EerieVillage/Assets/Scripts/Skills/Effectors/PiercingProjectile.cs

using System.Collections.Generic;
using UnityEngine;
using Platformer.Mechanics;
using Platformer.Gameplay;
using static Platformer.Core.Simulation;

namespace EerieVillage.Skills.Effectors
{
    /// <summary>
    /// A13 천둥발 변경 컨셉 (PD 지시 2026-05-13).
    /// FX_Lightningball 투사체 — 천천히 전진·관통·경로 닿는 적 매 0.2초마다 영역 데미지.
    ///
    /// 기존 Projectile 와 다름:
    ///   - 적 명중 후 SelfDestruct X (관통)
    ///   - 각 적별 마지막 tick 시각 추적·DotInterval (0.2s) 영역 영역 데미지
    /// </summary>
    public class PiercingProjectile : Projectile
    {
        // 적별 마지막 hit 시각
        readonly Dictionary<EnemyController, float> _lastHitTime = new Dictionary<EnemyController, float>();

        public override void Initialize(ActiveSkillRuntime runtime, PlayerSkillInventory inventory, Vector2 direction)
        {
            base.Initialize(runtime, inventory, direction);
            _speed = 2.5f;  // PD 지시 2026-05-13 — A13 천둥발 천천히 전진 (기본 6 → 2.5)
            _lifetime = 6f;  // 관통이므로 lifetime 길게
            _lastHitTime.Clear();

            // PD 정합 2026-05-13 — OnTriggerStay2D 발화 영역 Kinematic Rigidbody2D + useFullKinematicContacts 영역
            // Enemy 영역 Kinematic Rb → Kinematic vs Kinematic OnTriggerStay2D 영역 기본 발화 X.
            // useFullKinematicContacts=true 영역 영역 발화 정합.
            var rb = GetComponent<Rigidbody2D>();
            if (rb == null) rb = gameObject.AddComponent<Rigidbody2D>();
            rb.bodyType = RigidbodyType2D.Kinematic;
            rb.simulated = true;
            rb.gravityScale = 0f;
            rb.useFullKinematicContacts = true;
        }

        // PD 정합 2026-05-13 — OnTrigger 영역 폐기 (Kinematic vs Kinematic 발화 영역 영역 X).
        // Update 영역 OverlapBox 영역 매 frame 직접 검사·적별 0.2s 간격 영역 (다른 액티브 정합).
        protected override void OnTriggerEnter2D(Collider2D other) { /* no-op */ }

        protected override void Update()
        {
            base.Update();  // 이동·페이드·SyncHitboxToData

            if (_data == null) return;
            float interval = (_data.DotInterval > 0.01f) ? _data.DotInterval : 0.2f;
            float now = Time.time;

            var cf = new ContactFilter2D();
            cf.useTriggers = false;
            int enemyLayer = LayerMask.NameToLayer("Enemy");
            if (enemyLayer >= 0) { cf.SetLayerMask(1 << enemyLayer); cf.useLayerMask = true; }
            var results = new Collider2D[16];
            // 박스 영역 transform.position + collider.size × localScale 영역 정합
            var box = GetComponent<BoxCollider2D>();
            Vector2 worldSize = box != null
                ? new Vector2(box.size.x * Mathf.Abs(transform.lossyScale.x), box.size.y * Mathf.Abs(transform.lossyScale.y))
                : (Vector2)_data.HitboxSize;
            int n = Physics2D.OverlapBox(transform.position, worldSize, transform.eulerAngles.z, cf, results);
            int damage = Mathf.Max(_data.BaseDamage, 1);
            for (int i = 0; i < n; i++)
            {
                var c = results[i];
                if (c == null) continue;
                var enemy = c.GetComponent<EnemyController>();
                if (enemy == null) continue;
                var health = c.GetComponent<Health>();
                if (health == null || !health.IsAlive) continue;

                float last;
                if (_lastHitTime.TryGetValue(enemy, out last))
                {
                    if (now - last < interval) continue;
                }
                _lastHitTime[enemy] = now;

                health.DecrementBypassInvulnWithHit(damage);
                if (!health.IsAlive)
                {
                    Schedule<EnemyDeath>().enemy = enemy;
                }
            }
        }
    }
}