using System;
using UnityEngine;
using Unity.Netcode;
using Colosseum.Stats;
using Colosseum.Combat;

namespace Colosseum.Enemy
{
    /// <summary>
    /// 적 캐릭터 기본 클래스.
    /// 네트워크 동기화, 스탯 관리, 대미지 처리를 담당합니다.
    /// </summary>
    public class EnemyBase : NetworkBehaviour, IDamageable
    {
        [Header("References")]
        [Tooltip("CharacterStats 컴포넌트 (없으면 자동 검색)")]
        [SerializeField] protected CharacterStats characterStats;
        [Tooltip("Animator 컴포넌트")]
        [SerializeField] protected Animator animator;
        [Tooltip("NavMeshAgent 또는 이동 컴포넌트")]
        [SerializeField] protected UnityEngine.AI.NavMeshAgent navMeshAgent;

        [Header("Data")]
        [SerializeField] protected EnemyData enemyData;

        // 네트워크 동기화 변수
        protected NetworkVariable<float> currentHealth = new NetworkVariable<float>(100f);
        protected NetworkVariable<float> currentMana = new NetworkVariable<float>(50f);
        protected NetworkVariable<bool> isDead = new NetworkVariable<bool>(false);

        // 이벤트
        public event Action<float, float> OnHealthChanged; // currentHealth, maxHealth
        public event Action<float> OnDamageTaken; // damage
        public event Action OnDeath;

        // Properties
        public float CurrentHealth => currentHealth.Value;
        public float MaxHealth => characterStats != null ? characterStats.MaxHealth : 100f;
        public float CurrentMana => currentMana.Value;
        public float MaxMana => characterStats != null ? characterStats.MaxMana : 50f;
        public bool IsDead => isDead.Value;
        public CharacterStats Stats => characterStats;
        public EnemyData Data => enemyData;
        public Animator Animator => animator;

        public override void OnNetworkSpawn()
        {
            // 컴포넌트 참조 확인
            if (characterStats == null)
                characterStats = GetComponent<CharacterStats>();
            if (animator == null)
                animator = GetComponentInChildren<Animator>();
            if (navMeshAgent == null)
                navMeshAgent = GetComponent<UnityEngine.AI.NavMeshAgent>();

            // 서버에서 초기화
            if (IsServer)
            {
                InitializeStats();
            }

            // 클라이언트에서 체력 변화 감지
            currentHealth.OnValueChanged += OnHealthChangedInternal;
        }

        public override void OnNetworkDespawn()
        {
            currentHealth.OnValueChanged -= OnHealthChangedInternal;
        }

        /// <summary>
        /// 스탯 초기화 (서버에서만 실행)
        /// </summary>
        protected virtual void InitializeStats()
        {
            if (enemyData != null && characterStats != null)
            {
                enemyData.ApplyBaseStats(characterStats);
            }

            // NavMeshAgent 속도 설정
            if (navMeshAgent != null && enemyData != null)
            {
                navMeshAgent.speed = enemyData.MoveSpeed;
                navMeshAgent.angularSpeed = enemyData.RotationSpeed;
            }

            currentHealth.Value = MaxHealth;
            currentMana.Value = MaxMana;
            isDead.Value = false;
        }











        /// <summary>
        /// 대미지 적용 (서버에서 실행)
        /// </summary>
        public virtual float TakeDamage(float damage, object source = null)
        {
            if (!IsServer || isDead.Value)
                return 0f;

            float actualDamage = Mathf.Min(damage, currentHealth.Value);
            currentHealth.Value = Mathf.Max(0f, currentHealth.Value - actualDamage);

            OnDamageTaken?.Invoke(actualDamage);

            // 대미지 피드백 (애니메이션, 이펙트 등)
            OnTakeDamageFeedback(actualDamage, source);

            if (currentHealth.Value <= 0f)
            {
                HandleDeath();
            }

            return actualDamage;
        }

        /// <summary>
        /// 대미지 피드백 (애니메이션, 이펙트)
        /// </summary>
        protected virtual void OnTakeDamageFeedback(float damage, object source)
        {
            if (animator != null)
            {
                animator.SetTrigger("Hit");
            }
        }

        /// <summary>
        /// 체력 회복 (서버에서 실행)
        /// </summary>
        public virtual float Heal(float amount)
        {
            if (!IsServer || isDead.Value)
                return 0f;

            float oldHealth = currentHealth.Value;
            currentHealth.Value = Mathf.Min(MaxHealth, currentHealth.Value + amount);
            float actualHeal = currentHealth.Value - oldHealth;

            return actualHeal;
        }

        /// <summary>
        /// 사망 처리 (서버에서 실행)
        /// </summary>
        protected virtual void HandleDeath()
        {
            isDead.Value = true;

            if (animator != null)
            {
                animator.SetTrigger("Die");
            }

            if (navMeshAgent != null)
            {
                navMeshAgent.isStopped = true;
            }

            OnDeath?.Invoke();

            Debug.Log($"[Enemy] {name} died!");
        }

        /// <summary>
        /// 리스폰
        /// </summary>
        public virtual void Respawn()
        {
            if (!IsServer) return;

            isDead.Value = false;
            InitializeStats();

            if (navMeshAgent != null)
            {
                navMeshAgent.isStopped = false;
            }

            if (animator != null)
            {
                animator.Rebind();
            }
        }

        // 체력 변화 이벤트 전파
        private void OnHealthChangedInternal(float oldValue, float newValue)
        {
            OnHealthChanged?.Invoke(newValue, MaxHealth);
        }
    }
}