using System;
using System.Linq;
using BITFALL.Guns.States;
using BITFALL.Player.Equip;
using BITFALL.Player.Movement;
using UnityEngine;
using BITKit;
using BITKit.Entities;
using BITKit.Entities.Melee;
using UnityEngine.InputSystem;
using BITKit.StateMachine;
using Cysharp.Threading.Tasks;
using Unity.Mathematics;
using UnityEngine.InputSystem.Interactions;
#if UNITY_EDITOR
#endif

namespace BITFALL.Guns
{
    public interface IGunState : IState { }
    
    
    [System.Serializable]
    public abstract class GunState : IGunState
    {
        public BITGun root;
        [Inject]
        protected IEntityMovement _entityMovement;
        public bool Enabled { get;set; }

        public virtual void Initialize()
        {
            root.Entity.Inject(this);
            _entityMovement.OnStateChanged += OnMovementStateChanged;
        }

        public virtual void OnStateEntry(IState old)
        {
        }

        public virtual void OnStateExit(IState old, IState newState)
        {
        }

        public virtual void OnStateUpdate(float deltaTime)
        {
        }
        public virtual void OnMovementStateChanged(IEntityMovementState old, IEntityMovementState newState)
        {
        }
        public virtual void AnimationEvent(string name)
        {
        }
    }
    [System.Serializable]
    public class GunStateMachine : MonoStateMachine<GunState> { }
    public class BITGun : BITEquipBase<GunState>
    {
        //简单设置
        [Header(Constant.Header.Settings)]
        [SerializeField] private Vector3 bulletInitialOffset;
        [SerializeField] private SpringEulerAngle recoilSpring=new();
        [SerializeField] private float recoilPositionWeight=1;

        [Header(Constant.Header.Gameobjects)]
        [SerializeField] private Transform initialSight;
        [SerializeField] private Optional<Transform> newSight;
        
        [Header(nameof(Optional<GameObject>))]
        [SerializeField] private Optional<LocationAdditive> breathingAdditive;
        
        //  输入系统
        [Header(Constant.Header.Input)]
        [SerializeField] internal InputActionReference fireAction;
        [SerializeField] internal InputActionReference aimAction;
        [SerializeField] internal InputActionReference reloadAction;
        [SerializeField] internal InputActionReference meleeAction;
        [SerializeField] internal InputActionReference steadyAimAction;

        [Header(Constant.Header.HotFix)]
        [SerializeField] private Transform cameraView;
        //  引用组件
        [Header(Constant.Header.Components)]
        [SerializeField] private LocationAdditive locationAdditive;
        [SerializeField] private LocationAdditive selfViewAdditive;
        
        //  引用预制体
        [Header(Constant.Header.Prefabs)]
        // 内部变量burst
        [Header(Constant.Header.InternalVariables)]
        public ExpectState<bool> expectFiring;
        public ExpectState<bool> expectAiming;
        internal readonly IntervalUpdate fireInterval = new(0.32f);
        internal readonly IntervalUpdate burstFireInterval = new(0.1f);
        internal int burstFireCount;
        [Inject]
        private IEntityMovement _movement;
        [Inject]
        private IPlayerMovement _playerMovement;
        [Inject]
        private IHealth _health;

        [Inject] private IEquipService _equipService;
        private static readonly int IsGrounded = Animator.StringToHash(BITConstant.Player.IsGrounded);
        private static readonly int IsCrouched = Animator.StringToHash(BITConstant.Player.IsCrouched);
        private AssetableGun _gun=>item as AssetableGun;
        private bool isHolstered;
        private bool isSteadyAim;
        
        public bool RequireBolt { get; set; }
        
        #region 接口实现
        public override string AddressablePath => _gun.AddressablePath;
        #endregion

        public override void OnAwake()
        {
            base.OnAwake();
            inputActionGroup.RegisterCallback(fireAction, OnFire);
            inputActionGroup.RegisterCallback(aimAction, OnAim);
            inputActionGroup.RegisterCallback(reloadAction, OnReload);
            inputActionGroup.RegisterCallback(meleeAction, OnMelee);
            
            if (breathingAdditive.Allow)
                inputActionGroup.RegisterCallback(steadyAimAction, OnSteadyAim);
            _movement.OnStateChanged += OnMovementStateChanged;
            _movement.OnCommand += OnMovementCommand;

            animator[0].onStateExit += (state) => { isHolstered = state is BITConstant.Player.Holster; };
            
            BITAppForUnity.AllowCursor.AddListener(OnAllowCursor);
            destroyCancellationToken.Register(() =>
            {
                BITAppForUnity.AllowCursor.RemoveListener(OnAllowCursor);
            });
        }

        private void OnAllowCursor(bool allow)
        {
            if (!allow) return;
            expectFiring.Reset();
            expectAiming.Reset();
        }

        private void OnSteadyAim(InputAction.CallbackContext obj)
        {
            switch (obj)
            {
                case { interaction: PressInteraction, performed: true } when CurrentState is Aim:
                    isSteadyAim = true;
                    break;
                case { interaction: PressInteraction, canceled: true }:
                    isSteadyAim = false;
                    break;
            }
        }

        private void OnMovementCommand(object obj)
        {
            switch (obj)
            {
                case OnPlayerJumpCommand:
                    animator.Play("Jump");
                    break;
            }
        }

        private void OnMelee(InputAction.CallbackContext obj)
        {
            switch (CurrentState)
            {
                case Equip:
                case Melee:
                    return;
            }
            TransitionState<Melee>();
        }

        private void OnReload(InputAction.CallbackContext obj)
        {
            if (obj.JustPressed() is false) return;
            switch (CurrentState)
            {
                case Equip:
                case Melee:
                    return;
            }
            TransitionState<Reload>();
        }

        private void OnMovementStateChanged(IEntityMovementState arg1, IEntityMovementState arg2)
        {
            foreach (var x in StateDictionary.Values)
            {
                x.OnMovementStateChanged(arg1,arg2);
            }
        }
        public override UniTask EntryAsync()
        {
            base.EntryAsync();
            isHolstered = false;
            
            inputActionGroup.allowInput.AddElement(this);
            expectFiring.Reset();
            Enabled = true;

            fireInterval.Interval = 1f / _gun.FireMode.FireRate;
            fireInterval.Reset();

            if (_gun.FireMode is BurstFireMode burstFireMode)
            {
                burstFireInterval.Interval = burstFireMode.BurstFireInterval;
                burstFireInterval.Reset();
            }

            TransitionState<Equip>();
            
            return UniTask.CompletedTask;
        }

        public override async UniTask ExitAsync()
        {
            TransitionState<Holster>();
            
            _equipService.AllowAttack = false;
            
            inputActionGroup.allowInput.RemoveElement(this);
            expectFiring.Reset();

            cameraView.localPosition = default;

            try
            {
                while (_health.IsAlive && isHolstered is false)
                {
                    destroyCancellationToken.ThrowIfCancellationRequested();
                    _equipService.Zoom.Value = Mathf.MoveTowards(_equipService.Zoom.Value,0,Time.deltaTime);
                    await UniTask.NextFrame();
                }

                _equipService.Zoom.Allow = false;

                destroyCancellationToken.ThrowIfCancellationRequested();

                _equipService.Stable = 1;
              

                await base.ExitAsync();
            }
            catch (OperationCanceledException)
            {
            }
        }
        public override void OnUpdate(float deltaTime)
        {
            UpdateState(deltaTime);
            switch (_gun.FireMode)
            {
                case AutoFireMode:
                    break;
                case SemiFireMode:
                    break;
                case BurstFireMode when expectFiring.being:
                    expectFiring.shouldBe = fireAction.action.WasPressedThisFrame();
                    if(burstFireInterval.AllowUpdate)
                    {
                        switch (AnimationProperties.TryGetValue(BITConstant.Player.AllowFire, out var allowFire))
                        {
                            case false:
                            case true when allowFire >0.9f:
                                Fire();
                                break;
                        }
                    }
                    break;
            }
            
            animator.animator.SetBool(IsGrounded,_movement.IsGrounded);
            animator.animator.SetBool(IsCrouched,_movement.CurrentState is IPlayerCrouchState or IPlayerSlideState);
            animator.animator.SetFloat(BITConstant.Player.SqrMagnitude,_movement.LocomotionBasedVelocity.sqrMagnitude);
            
            recoilSpring.Update(deltaTime,default);
            
            locationAdditive.AddEuler(recoilSpring.value);
            if (selfViewAdditive)
            {
                var positionWeight = recoilPositionWeight;
                if (AnimationProperties.TryGetValue(BITConstant.Player.Aim, out var aim))
                {
                    positionWeight *= Mathf.Lerp(2, 1, aim);
                }
                selfViewAdditive.AddEuler(recoilSpring.value);
                selfViewAdditive.AddPosition(
                    new Vector3(
                        recoilSpring.value.y,
                        -recoilSpring.value.x,
                        recoilSpring.value.z
                    ) *
                    positionWeight
                );
            }

            if(AnimationProperties.TryGetValue(BITConstant.Player.Aim, out var _aim))
            {
                _equipService.Zoom.Allow = CurrentState is Aim;
                _equipService.Zoom.Value =Mathf.Lerp(1,_gun.InitialAimZoom, _aim);
                _equipService.AllowScope = _aim > 0.86f && _gun.IsScopeAim;

                if (breathingAdditive.Allow)
                {
                    var breatheFrequency = 0.5f; // 呼吸的频率，值越大呼吸越快
                    var breatheAmplitude = 0.005f; // 呼吸的幅度，即准星上下移动的最大距离

                    if (_playerMovement.Stamina <= 8)
                    {
                        breatheFrequency = 8;
                        breatheAmplitude = 0.1f;
                    }
                    
                    var breatheOffset = Mathf.Sin(Time.time * breatheFrequency) * breatheAmplitude;

                    if (isSteadyAim)
                    {
                        if (_playerMovement.Stamina > 0)
                        {
                            _playerMovement.Stamina -= 16 * deltaTime;
                            breatheOffset *= 0.16f;
                        }
                        else
                        {
                            isSteadyAim = false;
                        }
                    }
                    else
                    {
                        breatheOffset *= _aim;
                    }
                    
                    _playerMovement.AddViewEuler(new float2(breatheOffset, breatheOffset));
                }

                if (newSight.Allow)
                {
                    transform.localPosition=Vector3.Lerp(default, newSight.Value.position-initialSight.position, _aim);
                }
                else
                {
                    transform.localPosition = default;
                }
            }

            if (AnimationProperties.TryGetValue(BITConstant.Player.Stable, out var stable))
            {
                _equipService.Stable = stable;
            }
            
            if(AnimationProperties.TryGetValue(BITConstant.Player.AllowFire, out var _allowFire))
            {
                _equipService.AllowAttack = _allowFire > 0.9f;
            }
            
            AllowRendering.SetDisableElements(64564,_equipService.AllowScope);

            expectAiming.shouldBe = inputActionGroup.GetAction(aimAction).IsPressed();
        }
        
        public override void AnimationEvent(string eventName)
        {
            if(IsEntered is false) return;
            base.AnimationEvent(eventName);
            CurrentState?.AnimationEvent(eventName);
            // switch (eventName)
            // {
            //     case "Melee":
            //         meleeService.Melee(new MeleeCommand
            //         {
            //             PlayerId = Entity.Id,
            //             Position = Transform.position,
            //             Force = Transform.forward * 128,
            //             Range = 1
            //         });
            //         break;
            // }
        }
        public void Fire()
        {
            if (RequireBolt) return;
        

            //播放射击动画
            UnityEntity.Invoke(Constant.Animation.Play, BITConstant.Player.Fire);

            if (_gun.BuckShot.Allow)
            {
                InternalAddRecoil();
                for (int i = 0; i < _gun.BuckShot.Value; i++)
                {
                    InternalFire();    
                }
            }
            else
            {
                InternalFire();    
                InternalAddRecoil();
            }
           

            //开火模式逻辑判断
            switch (_gun.FireMode)
            {
                case AutoFireMode:
                    break;
                case SemiFireMode:
                    //如果是半自动开火,则取消射击
                    expectFiring.Reset();
                    break;
                case BurstFireMode burstFireMode:
                    burstFireCount++;
                    expectFiring.being = true;
                    if(burstFireCount > burstFireMode.BurstRound)
                    {
                        burstFireCount = 0;
                        expectFiring.Reset();
                    }
                    break;
            }

            if (_gun.FireMode is SemiFireMode {RequireBoltAction:true})
            {
                RequireBolt = true;
            }
        }

        private void InternalFire()
        {
            //调用BulletManager生成子弹
            var _transform = transform;
            var rotation = _transform.rotation;
            var random = UnityEngine.Random.insideUnitCircle;
            if (_gun.TryGetProperty<ISpread>(out var spread))
            {
                random *= spread.Spread;
            }
            if(AnimationProperties.TryGetValue(BITConstant.Player.Aim, out var aim))
            {
                random *= Mathf.Lerp(_gun.InitialHipFireSpread,1,aim);
            }
            random *= recoilSpring.value.GetLength();
            BulletService.Spawn(new SpawnBullet
            {
                Initiator = Entity.Id,
                Position = (_transform.position+rotation * bulletInitialOffset),
                Rotation = rotation,
                Forward = rotation * (Vector3.forward + Vector3.up * random.y + Vector3.right * random.x),
                InitialDamage = _gun.InitialDamage,
                StartSpeed = _gun.InitialBulletSpeed,
                InitialForce = _gun.InitialBulletForce,
            });
        }

        private void InternalAddRecoil()
        {
            if (_gun.TryGetProperty<IRecoil>(out var _recoil))
            {
                var _newRecoil =  new Vector3
                {
                    x = _recoil.Recoil.x,
                    y = _recoil.Recoil.y.Random(),
                    z = _recoil.Recoil.z.Random()
                };
                recoilSpring.value = _newRecoil;
                _playerMovement.AddViewEuler(new float2(_newRecoil.x,_newRecoil.y));
            }
        }
        private void OnFire(InputAction.CallbackContext context)
        {
            //如果启用了指针则不开火
            if(BITAppForUnity.AllowCursor)
            {
                expectFiring.Reset();
                return;
            }
            switch (_gun.FireMode)
            {
                case AutoFireMode :
                    switch (context)
                    {
                        case {interaction:PressInteraction , started:true}:
                            expectFiring.shouldBe = true;
                            break;
                        case {interaction:PressInteraction , canceled:true}:
                            expectFiring.shouldBe = false;
                            break;
                    }
                    break;
                case SemiFireMode:
                    switch (context)
                    {
                        case { interaction: PressInteraction, started: true } when fireInterval.AllowUpdateWithoutReset && RequireBolt is false:
                            expectFiring.shouldBe = true;
                            break;
                    }
                    break;
            }
        }
        private void OnAim(InputAction.CallbackContext context)
        {
            //如果启用了指针则不开火
            if(BITAppForUnity.AllowCursor)
            {
                expectAiming.Reset();
                return;
            }
            //expectAiming.shouldBe = context.ReadValueAsButton();
        }
    }
    // #if UNITY_EDITOR
    // [CustomEditor(typeof(BITGun))]
    // public class BITGunInspector:BITInspector<BITGun>{}
    // #endif
}