Add multiblock traits and syncable traits

src/main/java/com/gregtechceu/gtceu/api/machine/multiblock/MultiblockControllerMachine.java

@@ -8,6 +8,7 @@
 import com.gregtechceu.gtceu.api.machine.MultiblockMachineDefinition;
 import com.gregtechceu.gtceu.api.machine.feature.multiblock.IMultiPart;
 import com.gregtechceu.gtceu.api.machine.property.GTMachineModelProperties;
+import com.gregtechceu.gtceu.api.machine.trait.MultiblockMachineTrait;
 import com.gregtechceu.gtceu.api.pattern.BlockPattern;
 import com.gregtechceu.gtceu.api.pattern.MultiblockState;
 import com.gregtechceu.gtceu.api.pattern.MultiblockWorldSavedData;
@@ -123,6 +124,12 @@ public void onStructureFormed() {
             }
             part.addedToController(this);
         }
+        updatePartPositions();
+
+        for (var trait : getTraitHolder().getAllTraits()) {
+            if (trait instanceof MultiblockMachineTrait multiblockMachineTrait)
+                multiblockMachineTrait.onStructureFormed();
+        }
     }
 
     /**
@@ -147,6 +154,11 @@ public void onStructureInvalid() {
         parallelHatch = null;
         parts.clear();
         updatePartPositions();
+
+        for (var trait : getTraitHolder().getAllTraits()) {
+            if (trait instanceof MultiblockMachineTrait multiblockMachineTrait)
+                multiblockMachineTrait.onStructureInvalid();
+        }
     }
 
     /**

src/main/java/com/gregtechceu/gtceu/api/machine/trait/MachineTraitHolder.java

@@ -1,6 +1,12 @@
 package com.gregtechceu.gtceu.api.machine.trait;
 
+import com.gregtechceu.gtceu.GTCEu;
 import com.gregtechceu.gtceu.api.machine.MetaMachine;
+import com.gregtechceu.gtceu.api.sync_system.data_transformers.ValueTransformer;
+import com.gregtechceu.gtceu.api.sync_system.data_transformers.ValueTransformers;
+
+import net.minecraft.nbt.CompoundTag;
+import net.minecraft.nbt.Tag;
 
 import it.unimi.dsi.fastutil.objects.Object2ObjectOpenHashMap;
 import it.unimi.dsi.fastutil.objects.ObjectArrayList;
@@ -10,6 +16,7 @@
 import java.util.Collections;
 import java.util.List;
 import java.util.Map;
+import java.util.Objects;
 import java.util.Optional;
 
 public final class MachineTraitHolder {
@@ -18,10 +25,13 @@ public final class MachineTraitHolder {
     private final List<MachineTrait> traits;
     private final Map<MachineTraitType<?>, List<MachineTrait>> traitsByType;
 
+    private final Map<String, MachineTrait> traitsToSave;
+
     public MachineTraitHolder(MetaMachine machine) {
         this.machine = machine;
         this.traits = new ObjectArrayList<>();
         this.traitsByType = new Object2ObjectOpenHashMap<>();
+        this.traitsToSave = new Object2ObjectOpenHashMap<>();
     }
 
     public @UnmodifiableView List<MachineTrait> getAllTraits() {
@@ -40,6 +50,28 @@ public void attachTrait(MachineTrait trait) {
         traits.add(trait);
     }
 
+    /**
+     * Registers a trait to be synced/saved.
+     * Do not register a trait to be synced and also store that trait as a syncable machine field, otherwise the trait
+     * data will be duplicated. Use only one sync method.
+     *
+     * @param traitName Unique identifier for this trait.
+     * @param trait     The trait to register
+     */
+    public MachineTraitHolder syncTrait(String traitName, MachineTrait trait) {
+        if (trait.machine != machine) throw new IllegalArgumentException("Trait does not belong to this machine.");
+        if (traitsToSave.containsKey(traitName))
+            throw new IllegalArgumentException("Attempted to register duplicate trait save key \"" + traitName + "\"");
+        traitsToSave.put(traitName, trait);
+        return this;
+    }
+
+    @SuppressWarnings("unchecked")
+    public @Nullable <T extends MachineTrait> T getSyncTrait(String traitName) {
+        MachineTrait trait = traitsToSave.get(traitName);
+        return trait == null ? null : (T) trait;
+    }
+
     /**
      * Gets the first trait with the specified type.
      */
@@ -62,4 +94,39 @@ public <T extends MachineTrait> Optional<T> getTraitOptional(MachineTraitType<T>
         if (traitList == null) return List.of();
         return Collections.unmodifiableList(traitList);
     }
+
+    private static class MachineTraitHolderTransformer implements ValueTransformer<MachineTraitHolder> {
+
+        @Override
+        public Tag serializeNBT(MachineTraitHolder value, TransformerContext<MachineTraitHolder> context) {
+            CompoundTag tag = new CompoundTag();
+
+            value.traitsToSave.forEach((k, v) -> tag.put(k,
+                    v.getSyncDataHolder().serializeNBT(context.isClientSync(), context.isClientFullSyncUpdate())));
+
+            return tag;
+        }
+
+        @Override
+        public @Nullable MachineTraitHolder deserializeNBT(Tag tag, TransformerContext<MachineTraitHolder> context) {
+            var traitHolder = Objects.requireNonNull(context.currentValue());
+            var compoundTag = (CompoundTag) tag;
+
+            for (var key : compoundTag.getAllKeys()) {
+                var trait = traitHolder.getSyncTrait(key);
+                if (trait == null) {
+                    GTCEu.LOGGER.warn("Attempted to deserialise syncable trait '{}', but no syncable trait has that ID",
+                            key);
+                    continue;
+                }
+                trait.getSyncDataHolder().deserializeNBT(compoundTag.getCompound("key"), context.isClientSync());
+            }
+
+            return null;
+        }
+    }
+
+    static {
+        ValueTransformers.registerTransformer(MachineTraitHolder.class, new MachineTraitHolderTransformer());
+    }
 }

src/main/java/com/gregtechceu/gtceu/api/machine/trait/MultiblockMachineTrait.java

@@ -0,0 +1,14 @@
+package com.gregtechceu.gtceu.api.machine.trait;
+
+import com.gregtechceu.gtceu.api.machine.multiblock.MultiblockControllerMachine;
+
+public abstract class MultiblockMachineTrait extends MachineTrait {
+
+    public MultiblockMachineTrait(MultiblockControllerMachine multiMachine) {
+        super(multiMachine);
+    }
+
+    public void onStructureFormed() {}
+
+    public void onStructureInvalid() {}
+}

src/main/java/com/gregtechceu/gtceu/api/sync_system/SyncDataHolder.java

@@ -59,7 +59,7 @@ public CompoundTag serializeNBT(boolean writeClientFields, boolean fullSync) {
         CompoundTag tag = new CompoundTag();
         for (var field : fieldsToSerialize) {
             if (shouldSerializeField(field, writeClientFields, fullSync)) {
-                Tag nbtValue = serializeField(holder, field, writeClientFields);
+                Tag nbtValue = serializeField(holder, field, writeClientFields, fullSync);
                 tag.put(field.nbtSaveKey, nbtValue);
             }
         }
@@ -101,7 +101,7 @@ public void deserializeNBT(CompoundTag tag, boolean readingClientFields) {
 
     @SuppressWarnings("unchecked")
     private static Tag serializeField(ISyncManaged holder, FieldSyncData field,
-                                      boolean writeClientFields) {
+                                      boolean writeClientFields, boolean fullSync) {
         Object currentValue = field.handle.get(holder);
 
         if (!field.isSyncManaged && currentValue == null) {
@@ -115,7 +115,7 @@ private static Tag serializeField(ISyncManaged holder, FieldSyncData field,
             if (field.transformer != null) {
                 return ((ValueTransformer<Object>) field.transformer).serializeNBT(currentValue,
                         new ValueTransformer.TransformerContext<>(holder, field.type, currentValue, field.fieldName,
-                                writeClientFields));
+                                writeClientFields, fullSync));
             } else if (currentValue instanceof ISyncManaged syncObj) {
                 return syncObj.getSyncDataHolder().serializeNBT(writeClientFields);
             } else {
@@ -150,7 +150,7 @@ private static void deserializeField(ISyncManaged holder, FieldSyncData field,
                 try {
                     var current = field.handle.get(holder);
                     Object result = transformer.deserializeNBT(savedValue, new ValueTransformer.TransformerContext<>(
-                            holder, field.type, current, field.fieldName, readingClientFields));
+                            holder, field.type, current, field.fieldName, readingClientFields, false));
                     if (result != current) {
                         field.handle.set(holder, result);
                     }
@@ -175,4 +175,20 @@ private static void deserializeField(ISyncManaged holder, FieldSyncData field,
             GTCEu.LOGGER.error(e);
         }
     }
+
+    public static class SyncManagedTransformer implements ValueTransformer<ISyncManaged> {
+
+        @Override
+        public Tag serializeNBT(ISyncManaged value, TransformerContext<ISyncManaged> context) {
+            return value.getSyncDataHolder().serializeNBT(context.isClientSync(), context.isClientFullSyncUpdate());
+        }
+
+        @Override
+        public @Nullable ISyncManaged deserializeNBT(Tag tag, TransformerContext<ISyncManaged> context) {
+            ISyncManaged syncManaged = context.currentValue();
+            Objects.requireNonNull(syncManaged).getSyncDataHolder().deserializeNBT((CompoundTag) tag,
+                    context.isClientSync());
+            return syncManaged;
+        }
+    }
 }

src/main/java/com/gregtechceu/gtceu/api/sync_system/data_transformers/ValueTransformer.java

@@ -25,11 +25,12 @@ public interface ValueTransformer<T> {
      * @param fieldName    The name of the field being serialized, or a string denoting the current sync context if not
      *                     being invoked directly on a field.
      * @param isClientSync Whether NBT is currently being generated as part of a sync update to the client, not as NBT
-     *                     being
-     *                     written to the server save.
+     *                     being written to the server save.
+     *
      */
     record TransformerContext<U>(@NotNull ISyncManaged holder, @NotNull TypeDeclaration type,
-                                 @Nullable U currentValue, @Nullable String fieldName, boolean isClientSync) {}
+                                 @Nullable U currentValue, @Nullable String fieldName, boolean isClientSync,
+                                 boolean isClientFullSyncUpdate) {}
 
     /**
      * Casts a given NBT tag to a specific tag type, throwing an error if the tag cannot be casted.

src/main/java/com/gregtechceu/gtceu/api/sync_system/data_transformers/ValueTransformers.java

@@ -6,6 +6,8 @@
 import com.gregtechceu.gtceu.api.recipe.GTRecipe;
 import com.gregtechceu.gtceu.api.recipe.GTRecipeType;
 import com.gregtechceu.gtceu.api.registry.GTRegistries;
+import com.gregtechceu.gtceu.api.sync_system.ISyncManaged;
+import com.gregtechceu.gtceu.api.sync_system.SyncDataHolder;
 import com.gregtechceu.gtceu.api.sync_system.TypeDeclaration;
 import com.gregtechceu.gtceu.api.sync_system.data_transformers.collections.ListTransformer;
 import com.gregtechceu.gtceu.api.sync_system.data_transformers.collections.MapTransformer;
@@ -177,6 +179,7 @@ public static <T> void registerTransformerSupplier(Class<T> type, Supplier<Value
                 }, StringTag.class);
 
         registerTransformer(INBTSerializable.class, new NBTSerializableTransformer());
+        registerTransformer(ISyncManaged.class, new SyncDataHolder.SyncManagedTransformer());
 
         registerTransformerSupplier(List.class, ListTransformer::new);
         registerTransformerSupplier(Map.class, MapTransformer::new);

src/main/java/com/gregtechceu/gtceu/api/sync_system/data_transformers/collections/ListTransformer.java

@@ -33,7 +33,7 @@ private ValueTransformer.TransformerContext<T> getInnerElemContext(@Nullable T e
                                                                        ValueTransformer.TransformerContext<List<T>> parentContext) {
         return new TransformerContext<>(parentContext.holder(),
                 parentContext.type().getGenericTypeArgs()[0], elem, parentContext.fieldName() + "[element]",
-                parentContext.isClientSync());
+                parentContext.isClientSync(), parentContext.isClientFullSyncUpdate());
     }
 
     @Override

src/main/java/com/gregtechceu/gtceu/api/sync_system/data_transformers/collections/MapTransformer.java

@@ -48,15 +48,15 @@ private ValueTransformer.TransformerContext<K> getInnerKeyContext(@Nullable K ke
                                                                       ValueTransformer.TransformerContext<Map<K, V>> parentContext) {
         return new TransformerContext<>(parentContext.holder(),
                 parentContext.type().getGenericTypeArgs()[0], key, parentContext.fieldName() + "[key]",
-                parentContext.isClientSync());
+                parentContext.isClientSync(), parentContext.isClientFullSyncUpdate());
     }
 
     private ValueTransformer.TransformerContext<V> getInnerValueContext(@Nullable V value,
                                                                         ValueTransformer.TransformerContext<Map<K, V>> parentContext) {
         return new TransformerContext<>(parentContext.holder(),
                 parentContext.type().getGenericTypeArgs()[1], value,
                 parentContext.fieldName() + "[value]",
-                parentContext.isClientSync());
+                parentContext.isClientSync(), parentContext.isClientFullSyncUpdate());
     }
 
     @Override

src/main/java/com/gregtechceu/gtceu/api/sync_system/data_transformers/collections/ObjectArrayTransformer.java

@@ -23,7 +23,7 @@ private ValueTransformer.TransformerContext<T> getInnerElemContext(@Nullable T e
                                                                        ValueTransformer.TransformerContext<T[]> parentContext) {
         return new TransformerContext<>(parentContext.holder(),
                 parentContext.type().getArrayComponentType(), elem, parentContext.fieldName() + "[element]",
-                parentContext.isClientSync());
+                parentContext.isClientSync(), parentContext.isClientFullSyncUpdate());
     }
 
     @Override

src/main/java/com/gregtechceu/gtceu/api/sync_system/data_transformers/collections/SetTransformer.java

@@ -33,7 +33,7 @@ private ValueTransformer.TransformerContext<T> getInnerElemContext(@Nullable T e
                                                                        ValueTransformer.TransformerContext<Set<T>> parentContext) {
         return new TransformerContext<>(parentContext.holder(),
                 parentContext.type().getGenericTypeArgs()[0], elem, parentContext.fieldName() + "[element]",
-                parentContext.isClientSync());
+                parentContext.isClientSync(), parentContext.isClientSync());
     }
 
     @Override