use std::{
	ffi::CString,
	fs::DirBuilder,
	io::{self, Read, Result, Write},
	os::unix::ffi::OsStrExt,
	path::Path,
};
use walkdir::WalkDir;

use super::unix;

pub fn pack<W: Write, P: AsRef<Path>, E: AsRef<Path>, I: Iterator<Item = E>>(
	archive: W,
	source: P,
	entries: I,
) -> Result<W> {
	let _chdir = unix::chdir(source)?;

	let mut ar = tar::Builder::new(archive);
	ar.mode(tar::HeaderMode::Deterministic);
	ar.follow_symlinks(false);

	for entry in entries {
		for dir_entry in WalkDir::new(entry).sort_by_file_name() {
			ar.append_path(dir_entry?.path())?;
		}
	}

	ar.into_inner()
}

pub fn unpack<R: Read, P: AsRef<Path>>(archive: R, dest: P) -> Result<()> {
	let dest_path = dest.as_ref();

	DirBuilder::new().recursive(true).create(dest_path)?;

	let mut ar = tar::Archive::new(archive);
	ar.set_preserve_permissions(true);
	ar.set_preserve_mtime(true);
	ar.set_unpack_xattrs(true);

	for entry_r in ar.entries()? {
		let mut entry = entry_r?;
		if entry.unpack_in(dest_path)? {
			let header = entry.header();
			let uid = header.uid()? as libc::uid_t;
			let gid = header.gid()? as libc::gid_t;

			let path = CString::new(dest_path.join(entry.path()?).as_os_str().as_bytes())
				.map_err(|e| io::Error::new(io::ErrorKind::Other, e))?;
			if unsafe { libc::lchown(path.as_ptr(), uid, gid) } < 0 {
				return Err(io::Error::last_os_error());
			}
		}
	}

	Ok(())
}