Handle item tags in recipe ingredients

common/src/main/java/com/viaversion/viabackwards/protocol/v1_21_2to1_21/Protocol1_21_2To1_21.java

@@ -24,6 +24,7 @@ import com.viaversion.viabackwards.api.rewriters.TranslatableRewriter;
 import com.viaversion.viabackwards.protocol.v1_21_2to1_21.rewriter.BlockItemPacketRewriter1_21_2;
 import com.viaversion.viabackwards.protocol.v1_21_2to1_21.rewriter.EntityPacketRewriter1_21_2;
 import com.viaversion.viabackwards.protocol.v1_21_2to1_21.storage.InventoryStateIdStorage;
+import com.viaversion.viabackwards.protocol.v1_21_2to1_21.storage.ItemTagStorage;
 import com.viaversion.viaversion.api.connection.UserConnection;
 import com.viaversion.viaversion.api.minecraft.entities.EntityTypes1_20_5;
 import com.viaversion.viaversion.api.protocol.packet.PacketWrapper;
@@ -65,8 +66,8 @@ public final class Protocol1_21_2To1_21 extends BackwardsProtocol<ClientboundPac
     protected void registerPackets() {
         super.registerPackets();
 
-        tagRewriter.registerGeneric(ClientboundPackets1_21_2.UPDATE_TAGS);
+        registerClientbound(ClientboundPackets1_21_2.UPDATE_TAGS, this::storeTags);
-        tagRewriter.registerGeneric(ClientboundConfigurationPackets1_21.UPDATE_TAGS);
+        registerClientbound(ClientboundConfigurationPackets1_21.UPDATE_TAGS, this::storeTags);
 
         final SoundRewriter<ClientboundPacket1_21_2> soundRewriter = new SoundRewriter<>(this);
         soundRewriter.registerSound1_19_3(ClientboundPackets1_21_2.SOUND);
@@ -94,6 +95,12 @@ public final class Protocol1_21_2To1_21 extends BackwardsProtocol<ClientboundPac
         cancelClientbound(ClientboundPackets1_21_2.MOVE_MINECART_ALONG_TRACK); // TODO
     }
 
+    private void storeTags(final PacketWrapper wrapper) {
+        tagRewriter.getGenericHandler().handle(wrapper);
+        wrapper.resetReader();
+        wrapper.user().get(ItemTagStorage.class).readItemTags(wrapper);
+    }
+
     private void clientInformation(final PacketWrapper wrapper) {
         wrapper.passthrough(Types.STRING); // Locale
         wrapper.passthrough(Types.BYTE); // View distance
@@ -110,6 +117,7 @@ public final class Protocol1_21_2To1_21 extends BackwardsProtocol<ClientboundPac
     public void init(final UserConnection user) {
         addEntityTracker(user, new EntityTrackerBase(user, EntityTypes1_20_5.PLAYER));
         user.put(new InventoryStateIdStorage());
+        user.put(new ItemTagStorage());
     }
 
     @Override

common/src/main/java/com/viaversion/viabackwards/protocol/v1_21_2to1_21/rewriter/BlockItemPacketRewriter1_21_2.java

@@ -20,6 +20,7 @@ package com.viaversion.viabackwards.protocol.v1_21_2to1_21.rewriter;
 import com.viaversion.viabackwards.api.rewriters.BackwardsStructuredItemRewriter;
 import com.viaversion.viabackwards.protocol.v1_21_2to1_21.Protocol1_21_2To1_21;
 import com.viaversion.viabackwards.protocol.v1_21_2to1_21.storage.InventoryStateIdStorage;
+import com.viaversion.viabackwards.protocol.v1_21_2to1_21.storage.ItemTagStorage;
 import com.viaversion.viaversion.api.connection.UserConnection;
 import com.viaversion.viaversion.api.data.MappingData;
 import com.viaversion.viaversion.api.minecraft.HolderSet;
@@ -223,10 +224,20 @@ public final class BlockItemPacketRewriter1_21_2 extends BackwardsStructuredItem
             private Item[] ingredient(final PacketWrapper wrapper) {
                 final HolderSet ingredient = wrapper.read(Types.HOLDER_SET).rewrite(id -> protocol.getMappingData().getNewItemId(id));
                 if (ingredient.hasTagKey()) {
-                    // TODO
+                    final ItemTagStorage tagStorage = wrapper.user().get(ItemTagStorage.class);
+                    final int[] tagEntries = tagStorage.itemTag(ingredient.tagKey());
+                    if (tagEntries == null || tagEntries.length == 0) {
+                        // Most cannot be empty; add a dummy ingredient, though this would only come from bad data
                         return new Item[]{new StructuredItem(1, 1)};
                     }
 
+                    final Item[] items = new Item[tagEntries.length];
+                    for (int i = 0; i < tagEntries.length; i++) {
+                        items[i] = new StructuredItem(tagEntries[i], 1);
+                    }
+                    return items;
+                }
+
                 final int[] ids = ingredient.ids();
                 final Item[] items = new Item[ids.length];
                 for (int i = 0; i < ids.length; i++) {

common/src/main/java/com/viaversion/viabackwards/protocol/v1_21_2to1_21/storage/ItemTagStorage.java

@@ -0,0 +1,56 @@
+/*
+ * This file is part of ViaBackwards - https://github.com/ViaVersion/ViaBackwards
+ * Copyright (C) 2016-2024 ViaVersion and contributors
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+package com.viaversion.viabackwards.protocol.v1_21_2to1_21.storage;
+
+import com.viaversion.viaversion.api.connection.StorableObject;
+import com.viaversion.viaversion.api.protocol.packet.PacketWrapper;
+import com.viaversion.viaversion.api.type.Types;
+import com.viaversion.viaversion.util.Key;
+import java.util.HashMap;
+import java.util.Map;
+import org.checkerframework.checker.nullness.qual.Nullable;
+
+public final class ItemTagStorage implements StorableObject {
+
+    private Map<String, int[]> itemTags = new HashMap<>();
+
+    public int @Nullable [] itemTag(final String key) {
+        return itemTags.get(Key.stripMinecraftNamespace(key));
+    }
+
+    public void readItemTags(final PacketWrapper wrapper) {
+        final int length = wrapper.passthrough(Types.VAR_INT);
+        for (int i = 0; i < length; i++) {
+            final String registryKey = wrapper.passthrough(Types.STRING);
+            final int tagsSize = wrapper.passthrough(Types.VAR_INT);
+
+            final boolean itemRegistry = Key.stripMinecraftNamespace(registryKey).equals("item");
+            if (itemRegistry) {
+                this.itemTags = new HashMap<>(tagsSize);
+            }
+
+            for (int j = 0; j < tagsSize; j++) {
+                final String key = wrapper.passthrough(Types.STRING);
+                final int[] ids = wrapper.passthrough(Types.VAR_INT_ARRAY_PRIMITIVE);
+                if (itemRegistry) {
+                    this.itemTags.put(Key.stripMinecraftNamespace(key), ids);
+                }
+            }
+        }
+    }
+}