Trigger On Hitscan (#40964)

* init

* doc

* merge systems

* review

Content.Shared/Trigger/Components/Triggers/TriggerOnHitscanFiredComponent.cs

@@ -0,0 +1,11 @@
+using Robust.Shared.GameStates;
+
+namespace Content.Shared.Trigger.Components.Triggers;
+
+/// <summary>
+/// Component put on the hitscan entity.
+/// Triggers when a hitscan raycast is fired.
+/// The user is the player shooting it.
+/// </summary>
+[RegisterComponent, NetworkedComponent, AutoGenerateComponentState]
+public sealed partial class TriggerOnHitscanFiredComponent : BaseTriggerOnXComponent;

Content.Shared/Trigger/Components/Triggers/TriggerOnHitscanHitComponent.cs

@@ -0,0 +1,11 @@
+using Robust.Shared.GameStates;
+
+namespace Content.Shared.Trigger.Components.Triggers;
+
+/// <summary>
+/// Component put on the hitscan entity.
+/// Triggers when a hitscan raycast is fired, but only if an entity got hit.
+/// The user is the entity that got hit.
+/// </summary>
+[RegisterComponent, NetworkedComponent, AutoGenerateComponentState]
+public sealed partial class TriggerOnHitscanHitComponent : BaseTriggerOnXComponent;

Content.Shared/Trigger/Systems/TriggerOnHitscanSystem.cs

@@ -0,0 +1,30 @@
+using Content.Shared.Trigger.Components.Triggers;
+using Content.Shared.Weapons.Hitscan.Events;
+
+namespace Content.Shared.Trigger.Systems;
+
+public sealed class TriggerOnHitscanSystem : EntitySystem
+{
+    [Dependency] private readonly TriggerSystem _trigger = default!;
+
+    public override void Initialize()
+    {
+        base.Initialize();
+
+        SubscribeLocalEvent<TriggerOnHitscanHitComponent, HitscanRaycastFiredEvent>(OnHit);
+        SubscribeLocalEvent<TriggerOnHitscanFiredComponent, HitscanRaycastFiredEvent>(OnFired);
+    }
+
+    private void OnHit(Entity<TriggerOnHitscanHitComponent> ent, ref HitscanRaycastFiredEvent args)
+    {
+        if (args.Data.HitEntity == null)
+            return;
+
+        _trigger.Trigger(ent.Owner, args.Data.HitEntity, ent.Comp.KeyOut);
+    }
+
+    private void OnFired(Entity<TriggerOnHitscanFiredComponent> ent, ref HitscanRaycastFiredEvent args)
+    {
+        _trigger.Trigger(ent.Owner, args.Data.Shooter, ent.Comp.KeyOut);
+    }
+}