minecraft-src/net/minecraft/data/structures/SnbtToNbt.java

package net.minecraft.data.structures;

import com.google.common.collect.Lists;
import com.google.common.hash.HashCode;
import com.google.common.hash.Hashing;
import com.google.common.hash.HashingOutputStream;
import com.mojang.logging.LogUtils;
import java.io.BufferedReader;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.nio.file.Files;
import java.nio.file.Path;
import java.util.List;
import java.util.concurrent.CompletableFuture;
import java.util.stream.Stream;
import net.minecraft.Util;
import net.minecraft.data.CachedOutput;
import net.minecraft.data.DataProvider;
import net.minecraft.data.PackOutput;
import net.minecraft.nbt.CompoundTag;
import net.minecraft.nbt.NbtIo;
import net.minecraft.nbt.NbtUtils;
import org.apache.commons.io.IOUtils;
import org.slf4j.Logger;

public class SnbtToNbt implements DataProvider {
	private static final Logger LOGGER = LogUtils.getLogger();
	private final PackOutput output;
	private final Iterable<Path> inputFolders;
	private final List<SnbtToNbt.Filter> filters = Lists.<SnbtToNbt.Filter>newArrayList();

	public SnbtToNbt(PackOutput output, Iterable<Path> inputFolders) {
		this.output = output;
		this.inputFolders = inputFolders;
	}

	public SnbtToNbt addFilter(SnbtToNbt.Filter filter) {
		this.filters.add(filter);
		return this;
	}

	private CompoundTag applyFilters(String fileName, CompoundTag tag) {
		CompoundTag compoundTag = tag;

		for (SnbtToNbt.Filter filter : this.filters) {
			compoundTag = filter.apply(fileName, compoundTag);
		}

		return compoundTag;
	}

	@Override
	public CompletableFuture<?> run(CachedOutput output) {
		Path path = this.output.getOutputFolder();
		List<CompletableFuture<?>> list = Lists.<CompletableFuture<?>>newArrayList();

		for (Path path2 : this.inputFolders) {
			list.add(
				CompletableFuture.supplyAsync(
						() -> {
							try {
								Stream<Path> stream = Files.walk(path2);

								CompletableFuture var5x;
								try {
									var5x = CompletableFuture.allOf(
										(CompletableFuture[])stream.filter(pathxx -> pathxx.toString().endsWith(".snbt")).map(path3 -> CompletableFuture.runAsync(() -> {
											SnbtToNbt.TaskResult taskResult = this.readStructure(path3, this.getName(path2, path3));
											this.storeStructureIfChanged(output, taskResult, path);
										}, Util.backgroundExecutor())).toArray(CompletableFuture[]::new)
									);
								} catch (Throwable var8) {
									if (stream != null) {
										try {
											stream.close();
										} catch (Throwable var7) {
											var8.addSuppressed(var7);
										}
									}

									throw var8;
								}

								if (stream != null) {
									stream.close();
								}

								return var5x;
							} catch (Exception var9) {
								throw new RuntimeException("Failed to read structure input directory, aborting", var9);
							}
						},
						Util.backgroundExecutor()
					)
					.thenCompose(completableFuture -> completableFuture)
			);
		}

		return Util.sequenceFailFast(list);
	}

	@Override
	public final String getName() {
		return "SNBT -> NBT";
	}

	/**
	 * Gets the name of the given SNBT file, based on its path and the input directory. The result does not have the ".snbt" extension.
	 */
	private String getName(Path inputFolder, Path file) {
		String string = inputFolder.relativize(file).toString().replaceAll("\\\\", "/");
		return string.substring(0, string.length() - ".snbt".length());
	}

	private SnbtToNbt.TaskResult readStructure(Path filePath, String fileName) {
		try {
			BufferedReader bufferedReader = Files.newBufferedReader(filePath);

			SnbtToNbt.TaskResult var10;
			try {
				String string = IOUtils.toString(bufferedReader);
				CompoundTag compoundTag = this.applyFilters(fileName, NbtUtils.snbtToStructure(string));
				ByteArrayOutputStream byteArrayOutputStream = new ByteArrayOutputStream();
				HashingOutputStream hashingOutputStream = new HashingOutputStream(Hashing.sha1(), byteArrayOutputStream);
				NbtIo.writeCompressed(compoundTag, hashingOutputStream);
				byte[] bs = byteArrayOutputStream.toByteArray();
				HashCode hashCode = hashingOutputStream.hash();
				var10 = new SnbtToNbt.TaskResult(fileName, bs, hashCode);
			} catch (Throwable var12) {
				if (bufferedReader != null) {
					try {
						bufferedReader.close();
					} catch (Throwable var11) {
						var12.addSuppressed(var11);
					}
				}

				throw var12;
			}

			if (bufferedReader != null) {
				bufferedReader.close();
			}

			return var10;
		} catch (Throwable var13) {
			throw new SnbtToNbt.StructureConversionException(filePath, var13);
		}
	}

	private void storeStructureIfChanged(CachedOutput output, SnbtToNbt.TaskResult taskResult, Path directoryPath) {
		Path path = directoryPath.resolve(taskResult.name + ".nbt");

		try {
			output.writeIfNeeded(path, taskResult.payload, taskResult.hash);
		} catch (IOException var6) {
			LOGGER.error("Couldn't write structure {} at {}", taskResult.name, path, var6);
		}
	}

	@FunctionalInterface
	public interface Filter {
		CompoundTag apply(String structureLocationPath, CompoundTag tag);
	}

	/**
	 * Wraps exceptions thrown while reading structures to include the path of the structure in the exception message.
	 */
	static class StructureConversionException extends RuntimeException {
		public StructureConversionException(Path path, Throwable cause) {
			super(path.toAbsolutePath().toString(), cause);
		}
	}

	record TaskResult(String name, byte[] payload, HashCode hash) {
	}
}