/*
 * This source code is released into the public domain.
 */

/*
 * ZFS handling.
 */

#include "config_string.hh"
#include "exec.hh"
#include "generic_error.hh"
#include "jail_zfs.hh"
#include "zfs.hh"

using namespace lfjail;
using namespace std::literals;

namespace lfjail::zfs {

config::string_option filesystem(
	"zfs.filesystem"sv,
	"The ZFS filesystem under which jails are created"sv);

config::string_option mountpoint(
	"zfs.mountpoint"sv,
	"The location where the ZFS hierarchy will be mounted"sv);

} // namespace lfjail::zfs

namespace {

/*
 * Make sure our top-level ZFS dataset exists.
 */
void ensure_jroot(context const &) {
	auto jroot = lfjail::zfs::filesystem.string();
	auto mntpt = lfjail::zfs::mountpoint.string();

	if (zfs::dataset_exists(jroot))
		return;

	auto mntptopt = std::format("mountpoint={}", mntpt);
	zfs::create_dataset(jroot, mntptopt);
}

} // anonymous namespace

namespace lfjail::zfs {

void create_for_jail(context const &ctx, jail const &jailconf) {
	if (filesystem.string().empty())
		throw generic_error("zfs.filesystem is not set");

	if (mountpoint.string().empty())
		throw generic_error("zfs.mountpoint is not set");

	ensure_jroot(ctx);

	auto const ds = filesystem.string() + "/" + jailconf.name;
	zfs::create_dataset(ds);
}

void destroy_for_jail(context const &, jail const &jailconf) {
	auto const dataset = filesystem.string() + "/" + jailconf.name;
	dataset_destroy(dataset);
}

auto jail_root(context const &ctx) -> std::string {
	std::ignore = ctx;

	auto fs = filesystem.string();
	if (fs.empty())
		throw generic_error("zfs.filesystem not set");

	return ""; // fs.mountpoint
}

} // namespace lfjail::zfs