fix(inventory): sequence secondary wield blockers

Preserve retail AmmoType from CreateObject and port BlocksUseOfShield so bow, caster, and two-handed switches remove incompatible shields, while mismatched missile ammo is also returned to the pack. Each blocker remains server-confirmed before AutoWield re-enters.

Co-Authored-By: Codex <codex@openai.com>

src/AcDream.App/UI/AutoWieldController.cs

@@ -19,6 +19,9 @@ internal sealed class AutoWieldController : IDisposable
         | EquipMask.Held
         | EquipMask.TwoHanded;
 
+    private const byte CombatUseMissile = 0x02;
+    private const byte CombatUseTwoHanded = 0x05;
+
     private static readonly EquipMask[] AutoEquipOrder =
     {
         EquipMask.HeadWear,
@@ -105,6 +108,20 @@ internal sealed class AutoWieldController : IDisposable
             if (blocker is not null)
                 return BeginWeaponReplacement(item.ObjectId, blocker.ObjectId);
 
+            // Retail checks secondary blockers only after the primary weapon
+            // slot is vacant, then re-enters AutoWield after each confirmed
+            // move. ACCWeenieObject::BlocksUseOfShield @ 0x0055D3E0.
+            if (BlocksUseOfShield(item)
+                && GetEquippedObjectAtLocation(
+                    EquipMask.Shield, priority: 0, item.ObjectId) is { } shield)
+                return BeginWeaponReplacement(item.ObjectId, shield.ObjectId);
+
+            if (item.AmmoType is > 0
+                && GetEquippedObjectAtLocation(
+                    EquipMask.MissileAmmo, priority: 0, item.ObjectId) is { } ammo
+                && ammo.AmmoType != item.AmmoType)
+                return BeginWeaponReplacement(item.ObjectId, ammo.ObjectId);
+
             return SendWield(item, weaponLocation);
         }
 
@@ -270,6 +287,14 @@ internal sealed class AutoWieldController : IDisposable
             && (item.WielderId == player || item.ContainerId == player);
     }
 
+    internal static bool BlocksUseOfShield(ClientObject item)
+    {
+        byte combatUse = item.CombatUse ?? 0;
+        return combatUse == CombatUseTwoHanded
+            || (combatUse == CombatUseMissile && item.AmmoType is > 0)
+            || item.Type.HasFlag(ItemType.Caster);
+    }
+
     public void Dispose()
     {
         if (_disposed)

src/AcDream.Core.Net/Messages/CreateObject.cs

@@ -205,7 +205,10 @@ public static class CreateObject
         // ACCWeenieObject::GetObjectName(NAME_APPROPRIATE) selects this for stacks.
         string? PluralName = null,
         // PublicWeenieDesc._pet_owner, gated by second-header flag 0x8.
-        uint? PetOwnerId = null);
+        uint? PetOwnerId = null,
+        // PublicWeenieDesc._ammoType, gated by WeenieHeader flag 0x100.
+        // AMMO_NONE is the explicit wire value zero; null means absent.
+        ushort? AmmoType = null);
 
     /// <summary>
     /// The relevant subset of the server-sent <c>MovementData</c> /
@@ -772,6 +775,7 @@ public static class CreateObject
             byte? radarBlipColor = null;
             byte? radarBehavior = null;
             byte? combatUse = null;
+            ushort? ammoType = null;
             uint iconOverlayId = 0;
             uint iconUnderlayId = 0;
             uint uiEffects = 0;
@@ -810,6 +814,7 @@ public static class CreateObject
                 if ((weenieFlags & 0x00000100u) != 0)         // AmmoType u16
                 {
                     if (body.Length - pos < 2) throw new FormatException("trunc AmmoType");
+                    ammoType = BinaryPrimitives.ReadUInt16LittleEndian(body.Slice(pos));
                     pos += 2;
                 }
                 if ((weenieFlags & 0x00000008u) != 0)         // Value u32
@@ -1020,7 +1025,8 @@ public static class CreateObject
                 RadarBlipColor: radarBlipColor, RadarBehavior: radarBehavior,
                 CombatUse: combatUse,
                 PluralName: pluralName,
-                PetOwnerId: petOwnerId);
+                PetOwnerId: petOwnerId,
+                AmmoType: ammoType);
 
             // Local helper: if we ran out of fields past PhysicsData, still
             // return the useful prefix (guid/position/setup/animParts/textures/palettes/scale/motion).

src/AcDream.Core.Net/ObjectTableWiring.cs

@@ -89,5 +89,6 @@ public static class ObjectTableWiring
         PublicWeenieBitfield: s.ObjectDescriptionFlags,
         CombatUse: s.CombatUse,
         PluralName: s.PluralName,
-        PetOwnerId: s.PetOwnerId);
+        PetOwnerId: s.PetOwnerId,
+        AmmoType: s.AmmoType);
 }

src/AcDream.Core.Net/WorldSession.cs

@@ -129,7 +129,8 @@ public sealed class WorldSession : IDisposable
         byte? RadarBehavior = null,
         byte? CombatUse = null,
         string? PluralName = null,
-        uint? PetOwnerId = null);
+        uint? PetOwnerId = null,
+        ushort? AmmoType = null);
 
     /// <summary>
     /// Projects the wire-level CreateObject result into the stable session
@@ -187,7 +188,8 @@ public sealed class WorldSession : IDisposable
         RadarBehavior: parsed.RadarBehavior,
         CombatUse: parsed.CombatUse,
         PluralName: parsed.PluralName,
-        PetOwnerId: parsed.PetOwnerId);
+        PetOwnerId: parsed.PetOwnerId,
+        AmmoType: parsed.AmmoType);
 
     /// <summary>Fires when the session finishes parsing a CreateObject.</summary>
     public event Action<EntitySpawn>? EntitySpawned;

src/AcDream.Core/Items/ClientObject.cs

@@ -189,6 +189,8 @@ public sealed class ClientObject
     public uint PetOwnerId { get; set; }
     /// <summary>Retail <c>PublicWeenieDesc._combatUse</c>; null when its header flag was absent.</summary>
     public byte? CombatUse { get; set; }
+    /// <summary>Retail <c>PublicWeenieDesc._ammoType</c>; zero is <c>AMMO_NONE</c>.</summary>
+    public ushort? AmmoType { get; set; }
     /// <summary>Client-side trade state used by ItemHolder legality gates.</summary>
     public int TradeState { get; set; }
     /// <summary>Resolved membership in SpellComponentTable (retail IsComponentPack).</summary>
@@ -255,7 +257,8 @@ public readonly record struct WeenieData(
     uint? PublicWeenieBitfield = null,
     byte? CombatUse = null,
     string? PluralName = null,
-    uint? PetOwnerId = null);
+    uint? PetOwnerId = null,
+    ushort? AmmoType = null);
 
 /// <summary>
 /// Retail ITEM_USEABLE helpers (acclient.h:6478, ItemUses::* at 0x004fccd0).

src/AcDream.Core/Items/ClientObjectTable.cs

@@ -436,6 +436,7 @@ public sealed class ClientObjectTable
         if (d.PublicWeenieBitfield is { } bitfield) obj.PublicWeenieBitfield = bitfield;
         if (d.PetOwnerId is { } petOwnerId) obj.PetOwnerId = petOwnerId;
         if (d.CombatUse is { } combatUse) obj.CombatUse = combatUse;
+        if (d.AmmoType is { } ammoType) obj.AmmoType = ammoType;
         if (d.RadarBlipColor is { } radarBlipColor) obj.RadarBlipColor = radarBlipColor;
         if (d.RadarBehavior is { } radarBehavior) obj.RadarBehavior = radarBehavior;
         if (d.ItemsCapacity is { } ic) obj.ItemsCapacity = ic;