Implement AnvilChunkLoader coupling

src/main/java/com/falsepattern/chunk/api/ChunkDataManager.java

@@ -1,62 +1,122 @@
 package com.falsepattern.chunk.api;
 
-import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Contract;
 
 import net.minecraft.nbt.NBTTagCompound;
+import net.minecraft.world.chunk.Chunk;
+import net.minecraft.world.chunk.storage.ExtendedBlockStorage;
 
 import java.nio.ByteBuffer;
 
 /**
- * Singleton instances that can manage custom in chunks.
- * <p>
- * Implementations should be stateless and thread-safe.
- * @implNote For performance reasons, you should store any data in the chunk itself using a mixin. The type T is the type
- * of the interface that you are mixing into the chunk.
+ * Singleton instances that can manage custom in chunks. This class only manages the registration of
+ * managers. For the actual networking and data storage, see the internal interfaces of this interface.
+ * Note: This interface does nothing by itself, you also need to implement one or more of the internal interfaces.
+ * One class can have multiple
  */
-public interface ChunkDataManager<T> {
+public interface ChunkDataManager {
 
     /**
      * @return The domain of this manager. Usually the modid of the mod that owns this manager.
      */
+    @Contract(pure = true)
     String domain();
 
     /**
      * @return The id of this manager. Usually the name of the manager. Unique per domain.
      */
+
+    @Contract(pure = true)
     String id();
 
     /**
-     * @implNote This is used to determine the size of the packet compression/decompression buffer.
-     * @return The maximum amount of bytes your data can take up in a packet.
+     * Implement this interface if you want to synchronize your data with the client.
      */
-    int maxPacketSize();
+    interface PacketDataManager extends ChunkDataManager {
+        /**
+         * @implNote This is used to determine the size of the packet compression/decompression buffer.
+         * @return The maximum amount of bytes your data can take up in a packet.
+         */
+        @Contract(pure = true)
+        int maxPacketSize();
+
+        /**
+         * Serializes your data into a packet.
+         *
+         * @param chunk The chunk to serialize.
+         */
+        void writeToBuffer(Chunk chunk, int ebsMask, boolean forceUpdate, ByteBuffer data);
+
+        /**
+         * Deserializes your data from a packet.
+         * Mutates this object.
+         *
+         * @param chunk  The chunk to deserialize.
+         * @param buffer The packet buffer to read from.
+         */
+        void readFromBuffer(Chunk chunk, int ebsMask, boolean forceUpdate, ByteBuffer buffer);
+    }
 
     /**
-     * Serializes your data into a packet.
-     *
-     * @param chunk The chunk to serialize.
+     * Implement this interface if you want to save your data to disk. This is called once per chunk.
      */
-    void writeToBuffer(T chunk, int ebsMask, boolean forceUpdate, ByteBuffer data);
+    interface ChunkNBTDataManager extends ChunkDataManager {
+        /**
+         * If false, the given nbt compound will be a freshly created object that gets inserted into the actual
+         * level NBT tag under the `domain:id` name.
+         * <p>
+         * If true, the nbt tag passed in into the write/read methods will be the raw Level NBT tag without filtering.
+         *
+         * @implNote This is used internally for reimplementing the vanilla logic. Only change this if you know what you're doing.
+         */
+        @Contract(pure = true)
+        default boolean chunkPrivilegedAccess() {
+            return false;
+        }
+
+        /**
+         * Serializes your data into an NBT tag. This is used when saving the chunk to disk.
+         */
+        void writeChunkToNBT(Chunk chunk, NBTTagCompound nbt);
+
+
+        /**
+         * Deserializes your data from an NBT tag. This is used when loading the chunk from disk.
+         * The NBT *may* be null if the chunk was saved before this manager was registered
+         * (e.g., loading save before the mod was added), and the manager is not {@link #chunkPrivilegedAccess() privileged}.
+         * In this case, you should initialize the data to a sane default.
+         */
+        void readChunkFromNBT(Chunk chunk, NBTTagCompound nbt);
+    }
 
     /**
-     * Deserializes your data from a packet.
-     * Mutates this object.
-     *
-     * @param chunk  The chunk to deserialize.
-     * @param buffer The packet buffer to read from.
+     * Implement this interface if you want to save your ExtendedBlockStorage data to disk. This is called once per
+     * ExtendedBlockStorage per chunk. (16 times per chunk)
      */
-    void readFromBuffer(T chunk, int ebsMask, boolean forceUpdate, ByteBuffer buffer);
+    interface SectionNBTDataManager extends ChunkDataManager {
+        /**
+         * If false, the given nbt compound will be a freshly created object that gets inserted into the actual
+         * segment NBT tag under the `domain:id` name.
+         * <p>
+         * If true, the nbt tag passed in into the write/read methods will be the raw segment NBT tag without filtering.
+         *
+         * @implNote This is used internally for reimplementing the vanilla logic. Only change this if you know what you're doing.
+         */
+        @Contract(pure = true)
+        default boolean sectionPrivilegedAccess() {
+            return false;
+        }
+        /**
+         * Serializes your data into an NBT tag. This is used when saving the chunk to disk.
+         */
+        void writeSectionToNBT(Chunk chunk, ExtendedBlockStorage ebs, NBTTagCompound section);
 
-    /**
-     * Serializes your data into an NBT tag. This is used when saving the chunk to disk.
-     * @param tag The tag to write to.
-     */
-    void writeToNBT(T chunk, @NotNull NBTTagCompound tag);
-
-    /**
-     * Deserializes your data from an NBT tag. This is used when loading the chunk from disk.
-     * Mutates this object.
-     * @param tag The tag to read from.
-     */
-    void readFromNBT(T chunk, @NotNull NBTTagCompound tag);
+        /**
+         * Deserializes your data from an NBT tag. This is used when loading the chunk from disk.
+         * The NBT *may* be null if the chunk was saved before this manager was registered
+         * (e.g., loading save before the mod was added), and the manager is not {@link #sectionPrivilegedAccess() privileged}.
+         * In this case, you should initialize the data to a sane default.
+         */
+        void readSectionFromNBT(Chunk chunk, ExtendedBlockStorage ebs, NBTTagCompound section);
+    }
 }

src/main/java/com/falsepattern/chunk/api/ChunkDataRegistry.java

@@ -13,7 +13,7 @@ public class ChunkDataRegistry {
      * @throws IllegalStateException If the registration stage is over.
      * @throws IllegalArgumentException If the manager has a duplicate id.
      */
-    public static void registerDataManager(ChunkDataManager<?> manager) throws IllegalStateException, IllegalArgumentException {
+    public static void registerDataManager(ChunkDataManager manager) throws IllegalStateException, IllegalArgumentException {
         ChunkDataRegistryImpl.registerDataManager(manager);
     }
 

src/main/java/com/falsepattern/chunk/internal/ChunkDataRegistryImpl.java

@@ -4,28 +4,35 @@ import com.falsepattern.chunk.api.ChunkDataManager;
 import lombok.val;
 import lombok.var;
 
+import net.minecraft.nbt.NBTTagCompound;
+import net.minecraft.nbt.NBTTagList;
+import net.minecraft.world.World;
 import net.minecraft.world.chunk.Chunk;
+import net.minecraft.world.chunk.storage.ExtendedBlockStorage;
 
 import java.nio.ByteBuffer;
 import java.nio.ByteOrder;
 import java.nio.charset.StandardCharsets;
 import java.util.HashMap;
 import java.util.HashSet;
+import java.util.List;
 import java.util.Map;
 import java.util.Set;
 
 public class ChunkDataRegistryImpl {
-    @SuppressWarnings("rawtypes")
-    private static final Map<String, ChunkDataManager> managers = new HashMap<>();
+    private static final Set<String> managers = new HashSet<>();
+    private static final Map<String, ChunkDataManager.PacketDataManager> packetManagers = new HashMap<>();
+    private static final Map<String, ChunkDataManager.ChunkNBTDataManager> chunkNBTManagers = new HashMap<>();
+    private static final Map<String, ChunkDataManager.SectionNBTDataManager> sectionNBTManagers = new HashMap<>();
     private static final Set<String> disabledManagers = new HashSet<>();
-    private static int maxPacketSize = 0;
-    public static void registerDataManager(ChunkDataManager<?> manager) throws IllegalStateException, IllegalArgumentException {
+    private static int maxPacketSize = 4;
+    public static void registerDataManager(ChunkDataManager manager) throws IllegalStateException, IllegalArgumentException {
         if (!ChunkAPI.isRegistrationStage()) {
             throw new IllegalStateException("ChunkDataManager registration is not allowed at this time! " +
                                                    "Please register your ChunkDataManager in the preInit phase of your mod.");
         }
         var id = manager.domain() + ":" + manager.id();
-        if (managers.containsKey(id)) {
+        if (managers.contains(id)) {
             throw new IllegalArgumentException("ChunkDataManager " + manager + " has a duplicate id!");
         }
 
@@ -34,9 +41,19 @@ public class ChunkDataRegistryImpl {
             return;
         }
 
-        managers.put(id, manager);
-        maxPacketSize += 4 + id.getBytes(StandardCharsets.UTF_8).length;
-        maxPacketSize += manager.maxPacketSize();
+        managers.add(id);
+        if (manager instanceof ChunkDataManager.PacketDataManager) {
+            val packetManager = (ChunkDataManager.PacketDataManager) manager;
+            maxPacketSize += 4 + id.getBytes(StandardCharsets.UTF_8).length;
+            maxPacketSize += packetManager.maxPacketSize();
+            packetManagers.put(id, packetManager);
+        }
+        if (manager instanceof ChunkDataManager.ChunkNBTDataManager) {
+            chunkNBTManagers.put(id, (ChunkDataManager.ChunkNBTDataManager) manager);
+        }
+        if (manager instanceof ChunkDataManager.SectionNBTDataManager) {
+            sectionNBTManagers.put(id, (ChunkDataManager.SectionNBTDataManager) manager);
+        }
     }
 
     public static void disableDataManager(String domain, String id) {
@@ -44,17 +61,22 @@ public class ChunkDataRegistryImpl {
             throw new IllegalStateException("ChunkDataManager disabling is not allowed at this time! " +
                                             "Please disable any ChunkDataManagers in the preInit/init phases.");
         }
-        id = domain + ":" + id;
-        Common.LOG.warn("Disabling ChunkDataManager " + id + ". See the stacktrace for the source of this event.", new Throwable());
+        Common.LOG.warn("Disabling ChunkDataManager " + id + " in domain " + domain + ". See the stacktrace for the source of this event.", new Throwable());
+        val manager = domain + ":" + id;
         //Remove the manager from the list of managers, if it exists
-        val removed = managers.remove(id);
-        if (removed != null) {
-            maxPacketSize -= 4 + id.getBytes(StandardCharsets.UTF_8).length;
-            maxPacketSize -= removed.maxPacketSize();
+        if (managers.remove(manager)) {
+            //Clear the maps
+            if (packetManagers.containsKey(id)) {
+                val removed = packetManagers.remove(id);
+                maxPacketSize -= 4 + id.getBytes(StandardCharsets.UTF_8).length;
+                maxPacketSize -= removed.maxPacketSize();
+            }
+            chunkNBTManagers.remove(id);
+            sectionNBTManagers.remove(id);
         }
 
         //Add the manager to the list of disabled managers, in case it gets registered after this disable call.
-        disabledManagers.add(id);
+        disabledManagers.add(manager);
     }
 
     public static int maxPacketSize() {
@@ -74,7 +96,6 @@ public class ChunkDataRegistryImpl {
         return new String(bytes);
     }
 
-    @SuppressWarnings("unchecked")
     public static void readFromBuffer(Chunk chunk, int ebsMask, boolean forceUpdate, byte[] data) {
         val buf = ByteBuffer.wrap(data);
         buf.order(ByteOrder.LITTLE_ENDIAN);
@@ -82,9 +103,9 @@ public class ChunkDataRegistryImpl {
         for (int i = 0; i < count; i++) {
             val id = readString(buf);
             val length = buf.getInt();
-            val manager = managers.get(id);
+            val manager = packetManagers.get(id);
             if (manager == null) {
-                Common.LOG.error("Received data for unknown ChunkDataManager " + id + ". Skipping.");
+                Common.LOG.error("Received data for unknown PacketDataManager " + id + ". Skipping.");
                 buf.position(buf.position() + length);
                 continue;
             }
@@ -95,14 +116,14 @@ public class ChunkDataRegistryImpl {
         }
     }
 
-    @SuppressWarnings("unchecked")
     public static int writeToBuffer(Chunk chunk, int ebsMask, boolean forceUpdate, byte[] data) {
         val buf = ByteBuffer.wrap(data);
         buf.order(ByteOrder.LITTLE_ENDIAN);
-        buf.putInt(managers.size());
-        for (val pair: managers.entrySet()) {
+        buf.putInt(packetManagers.size());
+        for (val pair: packetManagers.entrySet()) {
+            val id = pair.getKey();
             val manager = pair.getValue();
-            writeString(buf, pair.getKey());
+            writeString(buf, id);
             int start = buf.position() + 4;
             val slice = createSlice(buf, start, manager.maxPacketSize());
             manager.writeToBuffer(chunk, ebsMask, forceUpdate, slice);
@@ -123,4 +144,60 @@ public class ChunkDataRegistryImpl {
         buffer.position(oldPosition);
         return slice;
     }
+
+    private static NBTTagCompound createManagerNBT(boolean privileged, NBTTagCompound root, ChunkDataManager manager) {
+        if (privileged) {
+            return root;
+        }
+        val domain = manager.domain();
+        NBTTagCompound domainNBT;
+        if (root.hasKey(domain)) {
+            domainNBT = new NBTTagCompound();
+            root.setTag(domain, domainNBT);
+        } else {
+            domainNBT = root.getCompoundTag(domain);
+        }
+        val subNBT = new NBTTagCompound();
+        domainNBT.setTag(manager.id(), subNBT);
+        return subNBT;
+    }
+
+    private static NBTTagCompound getManagerNBT(boolean privileged, NBTTagCompound root, ChunkDataManager manager) {
+        if (privileged) {
+            return root;
+        }
+        val domain = manager.domain();
+        if (!root.hasKey(domain)) {
+            return null;
+        }
+        val domainNBT = root.getCompoundTag(domain);
+        if (!domainNBT.hasKey(manager.id())) {
+            return null;
+        }
+        return domainNBT.getCompoundTag(manager.id());
+    }
+
+    public static void writeSectionToNBT(Chunk chunk, ExtendedBlockStorage ebs, NBTTagCompound sectionNBT) {
+        for (val manager: sectionNBTManagers.values()) {
+            manager.writeSectionToNBT(chunk, ebs, createManagerNBT(manager.sectionPrivilegedAccess(), sectionNBT, manager));
+        }
+    }
+
+    public static void readSectionFromNBT(Chunk chunk, ExtendedBlockStorage ebs, NBTTagCompound sectionNBT) {
+        for (val manager: sectionNBTManagers.values()) {
+            manager.readSectionFromNBT(chunk, ebs, getManagerNBT(manager.sectionPrivilegedAccess(), sectionNBT, manager));
+        }
+    }
+
+    public static void writeChunkToNBT(Chunk chunk, NBTTagCompound chunkNBT) {
+        for (val manager: chunkNBTManagers.values()) {
+            manager.writeChunkToNBT(chunk, createManagerNBT(manager.chunkPrivilegedAccess(), chunkNBT, manager));
+        }
+    }
+
+    public static void readChunkFromNBT(Chunk chunk, NBTTagCompound chunkNBT) {
+        for (val manager: chunkNBTManagers.values()) {
+            manager.readChunkFromNBT(chunk, getManagerNBT(manager.chunkPrivilegedAccess(), chunkNBT, manager));
+        }
+    }
 }

src/main/java/com/falsepattern/chunk/internal/mixin/mixins/common/vanilla/AnvilChunkLoaderMixin.java

@@ -0,0 +1,174 @@
+package com.falsepattern.chunk.internal.mixin.mixins.common.vanilla;
+
+import com.falsepattern.chunk.internal.ChunkDataRegistryImpl;
+import lombok.val;
+import org.apache.logging.log4j.Level;
+import org.spongepowered.asm.mixin.Mixin;
+import org.spongepowered.asm.mixin.Overwrite;
+
+import net.minecraft.block.Block;
+import net.minecraft.entity.Entity;
+import net.minecraft.nbt.NBTTagCompound;
+import net.minecraft.nbt.NBTTagList;
+import net.minecraft.tileentity.TileEntity;
+import net.minecraft.world.NextTickListEntry;
+import net.minecraft.world.World;
+import net.minecraft.world.chunk.Chunk;
+import net.minecraft.world.chunk.NibbleArray;
+import net.minecraft.world.chunk.storage.AnvilChunkLoader;
+import net.minecraft.world.chunk.storage.ExtendedBlockStorage;
+import cpw.mods.fml.common.FMLLog;
+
+import java.util.List;
+
+@Mixin(AnvilChunkLoader.class)
+public abstract class AnvilChunkLoaderMixin {
+    /**
+     * Writes the Chunk passed as an argument to the NBTTagCompound also passed, using the World argument to retrieve
+     * the Chunk's last update time.
+     * @author FalsePattern
+     * @reason Replace functionality
+     */
+    @Overwrite
+    private void writeChunkToNBT(Chunk chunk, World world, NBTTagCompound nbt) {
+        nbt.setByte("V", (byte)1);
+        nbt.setInteger("xPos", chunk.xPosition);
+        nbt.setInteger("zPos", chunk.zPosition);
+        System.out.println("Saving chunk " + chunk.xPosition + ", " + chunk.zPosition);
+        nbt.setLong("LastUpdate", world.getTotalWorldTime());
+        nbt.setIntArray("HeightMap", chunk.heightMap);
+        nbt.setBoolean("TerrainPopulated", chunk.isTerrainPopulated);
+        nbt.setBoolean("LightPopulated", chunk.isLightPopulated);
+        nbt.setLong("InhabitedTime", chunk.inhabitedTime);
+        writeSections(chunk, nbt);
+        writeCustomData(chunk, nbt);
+        writeEntities(chunk, world, nbt);
+    }
+
+    /**
+     * Reads the data stored in the given NBTTagCompound and creates a Chunk with that data in the given World.
+     * Returns the created Chunk.
+     * @author FalsePattern
+     * @reason Replace functionality
+     */
+    @Overwrite
+    private Chunk readChunkFromNBT(World world, NBTTagCompound nbt) {
+        int x = nbt.getInteger("xPos");
+        int z = nbt.getInteger("zPos");
+        System.out.println("Loading chunk " + x + ", " + z );
+        Chunk chunk = new Chunk(world, x, z);
+        chunk.heightMap = nbt.getIntArray("HeightMap");
+        chunk.isTerrainPopulated = nbt.getBoolean("TerrainPopulated");
+        chunk.isLightPopulated = nbt.getBoolean("LightPopulated");
+        chunk.inhabitedTime = nbt.getLong("InhabitedTime");
+        readSections(chunk, nbt);
+        readCustomData(chunk, nbt);
+
+        // End this method here and split off entity loading to another method
+        return chunk;
+    }
+
+    private void readCustomData(Chunk chunk, NBTTagCompound nbt) {
+        ChunkDataRegistryImpl.readChunkFromNBT(chunk, nbt);
+    }
+
+    private void readSections(Chunk chunk, NBTTagCompound nbt) {
+        NBTTagList sections = nbt.getTagList("Sections", 10);
+        byte segments = 16;
+        ExtendedBlockStorage[] ebsList = new ExtendedBlockStorage[segments];
+
+        for (int k = 0; k < sections.tagCount(); ++k) {
+            NBTTagCompound section = sections.getCompoundTagAt(k);
+            byte yLevel = section.getByte("Y");
+            ExtendedBlockStorage ebs = new ExtendedBlockStorage(yLevel << 4, !chunk.worldObj.provider.hasNoSky);
+            ChunkDataRegistryImpl.readSectionFromNBT(chunk, ebs, section);
+
+            ebs.removeInvalidBlocks();
+            ebsList[yLevel] = ebs;
+        }
+
+        chunk.setStorageArrays(ebsList);
+    }
+
+    private void writeCustomData(Chunk chunk, NBTTagCompound nbt) {
+        ChunkDataRegistryImpl.writeChunkToNBT(chunk, nbt);
+    }
+
+    private void writeSections(Chunk chunk, NBTTagCompound nbt) {
+        ExtendedBlockStorage[] ebsList = chunk.getBlockStorageArray();
+        NBTTagList sections = new NBTTagList();
+        NBTTagCompound section;
+
+        for (ExtendedBlockStorage ebs: ebsList) {
+            if (ebs != null) {
+                section = new NBTTagCompound();
+                section.setByte("Y", (byte) (ebs.getYLocation() >> 4 & 255));
+                ChunkDataRegistryImpl.writeSectionToNBT(chunk, ebs, section);
+                sections.appendTag(section);
+            }
+        }
+
+        nbt.setTag("Sections", sections);
+    }
+
+    private void writeEntities(Chunk chunk, World world, NBTTagCompound nbt) {
+        chunk.hasEntities = false;
+        NBTTagList entities = new NBTTagList();
+
+        for (int i = 0; i < chunk.entityLists.length; ++i) {
+            for (Object o: chunk.entityLists[i]) {
+                Entity entity = (Entity) o;
+                val entityNBT = new NBTTagCompound();
+
+                try {
+                    if (entity.writeToNBTOptional(entityNBT)) {
+                        chunk.hasEntities = true;
+                        entities.appendTag(entityNBT);
+                    }
+                } catch (Exception e) {
+                    FMLLog.log(Level.ERROR, e,
+                               "An Entity type %s has thrown an exception trying to write state. It will not persist. Report this to the mod author",
+                               entity.getClass().getName());
+                }
+            }
+        }
+
+        nbt.setTag("Entities", entities);
+        NBTTagList tileEntities = new NBTTagList();
+
+        for (Object o: chunk.chunkTileEntityMap.values()) {
+            TileEntity tileentity = (TileEntity) o;
+            val tileEntityNBT = new NBTTagCompound();
+            try {
+                tileentity.writeToNBT(tileEntityNBT);
+                tileEntities.appendTag(tileEntityNBT);
+            } catch (Exception e) {
+                FMLLog.log(Level.ERROR, e,
+                           "A TileEntity type %s has throw an exception trying to write state. It will not persist. Report this to the mod author",
+                           tileentity.getClass().getName());
+            }
+        }
+
+        nbt.setTag("TileEntities", tileEntities);
+        List<?> pendingUpdates = world.getPendingBlockUpdates(chunk, false);
+
+        if (pendingUpdates != null) {
+            long k = world.getTotalWorldTime();
+            NBTTagList tileTicks = new NBTTagList();
+
+            for (Object o : pendingUpdates) {
+                NextTickListEntry update = (NextTickListEntry) o;
+                NBTTagCompound updateNBT = new NBTTagCompound();
+                updateNBT.setInteger("i", Block.getIdFromBlock(update.func_151351_a()));
+                updateNBT.setInteger("x", update.xCoord);
+                updateNBT.setInteger("y", update.yCoord);
+                updateNBT.setInteger("z", update.zCoord);
+                updateNBT.setInteger("t", (int) (update.scheduledTime - k));
+                updateNBT.setInteger("p", update.priority);
+                tileTicks.appendTag(updateNBT);
+            }
+
+            nbt.setTag("TileTicks", tileTicks);
+        }
+    }
+}

src/main/java/com/falsepattern/chunk/internal/mixin/mixins/common/vanilla/S21PacketChunkDataMixin.java

@@ -53,7 +53,6 @@ public abstract class S21PacketChunkDataMixin {
         if (buffer.length < ChunkDataRegistryImpl.maxPacketSize()) {
             buffer = new byte[ChunkDataRegistryImpl.maxPacketSize()];
         }
-        val data = buffer;
 
         if (forceUpdate) {
             chunk.sendUpdates = true;
@@ -65,10 +64,10 @@ public abstract class S21PacketChunkDataMixin {
             }
         }
 
-        int length = ChunkDataRegistryImpl.writeToBuffer(chunk, extracted.field_150280_b, forceUpdate, data);
+        int length = ChunkDataRegistryImpl.writeToBuffer(chunk, extracted.field_150280_b, forceUpdate, buffer);
 
         extracted.field_150282_a = new byte[length];
-        System.arraycopy(data, 0, extracted.field_150282_a, 0, length);
+        System.arraycopy(buffer, 0, extracted.field_150282_a, 0, length);
         return extracted;
     }
 
@@ -90,6 +89,7 @@ public abstract class S21PacketChunkDataMixin {
         }
         data.writeInt(xPosition);
         data.writeInt(zPosition);
+        System.out.println("Writing chunk packet (" + xPosition + ", " + zPosition + ")");
         data.writeBoolean(forceUpdate);
         data.writeShort((short)(ebsMask & 0xFFFF));
         data.writeInt(this.data.length);
@@ -105,6 +105,7 @@ public abstract class S21PacketChunkDataMixin {
     public void readPacketData(PacketBuffer data) throws IOException {
         xPosition = data.readInt();
         zPosition = data.readInt();
+        System.out.println("Reading chunk packet (" + xPosition + ", " + zPosition + ")");
         forceUpdate = data.readBoolean();
         ebsMask = data.readShort() & 0xFFFF;
         this.data = new byte[data.readInt()];

src/main/java/com/falsepattern/chunk/internal/mixin/plugin/Mixin.java

@@ -36,6 +36,7 @@ import static com.falsepattern.lib.mixin.IMixin.PredicateHelpers.always;
 @RequiredArgsConstructor
 public enum Mixin implements IMixin {
     // @formatter:off
+    AnvilChunkLoaderMixin(Side.COMMON, always(), "vanilla.AnvilChunkLoaderMixin"),
     S21PacketChunkDataMixin(Side.COMMON, always(), "vanilla.S21PacketChunkDataMixin"),
     S26PacketMapChunkBulkMixin(Side.COMMON, always(), "vanilla.S26PacketMapChunkBulkMixin"),
 

src/main/java/com/falsepattern/chunk/internal/vanilla/BiomeManager.java

@@ -1,13 +1,16 @@
 package com.falsepattern.chunk.internal.vanilla;
 
+import com.falsepattern.chunk.api.ChunkDataManager;
 import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
 
 import net.minecraft.nbt.NBTTagCompound;
+import net.minecraft.world.World;
 import net.minecraft.world.chunk.Chunk;
 
 import java.nio.ByteBuffer;
 
-public class BiomeManager extends VanillaManager {
+public class BiomeManager extends VanillaManager implements ChunkDataManager.PacketDataManager, ChunkDataManager.ChunkNBTDataManager {
     public static final int BYTES_PER_CHUNK = 256;
 
     @Override
@@ -21,26 +24,34 @@ public class BiomeManager extends VanillaManager {
     }
 
     @Override
-    public void writeToBuffer(Chunk chunk, int ebsMask, boolean forceUpdate, ByteBuffer data) {
+    public void writeToBuffer(@NotNull Chunk chunk, int ebsMask, boolean forceUpdate, @NotNull ByteBuffer data) {
         if (forceUpdate) {
             data.put(chunk.getBiomeArray());
         }
     }
 
     @Override
-    public void readFromBuffer(Chunk chunk, int ebsMask, boolean forceUpdate, ByteBuffer buffer) {
+    public void readFromBuffer(@NotNull Chunk chunk, int ebsMask, boolean forceUpdate, @NotNull ByteBuffer buffer) {
         if (forceUpdate) {
             buffer.get(chunk.getBiomeArray());
         }
     }
 
     @Override
-    public void writeToNBT(Chunk chunk, @NotNull NBTTagCompound tag) {
+    public boolean chunkPrivilegedAccess() {
+        return true;
+    }
 
+
+    @Override
+    public void writeChunkToNBT(@NotNull Chunk chunk, @NotNull NBTTagCompound nbt) {
+        nbt.setByteArray("Biomes", chunk.getBiomeArray());
     }
 
     @Override
-    public void readFromNBT(Chunk chunk, @NotNull NBTTagCompound tag) {
-
+    public void readChunkFromNBT(@NotNull Chunk chunk, @NotNull NBTTagCompound nbt) {
+        if (nbt.hasKey("Biomes", 7)) {
+            chunk.setBiomeArray(nbt.getByteArray("Biomes"));
+        }
     }
 }

src/main/java/com/falsepattern/chunk/internal/vanilla/BlockIDManager.java

@@ -1,17 +1,21 @@
 package com.falsepattern.chunk.internal.vanilla;
 
+import com.falsepattern.chunk.api.ChunkDataManager;
 import lombok.val;
 import org.jetbrains.annotations.NotNull;
 
 import net.minecraft.nbt.NBTTagCompound;
+import net.minecraft.world.World;
 import net.minecraft.world.chunk.Chunk;
+import net.minecraft.world.chunk.NibbleArray;
+import net.minecraft.world.chunk.storage.ExtendedBlockStorage;
 
 import java.nio.ByteBuffer;
 
 import static com.falsepattern.chunk.internal.Common.BLOCKS_PER_EBS;
 import static com.falsepattern.chunk.internal.Common.EBS_PER_CHUNK;
 
-public class BlockIDManager extends VanillaManager {
+public class BlockIDManager extends VanillaManager implements ChunkDataManager.PacketDataManager, ChunkDataManager.SectionNBTDataManager {
     private static final int LSB_BYTES_PER_EBS = BLOCKS_PER_EBS;
     private static final int MSB_BYTES_PER_EBS = BLOCKS_PER_EBS / 2;
     private static final int HEADER_SIZE = 2;
@@ -72,12 +76,25 @@ public class BlockIDManager extends VanillaManager {
     }
 
     @Override
-    public void writeToNBT(Chunk chunk, @NotNull NBTTagCompound tag) {
-
+    public boolean sectionPrivilegedAccess() {
+        return true;
     }
 
     @Override
-    public void readFromNBT(Chunk chunk, @NotNull NBTTagCompound tag) {
+    public void writeSectionToNBT(Chunk chunk, ExtendedBlockStorage ebs, NBTTagCompound section) {
+        section.setByteArray("Blocks", ebs.getBlockLSBArray());
 
+        if (ebs.getBlockMSBArray() != null) {
+            section.setByteArray("Add", ebs.getBlockMSBArray().data);
+        }
+    }
+
+    @Override
+    public void readSectionFromNBT(Chunk chunk, ExtendedBlockStorage ebs, NBTTagCompound section) {
+        ebs.setBlockLSBArray(section.getByteArray("Blocks"));
+
+        if (section.hasKey("Add", 7)) {
+            ebs.setBlockMSBArray(new NibbleArray(section.getByteArray("Add"), 4));
+        }
     }
 }

src/main/java/com/falsepattern/chunk/internal/vanilla/BlocklightManager.java

@@ -1,9 +1,13 @@
 package com.falsepattern.chunk.internal.vanilla;
 
+import com.falsepattern.chunk.api.ChunkDataManager;
+
+import net.minecraft.nbt.NBTTagCompound;
+import net.minecraft.world.chunk.Chunk;
 import net.minecraft.world.chunk.NibbleArray;
 import net.minecraft.world.chunk.storage.ExtendedBlockStorage;
 
-public class BlocklightManager extends NibbleManager {
+public class BlocklightManager extends NibbleManager implements ChunkDataManager.SectionNBTDataManager {
     @Override
     protected NibbleArray getNibbleArray(ExtendedBlockStorage ebs) {
         return ebs.getBlocklightArray();
@@ -13,4 +17,19 @@ public class BlocklightManager extends NibbleManager {
     public String id() {
         return "blocklight";
     }
+
+    @Override
+    public boolean sectionPrivilegedAccess() {
+        return true;
+    }
+
+    @Override
+    public void writeSectionToNBT(Chunk chunk, ExtendedBlockStorage ebs, NBTTagCompound section) {
+        section.setByteArray("BlockLight", ebs.getBlocklightArray().data);
+    }
+
+    @Override
+    public void readSectionFromNBT(Chunk chunk, ExtendedBlockStorage ebs, NBTTagCompound section) {
+        ebs.setBlocklightArray(new NibbleArray(section.getByteArray("BlockLight"), 4));
+    }
 }

src/main/java/com/falsepattern/chunk/internal/vanilla/MetadataManager.java

@@ -1,9 +1,13 @@
 package com.falsepattern.chunk.internal.vanilla;
 
+import com.falsepattern.chunk.api.ChunkDataManager;
+
+import net.minecraft.nbt.NBTTagCompound;
+import net.minecraft.world.chunk.Chunk;
 import net.minecraft.world.chunk.NibbleArray;
 import net.minecraft.world.chunk.storage.ExtendedBlockStorage;
 
-public class MetadataManager extends NibbleManager {
+public class MetadataManager extends NibbleManager implements ChunkDataManager.SectionNBTDataManager {
     @Override
     protected NibbleArray getNibbleArray(ExtendedBlockStorage ebs) {
         return ebs.getMetadataArray();
@@ -13,4 +17,19 @@ public class MetadataManager extends NibbleManager {
     public String id() {
         return "metadata";
     }
+
+    @Override
+    public boolean sectionPrivilegedAccess() {
+        return true;
+    }
+
+    @Override
+    public void writeSectionToNBT(Chunk chunk, ExtendedBlockStorage ebs, NBTTagCompound section) {
+        section.setByteArray("Data", ebs.getMetadataArray().data);
+    }
+
+    @Override
+    public void readSectionFromNBT(Chunk chunk, ExtendedBlockStorage ebs, NBTTagCompound section) {
+        ebs.setBlockMetadataArray(new NibbleArray(section.getByteArray("Data"), 4));
+    }
 }

src/main/java/com/falsepattern/chunk/internal/vanilla/NibbleManager.java

@@ -1,17 +1,16 @@
 package com.falsepattern.chunk.internal.vanilla;
 
+import com.falsepattern.chunk.api.ChunkDataManager;
 import com.falsepattern.chunk.internal.Common;
 import lombok.val;
-import org.jetbrains.annotations.NotNull;
 
-import net.minecraft.nbt.NBTTagCompound;
 import net.minecraft.world.chunk.Chunk;
 import net.minecraft.world.chunk.NibbleArray;
 import net.minecraft.world.chunk.storage.ExtendedBlockStorage;
 
 import java.nio.ByteBuffer;
 
-public abstract class NibbleManager extends VanillaManager {
+public abstract class NibbleManager extends VanillaManager implements ChunkDataManager.PacketDataManager {
     public static final int BYTES_PER_EBS = Common.BLOCKS_PER_EBS / 2;
 
     protected abstract NibbleArray getNibbleArray(ExtendedBlockStorage ebs);
@@ -46,14 +45,4 @@ public abstract class NibbleManager extends VanillaManager {
             }
         }
     }
-
-    @Override
-    public void writeToNBT(Chunk chunk, @NotNull NBTTagCompound tag) {
-
-    }
-
-    @Override
-    public void readFromNBT(Chunk chunk, @NotNull NBTTagCompound tag) {
-
-    }
 }

src/main/java/com/falsepattern/chunk/internal/vanilla/SkylightManager.java

@@ -1,12 +1,15 @@
 package com.falsepattern.chunk.internal.vanilla;
 
+import com.falsepattern.chunk.api.ChunkDataManager;
+
+import net.minecraft.nbt.NBTTagCompound;
 import net.minecraft.world.chunk.Chunk;
 import net.minecraft.world.chunk.NibbleArray;
 import net.minecraft.world.chunk.storage.ExtendedBlockStorage;
 
 import java.nio.ByteBuffer;
 
-public class SkylightManager extends NibbleManager {
+public class SkylightManager extends NibbleManager implements ChunkDataManager.SectionNBTDataManager {
     @Override
     public String id() {
         return "skylight";
@@ -30,4 +33,25 @@ public class SkylightManager extends NibbleManager {
             super.readFromBuffer(chunk, ebsMask, forceUpdate, buffer);
         }
     }
+
+    @Override
+    public boolean sectionPrivilegedAccess() {
+        return true;
+    }
+
+    @Override
+    public void writeSectionToNBT(Chunk chunk, ExtendedBlockStorage ebs, NBTTagCompound section) {
+        if (!chunk.worldObj.provider.hasNoSky) {
+            section.setByteArray("SkyLight", ebs.getSkylightArray().data);
+        } else {
+            section.setByteArray("SkyLight", new byte[ebs.getBlocklightArray().data.length]);
+        }
+    }
+
+    @Override
+    public void readSectionFromNBT(Chunk chunk, ExtendedBlockStorage ebs, NBTTagCompound section) {
+        if (!chunk.worldObj.provider.hasNoSky) {
+            ebs.setSkylightArray(new NibbleArray(section.getByteArray("SkyLight"), 4));
+        }
+    }
 }

src/main/java/com/falsepattern/chunk/internal/vanilla/VanillaManager.java

@@ -2,16 +2,9 @@ package com.falsepattern.chunk.internal.vanilla;
 
 import com.falsepattern.chunk.api.ChunkDataManager;
 
-import net.minecraft.world.chunk.Chunk;
-
-public abstract class VanillaManager implements ChunkDataManager<Chunk> {
+public abstract class VanillaManager implements ChunkDataManager {
     @Override
     public String domain() {
         return "minecraft";
     }
-
-    @Override
-    public void init(Chunk chunk) {
-
-    }
 }