using Entitas;
using System.Collections.Generic;
using UnityEngine;
using Game;

public class SettleSystem : IExecuteSystem, IInitializeSystem
{
    private IGroup<GameEntity> _entities;
    private readonly List<SkillHitInfo> _tempHitInfo = new List<SkillHitInfo>();

    public void Initialize()
    {
        _entities = Util.GetGroup(GameMatcher.Skill);
    }

    public void Execute()
    {
        foreach (var entity in _entities)
        {
            SettleDebugDraw(entity);
            SettleSkill(entity);
        }
    }

    private static void SettleDebugDraw(GameEntity entity)
    {
        if (!entity.hasHp)
            return;

        Util.DrawShape(entity.hp.HitBoxShape, entity.Pos(), Vector3.right, new Color(0, 1, 0, 0.4f));
    }

    private static void SettleSkill(GameEntity entity)
    {
        if (Util.IsPause(entity))
            return;
        while (entity.skill.HitInfo.Count > 0)
            if (SettleHit(entity.skill.HitInfo.Dequeue()))
                break;
    }

    private static bool SettleHit(SkillHitInfo hitInfo)
    {
        var entity = Util.GetEntity(hitInfo.OwnerEntity);
        var target = Util.GetEntity(hitInfo.HitEntity);
        if (entity == null || target == null)
        {
            return false;
        }

        var damageResult = SettleDamage(hitInfo, entity, target); //伤害结算
        var hitLevel = SettleHitLevel(hitInfo, damageResult, entity, target); //命中效果等级
        var flowSpeed = SettleFlowSpeed(hitInfo, hitLevel, entity, target); //强制位移(击退、击飞、击落等)
        var pauseTime = SettlePause(hitInfo, hitLevel, entity, target); //卡帧
        SettleSelfMoveForceScale(hitLevel, entity, target); //攻击者移动速度调整
        SettleBreak(flowSpeed, hitLevel, damageResult, entity, target); //打断技能/动画
        SettleBuff(hitLevel, entity, target); //添加硬直/击晕buff
        SettleTrigger(hitInfo, entity, target); //命中触发器

        //纯表现
        SettleHitText(hitLevel, damageResult, entity, target); //跳字
        SettleHitEffect(flowSpeed, hitLevel, hitInfo.SkillParam.hitType, entity, target); //命中特效
        SettleFlash(hitLevel, entity, target); //闪白
        SettleShake(hitLevel, entity, target); //抖动
        SettleScale(flowSpeed, entity, target); //抖动
        SettleGlobalEffect(target, pauseTime); //全局特效
        
        //投技中断
        if (!(hitInfo.SkillParam.throwTimeline is null))
        {
            entity.skill.ThrowTarget = target.ID();
            TimelineManager.Instance.RunSkillTimeline(entity, hitInfo.SkillParam.throwTimeline.name);
            return true;
        }

        return !hitInfo.Continue;
    }

    public struct SettleDamageResult
    {
        public float Damage; //伤害
        public bool HasShield; //是否结算前有护盾
        public bool IsSkill; //是否技能造成伤害
        public bool IsDead; //当次伤害造成死亡
        public bool IsShieldBreak; //当次伤害破盾
        public bool IsStun; //当次伤害眩晕
        public bool IsFlowing; //是否浮空
    }

    private static SettleDamageResult SettleDamage(SkillHitInfo hitInfo, GameEntity entity, GameEntity target)
    {
        var param = hitInfo.SkillParam;
        var targetHp = target.hp;

        var ret = new SettleDamageResult();
        ret.IsSkill = !string.IsNullOrEmpty(hitInfo.SkillId);
        //伤害计算
        {
            var basicAttack = Util.GetProperty(entity, EProperty.BasicAttack);
            ret.Damage = basicAttack * param.damageRate * hitInfo.AttackRate;
            ret.HasShield = targetHp.Shield.Value > 0;
            if (ret.HasShield)
            {
                ret.Damage = Mathf.Min(ret.Damage, targetHp.Shield.Value);
                targetHp.Shield.Value -= ret.Damage;
                ret.IsShieldBreak = targetHp.Shield.Value == 0;
            }
            else
            {
                ret.Damage = Mathf.Min(ret.Damage, targetHp.Hp.Value);
                targetHp.Hp.Value -= ret.Damage;
            }

            targetHp.IsDamaged.Value = true;
            //刷新护盾恢复cd
            target.hp.ShieldRecoverTime = target.hp.ShieldRecoverTimeMax;
            //刷新眩晕恢复cd
            target.hp.StunRecoverTime = target.hp.StunRecoverTimeMax;
        }

        //异常值积累
        {
            if (targetHp.StunMax.Value > targetHp.Stun.Value)
            {
                //眩晕
                var basicStun = Util.GetProperty(entity, EProperty.BasicStun);
                var damageStun = basicStun * param.stunRate * hitInfo.StunkRate;
                damageStun = Mathf.Min(damageStun, targetHp.StunMax.Value - targetHp.Stun.Value);
                targetHp.Stun.Value += damageStun;
                if (targetHp.Stun.Value >= targetHp.StunMax.Value)
                {
                    ret.IsStun = true;
                    targetHp.Stun.Value = 0;
                    Util.AddStunBuff(target.ID());
                }
            }
        }

        //浮空判定 目标不在地面 或者可以从地面浮空
        if (!target.move.IsGround || param.isFlow)
        {
            ret.IsFlowing = true;
        }

        //实体死亡
        if (targetHp.IsAlive && targetHp.Hp.Value == 0)
        {
            ret.IsDead = true;
            Util.EntityDie(target);
        }

        return ret;
    }

    private static EHitLevel SettleHitLevel(SkillHitInfo hitInfo, SettleDamageResult dmgResult, GameEntity entity,
        GameEntity target)
    {
        if (!dmgResult.IsSkill)
        {
            return EHitLevel.None;
        }

        if (dmgResult.IsDead)
        {
            return EHitLevel.Kill;
        }

        if (dmgResult.IsShieldBreak)
        {
            return EHitLevel.ShieldBreak;
        }

        if (dmgResult.IsStun)
        {
            return EHitLevel.Stun;
        }

        var staggerDef = Util.GetProperty(target, EProperty.StaggerDefLevel);
        if (dmgResult.HasShield)
        {
            staggerDef += Util.GetProperty(target, EProperty.ShieldStaggerDefLevel);
        }

        var sub = hitInfo.SkillParam.staggerLevel - staggerDef;
        sub = Mathf.Clamp(sub, 0, 3);
        var ret = EHitLevel.None;
        switch (sub)
        {
            case 0:
                ret = EHitLevel.Block;
                break;
            case 1:
                ret = EHitLevel.Stagger1;
                break;
            case 2:
                ret = EHitLevel.Stagger2;
                break;
            case 3:
                ret = EHitLevel.Stagger3;
                break;
        }

        if (ret > EHitLevel.Block)
        {
            if (dmgResult.IsFlowing)
            {
                return EHitLevel.Flowing;
            }

            if (target.hp.LastDamageLevel == EHitLevel.Stagger3)
            {
                //后仰升级为浮空
                return EHitLevel.Flowing;
            }
        }

        return ret;
    }

    private static Vector3 SettleFlowSpeed(SkillHitInfo hitInfo, EHitLevel hitLevel, GameEntity entity,
        GameEntity target)
    {
        var param = hitInfo.SkillParam;
        //浮空数值
        var flowSpeed = new Vector3(param.flowSpeed.x, param.flowSpeed.y,
            param.flowSpeed.z * GameRandom.RollSymbol(0.5f));
        var rot = Quaternion.FromToRotation(Vector3.right, hitInfo.HitDir);
        flowSpeed = rot * flowSpeed;

        if (hitInfo.IsBreak)
        {
            //近距离推开
            //根据实体xz距离调整xz浮空速度，距离为0时系数为1.5，距离大于0.5时系数为1
            var flowSpeedXZ = new Vector3(flowSpeed.x, 0, flowSpeed.z);
            var dist = Util.EntityDistanceXZ(entity, target);
            flowSpeedXZ *= Mathf.Clamp(1.5f - dist, 1, 2);
            flowSpeed = new Vector3(flowSpeedXZ.x, flowSpeed.y, flowSpeedXZ.z);
        }

        if (hitLevel >= EHitLevel.Flowing)
        {
            target.move.IsFlowing = true;
        }
        else
        {
            flowSpeed = new Vector3(flowSpeed.x, 0, flowSpeed.z);
        }

        //根据命中等级调整系数
        switch (hitLevel)
        {
            case EHitLevel.Block:
                flowSpeed *= 0.2f;
                break;
            case EHitLevel.Stagger1:
                flowSpeed *= 0.7f;
                break;
            case EHitLevel.Stagger2:
                flowSpeed *= 1f;
                break;
            case EHitLevel.Stagger3:
                flowSpeed *= 1.2f;
                break;
        }

        //记录受击方向 添加强制移动buff
        if (flowSpeed != Vector3.zero)
        {
            target.hp.LastDamageDir = flowSpeed;
            if (flowSpeed.y < 0)
            {
                //击落
                Util.AddHitDownBuff(target.ID());
            }

            //击退
            Util.AddSetSpeedBuff(target.ID(), param.flowTime);
        }

        target.hp.LastDamageLevel = hitLevel;

        //命中瞬间、在pause之前生效部分位移
        var move = target.move;
        var posAdd = flowSpeed * Time.deltaTime * 2;
        var targetPos = move.Position + posAdd;
        var startPos = move.Position - posAdd.normalized * 0.001f;
        RaycastHit raycastHit;
        if (Physics.Raycast(startPos, posAdd, out raycastHit, posAdd.magnitude, UtilPhysics.LayerMaskStatic))
        {
            targetPos = raycastHit.point;
        }

        Util.SetEntityPos(target, targetPos);

        return flowSpeed;
    }

    private static float SettlePause(SkillHitInfo hitInfo, EHitLevel hitLevel, GameEntity entity, GameEntity target)
    {
        if (target.IsMaster())
        {
            //主角受击不卡帧
            return 0f;
        }

        var param = hitInfo.SkillParam;
        var pauseTime = 1f * param.pauseTime / GameConst.FPS;

        if (hitLevel >= EHitLevel.ShieldBreak)
        {
            pauseTime = Mathf.Max(pauseTime, 0.05f);
            //受击方向
            var dir = target.hp.LastDamageDir;
            //受击方向与实体方向夹角
            var angle = Vector3.Angle(dir, target.move.Transform.forward);
            //夹角越大，卡帧越长
            pauseTime *= Mathf.Clamp(1.5f - angle / 180, 0.5f, 1);
        }

        //根据命中等级调整系数
        switch (hitLevel)
        {
            case EHitLevel.ShieldBreak:
                pauseTime *= 1.5f;
                break;
            case EHitLevel.Block:
                pauseTime *= 1.2f;
                break;
            case EHitLevel.Kill:
                pauseTime *= 1.5f;
                break;
        }

        //单次攻击命中多目标:每2帧结算一次
        var isLastHit = hitInfo.HitIndex == hitInfo.HitCount - 1;
        if (isLastHit)
            Util.EntityPause(entity, pauseTime, false);
        else
            Util.EntityPause(entity, 1f / GameConst.FPS, false);
        Util.EntityPause(target, pauseTime);
        return pauseTime;
    }

    private static void SettleSelfMoveForceScale(EHitLevel hitLevel, GameEntity entity, GameEntity target)
    {
        switch (hitLevel)
        {
            case EHitLevel.Stagger1:
            case EHitLevel.Stagger2:
            case EHitLevel.Stagger3:
                Util.EntitySetTempMoveForceScale(entity.ID(), -0.8f);
                break;
            case EHitLevel.Block:
                Util.EntitySetTempMoveForceScale(entity.ID(), -1.2f);
                break;
        }
    }

    private static void SettleBreak(Vector3 flowSpeed, EHitLevel hitLevel, SettleDamageResult dmgResult,
        GameEntity entity, GameEntity target)
    {
        //打断技能
        if (hitLevel > EHitLevel.Block)
        {
            Util.EndSkillTimeline(target);
        }

        //强制转向
        if (hitLevel > EHitLevel.Stagger2)
        {
            Util.EntityTurn(target, flowSpeed.x < 0);
        }

        //受击动画
        if (dmgResult.IsFlowing)
        {
            if (hitLevel > EHitLevel.Block)
            {
                target.animation.AirHitMsg = true;
            }
        }
        else
        {
            if (Util.HasStunBuff(target.ID()))
            {
                if (hitLevel > EHitLevel.Stun)
                    target.animation.AirHitMsg = true;
                else if (hitLevel > EHitLevel.Block)
                    target.animation.StunHitMsg = true;
            }
            else
            {
                switch (hitLevel)
                {
                    case EHitLevel.Stagger1:
                        target.animation.HitMsg = true;
                        break;
                    case EHitLevel.Stagger2:
                        target.animation.MHitMsg = true;
                        break;
                    case EHitLevel.Stagger3:
                        target.animation.LHitMsg = true;
                        break;
                    case EHitLevel.ShieldBreak:
                    case EHitLevel.Stun:
                        target.animation.StunHitMsg = true;
                        break;
                    case EHitLevel.Flowing:
                    case EHitLevel.Kill:
                        target.animation.AirHitMsg = true;
                        break;
                }
            }
        }
    }

    private static void SettleBuff(EHitLevel hitLevel, GameEntity entity, GameEntity target)
    {
        switch (hitLevel)
        {
            case EHitLevel.Stagger1:
                Util.AddStaggerBuff(target.ID(), 0.2f);
                break;
            case EHitLevel.Stagger2:
                Util.AddStaggerBuff(target.ID(), 0.5f);
                break;
            case EHitLevel.Stagger3:
                Util.AddStaggerBuff(target.ID(), 1f);
                break;
            case EHitLevel.Flowing:
                Util.AddStaggerBuff(target.ID(), -1f);
                break;
            case EHitLevel.ShieldBreak:
            case EHitLevel.Stun:
                Util.AddStunBuff(target.ID());
                break;
        }
    }

    private static void SettleTrigger(SkillHitInfo hitInfo, GameEntity entity, GameEntity target)
    {
        //触发buffTrigger
        UtilBuff.BuffEffectAll(target.ID(), EBuffEffectTimingType.BeAttack);

        //触发SkillTrigger
        UtilSkillTrigger.Trigger(entity.ID(), target.ID(), hitInfo.SkillId, ESkillTriggerTimingType.Hit);
    }

    private static void SettleHitText(EHitLevel hitLevel, SettleDamageResult dmgResult, GameEntity entity,
        GameEntity target)
    {
        //受击事件广播
        var hitMsg = new PEntityHit()
        {
            Entity = entity.ID(),
            Target = target.ID(),
            Dmg = (int)dmgResult.Damage,
            IsSkill = dmgResult.IsSkill,
        };
        EventManager.Instance.SendEvent<PEntityHit>(EEvent.EntityHit, hitMsg);
        switch (hitLevel)
        {
            case EHitLevel.ShieldBreak:
                //破盾事件广播
                var breakmsg = new PEntityHitText()
                {
                    Target = target.ID(),
                    Text = "Break",
                };
                EventManager.Instance.SendEvent<PEntityHitText>(EEvent.EntityHitText, breakmsg);
                break;
            // case EHitLevel.Block:
            //     //格挡事件广播
            //     var blockmsg = new PEntityHitText()
            //     {
            //         target = target.ID(),
            //         text = "Block",
            //     };
            //     EventManager.instance.SendEvent<PEntityHitText>(EEvent.EntityHitText, blockmsg);
            //     break;
            // default:
            //     //测试
            //     var msg = new PEntityHitText()
            //     {
            //         target = target.ID(),
            //         text = hitLevel.ToString(),
            //     };
            //     EventManager.instance.SendEvent<PEntityHitText>(EEvent.EntityHitText, msg);
            //     break;
        }
    }

    private static void SettleHitEffect(Vector3 flowSpeed, EHitLevel hitLevel, EHitType hitType, GameEntity entity,
        GameEntity target)
    {
        //受击特效
        var effectRot = GameRandom.RandomRot(Util.Vec3ToRot(new Vector3(flowSpeed.x, 0, flowSpeed.y)), 45);
        switch (hitLevel)
        {
            case EHitLevel.Kill:
                Util.CastHitEffect(GameConst.EffectHitKill, target.ID(), effectRot);
                break;
            case EHitLevel.ShieldBreak:
                Util.CastHitEffect(GameConst.EffectHitShieldBreak, target.ID(), effectRot);
                break;
            case EHitLevel.Block:
                Util.CastHitEffect(GameConst.EffectHitShield, target.ID(), effectRot);
                break;
            default:
                switch (hitType)
                {
                    case EHitType.Slash:
                        Util.CastHitEffect(GameConst.EffectHitSlash, target.ID(), effectRot);
                        break;
                    case EHitType.Blunt:
                        Util.CastHitEffect(GameConst.EffectHitBlunt, target.ID(), effectRot);
                        break;
                    default:
                        Util.CastHitEffect(GameConst.EffectHitSlash, target.ID(), effectRot);
                        break;
                }

                break;
        }
    }

    private static void SettleFlash(EHitLevel hitLevel, GameEntity entity, GameEntity target)
    {
        switch (hitLevel)
        {
            case EHitLevel.ShieldBreak:
                Util.EntityFlash(target, Color.red);
                break;
            case EHitLevel.Block:
                Util.EntityFlash(target, Color.yellow);
                break;
            default:
                Util.EntityFlash(target);
                break;
        }
    }

    private static void SettleShake(EHitLevel hitLevel, GameEntity entity, GameEntity target)
    {
        Util.EntityShake(target, 3);
        Util.EntityShake(entity, 1);
    }

    private static void SettleScale(Vector3 flowSpeed, GameEntity entity, GameEntity target)
    {
        var dir = new Vector3(flowSpeed.x * (target.move.IsRight ? 1 : -1), flowSpeed.y, 0);
        Util.EntityScale(target, dir);
    }

    private static void SettleGlobalEffect(GameEntity target, float pauseTime)
    {
        if (target.IsMaster())
        {
            //主角受击
            Util.SetTimeScaleEffect(0.2f, 1, 0.5f);
            Util.SetAberrationEffect(1, 0, 0.5f);
            Util.SetFovEffect(0.9f, 1, 0.5f);
            return;
        }

        if (pauseTime >= 0.1f)
        {
            Util.Shake();

            var (aberrationFrom, aberrationTo) = (0.5f, 0);
            var (timeScaleFrom, timeScaleTo) = (0.2f, 1);
            var (fovFrom, fovTo) = (0.85f, 1);
            var effectTime = pauseTime + 0.2f;

            Util.SetAberrationEffect(aberrationFrom, aberrationFrom, pauseTime);
            Util.AppendAberrationEffect(aberrationFrom, aberrationTo, 0.3f);

            // Util.SetTimeScaleEffect(timeScaleFrom, timeScaleFrom, pauseTime);
            // Util.AppendTimeScaleEffect(timeScaleFrom, timeScaleTo, 0.5f);

            Util.SetFovEffect(fovFrom, fovFrom, pauseTime);
            Util.AppendFovEffect(fovFrom, fovTo, 0.5f);
        }
        else if (pauseTime > 0)
        {
            Util.SetAberrationEffect(0.2f, 0, 0.2f);
            Util.SetFovEffect(0.99f, 1, 0.2f);
        }
        else
        {
            Util.SetAberrationEffect(0.2f, 0, 0.2f);
            Util.SetFovEffect(0.99f, 1, 0.2f);
        }
    }
}