using System;
using DragonLi.Core;
using DragonLi.Frame;
using UnityEngine;

public class ShieldProjectile : MonoBehaviour
{
    public enum State { Idle, FlyingOut, Grounded, Returning }

    [Header("配置参数")]
    public Transform playerTransform;
    public Transform bossHandTransform;
    public float flySpeed = 10f;
    public float groundY = 0.5f;
    public float stayDuration = 2f;
    private float hitRadius = 4f;
    public float damageAmount = 20f;

    private State currentState = State.Idle;
    private float stayTimer = 0f;
    private bool hasHitPlayerThisPhase = false;

    // —— 新增：飞行方向目标位置（固定） ——
    private Vector3 fixedTargetPosition;

    // 声明回调事件
    public event Action OnReturnComplete;


    public void Initialize(Transform player, Transform bossHand, float speed, float groundYPos, float stayTime, float radius, float dmg)
    {
        playerTransform = player;
        bossHandTransform = bossHand;
        flySpeed = speed;
        groundY = groundYPos;
        stayDuration = stayTime;
        hitRadius = radius;
        damageAmount = dmg;

        // 在发射瞬间记录玩家位置，后续“飞行”只对这个位置做插值
        fixedTargetPosition = playerTransform.position.ReflectVectorXOZ();

        currentState = State.FlyingOut;
        hasHitPlayerThisPhase = false;
        stayTimer = 0f;

        // 初始化位置为 Boss 手部
        transform.position = bossHandTransform.position;
    }

    private void Update()
    {
        switch (currentState)
        {
            case State.FlyingOut:
                FlyOut();
                break;
            case State.Grounded:
                HandleGrounded();
                break;
            case State.Returning:
                FlyBack();
                break;
        }
    }

    private void FlyOut()
    {
        // —— 修改：不再动态追踪 playerTransform.position，而是朝 fixedTargetPosition 飞 —— 
        Vector3 dir = (fixedTargetPosition - transform.position).normalized;
        transform.position += dir * flySpeed * Time.deltaTime;

        // 距离检测仍用实时玩家位置
        if (!hasHitPlayerThisPhase)
        {
            float sqrDist = Vector3.Distance(transform.position,playerTransform.position);
            if (sqrDist <= hitRadius)
            {
                HitPlayer();
                hasHitPlayerThisPhase = true;
            }
        }

        // 到达或低于地面高度时，切入 Grounded
        if (transform.position.y <= groundY)
        {
            Vector3 pos = transform.position;
            pos.y = groundY;
            transform.position = pos;

            currentState = State.Grounded;
            hasHitPlayerThisPhase = false;
            stayTimer = 0f;
        }
    }

    private void HandleGrounded()
    {
        stayTimer += Time.deltaTime;
        if (!hasHitPlayerThisPhase)
        {
            float sqrDist = Vector3.Distance(transform.position,playerTransform.position);
            if (sqrDist <= hitRadius)
            {
                HitPlayer();
                hasHitPlayerThisPhase = true;
            }
        }
        if (stayTimer >= stayDuration)
        {
            currentState = State.Returning;
            hasHitPlayerThisPhase = false;
        }
    }

    private void FlyBack()
    {
        Vector3 dir = (bossHandTransform.position - transform.position).normalized;
        transform.position += dir * flySpeed * Time.deltaTime;

        if (!hasHitPlayerThisPhase)
        {
            float sqrDist = (transform.position - playerTransform.position).sqrMagnitude;
            if (sqrDist <= hitRadius * hitRadius)
            {
                HitPlayer();
                hasHitPlayerThisPhase = true;
            }
        }

        if ((transform.position - bossHandTransform.position).sqrMagnitude <= 0.01f)
        {
            OnReturnComplete?.Invoke();
            Destroy(gameObject);
        }
    }

    private void HitPlayer()
    {
        var ph = playerTransform.GetComponent<IDamagable>();
        if (ph != null)
            ph.ApplyDamage(damageAmount,null,transform);
    }
}