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

namespace EerieVillage.Skills.Effectors
{
    /// <summary>
    /// A05 학익진 — 플레이어 주변 범위 즉시 피해 + FX_SLASH 이펙트.
    /// PD 지시 (2026-05-13):
    ///   - 1.5초 간격 (BaseCooldown 1.5)
    ///   - 플레이어 주변 영역 (HitboxSize 반경) 내 적에게 피해
    ///   - 공격력 10 (BaseDamage)
    ///   - FX_SLASH 이펙트 재생 (data.OnHitFxPrefab)
    /// </summary>
    public class MeleeAreaSpawner : IEffector
    {
        public void Trigger(ActiveSkillRuntime runtime, PlayerSkillInventory inventory)
        {
            var data = runtime.ActiveData;
            // PD 지시 2026-05-13 — OffsetDistanceX = X 절대·OffsetDistance = Y 절대·OffsetXY = 이펙트만
            Vector2 playerPos = inventory.transform.position;
            Vector2 fxPos = playerPos + data.OffsetXY;

            Vector2 facing = Vector2.right;
            var pc = inventory.GetComponent<PlayerController>();
            if (pc != null) facing = pc.Facing;

            // 이펙트 spawn — fxPos·HitFxScale·FxRotation·facing flip
            GameObject fxGo = null;
            float fxLifetime = 1f;
            if (data.OnHitFxPrefab != null)
            {
                fxGo = Object.Instantiate(data.OnHitFxPrefab, fxPos, Quaternion.Euler(0f, 0f, data.FxRotation));
                fxGo.hideFlags = HideFlags.DontSave;  // PD 지시 2026-05-13 — Scene 저장 회피
                Vector3 s = fxGo.transform.localScale * data.HitFxScale;
                if (facing.x < 0f) s.x = -Mathf.Abs(s.x);
                fxGo.transform.localScale = s;
                // PD 지시 2026-05-13 — 좌우 베기 이펙트가 Player 이동 시 뒤로 밀리는 현상 정정.
                // Player 자식 부착 (worldPositionStays=true) 으로 spawn 후에도 Player 이동에 동조.
                fxGo.transform.SetParent(inventory.transform, true);
                fxLifetime = GetFxLifetime(fxGo);
                // PD 지시 2026-05-13 — FX 잔상 safety cap 5초
                Object.Destroy(fxGo, Mathf.Min(fxLifetime + 0.2f, 5f));
            }

            // PD 지시 2026-05-13 — 박스 영역 Player 자식 영역 부착·매 frame Player 따라감
            Vector2 hitboxSize = data.HitboxSize;
            int damage = Mathf.Max(runtime.CalculateEffectiveDamage(), data.BaseDamage);
            float duration = Mathf.Max(data.BaseCooldown, 1f);

            var boxGo = new GameObject("MeleeHitbox_Debug");
            boxGo.hideFlags = HideFlags.DontSave;
            boxGo.transform.SetParent(inventory.transform, false);
            float lpx = inventory.transform.lossyScale.x != 0f ? Mathf.Abs(inventory.transform.lossyScale.x) : 1f;
            float lpy = inventory.transform.lossyScale.y != 0f ? Mathf.Abs(inventory.transform.lossyScale.y) : 1f;
            // PD 지시 2026-05-13 — 박스(판정) = facing 좌/우 sign 만 반영 · FxRotation 미적용 (시각 전용)
            float signX = facing.x < 0f ? -1f : 1f;
            boxGo.transform.localPosition = new Vector3(signX * data.OffsetDistance.x / lpx, data.OffsetDistance.y / lpy, 0f);
            boxGo.transform.localRotation = Quaternion.identity;
            boxGo.transform.localScale = new Vector3(hitboxSize.x / lpx, hitboxSize.y / lpy, 1f);
            var sr = boxGo.AddComponent<SpriteRenderer>();
            sr.sprite = HitboxDebug.GetWhiteSprite();
            sr.color = new Color(1f, 0f, 0f, 0.35f);
            sr.sortingOrder = 100;
            sr.enabled = HitboxDebug.ShowDebugVisuals;
            Object.Destroy(boxGo, duration);

            // PD 지시 2026-05-13 — DamageFrameDelay·반복 피해 영역 정합 (Player 영역 매 hit 시 영역 영역 영역)
            inventory.StartCoroutine(MeleeFixedHitDamageCoroutine(inventory, data, damage));
        }

        static System.Collections.IEnumerator MeleeFixedHitDamageCoroutine(PlayerSkillInventory inventory, ActiveSkillData data, int damage)
        {
            for (int i = 0; i < data.DamageFrameDelay; i++) yield return null;
            DoOverlapBoxFromPlayer(inventory, data, damage);
            if (data.EnableRepeatDamage)
            {
                int remaining = Mathf.Max(0, data.MaxHitCount - 1);
                int interval = Mathf.Max(1, data.RepeatFrameInterval);
                for (int hit = 0; hit < remaining; hit++)
                {
                    for (int i = 0; i < interval; i++) yield return null;
                    if (inventory == null) yield break;
                    DoOverlapBoxFromPlayer(inventory, data, damage);
                }
            }
        }

        static void DoOverlapBoxFromPlayer(PlayerSkillInventory inventory, ActiveSkillData data, int damage)
        {
            if (inventory == null) return;
            // PD 지시 2026-05-13 — 박스(판정) = facing 좌/우 sign 만 · FxRotation 미적용
            Vector2 facing = Vector2.right;
            var pc = inventory.GetComponent<PlayerController>();
            if (pc != null) facing = pc.Facing;
            float signX = facing.x < 0f ? -1f : 1f;
            Vector2 hitboxPos = (Vector2)inventory.transform.position
                              + new Vector2(signX * data.OffsetDistance.x, data.OffsetDistance.y);
            var cf = new ContactFilter2D();
            cf.useTriggers = false;
            var results = new Collider2D[32];
            int n = Physics2D.OverlapBox(hitboxPos, data.HitboxSize, 0f, cf, results);
            for (int i = 0; i < n; i++)
            {
                var c = results[i];
                if (c == null) continue;
                var e = c.GetComponent<EnemyController>();
                if (e == null) continue;
                var h = c.GetComponent<Health>();
                if (h == null || !h.IsAlive) continue;
                h.DecrementBypassInvulnWithHit(damage);
                if (!h.IsAlive) Schedule<EnemyDeath>().enemy = e;
            }
        }

        static void AutoDestroyFx(GameObject fxGo)
        {
            if (fxGo == null) return;
            Object.Destroy(fxGo, GetFxLifetime(fxGo) + 0.2f);
        }

        static float GetFxLifetime(GameObject fxGo)
        {
            if (fxGo == null) return 1f;
            var psList = fxGo.GetComponentsInChildren<ParticleSystem>(true);
            float max = 0f;
            foreach (var ps in psList)
            {
                var main = ps.main;
                float t = main.duration + main.startLifetime.constantMax;
                if (t > max) max = t;
            }
            return Mathf.Max(max, 1f);
        }
    }
}