feat(D.5.2): ItemInstance.Effects + ItemRepository.UpdateIntProperty

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

src/AcDream.Core/Items/ItemInstance.cs

@@ -136,6 +136,13 @@ public sealed class ItemInstance
     public uint IconId        { get; set; }    // 0x06xxxxxx
     public uint IconUnderlayId{ get; set; }    // "magic" underlay
     public uint IconOverlayId { get; set; }    // "enchanted" overlay
+    /// <summary>
+    /// UiEffects bitfield (retail PublicWeenieDesc._effects, acclient.h:37183).
+    /// Drives the icon's effect-overlay recolor (Magical=0x1 … Nether=0x1000).
+    /// CreateObject-only (weenieFlags 0x80) + live PublicUpdatePropertyInt(0x02CE);
+    /// appraise never carries it. 0 = no effect.
+    /// </summary>
+    public uint Effects       { get; set; }
     public int  StackSize     { get; set; } = 1;
     public int  StackSizeMax  { get; set; } = 1;
     public int  Burden        { get; set; }    // per-stack total

src/AcDream.Core/Items/ItemRepository.cs

@@ -152,7 +152,7 @@ public sealed class ItemRepository
     /// </para>
     /// </summary>
     public bool EnrichItem(uint objectId, uint iconId, string name, ItemType type,
-        uint iconOverlayId = 0, uint iconUnderlayId = 0)
+        uint iconOverlayId = 0, uint iconUnderlayId = 0, uint effects = 0)
     {
         if (!_items.TryGetValue(objectId, out var item)) return false;
         if (iconId != 0) item.IconId = iconId;
@@ -160,6 +160,9 @@ public sealed class ItemRepository
         if (type != default) item.Type = type;
         if (iconOverlayId != 0) item.IconOverlayId = iconOverlayId;
         if (iconUnderlayId != 0) item.IconUnderlayId = iconUnderlayId;
+        // D.5.2: 0 is a meaningful "no effect" state (e.g. a caster out of mana),
+        // so assign unconditionally — re-composition reflects the CURRENT state.
+        item.Effects = effects;
         ItemPropertiesUpdated?.Invoke(item);
         return true;
     }
@@ -184,6 +187,25 @@ public sealed class ItemRepository
         return true;
     }
 
+    /// <summary>PropertyInt.UiEffects (ACE enum value 18) — the icon effect bitfield.</summary>
+    public const uint UiEffectsPropertyId = 18u;
+
+    /// <summary>
+    /// Apply a single PropertyInt update (from PublicUpdatePropertyInt 0x02CE) to an
+    /// item: store it in the bundle and, for known typed ints, mirror to the typed
+    /// field. Today: UiEffects (18) → <see cref="ItemInstance.Effects"/>. Fires
+    /// ItemPropertiesUpdated so bound widgets re-composite. Extensible hook for future
+    /// typed PropertyInts (StackSize, Structure, …). False if the item is unknown.
+    /// </summary>
+    public bool UpdateIntProperty(uint itemId, uint propertyId, int value)
+    {
+        if (!_items.TryGetValue(itemId, out var item)) return false;
+        item.Properties.Ints[propertyId] = value;
+        if (propertyId == UiEffectsPropertyId) item.Effects = (uint)value;
+        ItemPropertiesUpdated?.Invoke(item);
+        return true;
+    }
+
     /// <summary>
     /// Flush the repository — typically called on logoff or teleport
     /// that drops the session's item state.

tests/AcDream.Core.Tests/Items/ItemRepositoryTests.cs

@@ -139,4 +139,36 @@ public sealed class ItemRepositoryTests
         var repo = new ItemRepository();
         Assert.False(repo.EnrichItem(0x9999u, 0x06001234u, "x", ItemType.Misc));
     }
+
+    [Fact]
+    public void EnrichItem_carriesEffects()
+    {
+        var repo = new ItemRepository();
+        repo.AddOrUpdate(new ItemInstance { ObjectId = 0x500000AAu });
+        bool ok = repo.EnrichItem(0x500000AAu, iconId: 0x06001234u, name: "Wand",
+            type: ItemType.Caster, iconOverlayId: 0, iconUnderlayId: 0, effects: 0x1u);
+        Assert.True(ok);
+        Assert.Equal(0x1u, repo.GetItem(0x500000AAu)!.Effects);
+    }
+
+    [Fact]
+    public void UpdateIntProperty_uiEffects_setsEffectsAndFires()
+    {
+        var repo = new ItemRepository();
+        repo.AddOrUpdate(new ItemInstance { ObjectId = 0x500000ABu });
+        ItemInstance? fired = null;
+        repo.ItemPropertiesUpdated += i => fired = i;
+        bool ok = repo.UpdateIntProperty(0x500000ABu, 18u, value: 0x9);   // 18 = UiEffects
+        Assert.True(ok);
+        Assert.Equal(0x9u, repo.GetItem(0x500000ABu)!.Effects);
+        Assert.Equal(0x9, repo.GetItem(0x500000ABu)!.Properties.Ints[18u]);
+        Assert.NotNull(fired);
+    }
+
+    [Fact]
+    public void UpdateIntProperty_unknownItem_returnsFalse()
+    {
+        var repo = new ItemRepository();
+        Assert.False(repo.UpdateIntProperty(0xDEADBEEFu, 18u, 1));
+    }
 }