ClientConnectionHandler

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

public class ClientConnectionHandler : NetworkBehaviour
{
    public NetworkPrefab[] alternatePlayerPrefabs;

    public void SetClientPlayerPrefab(int index)
    {
        if (index >= alternatePlayerPrefabs.Length)
        {
            Debug.LogError($"Trying to assign player prefab index of {index} when there are only {alternatePlayerPrefabs.Length} entries!");
            return;
        }

        if (NetworkManager.Singleton.IsListening || IsSpawned)
        {
            Debug.LogError("This needs to be set before connecting!");
            return;
        }

        NetworkManager.Singleton.NetworkConfig.ConnectionData = System.BitConverter.GetBytes(index);
    }

    public override void OnNetworkSpawn()
    {
        if (IsServer)
        {
            NetworkManager.Singleton.ConnectionApprovalCallback += ConnectionApprovalCallback;
        }
    }

    private void ConnectionApprovalCallback(byte[] connectionData, ulong clientId, NetworkManager.ConnectionApprovedDelegate callback)
    {
        int playerPrefabIndex = System.BitConverter.ToInt32(connectionData, 0);

        if (playerPrefabIndex >= alternatePlayerPrefabs.Length)
        {
            Debug.LogError($"Client provided player prefab index of {playerPrefabIndex} when there are only {alternatePlayerPrefabs.Length} entries!");
            callback(false, 0, null, null, null);
            return;
        }

        NetworkPrefab playerPrefab = alternatePlayerPrefabs[playerPrefabIndex];

        // Create additional player-specific data
        PlayerData playerData = new PlayerData();

        // Set additional player-specific properties
        playerData.playerName = "Player " + clientId;
        playerData.playerScore = 0;

        // Create additional scene manager data
        SceneManagerData sceneManagerData = new SceneManagerData();

        // Set additional scene manager properties
        sceneManagerData.levelName = "Level 1";
        sceneManagerData.maxPlayers = 4;

        // Complete the connection approval response by providing the player prefab, player data, and scene manager data
        callback(true, playerPrefab.PrefabHash, playerData, sceneManagerData, playerPrefab.Prefab);
    }
}

[System.Serializable]
public class PlayerData
{
    public string playerName;
    public int playerScore;
    // Add more properties as needed
}

[System.Serializable]
public class SceneManagerData
{
    public string levelName;
    public int maxPlayers;
    // Add more properties as needed
}