using Cysharp.Threading.Tasks;
using UnityEngine;

namespace DanieleMarotta.RiversongCodeShowcase
{
    [Service(typeof(IIntentLogicExecutor))]
    [GameSystemGroup(typeof(DefaultAgentsSystemGroup))]
    [UpdateAfter(typeof(AgentManagerSystem))]
    public class IntentExecutionSystem : GameSystem, IInitializable, IUpdatable, IIntentLogicExecutor
    {
        [InjectService]
        private IEntityCollection _entityCollection;

        private readonly IntentExecutionLogic[] _executionLogic = new IntentExecutionLogic[(int)AgentIntentType.Count];

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

        public async UniTask InitializeAsync()
        {
            var pathfindingLogic = new PathfindingIntentExecutionLogic();
            var wanderingLogic = new WanderingExecutionLogic();

            _executionLogic[(int)AgentIntentType.MakeLive] = new MakeLiveIntentExecutionLogic();
            _executionLogic[(int)AgentIntentType.WaitSeconds] = new WaitSecondsIntentExecutionLogic();
            _executionLogic[(int)AgentIntentType.WaitForever] = new WaitForeverIntentExecutionLogic();
            _executionLogic[(int)AgentIntentType.FindPath] = pathfindingLogic;
            _executionLogic[(int)AgentIntentType.SearchResourceNode] = pathfindingLogic;
            _executionLogic[(int)AgentIntentType.SearchFertileTile] = pathfindingLogic;
            _executionLogic[(int)AgentIntentType.SearchCritter] = pathfindingLogic;
            _executionLogic[(int)AgentIntentType.FollowPath] = new FollowPathIntentExecutionLogic();
            _executionLogic[(int)AgentIntentType.MoveToHarvestPosition] = new MoveToHarvestPositionIntentExecutionLogic();
            _executionLogic[(int)AgentIntentType.HarvestResource] = new HarvestResourceIntentExecutionLogic();
            _executionLogic[(int)AgentIntentType.HarvestFertileTile] = new HarvestFertileTileIntentExecutionLogic();
            _executionLogic[(int)AgentIntentType.SetFertileTileLockState] = new SetFertileTileLockStateIntentExecutionLogic();
            _executionLogic[(int)AgentIntentType.FireProjectile] = new FireProjectileExecutionLogic();
            _executionLogic[(int)AgentIntentType.TakeProduct] = new TakeProductIntentExecutionLogic();
            _executionLogic[(int)AgentIntentType.PutProduct] = new PutProductIntentExecutionLogic();
            _executionLogic[(int)AgentIntentType.Wander] = wanderingLogic;
            _executionLogic[(int)AgentIntentType.LoopWandering] = wanderingLogic;
            _executionLogic[(int)AgentIntentType.LookAt] = new LookAtIntentExecutionLogic();
            _executionLogic[(int)AgentIntentType.PlayAnimation] = new PlayAnimationIntentExecutionLogic();

            foreach (var executionLogic in _executionLogic) await executionLogic.InitializeAsync(ServiceLocator);
        }

        public void Update()
        {
            foreach (Agent agent in _entityCollection.GetInternalEntityList(typeof(Agent))) UpdateAgent(agent);
        }

        private void UpdateAgent(Agent agent)
        {
            if (agent.LifecycleState == AgentLifecycleState.DeSpawning)
            {
                CancelRemainingIntents(agent);
                return;
            }

            ref var intentQueue = ref agent.GetIntentQueueRW();

            if (!intentQueue.TryPeekIntent(out var intent))
            {
                agent.IntentExecutionState = IntentExecutionState.EmptyQueue;
                return;
            }

            var executionLogic = _executionLogic[(int)intent.Type];

            if (agent.IntentExecutionState == IntentExecutionState.WaitingIntent)
            {
                if (executionLogic.OnStartingIntent(agent, intent) == IntentExecutionResult.Failure)
                {
                    intentQueue.TryDequeueIntent(out _);
                    CancelRemainingIntents(agent);
                    return;
                }

                agent.IntentExecutionState = IntentExecutionState.ExecutingIntent;
                agent.IntentExecutionTime = 0;
            }

            var result = executionLogic.Execute(agent, intent);
            if (result == IntentExecutionResult.InProgress)
            {
                agent.IntentExecutionTime += Time.deltaTime;
                return;
            }

            intentQueue.TryDequeueIntent(out _);

            if (result == IntentExecutionResult.Failure) CancelRemainingIntents(agent);

            agent.IntentExecutionState = IntentExecutionState.WaitingIntent;
        }

        public ref IntentQueue CancelRemainingIntents(Agent agent)
        {
            ref var intentQueue = ref agent.GetIntentQueueRW();
            while (intentQueue.TryDequeueIntent(out var intent)) _executionLogic[(int)intent.Type].OnCanceled(agent, intent);

            agent.IntentExecutionState = IntentExecutionState.WaitingIntent;

            return ref intentQueue;
        }
    }
}