using System;
using Cysharp.Threading.Tasks;

namespace DanieleMarotta.RiversongCodeShowcase
{
    public class OnboardingSystem : GameSystem, IInitializable, IDisposable
    {
        [InjectService]
        private ISignalBus _signalBus;

        [InjectService]
        private World _world;

        [InjectService]
        private GameConfig _config;

        public OnboardingSystem(IServiceLocator serviceLocator) : base(serviceLocator)
        {
        }

        public UniTask InitializeAsync()
        {
            _signalBus.Subscribe<BuildingCreatedSignal>(OnBuildingCreated);
            _signalBus.Subscribe<BuildingUpgradedSignal>(OnBuildingUpgraded);
            _signalBus.Subscribe<PathQueryFailedSignal>(OnPathQueryFailed);
            _signalBus.Subscribe<PopulationChangedSignal>(OnPopulationChanged);

            return UniTask.CompletedTask;
        }

        public void Dispose()
        {
            _signalBus.Unsubscribe<BuildingCreatedSignal>(OnBuildingCreated);
            _signalBus.Unsubscribe<BuildingUpgradedSignal>(OnBuildingUpgraded);
            _signalBus.Unsubscribe<PathQueryFailedSignal>(OnPathQueryFailed);
            _signalBus.Unsubscribe<PopulationChangedSignal>(OnPopulationChanged);
        }

        private void OnBuildingCreated(BuildingCreatedSignal signal)
        {
            CompleteEvent(OnboardingEvents.FirstBuildingPlaced);

            if (!signal.Building.Definition.IsHouse) return;

            CompleteEvent(OnboardingEvents.FirstHousePlaced);
        }

        private void OnBuildingUpgraded(BuildingUpgradedSignal signal)
        {
            CompleteEvent(OnboardingEvents.FirstHouseUpgrade);
        }

        private void OnPathQueryFailed(PathQueryFailedSignal signal)
        {
            if ((signal.TraversalRules & PathTraversalRules.RoadsOnly) == 0) return;

            CompleteEvent(OnboardingEvents.FirstRoadFailure);
        }

        private void OnPopulationChanged(PopulationChangedSignal signal)
        {
            if (signal.Population < _config.Onboarding.PopulationMilestone) return;

            CompleteEvent(OnboardingEvents.FirstPopulationMilestone);
        }

        private void CompleteEvent(OnboardingEvents completedEvent)
        {
            var onboardingState = _world.OnboardingState;

            if ((onboardingState.CompletedEvents & completedEvent) != 0) return;

            onboardingState.CompletedEvents |= completedEvent;

            _signalBus.Raise(new OnboardingEventCompleted(completedEvent));
        }
    }
}