using System.Collections.Generic;
using System.Linq;
using Unity.Netcode;
using UnityEngine;

namespace Northbound
{
    /// <summary>
    /// 네트워크 연결 및 스폰 관리
    /// </summary>
    public class NetworkConnectionHandler : MonoBehaviour
    {
        [Header("Spawn Settings")]
        public List<Transform> spawnPoints = new List<Transform>();
        public bool useRandomSpawn = false;
        public bool findSpawnPointsAutomatically = true;
        
        private Dictionary<ulong, int> _clientSpawnIndices = new Dictionary<ulong, int>();
        private int _nextSpawnIndex = 0;

        // ⭐ Awake에서 스폰 포인트 먼저 찾고, 콜백 등록
        private void Awake()
        {
            // 1️⃣ 먼저 스폰 포인트 찾기
            if (findSpawnPointsAutomatically)
            {
                FindSpawnPoints();
            }

            // 2️⃣ 그 다음 콜백 등록
            if (NetworkManager.Singleton != null)
            {
                NetworkManager.Singleton.ConnectionApprovalCallback = ApprovalCheck;
                NetworkManager.Singleton.OnServerStarted += OnServerStarted;
                Debug.Log("<color=cyan>[Connection] ConnectionApprovalCallback 등록됨</color>");
            }
            else
            {
                Debug.LogError("[Connection] NetworkManager.Singleton이 null입니다!");
            }
        }

        private void FindSpawnPoints()
        {
            PlayerSpawnPoint[] points = FindObjectsByType<PlayerSpawnPoint>(FindObjectsSortMode.None);
            
            // spawnIndex로 정렬
            var sortedPoints = points.OrderBy(p => p.spawnIndex == -1 ? int.MaxValue : p.spawnIndex);
            
            spawnPoints.Clear();
            foreach (var point in sortedPoints)
            {
                if (point.isAvailable)
                {
                    spawnPoints.Add(point.transform);
                }
            }

            Debug.Log($"<color=cyan>[Connection] {spawnPoints.Count}개의 스폰 포인트를 찾았습니다.</color>");
        }

        private void OnServerStarted()
        {
            Debug.Log("<color=green>[Connection] 서버 시작됨</color>");
        }

        private void ApprovalCheck(
            NetworkManager.ConnectionApprovalRequest request,
            NetworkManager.ConnectionApprovalResponse response)
        {
            // 🔍 디버깅: 스폰 포인트 상태 확인
            if (spawnPoints.Count == 0)
            {
                Debug.LogError($"<color=red>[Connection] 스폰 포인트가 없습니다! 씬에 PlayerSpawnPoint가 있는지 확인하세요.</color>");
            }

            response.Approved = true;
            response.CreatePlayerObject = true;

            // 스폰 위치 설정
            response.Position = GetSpawnPosition(request.ClientNetworkId);
            response.Rotation = GetSpawnRotation(request.ClientNetworkId);

            Debug.Log($"<color=green>[Connection] 클라이언트 {request.ClientNetworkId} 승인됨. 스폰 위치: {response.Position}</color>");
        }

        private Vector3 GetSpawnPosition(ulong clientId)
        {
            if (spawnPoints.Count == 0)
            {
                Debug.LogWarning("[Connection] 스폰 포인트가 없습니다. 기본 위치 반환.");
                return Vector3.zero;
            }

            int spawnIndex;

            if (useRandomSpawn)
            {
                spawnIndex = Random.Range(0, spawnPoints.Count);
            }
            else
            {
                if (!_clientSpawnIndices.ContainsKey(clientId))
                {
                    _clientSpawnIndices[clientId] = _nextSpawnIndex;
                    _nextSpawnIndex = (_nextSpawnIndex + 1) % spawnPoints.Count;
                }
                spawnIndex = _clientSpawnIndices[clientId];
            }

            Debug.Log($"<color=yellow>[Connection] 클라이언트 {clientId}에게 스폰 인덱스 {spawnIndex} 할당</color>");
            return spawnPoints[spawnIndex].position;
        }

        private Quaternion GetSpawnRotation(ulong clientId)
        {
            if (spawnPoints.Count == 0)
                return Quaternion.identity;

            int spawnIndex = _clientSpawnIndices.ContainsKey(clientId) 
                ? _clientSpawnIndices[clientId] 
                : 0;

            return spawnPoints[spawnIndex].rotation;
        }

        private void OnDestroy()
        {
            if (NetworkManager.Singleton != null)
            {
                NetworkManager.Singleton.ConnectionApprovalCallback = null;
                NetworkManager.Singleton.OnServerStarted -= OnServerStarted;
            }
        }
    }
}