using UnityEngine;

namespace Colosseum.Skills
{
    /// <summary>
    /// 스킬 투사체. 충돌 시 연결된 효과를 적용합니다.
    /// </summary>
    [RequireComponent(typeof(Rigidbody))]
    public class SkillProjectile : MonoBehaviour
    {
        [Header("이동 설정")]
        [Min(0f)] [SerializeField] private float speed = 15f;
        [Min(0f)] [SerializeField] private float lifetime = 5f;

        [Header("관통 설정")]
        [SerializeField] private bool penetrate = false;
        [SerializeField] private int maxPenetration = 1;

        [Header("충돌 이펙트")]
        [SerializeField] private GameObject hitEffect;
        [SerializeField] private float hitEffectDuration = 2f;

        private GameObject caster;
        private SkillEffect sourceEffect;
        private int penetrationCount;
        private Rigidbody rb;
        private bool initialized;

        /// <summary>
        /// 투사체 초기화
        /// </summary>
        public void Initialize(GameObject caster, SkillEffect sourceEffect)
        {
            this.caster = caster;
            this.sourceEffect = sourceEffect;
            initialized = true;

            rb = GetComponent<Rigidbody>();
            if (rb != null)
            {
                rb.useGravity = false;
                rb.collisionDetectionMode = CollisionDetectionMode.ContinuousDynamic;
            }
        }

        private void Start()
        {
            Destroy(gameObject, lifetime);
        }

        private void FixedUpdate()
        {
            if (!initialized || rb == null) return;
            rb.linearVelocity = transform.forward * speed;
        }

        private void OnTriggerEnter(Collider other)
        {
            if (!initialized || sourceEffect == null) return;
            if (other.gameObject == caster) return;

            // 유효한 타겟인지 확인
            if (!sourceEffect.IsValidTarget(caster, other.gameObject))
                return;

            // 충돌 이펙트
            if (hitEffect != null)
            {
                var effect = Instantiate(hitEffect, transform.position, transform.rotation);
                Destroy(effect, hitEffectDuration);
            }

            // 효과 적용
            sourceEffect.ExecuteOnHit(caster, other.gameObject);

            penetrationCount++;

            if (!penetrate || penetrationCount >= maxPenetration)
            {
                Destroy(gameObject);
            }
        }

        public void SetDirection(Vector3 direction)
        {
            transform.rotation = Quaternion.LookRotation(direction.normalized);
        }
    }
}