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

namespace Northbound
{
    public class PlayerSpawnPositionSetter : NetworkBehaviour
    {
        public static PlayerSpawnPositionSetter Instance { get; private set; }

        [Header("Spawn Settings")]
        public List<Transform> spawnPoints = new List<Transform>();
        public bool useRandomSpawn = false;
        public bool findSpawnPointsAutomatically = true;

        private void Awake()
        {
            if (Instance != null && Instance != this)
            {
                Destroy(gameObject);
                return;
            }
            Instance = this;

            if (findSpawnPointsAutomatically)
            {
                FindSpawnPoints();
            }
        }

        private void FindSpawnPoints()
        {
            PlayerSpawnPoint[] points = FindObjectsByType<PlayerSpawnPoint>(FindObjectsSortMode.None);
            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>[SpawnPositionSetter] {spawnPoints.Count}개의 스폰 포인트를 찾았습니다.</color>");
        }

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

            int spawnIndex = GetSpawnIndexForClient(clientId);

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

        private int GetSpawnIndexForClient(ulong clientId)
        {
            if (useRandomSpawn)
            {
                return Random.Range(0, spawnPoints.Count);
            }

            int spawnIndex;
            if (IsServer)
            {
                spawnIndex = GetAssignedSpawnIndexServer(clientId);
            }
            else
            {
                spawnIndex = (int)(clientId % (ulong)spawnPoints.Count);
            }

            return spawnIndex;
        }

        private int GetAssignedSpawnIndexServer(ulong clientId)
        {
            List<ulong> connectedClientIds = new List<ulong>(NetworkManager.Singleton.ConnectedClientsIds);
            connectedClientIds.Sort();

            int index = connectedClientIds.IndexOf(clientId);
            if (index < 0) index = 0;

            return index % spawnPoints.Count;
        }

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

            int spawnIndex = GetSpawnIndexForClient(clientId);
            return spawnPoints[spawnIndex].rotation;
        }
    }
}