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

namespace BITFALL.Guns
{
    public interface IGunState : IState { }
    
    
    [System.Serializable]
    public abstract class GunState : IGunState
    {
        public BITGun root;
        private IEntityMovement _entityMovement;

        public bool Enabled { get;set; }

        public virtual void Initialize()
        {
            _entityMovement = root.Entity.Get<IEntityMovement>();
            _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>
    {
        //  常数引用
        public const string _Movement = "Movement";
        public const string _Run = "Run";
        public const string _Sprint = "Sprint";
        public const string _Aim = "Aim";
        public const string _Interactive = "Interactive";
        public const string _Equip = "Equip";
        public const string _Fire = "Fire";
        public const string _Reload = "Reload";
        public const string _Melee = "Melee";
        public const string _Climb = "Climb";
        //简单设置
        [Header(Constant.Header.Settings)]
        [SerializeField] private Vector3 bulletInitialOffset;
        [SerializeField] private int initialAimFov = 60;
        [SerializeField] private SpringEulerAngle recoilSpring=new();
        
        //  输入系统
        [Header(Constant.Header.Input)]
        public InputActionReference fireAction;
        public InputActionReference aimAction;
        public InputActionReference reloadAction;
        public InputActionReference meleeAction;
        public InputActionGroup actionGroup = new();
        
        //  依赖注入
        [Header(Constant.Header.Providers)]
        [SerializeReference, SubclassSelector] private IMeleeService meleeService;
        //  引用组件
        [Header(Constant.Header.Components)]
        [SerializeField] private Renderer[] rendererComponents;
        [SerializeField] private VFXPlayer vfxPlayer;
        [SerializeField] private LocationAdditive locationAdditive;
        
        //  引用预制体
        [Header(Constant.Header.Prefabs)]
        [SerializeField] internal AssetableGun assetable;
        [Header(Constant.Header.Reference)]
        
        // 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;
        private IEntityMovement _movement;
        private IPlayerMovement _playerMovement;
        private static readonly int IsGrounded = Animator.StringToHash("IsGrounded");

        #region 接口实现
        public override string AddressablePath => assetable.AddressablePath;
        #endregion
        
        public override void OnAwake()
        {
            base.OnAwake();
            actionGroup.RegisterCallback(fireAction, OnFire);
            actionGroup.RegisterCallback(aimAction, OnAim);
            actionGroup.RegisterCallback(reloadAction, OnReload);
            actionGroup.RegisterCallback(meleeAction, OnMelee);
            _movement = entity.Get<IEntityMovement>();
            _playerMovement = entity.Get<IPlayerMovement>();
            _movement.OnStateChanged += OnMovementStateChanged;
            _movement.OnCommand += OnMovementCommand;
            
        }
        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 void OnStart()
        {
            base.OnStart();
            foreach (var x in rendererComponents)
            {
                x.enabled = false;
            }
        }
        public override void Entry()
        {
            base.Entry();
            var animName = animator.animator.GetCurrentAnimatorStateInfo(0).shortNameHash;
            animator.animator.Play(animName,-1,0);
            animator.animator.enabled = true;
            actionGroup.allowInput.AddElement(this);
            foreach (var x in rendererComponents)
            {
                x.enabled = true;
            }
            expectFiring.Reset();
            Enabled = true;

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

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

            TransitionState(StateDictionary.First().Value);
        }
        public override void Exit()
        {
            actionGroup.allowInput.RemoveElement(this);
            foreach (var x in rendererComponents)
            {
                x.enabled = false;
            }
            expectFiring.Reset();
            animator.animator.enabled = false;
        }
       
        public override void OnUpdate(float deltaTime)
        {
            CurrentState?.OnStateUpdate(deltaTime);
            switch (assetable.FireMode)
            {
                case AutoFireMode:
                    expectFiring.shouldBe = fireAction.action.IsPressed();
                    break;
                case SemiFireMode:
                    expectFiring.shouldBe = fireAction.action.WasPressedThisFrame();
                    break;
                case BurstFireMode when expectFiring.being:
                    expectFiring.shouldBe = fireAction.action.WasPressedThisFrame();
                    if(burstFireInterval.AllowUpdate)
                    {
                        Fire();
                    }
                    break;
            }
            
            animator.animator.SetBool(IsGrounded,_movement.IsGrounded);
            recoilSpring.Update(deltaTime,default);
            
            locationAdditive.AddEuler(recoilSpring.value);
        }

        public override void AnimationEvent(string eventName)
        {
            CurrentState?.AnimationEvent(eventName);
            switch (eventName)
            {
                case "Melee":
                    meleeService.Melee(new MeleeCommand
                    {
                        PlayerId = entity.Id,
                        Position = transform.position,
                        Range = 1
                    });
                    break;
            }
        }
        public void Fire()
        {
            //如果启用了指针则不开火
            if(BITAppForUnity.AllowCursor)
            {
                return;
            }

            //播放射击动画
            animator.Play(BITGun._Fire);

            //调用BulletManager生成子弹
            var _transform = transform;
            var rotation = _transform.rotation;
            BulletService.Spawn(new SpawnBullet
            {
                initiator = entity.Id,
                pos = (_transform.position+rotation * bulletInitialOffset).Fix(),
                rot = rotation,
                forward = _transform.forward.Fix(),
                initialDamage = 32,
            });

            //播放枪口MuzzleFlash
            vfxPlayer.Execute();

            //开火模式逻辑判断
            switch (assetable.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 (assetable.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)
        {
        
        }
        private void OnAim(InputAction.CallbackContext context)
        {
            expectAiming.shouldBe = context.ReadValueAsButton();
        }
    }
    #if UNITY_EDITOR
    [CustomEditor(typeof(BITGun))]
    public class BITGunInspector:BITInspector<BITGun>{}
    #endif
}