Equip and unequip triggers (#39675)

* added equip and unequip triggers for equipment and equipee

* Update Content.Shared/Trigger/Components/Triggers/TriggerOnDidEquipComponent.cs

---------

Co-authored-by: slarticodefast <161409025+slarticodefast@users.noreply.github.com>

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

@@ -0,0 +1,18 @@
+using Content.Shared.Inventory;
+using Robust.Shared.GameStates;
+
+namespace Content.Shared.Trigger.Components.Triggers;
+
+/// <summary>
+/// Triggers when an entity equips another entity.
+/// The user is the entity being equipped.
+/// </summary>
+[RegisterComponent, NetworkedComponent, AutoGenerateComponentState]
+public sealed partial class TriggerOnDidEquipComponent : BaseTriggerOnXComponent
+{
+    /// <summary>
+    /// The slots entities being equipped to will trigger the entity.
+    /// </summary>
+    [DataField, AutoNetworkedField]
+    public SlotFlags SlotFlags;
+}

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

@@ -0,0 +1,18 @@
+using Content.Shared.Inventory;
+using Robust.Shared.GameStates;
+
+namespace Content.Shared.Trigger.Components.Triggers;
+
+/// <summary>
+/// Triggers when an entity unequips another entity.
+/// The user is the entity being unequipped.
+/// </summary>
+[RegisterComponent, NetworkedComponent, AutoGenerateComponentState]
+public sealed partial class TriggerOnDidUnequipComponent : BaseTriggerOnXComponent
+{
+    /// <summary>
+    /// The slots that entities being unequipped from will trigger the entity.
+    /// </summary>
+    [DataField, AutoNetworkedField]
+    public SlotFlags SlotFlags;
+}

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

@@ -0,0 +1,18 @@
+using Content.Shared.Inventory;
+using Robust.Shared.GameStates;
+
+namespace Content.Shared.Trigger.Components.Triggers;
+
+/// <summary>
+/// Triggers when an entity is equipped to another entity.
+/// The user is the entity being equipped to (i.e. the equipee).
+/// </summary>
+[RegisterComponent, NetworkedComponent, AutoGenerateComponentState]
+public sealed partial class TriggerOnGotEquippedComponent : BaseTriggerOnXComponent
+{
+    /// <summary>
+    /// The slots that being equipped to will trigger the entity.
+    /// </summary>
+    [DataField, AutoNetworkedField]
+    public SlotFlags SlotFlags;
+}

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

@@ -0,0 +1,18 @@
+using Content.Shared.Inventory;
+using Robust.Shared.GameStates;
+
+namespace Content.Shared.Trigger.Components.Triggers;
+
+/// <summary>
+/// Triggers when an entity is unequipped from another entity.
+/// The user is the entity being unequipped from (i.e. the (un)equipee).
+/// </summary>
+[RegisterComponent, NetworkedComponent, AutoGenerateComponentState]
+public sealed partial class TriggerOnGotUnequippedComponent : BaseTriggerOnXComponent
+{
+    /// <summary>
+    /// The slots that being unequipped from will trigger the entity.
+    /// </summary>
+    [DataField, AutoNetworkedField]
+    public SlotFlags SlotFlags;
+}

Content.Shared/Trigger/Systems/TriggerOnEquipmentSystem.cs

@@ -0,0 +1,70 @@
+using Content.Shared.Trigger.Components.Triggers;
+using Robust.Shared.Timing;
+using Content.Shared.Inventory.Events;
+
+namespace Content.Shared.Trigger.Systems;
+
+/// <summary>
+/// System for creating triggers when entities are equipped or unequipped from inventory slots.
+/// </summary>
+public sealed class TriggerOnEquipmentSystem : EntitySystem
+{
+    [Dependency] private readonly TriggerSystem _trigger = default!;
+    [Dependency] private readonly IGameTiming _timing = default!;
+
+    public override void Initialize()
+    {
+        base.Initialize();
+
+        SubscribeLocalEvent<TriggerOnDidEquipComponent, DidEquipEvent>(OnDidEquip);
+        SubscribeLocalEvent<TriggerOnDidUnequipComponent, DidUnequipEvent>(OnDidUnequip);
+        SubscribeLocalEvent<TriggerOnGotEquippedComponent, GotEquippedEvent>(OnGotEquipped);
+        SubscribeLocalEvent<TriggerOnGotUnequippedComponent, GotUnequippedEvent>(OnGotUnequipped);
+    }
+
+    // Used by entities when equipping or unequipping other entities
+    private void OnDidEquip(Entity<TriggerOnDidEquipComponent> ent, ref DidEquipEvent args)
+    {
+        if (_timing.ApplyingState)
+            return;
+
+        if ((ent.Comp.SlotFlags & args.SlotFlags) == 0)
+            return;
+
+        _trigger.Trigger(ent.Owner, args.Equipment, ent.Comp.KeyOut);
+    }
+
+    private void OnDidUnequip(Entity<TriggerOnDidUnequipComponent> ent, ref DidUnequipEvent args)
+    {
+        if (_timing.ApplyingState)
+            return;
+
+        if ((ent.Comp.SlotFlags & args.SlotFlags) == 0)
+            return;
+
+        _trigger.Trigger(ent.Owner, args.Equipment, ent.Comp.KeyOut);
+    }
+
+    // Used by entities when they get equipped or unequipped
+    private void OnGotEquipped(Entity<TriggerOnGotEquippedComponent> ent, ref GotEquippedEvent args)
+    {
+        if (_timing.ApplyingState)
+            return;
+
+        if ((ent.Comp.SlotFlags & args.SlotFlags) == 0)
+            return;
+
+        _trigger.Trigger(ent.Owner, args.Equipee, ent.Comp.KeyOut);
+    }
+
+    private void OnGotUnequipped(Entity<TriggerOnGotUnequippedComponent> ent, ref GotUnequippedEvent args)
+    {
+        if (_timing.ApplyingState)
+            return;
+
+        if ((ent.Comp.SlotFlags & args.SlotFlags) == 0)
+            return;
+
+        _trigger.Trigger(ent.Owner, args.Equipee, ent.Comp.KeyOut);
+    }
+}