Initial anvil support

src/main/java/net/minestom/server/instance/AnvilLoader.java

@@ -0,0 +1,140 @@
+package net.minestom.server.instance;
+
+import net.minestom.server.MinecraftServer;
+import net.minestom.server.instance.block.Block;
+import net.minestom.server.utils.chunk.ChunkCallback;
+import net.minestom.server.world.biomes.Biome;
+import net.minestom.server.world.biomes.BiomeManager;
+import org.jglrxavpok.hephaistos.mca.*;
+import org.jglrxavpok.hephaistos.nbt.NBTCompound;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import java.io.IOException;
+import java.io.RandomAccessFile;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.util.Arrays;
+import java.util.Map;
+import java.util.Objects;
+import java.util.concurrent.ConcurrentHashMap;
+
+public class AnvilLoader implements IChunkLoader {
+    private final static Logger LOGGER = LoggerFactory.getLogger(AnvilLoader.class);
+    private static final BiomeManager BIOME_MANAGER = MinecraftServer.getBiomeManager();
+    private static final Biome BIOME = Biome.PLAINS;
+
+    private final Map<String, RegionFile> alreadyLoaded = new ConcurrentHashMap<>();
+    private final Path path;
+
+    public AnvilLoader(Path path) {
+        this.path = path;
+    }
+
+    public AnvilLoader(String path) {
+        this(Path.of(path));
+    }
+
+    @Override
+    public boolean loadChunk(Instance instance, int chunkX, int chunkZ, ChunkCallback callback) {
+        LOGGER.debug("Attempt loading at {} {}", chunkX, chunkZ);
+        try {
+            Chunk chunk = loadMCA(instance, chunkX, chunkZ, callback);
+            return chunk != null;
+        } catch (IOException | AnvilException e) {
+            e.printStackTrace();
+        }
+        return false;
+    }
+
+    private Chunk loadMCA(Instance instance, int chunkX, int chunkZ, ChunkCallback callback) throws IOException, AnvilException {
+        RegionFile mcaFile = getMCAFile(chunkX, chunkZ);
+        if (mcaFile != null) {
+            ChunkColumn fileChunk = mcaFile.getChunk(chunkX, chunkZ);
+            if (fileChunk != null) {
+                Biome[] biomes;
+                if (fileChunk.getGenerationStatus().compareTo(ChunkColumn.GenerationStatus.Biomes) > 0) {
+                    int[] fileChunkBiomes = fileChunk.getBiomes();
+                    biomes = new Biome[fileChunkBiomes.length];
+                    for (int i = 0; i < fileChunkBiomes.length; i++) {
+                        final int id = fileChunkBiomes[i];
+                        biomes[i] = Objects.requireNonNullElse(BIOME_MANAGER.getById(id), BIOME);
+                    }
+                } else {
+                    biomes = new Biome[1024]; // TODO don't hardcode
+                    Arrays.fill(biomes, BIOME);
+                }
+                Chunk chunk = new DynamicChunk(instance, biomes, chunkX, chunkZ);
+                placeBlocks(chunk, fileChunk);
+                loadTileEntities(chunk, fileChunk);
+                if (callback != null) {
+                    callback.accept(chunk);
+                }
+                return chunk;
+            }
+        }
+        return null;
+    }
+
+    private RegionFile getMCAFile(int chunkX, int chunkZ) {
+        int regionX = CoordinatesKt.chunkToRegion(chunkX);
+        int regionZ = CoordinatesKt.chunkToRegion(chunkZ);
+        return alreadyLoaded.computeIfAbsent(RegionFile.Companion.createFileName(regionX, regionZ), n -> {
+            try {
+                final Path regionPath = path.resolve("region").resolve(n);
+                if (!Files.exists(regionPath)) {
+                    return null;
+                }
+                return new RegionFile(new RandomAccessFile(regionPath.toFile(), "rw"), regionX, regionZ);
+            } catch (IOException | AnvilException e) {
+                e.printStackTrace();
+                return null;
+            }
+        });
+    }
+
+    private void loadTileEntities(Chunk loadedChunk, ChunkColumn fileChunk) {
+        for (NBTCompound te : fileChunk.getTileEntities()) {
+            final String tileEntityID = te.getString("id");
+            final int x = te.getInt("x") + loadedChunk.getChunkX() * 16;
+            final int y = te.getInt("y");
+            final int z = te.getInt("z") + loadedChunk.getChunkZ() * 16;
+            if (tileEntityID != null) {
+                // TODO load BlockHandler and place
+            }
+        }
+    }
+
+    private void placeBlocks(Chunk chunk, ChunkColumn fileChunk) {
+        for (int x = 0; x < Chunk.CHUNK_SIZE_X; x++) {
+            for (int z = 0; z < Chunk.CHUNK_SIZE_Z; z++) {
+                for (int y = 0; y < 256; y++) { // TODO don't hardcode height
+                    try {
+                        // TODO: are there block entities here?
+                        final BlockState blockState = fileChunk.getBlockState(x, y, z);
+                        Block block = Block.fromNamespaceId(blockState.getName());
+                        if (block == null) {
+                            // Invalid block
+                            continue;
+                        }
+                        final var properties = blockState.getProperties();
+                        if (!properties.isEmpty()) {
+                            block = block.withProperties(properties);
+                        }
+                        chunk.setBlock(x, y, z, block);
+                    } catch (Exception e) {
+                        e.printStackTrace();
+                    }
+                }
+            }
+        }
+    }
+
+    // TODO: find a way to unload MCAFiles when an entire region is unloaded
+
+    @Override
+    public void saveChunk(Chunk chunk, Runnable callback) {
+        // TODO
+        callback.run();
+    }
+}

src/main/java/net/minestom/server/instance/InstanceContainer.java

@@ -89,8 +89,8 @@ public class InstanceContainer extends Instance {
         // Set the default chunk supplier using DynamicChunk
         setChunkSupplier(DynamicChunk::new);
 
-        // Set the default chunk loader which use the instance's StorageLocation and ChunkSupplier to save and load chunks
+        // Set the default chunk loader which use the Anvil format
-        setChunkLoader(new MinestomBasicChunkLoader(this));
+        setChunkLoader(new AnvilLoader("world"));
 
         // Get instance data from the saved data if a StorageLocation is defined
         if (storageLocation != null) {

src/main/java/net/minestom/server/instance/block/Block.java

@@ -31,6 +31,15 @@ public interface Block extends ProtocolObject, TagReadable, BlockConstants {
         return withProperty(property.getName(), value.toString());
     }
 
+    @Contract(pure = true)
+    default @NotNull Block withProperties(@NotNull Map<@NotNull String, @NotNull String> properties) {
+        Block block = this;
+        for (var entry : properties.entrySet()) {
+            block = block.withProperty(entry.getKey(), entry.getValue());
+        }
+        return block;
+    }
+
     @Contract(pure = true)
     @NotNull Block withNbt(@Nullable NBTCompound compound);