TheKingsRace/Assets/Scripts/UI/Lobby/LobbyUI.cs

using System;
using MLAPI;
using MLAPI.Connection;
using MLAPI.Messaging;
using MLAPI.NetworkVariable.Collections;
using TMPro;
using UnityEngine;
using UnityEngine.UI;

public class LobbyUI : NetworkBehaviour {

    [Header("References")]
    [SerializeField] private LobbyPlayerCard[] lobbyPlayerCards;
    [SerializeField] private Button startGameButton;
    [SerializeField] private TMP_Text lobbyStateText;

    private NetworkList<LobbyPlayerState> lobbyPlayers = new NetworkList<LobbyPlayerState>();

    public override void NetworkStart()
    {
        if (IsClient)
        {
            lobbyPlayers.OnListChanged += HandleLobbyPlayersStateChanged;
        }

        if (IsServer)
        {
            startGameButton.gameObject.SetActive(true);

            NetworkManager.Singleton.OnClientConnectedCallback += HandleClientConnected;
            NetworkManager.Singleton.OnClientDisconnectCallback += HandleClientDisconnect;

            foreach (NetworkClient client in NetworkManager.Singleton.ConnectedClientsList)
            {
                HandleClientConnected(client.ClientId);
            }
        }
    }

    private void OnDestroy()
    {
        lobbyPlayers.OnListChanged -= HandleLobbyPlayersStateChanged;

        if (NetworkManager.Singleton)
        {
            NetworkManager.Singleton.OnClientConnectedCallback -= HandleClientConnected;
            NetworkManager.Singleton.OnClientDisconnectCallback -= HandleClientDisconnect;
        }
    }

    private bool IsEveryoneReady()
    {
        // Make sure there is 3 players in the lobby
        if (lobbyPlayers.Count != 3)
        {
            lobbyStateText.text = "Need 3 Players To Begin!";
            return false;
        }

        foreach (var player in lobbyPlayers)
        {
            if (!player.IsReady)
            {
                lobbyStateText.text = "All Players Must Ready Up To Begin!";
                return false;
            }
        }

        return true;
    }

    private bool AreRolesFilled() {
        int runnerCount = 0;
        int kingCount = 0;
        foreach (var player in lobbyPlayers) {
            // Check how many of each player
            if (player.IsKing) {
                kingCount++;
            } else {
                runnerCount++;
            }
        }

        // Verify counts
        if (runnerCount != 2 || kingCount != 1) {
            return false;
        }

        return true;
    }

    private void HandleClientConnected(ulong clientId)
    {
        var playerData = ServerGameNetPortal.Instance.GetPlayerData(clientId);

        if (!playerData.HasValue) { return; }

        lobbyPlayers.Add(new LobbyPlayerState(
            clientId,
            playerData.Value.PlayerName,
            false,
            false
        ));
    }

    private void HandleClientDisconnect(ulong clientId)
    {
        for (int i = 0; i < lobbyPlayers.Count; i++)
        {
            if (lobbyPlayers[i].ClientId == clientId)
            {
                lobbyPlayers.RemoveAt(i);
                break;
            }
        }
    }

    [ServerRpc(RequireOwnership = false)]
    private void ToggleReadyServerRpc(ServerRpcParams serverRpcParams = default)
    {
        for (int i = 0; i < lobbyPlayers.Count; i++)
        {
            if (lobbyPlayers[i].ClientId == serverRpcParams.Receive.SenderClientId)
            {
                lobbyPlayers[i] = new LobbyPlayerState(
                    lobbyPlayers[i].ClientId,
                    lobbyPlayers[i].PlayerName,
                    !lobbyPlayers[i].IsReady,
                    lobbyPlayers[i].IsKing
                );
            }
        }
    }

    [ServerRpc(RequireOwnership = false)]
    private void SwapTeamsServerRpc(ServerRpcParams serverRpcParams = default) { 
        for (int i = 0; i < lobbyPlayers.Count; i++) {
            ulong senderClientID = serverRpcParams.Receive.SenderClientId;
            // Update the lobby state that controls that player's data
            if (lobbyPlayers[i].ClientId == senderClientID) {
                lobbyPlayers[i] = new LobbyPlayerState(
                    lobbyPlayers[i].ClientId,
                    lobbyPlayers[i].PlayerName,
                    lobbyPlayers[i].IsReady,
                    !lobbyPlayers[i].IsKing
                );

                // Update the server's player data as well
                if (ServerGameNetPortal.Instance.clientIdToGuid.TryGetValue(senderClientID, out string clientGuid)) {
                    ServerGameNetPortal.Instance.clientData[clientGuid] = new PlayerData(
                        ServerGameNetPortal.Instance.clientData[clientGuid].PlayerName,
                        ServerGameNetPortal.Instance.clientData[clientGuid].ClientId,
                        lobbyPlayers[i].IsKing
                    );
                }
            }
        }
    }

    [ServerRpc(RequireOwnership = false)]
    private void StartGameServerRpc(ServerRpcParams serverRpcParams = default)
    {
        if (serverRpcParams.Receive.SenderClientId != NetworkManager.Singleton.LocalClientId) { return; }

        if (!IsEveryoneReady() && !AreRolesFilled()) { return; }

        ServerGameNetPortal.Instance.StartGame();
    }

    public void OnLeaveClicked()
    {
        GameNetPortal.Instance.RequestDisconnect();
    }

    public void OnReadyClicked()
    {
        ToggleReadyServerRpc();
    }

    public void OnStartGameClicked()
    {
        StartGameServerRpc();
    }

    public void OnSwapTeamClicked() {
        SwapTeamsServerRpc();
    }

    private void HandleLobbyPlayersStateChanged(NetworkListEvent<LobbyPlayerState> lobbyState) { 
        for (int i = 0; i < lobbyPlayerCards.Length; i++)
        {
            if (lobbyPlayers.Count > i)
            {
                lobbyPlayerCards[i].UpdateDisplay(lobbyPlayers[i]);
            }
            else
            {
                lobbyPlayerCards[i].DisableDisplay();
            }
        }

        if(IsHost)
        {
            if (IsEveryoneReady() && AreRolesFilled()) {
                startGameButton.interactable = true;
            } else {
                startGameButton.interactable = false;
            }
        }

        UpdateLobbyStateText();
    }

    private void UpdateLobbyStateText() {

        if (lobbyPlayers.Count != 3) {
            lobbyStateText.text = "Need 3 Players to Begin!";
            return;
        }

        int runnerCount = 0;
        int kingCount = 0;
        foreach (var player in lobbyPlayers) {
            // Check how many of each player
            if (player.IsKing) {
                kingCount++;
            } else {
                runnerCount++;
            }
        }

        if (IsEveryoneReady()) {

            // Verify counts
            if (runnerCount != 2 || kingCount != 1) {
                lobbyStateText.text = "Need 2 Runners and 1 King!";
                return;
            }

            lobbyStateText.text = "All Players Ready!";
        }
        else {
            lobbyStateText.text = "All Players Need to Ready Up!";
        }
    }
}