Fix CUSTOM_DATA handling to properly restore original data in 1.20.5-…

…>1.20.3

Counterpart PR of ViaVersion/ViaVersion#4094; Adds the now required handling of custom data. Ideally we shouldn't backup any tags at all since it prevents mods from edit them, but that would require more conversion code in both protocols.

common/src/main/java/com/viaversion/viabackwards/protocol/v1_20_5to1_20_3/rewriter/BlockItemPacketRewriter1_20_5.java

@@ -30,6 +30,7 @@
 import com.viaversion.viaversion.api.minecraft.Holder;
 import com.viaversion.viaversion.api.minecraft.Particle;
 import com.viaversion.viaversion.api.minecraft.SoundEvent;
+import com.viaversion.viaversion.api.minecraft.data.StructuredData;
 import com.viaversion.viaversion.api.minecraft.data.StructuredDataContainer;
 import com.viaversion.viaversion.api.minecraft.data.StructuredDataKey;
 import com.viaversion.viaversion.api.minecraft.item.Item;
@@ -363,7 +364,15 @@ private static int colorId(final String color) {
             data.set(StructuredDataKey.FIREWORKS, new Fireworks(1, new FireworkExplosion[0]));
         }
 
+        final StructuredData<CompoundTag> customData = data.getNonEmpty(StructuredDataKey.CUSTOM_DATA);
         final Item oldItem = vvProtocol.getItemRewriter().toOldItem(connection, item, DATA_CONVERTER);
+
+        if (customData != null) {
+            // We later don't know which tags are custom data and which are not because the VV conversion
+            // keeps converted data, so we backup the original custom data and restore it later
+            oldItem.tag().put(nbtTagName(), customData.value().copy());
+        }
+
         if (oldItem.tag() != null && oldItem.tag().isEmpty()) {
             // Improve item equality checks by removing empty tags
             oldItem.setTag(null);
@@ -386,9 +395,14 @@ public Item handleItemToServer(final UserConnection connection, @Nullable final
         // Convert to structured item first
         final Item structuredItem = vvProtocol.getItemRewriter().toStructuredItem(connection, item);
 
+        if (item.tag() != null && item.tag().get(nbtTagName()) instanceof final CompoundTag tag) {
+            // Set original custom data from backup
+            structuredItem.dataContainer().set(StructuredDataKey.CUSTOM_DATA, tag);
+        }
+
         structuredItem.dataContainer().setIdLookup(protocol, false);
         enchantmentRewriter.handleToServer(structuredItem);
 
         return super.handleItemToServer(connection, structuredItem);
     }
-}
+}

gradle.properties

@@ -1,4 +1,4 @@
-projectVersion=5.0.3
+projectVersion=5.0.4-SNAPSHOT
 
 # Smile emoji
 mcVersions=1.21,1.20.6,1.20.5,1.20.4, 1.20.3, 1.20.2, 1.20.1, 1.20, 1.19.4, 1.19.3, 1.19.2, 1.19.1, 1.19, 1.18.2, 1.18.1, 1.18, 1.17.1, 1.17, 1.16.5, 1.16.4, 1.16.3, 1.16.2, 1.16.1, 1.16, 1.15.2, 1.15.1, 1.15, 1.14.4, 1.14.3, 1.14.2, 1.14.1, 1.14, 1.13.2, 1.13.1, 1.13, 1.12.2, 1.12.1, 1.12, 1.11.2, 1.11.1, 1.11, 1.10.2, 1.10.1, 1.10