Add event publishing for inventory and combat interactions

GameCore/Combat/DamageSystem.cs

@@ -34,5 +34,8 @@ public class DamageSystem : ISystem
     {
         var targetAttributes = _world.GetComponent<AttributeComponent>(e.Target);
         targetAttributes?.ModifyValue(Attribute.Health, -e.Amount);
+
+        var newHealth = targetAttributes?.GetValue(Attribute.Health) ?? 0f;
+        _world.PublishEvent(new EntityDamagedEvent(e.Target, newHealth, e.Amount));
     }
 }

GameCore/Combat/Effects/ConsumeAmmoCost.cs

@@ -1,4 +1,5 @@
 using GameCore.Combat.Interfaces;
+using GameCore.Events;
 using GameCore.Inventory;
 
 namespace GameCore.Combat.Effects;
@@ -8,7 +9,12 @@ public class ConsumeAmmoCost(string ammoId, int amount) : ICostEffect
     public void Execute(EffectContext context)
     {
         var inventory = context.World.GetComponent<InventoryComponent>(context.Owner);
-        inventory?.RemoveItem(ammoId, amount);
+        if (inventory == null) return;
+
+        inventory.RemoveItem(ammoId, amount);
+
+        var newQuantity = inventory.GetItemCount(ammoId);
+        context.World.PublishEvent(new InventoryItemChangedEvent(context.Owner, ammoId, newQuantity));
     }
 
     public bool CanAfford(EffectContext context)

GameCore/Combat/Effects/HitscanEffect.cs

@@ -1,4 +1,5 @@
 using GameCore.Combat.Interfaces;
+using GameCore.Events;
 using GameCore.Input;
 
 namespace GameCore.Combat.Effects;
@@ -12,8 +13,11 @@ public class HitscanEffect(float range) : IEffect
 
         if (input == null || weapon == null) return;
 
-        var targetPos = input.MuzzlePosition + input.MuzzleDirection * range;
+        var fromPos = input.MuzzlePosition;
-        var hit = context.World.WorldQuery.Raycast(input.MuzzlePosition, targetPos, context.Owner);
+        var targetPos = fromPos + input.MuzzleDirection * range;
+        var hit = context.World.WorldQuery.Raycast(fromPos, targetPos, context.Owner);
+
+        context.World.PublishEvent(new HitscanImpactEvent(context.Owner, fromPos, targetPos, hit));
 
         if (hit.DidHit)
         {

GameCore/Combat/ProjectileSystem.cs

@@ -1,6 +1,7 @@
 using GameCore.Combat.Effects;
 using GameCore.ECS;
 using GameCore.ECS.Interfaces;
+using GameCore.Events;
 using GameCore.Physics;
 
 namespace GameCore.Combat;
@@ -24,6 +25,7 @@ public class ProjectileSystem : ISystem
             var hit = world.WorldQuery.Raycast(position.Position, newPosition, projectileData.Owner);
             if (hit.DidHit)
             {
+                world.PublishEvent(new ProjectileImpactEvent(projectile, hit));
                 var hitContext = new EffectContext
                 {
                     World = world,

GameCore/ECS/HitResult.cs

@@ -1,7 +1,11 @@
+using GameCore.Math;
+
 namespace GameCore.ECS;
 
 public struct HitResult
 {
     public bool DidHit;
-    public Entity HitEntity;
+    public Entity? HitEntity;
+    public Vector3 Position;
+    public Vector3 Normal;
 }

GameCore/Events/EntityDamagedEvent.cs

@@ -0,0 +1,11 @@
+using GameCore.ECS;
+using GameCore.Events.Interfaces;
+
+namespace GameCore.Events;
+
+public readonly struct EntityDamagedEvent(Entity target, float newHealth, float damageTaken) : IEvent
+{
+    public readonly Entity Target = target;
+    public readonly float NewHealth = newHealth;
+    public readonly float DamageTaken = damageTaken;
+}

GameCore/Events/HitscanImpactEvent.cs

@@ -0,0 +1,13 @@
+using GameCore.ECS;
+using GameCore.Events.Interfaces;
+using GameCore.Math;
+
+namespace GameCore.Events;
+
+public readonly struct HitscanImpactEvent(Entity owner, Vector3 from, Vector3 to, HitResult hit) : IEvent
+{
+    public readonly Entity Owner = owner;
+    public readonly Vector3 From = from;
+    public readonly Vector3 To = to;
+    public readonly HitResult Hit = hit;
+}

GameCore/Events/InstantItemUsedEvent.cs

@@ -0,0 +1,10 @@
+using GameCore.ECS;
+using GameCore.Events.Interfaces;
+
+namespace GameCore.Events;
+
+public readonly struct InstantItemUsedEvent(Entity picker, string itemId) : IEvent
+{
+    public readonly Entity Picker = picker;
+    public readonly string ItemId = itemId;
+}

GameCore/Events/InventoryItemChangedEvent.cs

@@ -0,0 +1,11 @@
+using GameCore.ECS;
+using GameCore.Events.Interfaces;
+
+namespace GameCore.Events;
+
+public readonly struct InventoryItemChangedEvent(Entity owner, string itemId, int newQuantity) : IEvent
+{
+    public readonly Entity Owner = owner;
+    public readonly string ItemId = itemId;
+    public readonly int NewQuantity = newQuantity;
+}

GameCore/Events/ProjectileImpactEvent.cs

@@ -0,0 +1,10 @@
+using GameCore.ECS;
+using GameCore.Events.Interfaces;
+
+namespace GameCore.Events;
+
+public readonly struct ProjectileImpactEvent(Entity projectile, HitResult hit) : IEvent
+{
+    public readonly Entity ProjectileEntity = projectile;
+    public readonly HitResult Hit = hit;
+}

GameCore/Events/WeaponEquippedEvent.cs

@@ -0,0 +1,10 @@
+using GameCore.ECS;
+using GameCore.Events.Interfaces;
+
+namespace GameCore.Events;
+
+public readonly struct WeaponEquippedEvent(Entity owner, string newWeaponItemId) : IEvent
+{
+    public readonly Entity Owner = owner;
+    public readonly string NewWeaponItemId = newWeaponItemId;
+}

GameCore/Inventory/InventorySystem.cs

@@ -21,6 +21,10 @@ public class InventorySystem : ISystem
     private void OnAddItem(AddItemToInventoryEvent e)
     {
         var inventory = _world.GetComponent<InventoryComponent>(e.Target);
-        inventory?.AddItem(e.Item);
+        if (inventory == null) return;
+        inventory.AddItem(e.Item);
+
+        var newQuantity = inventory.GetItemCount(e.Item.ItemId);
+        _world.PublishEvent(new InventoryItemChangedEvent(e.Target, e.Item.ItemId, newQuantity));
     }
 }

GameCore/Inventory/ItemAcquisitionSystem.cs

@@ -27,6 +27,7 @@ public class ItemAcquisitionSystem : ISystem
 
         if (pickupComponent.IsInstantUse)
         {
+            _world.PublishEvent(new InstantItemUsedEvent(e.Picker, e.ItemId));
             var context = new EffectContext
             {
                 World = _world,

GameCore/Player/EquipmentSystem.cs

@@ -38,5 +38,7 @@ public class EquipmentSystem : ISystem
         weaponComponent.OnFireEffects = newData.OnFireEffects;
         weaponComponent.OnHitEffects = newData.OnHitEffects;
         weaponComponent.CooldownTimer = 0f;
+
+        _world.PublishEvent(new WeaponEquippedEvent(e.Owner, e.NewWeaponItemId));
     }
 }