Lavaland chasms (#19154)

Content.Shared/Chasm/ChasmSystem.cs

@@ -0,0 +1,78 @@
+using Content.Shared.ActionBlocker;
+using Content.Shared.Movement.Events;
+using Content.Shared.StepTrigger.Systems;
+using Robust.Shared.Network;
+using Robust.Shared.Physics.Components;
+using Robust.Shared.Timing;
+
+namespace Content.Shared.Chasm;
+
+/// <summary>
+///     Handles making entities fall into chasms when stepped on.
+/// </summary>
+public sealed class ChasmSystem : EntitySystem
+{
+    [Dependency] private readonly IGameTiming _timing = default!;
+    [Dependency] private readonly ActionBlockerSystem _blocker = default!;
+    [Dependency] private readonly INetManager _net = default!;
+    [Dependency] private readonly SharedAudioSystem _audio = default!;
+
+    public override void Initialize()
+    {
+        base.Initialize();
+
+        SubscribeLocalEvent<ChasmComponent, StepTriggeredEvent>(OnStepTriggered);
+        SubscribeLocalEvent<ChasmComponent, StepTriggerAttemptEvent>(OnStepTriggerAttempt);
+        SubscribeLocalEvent<ChasmFallingComponent, EntityUnpausedEvent>(OnUnpaused);
+        SubscribeLocalEvent<ChasmFallingComponent, UpdateCanMoveEvent>(OnUpdateCanMove);
+    }
+
+    public override void Update(float frameTime)
+    {
+        base.Update(frameTime);
+
+        // don't predict queuedels on client
+        if (_net.IsClient)
+            return;
+
+        var query = EntityQueryEnumerator<ChasmFallingComponent>();
+        while (query.MoveNext(out var uid, out var chasm))
+        {
+            if (_timing.CurTime < chasm.NextDeletionTime)
+                continue;
+
+            QueueDel(uid);
+        }
+    }
+
+    private void OnStepTriggered(EntityUid uid, ChasmComponent component, ref StepTriggeredEvent args)
+    {
+        // already doomed
+        if (HasComp<ChasmFallingComponent>(args.Tripper))
+            return;
+
+        var falling = AddComp<ChasmFallingComponent>(args.Tripper);
+
+        falling.NextDeletionTime = _timing.CurTime + falling.DeletionTime;
+        _blocker.UpdateCanMove(args.Tripper);
+        _audio.PlayPredicted(component.FallingSound, uid, args.Tripper);
+    }
+
+    private void OnStepTriggerAttempt(EntityUid uid, ChasmComponent component, ref StepTriggerAttemptEvent args)
+    {
+        if (TryComp<PhysicsComponent>(args.Tripper, out var physics) && physics.BodyStatus == BodyStatus.InAir)
+            return;
+
+        args.Continue = true;
+    }
+
+    private void OnUnpaused(EntityUid uid, ChasmFallingComponent component, ref EntityUnpausedEvent args)
+    {
+        component.NextDeletionTime += args.PausedTime;
+    }
+
+    private void OnUpdateCanMove(EntityUid uid, ChasmFallingComponent component, UpdateCanMoveEvent args)
+    {
+        args.Cancel();
+    }
+}