namespace Tests
{
    public class State
    {
        public State(int id, string name)
        {
            Id = id;
            Name = name;
        }

        public int Id { get; set; }

        public string Name { get; set; }
    }

    public class Trigger
    {
        public Trigger(string name)
        {
            Name = name;
        }

        public string Name { get; set; }
    }

    public class TriggerParameters
    {
        public TriggerParameters(TriggerType triggerType, bool condition)
        {
            TriggerType = triggerType;
            Condition = condition;
        }

        public TriggerType TriggerType { get; set; }
        public bool Condition { get; }
    }

    public enum TriggerType
    {
        Event,
        Option
    }


    [TestFixture]
    public class TestStateless
    {
        [Test]
        public void CreateSimpleStateMachine()
        {
            var startedState = new State(1, "Started");
            var stoppedState = new State(2, "Stopped");

            var startTrigger = new Trigger("Start");
            var stopTrigger = new Trigger("Stop");

            var sm = new StateMachine<State, Trigger>(stoppedState);

            var startTriggerWithParameters = sm.SetTriggerParameters<TriggerParameters>(startTrigger);
            var stopTriggerWithParameters =sm.SetTriggerParameters<TriggerParameters>(stopTrigger);

            sm.OnTransitioned(PrintTransition);
            sm.OnUnhandledTrigger(PrintProhibitedTransition);

            sm.Configure(stoppedState)
                .OnEntry(() => {Console.WriteLine("Entry stopped state");})
                .OnExit(() => { Console.WriteLine("Exit stopped state"); })
                .PermitIf(startTriggerWithParameters, startedState, parameters => parameters.Condition, "Evaluate condition");

            sm.Configure(startedState)
                .OnEntry(() => { Console.WriteLine("Entry started state"); })
                .OnExit(() => { Console.WriteLine("Exit started state"); })
                .PermitIf(stopTrigger, stoppedState, () => true, "Condition name");

            sm.Fire(stopTriggerWithParameters, new TriggerParameters(TriggerType.Event, true));
            sm.Fire(startTriggerWithParameters, new TriggerParameters(TriggerType.Event, false));
            sm.Fire(startTriggerWithParameters, new TriggerParameters(TriggerType.Event, true));
            sm.Fire(stopTriggerWithParameters, new TriggerParameters(TriggerType.Option, false));
        }

        private void PrintTransition(StateMachine<State, Trigger>.Transition transition)
        {
            Console.WriteLine($"Event {transition.Trigger.Name} triggered transition from {transition.Source.Name} to {transition.Destination.Name}");
        }

        private void PrintProhibitedTransition(State state, Trigger trigger, ICollection<string> unmetConditions)
        {
            Console.WriteLine($"Event {trigger.Name} was ignored in state {state.Name}, the following conditions were not met: {string.Join(", ", unmetConditions ?? new List<string>())}");
        }
    }
}