Predict general interactions. (#6856)

Content.Shared/Timing/UseDelaySystem.cs

@@ -0,0 +1,138 @@
+using System.Threading;
+using Content.Shared.Cooldown;
+using Robust.Shared.GameStates;
+using Robust.Shared.Timing;
+using Robust.Shared.Utility;
+
+namespace Content.Shared.Timing;
+
+public sealed class UseDelaySystem : EntitySystem
+{
+    [Dependency] private readonly IGameTiming _gameTiming = default!;
+
+    private HashSet<UseDelayComponent> _activeDelays = new();
+
+    public override void Initialize()
+    {
+        base.Initialize();
+
+        SubscribeLocalEvent<UseDelayComponent, ComponentGetState>(OnGetState);
+        SubscribeLocalEvent<UseDelayComponent, ComponentHandleState>(OnHandleState);
+
+        SubscribeLocalEvent<UseDelayComponent, EntityPausedEvent>(OnPaused);
+    }
+
+    private void OnPaused(EntityUid uid, UseDelayComponent component, EntityPausedEvent args)
+    {
+        if (args.Paused)
+        {
+            // This entity just got paused, but wasn't before
+            if (component.DelayEndTime != null)
+                component.RemainingDelay = _gameTiming.CurTime - component.DelayEndTime;
+
+            _activeDelays.Remove(component);
+        }
+        else if (component.RemainingDelay == null)
+        {
+            // Got unpaused, but had no active delay
+            return;
+        }
+
+        // We got unpaused, resume the delay/cooldown. Currently this takes for granted that ItemCooldownComponent
+        // handles the pausing on its own. I'm not even gonna check, because I CBF fixing it if it doesn't.
+        component.DelayEndTime = _gameTiming.CurTime + component.RemainingDelay;
+        Dirty(component);
+        _activeDelays.Add(component);
+    }
+
+    private void OnHandleState(EntityUid uid, UseDelayComponent component, ref ComponentHandleState args)
+    {
+        if (args.Current is not UseDelayComponentState state)
+            return;
+
+        component.LastUseTime = state.LastUseTime;
+        component.Delay = state.Delay;
+        component.DelayEndTime = state.DelayEndTime;
+
+        if (component.DelayEndTime == null)
+            _activeDelays.Remove(component);
+        else
+            _activeDelays.Add(component);
+    }
+
+    private void OnGetState(EntityUid uid, UseDelayComponent component, ref ComponentGetState args)
+    {
+        args.State = new UseDelayComponentState(component.LastUseTime, component.Delay, component.DelayEndTime);
+    }
+
+    public override void Update(float frameTime)
+    {
+        base.Update(frameTime);
+
+        var toRemove = new RemQueue<UseDelayComponent>();
+        var curTime = _gameTiming.CurTime;
+        var mQuery = EntityManager.GetEntityQuery<MetaDataComponent>();
+
+        foreach (var delay in _activeDelays)
+        {
+            if (curTime > delay.DelayEndTime
+                || !mQuery.TryGetComponent(delay.Owner, out var meta)
+                || meta.Deleted
+                || delay.CancellationTokenSource?.Token.IsCancellationRequested == true)
+            {
+                toRemove.Add(delay);
+            }
+        }
+
+        foreach (var delay in toRemove)
+        {
+            delay.CancellationTokenSource = null;
+            delay.DelayEndTime = null;
+            _activeDelays.Remove(delay);
+        }
+    }
+
+    public void BeginDelay(EntityUid uid, UseDelayComponent? component = null)
+    {
+        if (!Resolve(uid, ref component, false))
+            return;
+
+        if (component.ActiveDelay || Deleted(uid)) return;
+
+        component.CancellationTokenSource = new CancellationTokenSource();
+
+        DebugTools.Assert(!_activeDelays.Contains(component));
+        _activeDelays.Add(component);
+
+        var currentTime = _gameTiming.CurTime;
+        component.LastUseTime = currentTime;
+        component.DelayEndTime = currentTime + component.Delay;
+        Dirty(component);
+
+        // TODO just merge these components?
+        var cooldown = EnsureComp<ItemCooldownComponent>(component.Owner);
+        cooldown.CooldownStart = currentTime;
+        cooldown.CooldownEnd = component.DelayEndTime;
+    }
+
+    public void Cancel(UseDelayComponent component)
+    {
+        component.CancellationTokenSource?.Cancel();
+        component.CancellationTokenSource = null;
+        component.DelayEndTime = null;
+        _activeDelays.Remove(component);
+        Dirty(component);
+
+        if (TryComp<ItemCooldownComponent>(component.Owner, out var cooldown))
+        {
+            cooldown.CooldownEnd = _gameTiming.CurTime;
+        }
+    }
+
+    public void Restart(UseDelayComponent component)
+    {
+        component.CancellationTokenSource?.Cancel();
+        component.CancellationTokenSource = null;
+        BeginDelay(component.Owner, component);
+    }
+}