package net.minecraft.world.level.validation;

import java.io.IOException;
import java.nio.file.FileVisitResult;
import java.nio.file.Files;
import java.nio.file.LinkOption;
import java.nio.file.NoSuchFileException;
import java.nio.file.Path;
import java.nio.file.PathMatcher;
import java.nio.file.SimpleFileVisitor;
import java.nio.file.attribute.BasicFileAttributes;
import java.util.ArrayList;
import java.util.List;

public class DirectoryValidator {
	private final PathMatcher symlinkTargetAllowList;

	public DirectoryValidator(PathMatcher symlinkTargetAllowList) {
		this.symlinkTargetAllowList = symlinkTargetAllowList;
	}

	public void validateSymlink(Path directory, List<ForbiddenSymlinkInfo> entries) throws IOException {
		Path path = Files.readSymbolicLink(directory);
		if (!this.symlinkTargetAllowList.matches(path)) {
			entries.add(new ForbiddenSymlinkInfo(directory, path));
		}
	}

	public List<ForbiddenSymlinkInfo> validateSymlink(Path directory) throws IOException {
		List<ForbiddenSymlinkInfo> list = new ArrayList();
		this.validateSymlink(directory, list);
		return list;
	}

	public List<ForbiddenSymlinkInfo> validateDirectory(Path directory, boolean validateSymlinks) throws IOException {
		List<ForbiddenSymlinkInfo> list = new ArrayList();

		BasicFileAttributes basicFileAttributes;
		try {
			basicFileAttributes = Files.readAttributes(directory, BasicFileAttributes.class, LinkOption.NOFOLLOW_LINKS);
		} catch (NoSuchFileException var6) {
			return list;
		}

		if (basicFileAttributes.isRegularFile()) {
			throw new IOException("Path " + directory + " is not a directory");
		} else {
			if (basicFileAttributes.isSymbolicLink()) {
				if (!validateSymlinks) {
					this.validateSymlink(directory, list);
					return list;
				}

				directory = Files.readSymbolicLink(directory);
			}

			this.validateKnownDirectory(directory, list);
			return list;
		}
	}

	public void validateKnownDirectory(Path directory, List<ForbiddenSymlinkInfo> forbiddenSymlinkInfos) throws IOException {
		Files.walkFileTree(directory, new SimpleFileVisitor<Path>() {
			private void validateSymlink(Path path, BasicFileAttributes attributes) throws IOException {
				if (attributes.isSymbolicLink()) {
					DirectoryValidator.this.validateSymlink(path, forbiddenSymlinkInfos);
				}
			}

			public FileVisitResult preVisitDirectory(Path dir, BasicFileAttributes attributes) throws IOException {
				this.validateSymlink(dir, attributes);
				return super.preVisitDirectory(dir, attributes);
			}

			public FileVisitResult visitFile(Path file, BasicFileAttributes attributes) throws IOException {
				this.validateSymlink(file, attributes);
				return super.visitFile(file, attributes);
			}
		});
	}
}