package net.minecraft.world.level.levelgen.structure.templatesystem.loader;

import com.mojang.datafixers.DataFixer;
import com.mojang.logging.LogUtils;
import java.io.InputStream;
import java.nio.file.Files;
import java.nio.file.LinkOption;
import java.nio.file.Path;
import java.util.Optional;
import java.util.stream.Stream;
import java.util.stream.Stream.Builder;
import net.minecraft.core.HolderGetter;
import net.minecraft.resources.FileToIdConverter;
import net.minecraft.resources.Identifier;
import net.minecraft.server.packs.PackType;
import net.minecraft.server.packs.PathPackResources;
import net.minecraft.server.packs.resources.IoSupplier;
import net.minecraft.world.level.block.Block;
import net.minecraft.world.level.levelgen.structure.templatesystem.StructureTemplate;
import org.slf4j.Logger;

public class DirectoryTemplateSource extends TemplateSource {
	private static final Logger LOGGER = LogUtils.getLogger();
	private final Path sourceDir;
	private final FileToIdConverter fileToIdConverter;
	private final boolean loadAsText;

	public DirectoryTemplateSource(
		final DataFixer fixerUpper,
		final HolderGetter<Block> blockLookup,
		final Path sourceDir,
		final PackType packType,
		final FileToIdConverter fileToIdConverter,
		final boolean loadAsText
	) {
		this(fixerUpper, blockLookup, sourceDir.resolve(packType.getDirectory()), fileToIdConverter, loadAsText);
	}

	public DirectoryTemplateSource(
		final DataFixer fixerUpper, final HolderGetter<Block> blockLookup, final Path sourceDir, final FileToIdConverter fileToIdConverter, final boolean loadAsText
	) {
		super(fixerUpper, blockLookup);
		this.sourceDir = sourceDir;
		this.fileToIdConverter = fileToIdConverter;
		this.loadAsText = loadAsText;
	}

	@Override
	public Optional<StructureTemplate> load(final Identifier id) {
		if (!Files.isDirectory(this.sourceDir, new LinkOption[0])) {
			return Optional.empty();
		} else {
			IoSupplier<InputStream> resource = PathPackResources.getResource(this.sourceDir, this.fileToIdConverter.idToFile(id));
			return resource == null
				? Optional.empty()
				: this.load(resource, this.loadAsText, e -> LOGGER.error("Couldn't load structure from {}:{}", this.sourceDir, id, e));
		}
	}

	@Override
	public Stream<Identifier> list() {
		if (!Files.isDirectory(this.sourceDir, new LinkOption[0])) {
			return Stream.empty();
		} else {
			Builder<Identifier> resultBuilder = Stream.builder();

			for (String namespace : PathPackResources.getNamespaces(this.sourceDir)) {
				PathPackResources.listResources(this.sourceDir, namespace, this.fileToIdConverter.prefix(), (id, var3) -> {
					if (this.fileToIdConverter.extensionMatches(id)) {
						resultBuilder.accept(this.fileToIdConverter.fileToId(id));
					}
				});
			}

			return resultBuilder.build();
		}
	}
}