLogger != null) && debugLogger.IsActive(DebugLogLevel.Maximized))
                debugLogger.Add("Activating timer for " + timer.ToString(), DebugLogLevel.Maximized);
        }

        /// <summary>
        /// A timer should be disabled. Get the timerwrapper for this stateengine timer and 
        /// disable it if it exists.
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        void timer_OnDisable(object sender, EventArgs e)
        {
            Timer stateEngineTimer = (Timer)sender;

            if ((debugLogger != null) && debugLogger.IsActive(DebugLogLevel.Maximized))
                debugLogger.Add("Disabling StateEngineTimer  " + stateEngineTimer.ToString(), DebugLogLevel.Maximized);

            lock (timerWrapperListLock)
            {
                // try to find a timer that  is mapped to this state engine timer.
                TimerWrapper foundTimerWrapper = null;
                foreach (TimerWrapper wrapper in timerWrapperList)
                {
                    if (wrapper.StateEngineTimer == stateEngineTimer)
                    {
                        foundTimerWrapper = wrapper;
                        break;
                    }
                }

                if (foundTimerWrapper != null)
                {
                    foundTimerWrapper.StateEngineTimer = null;

                    if (!TimerWrapperCaching)//Dispose the timer wrapper and remove it from the list. 
                    {
                        foundTimerWrapper.Dispose();
                        timerWrapperList.Remove(foundTimerWrapper);
                    }
                    //else //Old logic, just disable the timer, and cache it. 
                    //{
                    //    foundTimerWrapper.Disable();
                    //}
                }
            }
        }

        /// <summary>
        /// A timer should be enabled, Get a TimerWrapper and attach the state engine timer.
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        void timer_OnEnable(object sender, EventArgs e)
        {
            Timer stateEngineTimer = (Timer)sender;

            if ((debugLogger != null) && (debugLogger.IsActive(DebugLogLevel.Maximized)))
                debugLogger.Add("Enabling StateEngineTimer for  " + stateEngineTimer.ToString(), DebugLogLevel.Maximized);

            lock (timerWrapperListLock) //Lock here just in case. . . 
            {
                TimerWrapper wrapper = GetTimerWrapper(stateEngineTimer);
                wrapper.Enable();
            }
        }



        /// <summary>
        /// Get a TimerWrapper that is 1)Already assigned to this state engine timer, 2) Available to use, 3)If none available, create a new wrapper.
        /// It does also assign the StateEngineTimer to the wrapper, so it is directly marked that it is taken.
        /// </summary>
        /// <param name="stateEngineTimer"></param>
        /// <returns></returns>
        private TimerWrapper GetTimerWrapper(Timer stateEngineTimer)
        {
            TimerWrapper wrapper = null;

            lock (timerWrapperListLock)
            {
                //First try to find a timer that already is mapped to this state engine timer.
                foreach (TimerWrapper tempWrapper in timerWrapperList)
                {
                    if (tempWrapper.StateEngineTimer == stateEngineTimer)
                    {
                        wrapper = tempWrapper;
                        break;
                    }
                }

                //If not found, search for a timerwrapper that is free to use
                if (wrapper == null)
                {
                    foreach (TimerWrapper tempWrapper in timerWrapperList)
                    {
                        if (tempWrapper.StateEngineTimer == null)
                        {
                            wrapper = tempWrapper;
                            wrapper.StateEngineTimer = stateEngineTimer;
                            break;
                        }
                    }
                }

                //Otherwise, create a new wrapper and add it to the list.
                if (wrapper == null)
                {
                    wrapper = new TimerWrapper(TimerFired);
                    wrapper.StateEngineTimer = stateEngineTimer;
                    timerWrapperList.Add(wrapper);
                }
            }

            return wrapper;
        }

        /// <summary>
        /// One of the timers in the timer list has fired. Create a timer event and enqueue it.
        /// </summary>
        /// <param name="state"></param>
        void TimerFired(object state)
        {
            TimerWrapper timerWrapper = (TimerWrapper)state;
            StateEngineEvent stateEngineEvent = null;
            lock (timerWrapperListLock)
            {
                Timer stateEngineTimer = timerWrapper.StateEngineTimer;

                if (stateEngineTimer != null)
                {
                    if ((debugLogger != null) && debugLogger.IsActive(DebugLogLevel.Maximized))
                        debugLogger.Add("StateEngineTimer Fired " + stateEngineTimer.ToString(), DebugLogLevel.Maximized);

                    //If this is a one time timer, it should be removed from the timer list, and be disabled.
                    if (!stateEngineTimer.IsPeriodic)
                    {
                        stateEngineTimer.Disable();
                    }

                    stateEngineEvent = new TimerEvent(stateEngineTimer.UserToken, stateEngineTimer.EventType);
                }
            }

            if (stateEngineEvent != null)
                IncomingEvent(stateEngineEvent); //We want to fire the event outside the lock to see so we don't happen to deadlock with other locks in the state machine.
        }

        /// <summary>
        /// Removes the timers that is owned by the current state, and that is specified to be cleared at exit.
        /// </summary>
        private void CheckAndRemoveTimersForCurrentState()
        {
            //Check if there are any timers that should be removed before leaving the state.
            lock (timerWrapperListLock)
            {
                List<TimerWrapper> tempTimerWrapperList = new List<TimerWrapper>(timerWrapperList); //Create a copy of the timer wrapper list to iterate since it will modify.
                foreach (TimerWrapper timerWrapper in tempTimerWrapperList)
                {
                    if (timerWrapper.StateEngineTimer != null)
                    {
                        if (timerWrapper.StateEngineTimer.OwnerState == currentState)
                        {
                            if (timerWrapper.StateEngineTimer.ClearAtStateExit)
                            {
                                if ((debugLogger != null) && debugLogger.IsActive(DebugLogLevel.Maximized))
                                    debugLogger.Add("!IsPeriodic: Disabling timer because of state change " + timerWrapper.StateEngineTimer.ToString(), DebugLogLevel.Maximized);

                                timerWrapper.StateEngineTimer.Disable();//This will trigger  the wrapper to remove its StateEngineTimer.
                            }
                        }
                    }
                }
            }
        }

        #endregion

        #region Static Methods

        /// <summary>
        /// Creates and returns StateMachine object. This method creates Threaded Statemachine. To create other implementations,
        /// use the <c>Create(StateMachineType stateMachineType, string name)</c> method instead.
        /// </summary>
        /// <param name="name">Name of the state machine.</param>
        /// <param name="debugLogger">The DebugLogger to use.</param>
        /// <param name="logCategory">The log category.</param>
        /// <returns>A statemachine object</returns>
        public static StateMachine Create(string name, IDebugLogger debugLogger, object logCategory)
        {
            return Create(name, StateMachineType.Threaded, debugLogger, logCategory);
        }

        /// <summary>
        /// Creates and returns StateMachine object. The state machine type determines wich implementation should be used.
        /// </summary>
        /// <param name="name">Name of the state machine.</param>
        /// <param name="stateMachineType">Type of state machine implementation that should be created.</param>
        /// <param name="debugLogger">The DebugLogger to use.</param>
        /// <param name="logCategory">The log category.</param>
        /// <returns></returns>
        public static StateMachine Create(string name, StateMachineType stateMachineType, IDebugLogger debugLogger, object logCategory)
        {
            switch (stateMachineType)
            {
                case StateMachineType.Threaded: return new ThreadedRootStateMachine(name, debugLogger, logCategory);
                case StateMachineType.Synchronous: return new SynchronousRootStateMachine(name, debugLogger, logCategory);
                default: throw new NotImplementedException("This statemachine type is not yet implemented.");
            }
        }
        #endregion
    }
}