fgm24/Assets/Scripts/Multiplayer/SteamManager.cs

using Assets.Scripts.Multiplayer;
using Netcode.Transports.Facepunch;
using Steamworks;
using Steamworks.Data;
using System;
using System.Collections;
using System.Collections.Generic;
using TMPro;
using Unity.Netcode;
using Unity.Netcode.Transports.UTP;
using UnityEngine;
using UnityEngine.SceneManagement;
using UnityEngine.UI;

public class SteamManager : ZNetworkData
{
    [SerializeField] private Button HostBtn;
    [SerializeField] private Button JoinBtn;

    [SerializeField] private TMP_InputField LobbyIdInputField;
    [SerializeField] private TextMeshProUGUI LobbyID;
    [SerializeField] private GameObject MainMenu;
    [SerializeField] private GameObject InLobbyMenu;

    private void Start()
    {
        if (NetworkManager.Singleton == null) return;

        bool isLocal = NetworkManager.Singleton.NetworkConfig.NetworkTransport is UnityTransport;
        if (isLocal) Destroy(gameObject);

        SteamMatchmaking.OnLobbyCreated += LobbyCreated;
        SteamMatchmaking.OnLobbyEntered += LobbyEntered;
        SteamFriends.OnGameLobbyJoinRequested += GameLobbyJoinRequested;

        HostBtn.onClick.AddListener(HostLobby);
        JoinBtn.onClick.AddListener(JoinLobbyWithID);

        DisableLoadingText();
    }

    private void LobbyCreated(Result result, Lobby lobby)
    {
        if (result == Result.OK)
        {
            lobby.SetPublic();
            lobby.SetJoinable(true);
            NetworkManager.Singleton.StartHost();
        }
    }

    private void LobbyEntered(Lobby lobby)
    {
        SteamLobbySaver.Instance.currentLobby = lobby;
        LobbyID.text = lobby.Id.ToString();
        MainMenu.SetActive(false);
        InLobbyMenu.SetActive(true);

        NetworkManager.Singleton.gameObject.GetComponent<FacepunchTransport>().targetSteamId = lobby.Owner.Id;
        NetworkManager.Singleton.StartClient();

        Debug.Log("Entered lobby");
    }

    private async void GameLobbyJoinRequested(Lobby lobby, SteamId id)
    {
        await lobby.Join();
    }

    private void OnDisable()
    {
        SteamMatchmaking.OnLobbyCreated -= LobbyCreated;
        SteamMatchmaking.OnLobbyEntered -= LobbyEntered;
        SteamFriends.OnGameLobbyJoinRequested -= GameLobbyJoinRequested;
    }

    public async void HostLobby()
    {
        IsServer = true;

        await SteamMatchmaking.CreateLobbyAsync(4);
    }

    public void LeaveLobby()
    {
        SteamLobbySaver.Instance.currentLobby?.Leave();
        SteamLobbySaver.Instance.currentLobby = null;
        NetworkManager.Singleton.Shutdown();
        UpdateUI();
    }

    public void StartGameServer()
    {
        if (!NetworkManager.Singleton.IsHost) return;

        // Gets next scene name
        int nextSceneIndex = SceneManager.GetActiveScene().buildIndex + 1;
        string nextSceneName = SceneUtility.GetScenePathByBuildIndex(nextSceneIndex);

        NetworkManager.Singleton.SceneManager.LoadScene(nextSceneName, UnityEngine.SceneManagement.LoadSceneMode.Single);
    }

    private void UpdateUI()
    {
        if (SteamLobbySaver.Instance.currentLobby == null)
        {
            // Show main menu
            MainMenu.SetActive(true);
            InLobbyMenu.SetActive(false);
        }
        else
        {
            // Show In lobby ui
            MainMenu.SetActive(false);
            InLobbyMenu.SetActive(true);
        }
    }

    public async void JoinLobbyWithID()
    {
        ulong id;
        if (!ulong.TryParse(LobbyIdInputField.text, out id))
        {
            return; // If id inputted is not ulong, then return
        }

        Lobby[] lobbies = await SteamMatchmaking.LobbyList.WithSlotsAvailable(1).RequestAsync();

        foreach (Lobby lobby in lobbies)
        {
            if (lobby.Id == id) // If found target lobby, then join
            {
                await lobby.Join();
                return;
            }
        }
    }
}