using UnityEngine;
using UnityEngine.AI;
using System.Collections; // ⭐ IEnumerator 사용을 위해 추가
using System;

public class MonsterClass : MonoBehaviour, IDamageable
{
    [Header("스탯")]
    [SerializeField] protected float maxHP = 100f;
    protected float currentHP;
    public event Action<float, float> OnHealthChanged;

    [Header("피격 / 사망 애니메이션")]
    [SerializeField] protected string Monster_GetDamage = "Monster_GetDamage";
    [SerializeField] protected string Monster_Die = "Monster_Die";

    protected Animator animator;
    protected NavMeshAgent agent;
    protected AudioSource audioSource;
    protected bool isHit;
    protected bool isDead;
    protected bool isAttacking;

    [Header("AI 설정 (공격 후 휴식)")]
    [SerializeField] protected float attackRestDuration = 1.5f; // ⭐ 공격 후 쉬는 시간 (초)
    protected bool isResting; // ⭐ 현재 쉬고 있는 상태인지 확인

    [Header("경험치")]
    [SerializeField] protected int expReward = 10;
    public static System.Action<int> OnMonsterKilled;

    [Header("공통 사운드/이펙트")]
    [SerializeField] protected AudioClip hitSound;
    [SerializeField] protected AudioClip deathSound;
    [SerializeField] protected GameObject deathEffectPrefab;
    [SerializeField] protected ParticleSystem hitEffect;
    [SerializeField] protected Transform impactSpawnPoint;

    [Header("--- 드랍 설정 ---")]
    [SerializeField] private GameObject potionPrefab;
    [SerializeField][Range(0f, 100f)] private float potionDropChance = 30f;
    [Space(10)]
    [SerializeField] private GameObject[] weaponPrefabs;
    [SerializeField][Range(0f, 100f)] private float weaponDropChance = 5f;

    protected virtual void Start()
    {
        currentHP = maxHP;
        animator = GetComponent<Animator>();
        agent = GetComponent<NavMeshAgent>();
        audioSource = GetComponent<AudioSource>();
        OnHealthChanged?.Invoke(currentHP, maxHP);
    }

    protected virtual void Update()
    {
        if (isDead) return;

        // ⭐ [수정] 피격(isHit), 공격(isAttacking), 또는 휴식(isResting) 중이면 이동을 멈춥니다.
        bool shouldStop = isHit || isAttacking || isResting;

        if (agent != null && agent.isOnNavMesh)
        {
            agent.isStopped = shouldStop;
            if (shouldStop) agent.velocity = Vector3.zero;
        }

        if (animator != null)
        {
            // 멈췄을 때는 속도를 0으로 전달하여 Idle 애니메이션이 나오게 합니다.
            float currentSpeed = (agent != null && !shouldStop) ? agent.velocity.magnitude : 0f;
            animator.SetFloat("Speed", currentSpeed);
        }
    }

    public virtual void TakeDamage(float amount) { OnDamaged(amount); }

    public virtual void OnDamaged(float damage)
    {
        if (isDead) return;
        currentHP -= damage;
        OnHealthChanged?.Invoke(currentHP, maxHP);

        if (currentHP <= 0) { Die(); return; }
        if (!isHit) StartHit();
    }

    protected virtual void StartHit()
    {
        isHit = true;
        isAttacking = false;
        isResting = false; // ⭐ 맞으면 쉬는 걸 중단하고 바로 아파해야 합니다.
        StopAllCoroutines(); // 진행 중인 휴식 루틴을 끕니다.

        if (agent && agent.isOnNavMesh) { agent.isStopped = true; agent.velocity = Vector3.zero; }

        animator.Play(Monster_GetDamage, 0, 0f);
        if (hitEffect) hitEffect.Play();
        if (hitSound) audioSource.PlayOneShot(hitSound);
    }

    public virtual void OnAttackStart() { isAttacking = true; isResting = false; }

    // ⭐ [수정] 공격이 끝나면 바로 움직이는 게 아니라 '휴식' 코루틴을 실행합니다.
    public virtual void OnAttackEnd()
    {
        isAttacking = false;
        if (!isDead && !isHit)
        {
            StartCoroutine(RestAfterAttack());
        }
    }

    // ⭐ 공격 후 대기 코루틴
    private IEnumerator RestAfterAttack()
    {
        isResting = true;
        yield return new WaitForSeconds(attackRestDuration); // 설정한 시간만큼 대기
        isResting = false;
    }

    public virtual void OnHitEnd() { isHit = false; if (agent && agent.isOnNavMesh) agent.isStopped = false; }

    protected virtual void Die()
    {
        if (isDead) return;
        isDead = true;

        Collider col = GetComponent<Collider>();
        if (col != null) col.enabled = false;

        OnMonsterKilled?.Invoke(expReward);
        TryDropItems();

        if (agent && agent.isOnNavMesh) { agent.isStopped = true; agent.velocity = Vector3.zero; }
        animator.Play(Monster_Die, 0, 0f);
        if (deathSound) audioSource.PlayOneShot(deathSound);

        Destroy(gameObject, 1.5f);
    }

    private void TryDropItems()
    {
        if (potionPrefab != null && UnityEngine.Random.Range(0f, 100f) <= potionDropChance) SpawnItem(potionPrefab);
        if (weaponPrefabs != null && weaponPrefabs.Length > 0 && UnityEngine.Random.Range(0f, 100f) <= weaponDropChance)
        {
            int randomIndex = UnityEngine.Random.Range(0, weaponPrefabs.Length);
            SpawnItem(weaponPrefabs[randomIndex]);
        }
    }

    private void SpawnItem(GameObject prefab)
    {
        Vector3 spawnPos = transform.position + Vector3.up * 0.5f;
        GameObject item = Instantiate(prefab, spawnPos, Quaternion.identity);
        item.transform.localScale = prefab.transform.localScale;

        if (item.TryGetComponent<Rigidbody>(out var rb))
        {
            Vector3 popDir = Vector3.up * 0.02f + UnityEngine.Random.insideUnitSphere * 0.02f;
            rb.AddForce(popDir, ForceMode.Impulse);
            if (prefab != potionPrefab) rb.AddTorque(UnityEngine.Random.insideUnitSphere * 0.3f, ForceMode.Impulse);
        }
    }

    public void OnDeathAnimEnd() { }
}