station_obscurum_unity/Assets/Scripts/Steam/SteamLobbyWithPlayer.cs

using System;
using System.Collections.Generic;
using System.Threading.Tasks;
using Steamworks;
using Steamworks.Data;
using UnityEngine;
using UnityEngine.Events;
using UnityEngine.UI;

public class SteamLobbyWithPlayer : MonoBehaviour
{
    
    public static Lobby CurrentLobby;
    public static bool UserInLobby;
    public UnityEvent onLobbyCreated;
    public UnityEvent onLobbyJoined;
    public UnityEvent onLobbyLeave;


    public Dictionary<SteamId, GameObject> inLobby = new();
    public GameObject playerPrefab;
    private void Start()
    {
        DontDestroyOnLoad(this);

        SteamMatchmaking.OnLobbyCreated += OnLobbyCreatedCallBack;
        SteamMatchmaking.OnLobbyEntered += OnLobbyEntered;
        SteamMatchmaking.OnLobbyMemberJoined += OnLobbyMemberJoined;
        // SteamMatchmaking.OnChatMessage += OnChatMessage;
        SteamMatchmaking.OnLobbyMemberDisconnected += OnLobbyMemberDisconnected;
        SteamMatchmaking.OnLobbyMemberLeave += OnLobbyMemberDisconnected;
        SteamMatchmaking.OnLobbyGameCreated += OnLobbyGameCreated;
        SteamFriends.OnGameLobbyJoinRequested += OnGameLobbyJoinRequest;
        SteamMatchmaking.OnLobbyInvite += OnLobbyInvite;
        CreateLobbyAsync();
    }

    private void OnLobbyInvite(Friend friend, Lobby lobby)
    {
        Debug.Log($"{friend.Name} invited you to his lobby.");
    }
    
    private void OnLobbyGameCreated(Lobby lobby, uint ip, ushort port, SteamId id)
    {
    }
    private async void OnLobbyMemberJoined(Lobby lobby, Friend friend)
    {
        Debug.Log($"{friend.Name} joined the lobby");
        GameObject obj = Instantiate(playerPrefab, Vector3.zero, Quaternion.identity);
        inLobby.Add(friend.Id, obj);
    }
    private void OnLobbyMemberDisconnected(Lobby lobby, Friend friend)
    {
        Debug.Log($"{friend.Name} left the lobby");
        Debug.Log($"New lobby owner is {CurrentLobby.Owner}");
        if (inLobby.ContainsKey(friend.Id))
        {
            Destroy(inLobby[friend.Id]);
            inLobby.Remove(friend.Id);
        }
    }
    private async void OnGameLobbyJoinRequest(Lobby joinedLobby, SteamId id)
    {
        var joinedLobbySuccess = await joinedLobby.Join();
        if (joinedLobbySuccess != RoomEnter.Success)
            Debug.Log("failed to join lobby : " + joinedLobbySuccess);
        else
            CurrentLobby = joinedLobby;
    }
    private void OnLobbyCreatedCallBack(Result result, Lobby lobby)
    {
        if (result != Result.OK)
        {
            Debug.Log("lobby creation result not ok : " + result);
        }
        else
        {
            onLobbyCreated.Invoke();
            Debug.Log("lobby creation result ok");
        }
    }
    private async void OnLobbyEntered(Lobby lobby)
    {
        Debug.Log("Client joined the lobby");
        UserInLobby = true;
        foreach (var user in inLobby.Values) Destroy(user);
        inLobby.Clear();

        GameObject player = Instantiate(playerPrefab);
        if(player == null)
            Debug.Log("Player is null");
        player.SetActive(true);
        inLobby.Add(SteamClient.SteamId, player);

        foreach (var friend in CurrentLobby.Members)
            if (friend.Id != SteamClient.SteamId)
            {
                GameObject other_player = Instantiate(playerPrefab, Vector3.zero, Quaternion.identity);

                inLobby.Add(friend.Id, other_player);
            }

        onLobbyJoined.Invoke();
    }
    public async void CreateLobbyAsync()
    {
        var result = await CreateLobby();
        if (!result)
        {
           Debug.Log("Failed to create lobby");
        }
        else
        {
            Debug.Log("Lobby created");
        }
        
    }
    public static async Task<bool> CreateLobby()
    {
        try
        {
            var createLobbyOutput = await SteamMatchmaking.CreateLobbyAsync();
            if (!createLobbyOutput.HasValue)
            {
                Debug.Log("Lobby created but not correctly instantiated.");
                return false;
            }

            CurrentLobby = createLobbyOutput.Value;

            CurrentLobby.SetPublic();
            //currentLobby.SetPrivate();
            CurrentLobby.SetJoinable(true);

            return true;
        }
        catch (Exception exception)
        {
            Debug.Log("Failed to create multiplayer lobby : " + exception);
            return false;
        }
    }
    public void LeaveLobby()
    {
        try
        {
            UserInLobby = false;
            CurrentLobby.Leave();
            onLobbyLeave.Invoke();
            foreach (var user in inLobby.Values) Destroy(user);
            inLobby.Clear();
        }
        catch
        {
            
        }
    }
    private void Update()
    {
        if(Input.GetKeyDown(KeyCode.Return)) {
            print("OWNER?:"+CurrentLobby.Owner);
        }
    }
}