Refactor Game Modes (#5857)

Content.Server/GameTicking/Rules/DeathMatchRuleSystem.cs

@@ -0,0 +1,127 @@
+using Content.Server.Chat.Managers;
+using Content.Shared.CCVar;
+using Content.Shared.Damage;
+using Content.Shared.MobState.Components;
+using Robust.Server.Player;
+using Robust.Shared.Configuration;
+using Robust.Shared.Enums;
+using Robust.Shared.IoC;
+using Robust.Shared.Localization;
+
+namespace Content.Server.GameTicking.Rules;
+
+/// <summary>
+///     Simple GameRule that will do a free-for-all death match.
+///     Kill everybody else to win.
+/// </summary>
+public sealed class DeathMatchRuleSystem : GameRuleSystem
+{
+    public override string Prototype => "DeathMatch";
+
+    [Dependency] private readonly IPlayerManager _playerManager = default!;
+    [Dependency] private readonly IChatManager _chatManager = default!;
+    [Dependency] private readonly IConfigurationManager _cfg = default!;
+
+    private const float RestartDelay = 10f;
+    private const float DeadCheckDelay = 5f;
+
+    private float? _deadCheckTimer = null;
+    private float? _restartTimer = null;
+
+    public override void Initialize()
+    {
+        base.Initialize();
+
+        SubscribeLocalEvent<DamageChangedEvent>(OnHealthChanged);
+    }
+
+    public override void Added()
+    {
+        _chatManager.DispatchServerAnnouncement(Loc.GetString("rule-death-match-added-announcement"));
+
+        _playerManager.PlayerStatusChanged += OnPlayerStatusChanged;
+    }
+
+    public override void Removed()
+    {
+        _deadCheckTimer = null;
+        _restartTimer = null;
+
+        _playerManager.PlayerStatusChanged -= OnPlayerStatusChanged;
+    }
+
+    private void OnHealthChanged(DamageChangedEvent _)
+    {
+        RunDelayedCheck();
+    }
+
+    private void OnPlayerStatusChanged(object? _, SessionStatusEventArgs e)
+    {
+        if (e.NewStatus == SessionStatus.Disconnected)
+        {
+            RunDelayedCheck();
+        }
+    }
+
+    private void RunDelayedCheck()
+    {
+        if (!Enabled || _deadCheckTimer != null)
+            return;
+
+        _deadCheckTimer = DeadCheckDelay;
+    }
+
+    public override void Update(float frameTime)
+    {
+        if (!Enabled)
+            return;
+
+        // If the restart timer is active, that means the round is ending soon, no need to check for winners.
+        // TODO: We probably want a sane, centralized round end thingie in GameTicker, RoundEndSystem is no good...
+        if (_restartTimer != null)
+        {
+            _restartTimer -= frameTime;
+
+            if (_restartTimer > 0f)
+                return;
+
+            GameTicker.EndRound();
+            GameTicker.RestartRound();
+            return;
+        }
+
+        if (!_cfg.GetCVar(CCVars.GameLobbyEnableWin) || _deadCheckTimer == null)
+            return;
+
+        _deadCheckTimer -= frameTime;
+
+        if (_deadCheckTimer > 0)
+            return;
+
+        _deadCheckTimer = null;
+
+        IPlayerSession? winner = null;
+        foreach (var playerSession in _playerManager.ServerSessions)
+        {
+            if (playerSession.AttachedEntity is not {Valid: true} playerEntity
+                || !TryComp(playerEntity, out MobStateComponent? state))
+                continue;
+
+            if (!state.IsAlive())
+                continue;
+
+            // Found a second person alive, nothing decided yet!
+            if (winner != null)
+                return;
+
+            winner = playerSession;
+        }
+
+        _chatManager.DispatchServerAnnouncement(winner == null
+            ? Loc.GetString("rule-death-match-check-winner-stalemate")
+            : Loc.GetString("rule-death-match-check-winner",("winner", winner)));
+
+        _chatManager.DispatchServerAnnouncement(Loc.GetString("rule-restarting-in-seconds", ("seconds", RestartDelay)));
+        _restartTimer = RestartDelay;
+    }
+}