using UnityEngine;
using Platformer.Mechanics;

namespace EerieVillage.Skills.Effectors
{
    /// <summary>
    /// 유도 투사체. A15 추적 화염구 전용.
    /// Projectile 파생 — Update를 FixedUpdate 기반 방향 보정으로 확장.
    /// BT12-Dev Phase 2-B §4-3.
    /// </summary>
    public class HomingProjectile : Projectile
    {
        private Transform _target;
        private float _homingStrength = 5f;

        public override void Initialize(ActiveSkillRuntime runtime, PlayerSkillInventory inventory, Vector2 direction)
        {
            base.Initialize(runtime, inventory, direction);
            _target = FindNearestEnemy();
        }

        protected override void Update()
        {
            // 타겟 갱신 (사망·삭제 시 재탐색)
            if (_target == null || !_target.gameObject.activeInHierarchy)
            {
                _target = FindNearestEnemy();
            }

            if (_target != null)
            {
                Vector2 toTarget = ((Vector2)_target.position - (Vector2)transform.position).normalized;
                _direction = Vector2.Lerp(_direction, toTarget, _homingStrength * Time.deltaTime).normalized;
            }

            // 부모 Update — 실제 이동
            base.Update();
        }

        private Transform FindNearestEnemy()
        {
            var enemies = Object.FindObjectsByType<EnemyController>(FindObjectsSortMode.None);
            Transform nearest = null;
            float minDist = float.MaxValue;

            foreach (var e in enemies)
            {
                if (e == null) continue;
                var hp = e.GetComponent<Health>();
                if (hp == null || !hp.IsAlive) continue;

                float d = Vector2.Distance(transform.position, e.transform.position);
                if (d < minDist)
                {
                    minDist = d;
                    nearest = e.transform;
                }
            }

            return nearest;
        }
    }
}