using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using UnityEngine.AI;

public class Yeji : TargetAnimal
{
    //动画播放器
    AnimationPlayer ap;
    //寻路代理
    NavMeshAgent agent;
    //血量
    [System.NonSerialized] public int hp = 3;
    public TreeAreaRecorder treeAreaRecorder;
    //模型的偏移Y（即坐标为Zero时，模型超出地面的高度）
    public const float modelOffsetY = 0.33f;
    [System.NonSerialized] public float flyPlaneHeight = 5;
    public void SetFlyHeight(float value) {
        float agentBaseOffset = value - flyPlaneHeight - modelOffsetY;
        this.agent.baseOffset = agentBaseOffset / 2;
    }

    void Awake()
    {
        ap = GetComponent<AnimationPlayer>();
        agent = GetComponent<NavMeshAgent>();
    }

    void Start()
    {
        //初始动画
        playAniFly();
        //初始化自动策略
        InitAutoStrategy();
    }

    void Update()
    {
        //寻路过程监测
        if (HasCloseToDestination()) {
            OnReachDestination();
        } else {
            OnMovingToDestination();
        }
        UpdateAction();
        UpdateActionTime();
        UpdateAutoStrategy();
        if (Input.GetKeyDown(KeyCode.S)) {
            
        }
    }

    public void Disappear() {
        Destroy(this.gameObject);
    }

    public override void OnHit(Arrow arrow, Vector3 hitPoint, string partName)
    {
        arrow.Head().position = hitPoint + arrow.transform.forward * 0.1f;
        arrow.Hit();
        if (partName == "Wing") {
            hp -= 1;
            this.agent.speed /= 2f;
        }
        else if (partName == "Body") hp -= 2;
        else if (partName == "Head") hp -= 3;
        if (hp <= 0) {
            Die(arrow);
        } else {
            Hurt();
        }
    }

    void Die(Arrow arrow) {
        if (dead) return;
        arrow.onDoNextShoot += delegate() {
            Disappear();
        };
        dead = true;
        this.agent.enabled = false;
        PuaseAutoStrategy();
        onDie?.Invoke(this);
        AudioMgr.ins.PlayAnimalEffect("bird_die", AudioMgr.GetAudioSource(this.gameObject));
    }

    void Hurt() {
        AudioMgr.ins.PlayAnimalEffect("bird_injured", AudioMgr.GetAudioSource(this.gameObject));
    }

    //是否已经死亡
    bool dead = false;
    //是否处于移动状态
    bool _moving = false;
    bool moving {
        get {
            return _moving;
        }
        set {
            if (_moving && !value) {
                movingTime = 0;

            }
            if (!_moving && value) stayingTime = 0;
            _moving = value;
        }
    }
    //实时记录“单次移动的持续时间”
    float movingTime = 0;
    //实时停留时间
    float stayingTime = 0;
    //启动寻路
    void SetDestination(Vector3 pos) {
        moving = true;
        this.agent.destination = pos;
    }
    //寻路过程
    void OnMovingToDestination() {
        if (!moving) return;
    }
    //寻路结束
    void OnReachDestination() {
        if (!moving) return;
        moving = false;
    }
    //是否已经接近目的地（寻路完成判断）
    bool HasCloseToDestination() {
        if (!moving) return true;
        if (movingTime > 0.1) {
            if (this.agent.velocity.magnitude < 0.05f) {
                return true;
            }
        }
        return false;
    }
    //更新动作
    void UpdateAction() {
        if (dead) {
            if (!isAniDie()) playAniDie();
        } else {
            if (!isAniFly()) playAniFly();
        }
    }
    //记录动作时间
    void UpdateActionTime() {
        if (moving) {
            movingTime += Time.deltaTime;
        } else {
            stayingTime += Time.deltaTime;
        }
    }

    float willStayTime;
    float willMoveTime;  
    bool autoMoving = false;
    float autoMovingTime;
    bool autoStrategy = true;
    //自动策略的更新逻辑
    void UpdateAutoStrategy() {
        if (!autoStrategy) return;
        if (stayingTime > willStayTime) {
            autoMoving = true;
            RandomMove();
            RandomWillStayTime();
        } 
        if (autoMoving) {
            if (moving) {
                autoMovingTime += Time.deltaTime;
            } else if (autoMovingTime < willMoveTime) {
                RandomMove();
            } else if (autoMovingTime >= willMoveTime) {
                Stay();
                RandomWillMoveTime();
                autoMoving = false;
                autoMovingTime = 0;
            }
        }
    }
    void InitAutoStrategy() {
        autoStrategy = true;
        this.willStayTime = 1;
        RandomWillMoveTime();
    }
    void PuaseAutoStrategy() {
        this.autoStrategy = false;
    }
    void ResumeAutoStrategy() {
        this.autoStrategy = true;
        RandomWillStayTime();
        RandomWillMoveTime();
        this.autoMoving = false;
        this.autoMovingTime = 0;
    }
    void RandomWillStayTime() {
        this.willStayTime = 1;
    }
    void RandomWillMoveTime() {
        this.willMoveTime = 20;
    }

    //逃跑远离猎人
    void RunAwayFromHunter() 
    {
        Vector3 backVec = GetPointerHunterToMe();
        SetDestination(transform.position + backVec.normalized * 5);
    }
    
    //能够在前几棵树徘徊
    [System.NonSerialized] public int canFlyTreeCount = 4;
    //将会绕树转
    bool willMoveRoundTree = false;
    Queue<Vector3> roundTreePostions = new Queue<Vector3>();
    //随机移动
    void RandomMove() {
        if (willMoveRoundTree && roundTreePostions.Count > 0) {
            Vector3 pos = roundTreePostions.Dequeue();
            SetDestination(pos);
            return;
        } else {
            willMoveRoundTree = false;
        }
        Vector3 myPos = this.transform.position; 
        TreeAreaRecorder.AreaInfo[] areaInfos = treeAreaRecorder.copyAreaInfos(canFlyTreeCount); 
        for (int i = 0; i < canFlyTreeCount; i++) {
            areaInfos[i].teamCompareValue = areaInfos[i].distanceInHorizontal(myPos);
        }
        System.Array.Sort(areaInfos, new ComparerAreaInfosByDistance());
        //如果离这棵树比较近，有几率使其绕着树转
        TreeAreaRecorder.AreaInfo firstAreaInfo = areaInfos[0];
        bool isNearTree4th = areaInfos.Length == 4 && firstAreaInfo == treeAreaRecorder.getValidAreaInfo(3);
        if (!isNearTree4th && firstAreaInfo.teamCompareValue < firstAreaInfo.radius + 1.5f && Random.value < 0.5) {
            willMoveRoundTree = true;
            Vector3 treePos = areaInfos[0].transform.position; 
            treePos.y = myPos.y;
            Vector3 pointer = myPos - treePos;
            roundTreePostions.Clear();
            int direction = Random.value >= 0.5 ? 1 : -1;
            for (int i = 1; i <= 6; i++) {
                roundTreePostions.Enqueue(treePos + Quaternion.AngleAxis(i * 60 * direction, Vector3.up) * pointer);
            }
            RandomMove();
            return;
        }
        TreeAreaRecorder.AreaInfo areaInfo = areaInfos[Random.Range(1, canFlyTreeCount)];
        Vector3 newPos = YejiHuntGameMode.CalculateNewPosByTreePos(animalsBaseT, flyPlaneHeight, areaInfo);
        SetDestination(newPos);
    }

    class ComparerAreaInfosByDistance : IComparer {
        public int Compare(object x, object y) {
            TreeAreaRecorder.AreaInfo a = (TreeAreaRecorder.AreaInfo)x;
            TreeAreaRecorder.AreaInfo b = (TreeAreaRecorder.AreaInfo)y;
            if (a.teamCompareValue - b.teamCompareValue > 0) return 1;
            if (a.teamCompareValue - b.teamCompareValue < 0) return -1;
            else return 0;
        }
    }

    //停留
    void Stay() {
        if (moving) {
            this.agent.destination = this.agent.nextPosition;
            OnReachDestination();
        }
    }

    //当前动画索引
    int curAnimIndex = 0;
    void playAniDie() {
        ap.play(curAnimIndex = 1, WrapMode.Once);
    }
    bool isAniDie() {
        return curAnimIndex == 1;
    }
    void playAniFly() {
        ap.play(curAnimIndex = 0, WrapMode.Loop);
    }
    bool isAniFly() {
        return curAnimIndex == 0;
    }

    //委托
    public System.Action<Yeji> onDie;
}