using System;
using System.Collections;
using System.Collections.Generic;
using BITKit;
using BITKit.Entities;
using Cysharp.Threading.Tasks;
using Dreamteck.Splines;
using Net.Project.B.Interaction;
using Unity.Mathematics;
using UnityEngine;

namespace Net.Project.B.WorldNode
{
    public class UnitySubwayService:IDisposable
    {
        private readonly IWorldInteractionService _interactionService;
        private readonly IEntitiesService _entitiesService;
        private readonly IFixedTicker _ticker;

        private readonly Dictionary<int, int> _prevPlatform = new();
        private readonly Dictionary<int, SplineComputer> _splineComputers = new();
        private readonly Dictionary<int, float> _distances = new();
        private readonly Dictionary<int, float> _lengths = new();
        private readonly Dictionary<int, float> _vehicleLength=new();
        private readonly HashSet<int> _isBusy = new();

        public UnitySubwayService(IEntitiesService entitiesService, IFixedTicker ticker, IWorldInteractionService interactionService)
        {
            _entitiesService = entitiesService;
            _ticker = ticker;
            _interactionService = interactionService;

            _ticker.Add(OnTick);
            _entitiesService.OnAdd += OnAdd;
        }

        private void OnAdd(IEntity obj)
        {
            if (obj.ServiceProvider.QueryComponents(out UnitySubwayNode subwayNode, out Transform transform))
            {
                var colliders = transform.GetComponentsInChildren<Collider>();
                foreach (var x in colliders)
                {
                    foreach (var y in colliders)
                    {
                        Physics.IgnoreCollision(x, y, true);
                    }
                }
                var spline = _splineComputers[obj.Id] = subwayNode.Spline.GetComponent<SplineComputer>();
                var sample = spline.Project(transform.position);
                var distance = Mathf.Lerp(0, _lengths[obj.Id]=spline.CalculateLength(),(float)sample.percent);

                subwayNode.Subway.isKinematic = true;
                subwayNode.Subway.interpolation = RigidbodyInterpolation.Interpolate;
                
                _distances[obj.Id] = distance;
                
                if(subwayNode.FrontWheel && subwayNode.BackWheel)
                {
                    var localFrontPosition = subwayNode.FrontWheel.localPosition;
                    var localBackPosition = subwayNode.BackWheel.localPosition;
               
                    _vehicleLength[obj.Id] = Vector3.Distance(localFrontPosition, localBackPosition);
                }
            }
        }

        private void OnTick(float obj)
        {
            var gc = GC.GetTotalMemory(false);
            
            var stopNodes = _entitiesService.QueryComponents<IEntity,UnitySubwayPlatformNode, Transform>();

            foreach (var (entity, transform, subwayNode) in _entitiesService
                         .QueryComponents<IEntity, Transform, UnitySubwayNode>())
            {
                if (_isBusy.Contains(entity.Id)) continue;
                var spline = _splineComputers[entity.Id];
                foreach (var (platformEntity, platformNode, platformTransform) in stopNodes)
                {
                    var sample = spline.Project(platformTransform.position);
                    var subwayPosition = transform.position;
                    if (Vector3.Distance(sample.position, subwayPosition) < 1)
                    {
                        if (_prevPlatform.TryGetValue(entity.Id, out var prevPlatform) is false ||
                            prevPlatform != platformEntity.Id)
                        {
                            subwayNode.Subway.isKinematic = true;

                            _prevPlatform[entity.Id] = platformEntity.Id;

                            Arrived(entity.Id, platformNode.StopTime);
                            
                            break;
                        }
                    }

                    var distance = _distances[entity.Id];
                    var length = _lengths[entity.Id];
                    distance =  (distance + subwayNode.Speed * obj) % length;
                    _distances[entity.Id] = distance;

                    var percentage = distance<=0 ? 0 :  distance / length;

                   sample=  spline.Evaluate(percentage,SplineComputer.EvaluateMode.Calculate);

                   if (subwayNode.Offset.sqrMagnitude > 0.1f)
                   {
                       sample.position += sample.rotation * subwayNode.Offset;
                   }
                   
       

                    if (_vehicleLength.TryGetValue(entity.Id, out var vehicleLength))
                    {
                        var sampleFront =spline.Evaluate(GetPercent(distance + vehicleLength / 2)) ;
                        var sampleBack =spline.Evaluate(GetPercent(distance - vehicleLength / 2)) ;
                        
                        var up = Vector3.Cross(sample.forward, sample.right);
                        
                        var rotation = quaternion.LookRotation(sampleFront.position - sampleBack.position, up);
                        
                        subwayNode.Subway.MoveRotation(rotation);

                        var newPosition = Vector3.Lerp(sampleBack.position, sampleFront.position, 0.5f);
                        
                        subwayNode.Subway.MovePosition(newPosition);

                        //_distances[entity.Id] = (float)spline.Project(newPosition).percent * length;
                    }
                    else
                    {
                        subwayNode.Subway.MovePosition(sample.position); //sample.position);
                        subwayNode.Subway.MoveRotation(sample.rotation);
                    }

                    continue;
                    float GetPercent(float d)
                    {
                        d %= length;
                        return d<=0 ? 0 :  d / length;
                    }
                }
            }

            var after = GC.GetTotalMemory(false);

            if (gc != after)
            {
               // Debug.Log($"GC消耗:{gc}=>{after}");
            }
        }

        public void Dispose()
        {
            _ticker.Remove(OnTick);
        }

        private async void Arrived(int id, float stopTime)
        {
            if (_entitiesService.TryGetEntity(id, out var entity) is false) return;
            if (entity.ServiceProvider.QueryComponents(out Transform transform,out UnitySubwayNode subwayNode) is false) return;
            
            Door();

            try
            {
                _isBusy.Add(entity.Id);
                
                await UniTask.Delay(TimeSpan.FromSeconds(stopTime),cancellationToken: entity.CancellationToken);
                
                Door();
                
                await UniTask.Delay(TimeSpan.FromSeconds(4),cancellationToken: entity.CancellationToken);
            }
            catch (OperationCanceledException)
            {
                
            }
            _isBusy.Remove(entity.Id);
            return;
            void Door()
            {
                foreach (var x in transform.GetComponentsInChildren<IEntity>())
                {
                    if (x.ServiceProvider.QueryComponents(out UnityDoorNode doorNode,
                            out IWorldInteractable interactable))
                    {
                        _interactionService.Interaction(this, interactable, WorldInteractionProcess.System);
                    }
                }
            }
        }
    }
}