From e16bca5b181c4d72070513f675cd0d320f7b04ff Mon Sep 17 00:00:00 2001
From: slarticodefast <161409025+slarticodefast@users.noreply.github.com>
Date: Mon, 18 Aug 2025 01:47:26 +0200
Subject: [PATCH] Hand pickup and drop triggers (#39663)

---
 .../TriggerOnDidEquipHandComponent.cs         | 10 +++
 .../TriggerOnDidUnequipHandComponent.cs       | 10 +++
 .../Triggers/TriggerOnDroppedComponent.cs     | 10 +++
 .../TriggerOnGotEquippedHandComponent.cs      | 10 +++
 .../TriggerOnGotUnequippedHandComponent.cs    | 10 +++
 .../Trigger/Systems/HandTriggerSystem.cs      | 64 +++++++++++++++++++
 6 files changed, 114 insertions(+)
 create mode 100644 Content.Shared/Trigger/Components/Triggers/TriggerOnDidEquipHandComponent.cs
 create mode 100644 Content.Shared/Trigger/Components/Triggers/TriggerOnDidUnequipHandComponent.cs
 create mode 100644 Content.Shared/Trigger/Components/Triggers/TriggerOnDroppedComponent.cs
 create mode 100644 Content.Shared/Trigger/Components/Triggers/TriggerOnGotEquippedHandComponent.cs
 create mode 100644 Content.Shared/Trigger/Components/Triggers/TriggerOnGotUnequippedHandComponent.cs
 create mode 100644 Content.Shared/Trigger/Systems/HandTriggerSystem.cs

diff --git a/Content.Shared/Trigger/Components/Triggers/TriggerOnDidEquipHandComponent.cs b/Content.Shared/Trigger/Components/Triggers/TriggerOnDidEquipHandComponent.cs
new file mode 100644
index 0000000000..d598db6d93
--- /dev/null
+++ b/Content.Shared/Trigger/Components/Triggers/TriggerOnDidEquipHandComponent.cs
@@ -0,0 +1,10 @@
+using Robust.Shared.GameStates;
+
+namespace Content.Shared.Trigger.Components.Triggers;
+
+/// <summary>
+/// Triggers an entity when it is equips an item into one of its hand slots.
+/// The user is the entity that was equipped.
+/// </summary>
+[RegisterComponent, NetworkedComponent, AutoGenerateComponentState]
+public sealed partial class TriggerOnDidEquipHandComponent : BaseTriggerOnXComponent;
diff --git a/Content.Shared/Trigger/Components/Triggers/TriggerOnDidUnequipHandComponent.cs b/Content.Shared/Trigger/Components/Triggers/TriggerOnDidUnequipHandComponent.cs
new file mode 100644
index 0000000000..5c3d2da018
--- /dev/null
+++ b/Content.Shared/Trigger/Components/Triggers/TriggerOnDidUnequipHandComponent.cs
@@ -0,0 +1,10 @@
+using Robust.Shared.GameStates;
+
+namespace Content.Shared.Trigger.Components.Triggers;
+
+/// <summary>
+/// Triggers an entity when it is drops an item from one of its hand slots.
+/// The user is the entity that was dropped.
+/// </summary>
+[RegisterComponent, NetworkedComponent, AutoGenerateComponentState]
+public sealed partial class TriggerOnDidUnequipHandComponent : BaseTriggerOnXComponent;
diff --git a/Content.Shared/Trigger/Components/Triggers/TriggerOnDroppedComponent.cs b/Content.Shared/Trigger/Components/Triggers/TriggerOnDroppedComponent.cs
new file mode 100644
index 0000000000..6e06216a2c
--- /dev/null
+++ b/Content.Shared/Trigger/Components/Triggers/TriggerOnDroppedComponent.cs
@@ -0,0 +1,10 @@
+using Robust.Shared.GameStates;
+
+namespace Content.Shared.Trigger.Components.Triggers;
+
+/// <summary>
+/// Triggers an entity when it is dropped from a users hands, or directly removed from a users inventory, but not when moved between hands & inventory.
+/// The user is the player that was holding or wearing the item.
+/// </summary>
+[RegisterComponent, NetworkedComponent, AutoGenerateComponentState]
+public sealed partial class TriggerOnDroppedComponent : BaseTriggerOnXComponent;
diff --git a/Content.Shared/Trigger/Components/Triggers/TriggerOnGotEquippedHandComponent.cs b/Content.Shared/Trigger/Components/Triggers/TriggerOnGotEquippedHandComponent.cs
new file mode 100644
index 0000000000..24c2d4231c
--- /dev/null
+++ b/Content.Shared/Trigger/Components/Triggers/TriggerOnGotEquippedHandComponent.cs
@@ -0,0 +1,10 @@
+using Robust.Shared.GameStates;
+
+namespace Content.Shared.Trigger.Components.Triggers;
+
+/// <summary>
+/// Triggers an item when it is equipped into a hand slot.
+/// The user is the entity that picked the item up.
+/// </summary>
+[RegisterComponent, NetworkedComponent, AutoGenerateComponentState]
+public sealed partial class TriggerOnGotEquippedHandComponent : BaseTriggerOnXComponent;
diff --git a/Content.Shared/Trigger/Components/Triggers/TriggerOnGotUnequippedHandComponent.cs b/Content.Shared/Trigger/Components/Triggers/TriggerOnGotUnequippedHandComponent.cs
new file mode 100644
index 0000000000..624c1a141b
--- /dev/null
+++ b/Content.Shared/Trigger/Components/Triggers/TriggerOnGotUnequippedHandComponent.cs
@@ -0,0 +1,10 @@
+using Robust.Shared.GameStates;
+
+namespace Content.Shared.Trigger.Components.Triggers;
+
+/// <summary>
+/// Triggers an item when it is dropped from a hand slot.
+/// The user is the entity that dropped the item.
+/// </summary>
+[RegisterComponent, NetworkedComponent, AutoGenerateComponentState]
+public sealed partial class TriggerOnGotUnequippedHandComponent : BaseTriggerOnXComponent;
diff --git a/Content.Shared/Trigger/Systems/HandTriggerSystem.cs b/Content.Shared/Trigger/Systems/HandTriggerSystem.cs
new file mode 100644
index 0000000000..8001d5d92f
--- /dev/null
+++ b/Content.Shared/Trigger/Systems/HandTriggerSystem.cs
@@ -0,0 +1,64 @@
+using Content.Shared.Hands;
+using Content.Shared.Interaction.Events;
+using Content.Shared.Trigger.Components.Triggers;
+using Robust.Shared.Timing;
+
+namespace Content.Shared.Trigger.Systems;
+
+public sealed partial class HandTriggerSystem : EntitySystem
+{
+    [Dependency] private readonly IGameTiming _timing = default!;
+    [Dependency] private readonly TriggerSystem _trigger = default!;
+
+    public override void Initialize()
+    {
+        base.Initialize();
+
+        SubscribeLocalEvent<TriggerOnGotEquippedHandComponent, GotEquippedHandEvent>(OnGotEquipped);
+        SubscribeLocalEvent<TriggerOnGotUnequippedHandComponent, GotUnequippedHandEvent>(OnGotUnequipped);
+        SubscribeLocalEvent<TriggerOnDidEquipHandComponent, DidEquipHandEvent>(OnDidEquip);
+        SubscribeLocalEvent<TriggerOnDidUnequipHandComponent, DidUnequipHandEvent>(OnDidUnequip);
+        SubscribeLocalEvent<TriggerOnDroppedComponent, DroppedEvent>(OnDropped);
+    }
+
+    private void OnGotEquipped(Entity<TriggerOnGotEquippedHandComponent> ent, ref GotEquippedHandEvent args)
+    {
+        // If the entity was equipped on the server (without prediction) then the container change is networked to the client
+        // which will raise the same event, but the effect of the trigger is already networked on its own. So this guard statement
+        // prevents triggering twice on the client.
+        if (_timing.ApplyingState)
+            return;
+
+        _trigger.Trigger(ent.Owner, args.User, ent.Comp.KeyOut);
+    }
+
+    private void OnGotUnequipped(Entity<TriggerOnGotUnequippedHandComponent> ent, ref GotUnequippedHandEvent args)
+    {
+        if (_timing.ApplyingState)
+            return;
+
+        _trigger.Trigger(ent.Owner, args.User, ent.Comp.KeyOut);
+    }
+
+    private void OnDidEquip(Entity<TriggerOnDidEquipHandComponent> ent, ref DidEquipHandEvent args)
+    {
+        if (_timing.ApplyingState)
+            return;
+
+        _trigger.Trigger(ent.Owner, args.Equipped, ent.Comp.KeyOut);
+    }
+
+    private void OnDidUnequip(Entity<TriggerOnDidUnequipHandComponent> ent, ref DidUnequipHandEvent args)
+    {
+        if (_timing.ApplyingState)
+            return;
+
+        _trigger.Trigger(ent.Owner, args.Unequipped, ent.Comp.KeyOut);
+    }
+
+    private void OnDropped(Entity<TriggerOnDroppedComponent> ent, ref DroppedEvent args)
+    {
+        // We don't need the guard statement here because this one is not a container event, but raised directly when interacting.
+        _trigger.Trigger(ent.Owner, args.User, ent.Comp.KeyOut);
+    }
+}