from __future__ import annotations

import os
import subprocess
import unittest
from pathlib import Path


ROOT = Path(__file__).resolve().parents[1]


class PackagingTests(unittest.TestCase):
    def test_makefile_supports_src_layout(self) -> None:
        makefile = (ROOT / "Makefile").read_text(encoding="utf-8")
        self.assertIn("PYTHONPATH=src:.", makefile)

    def test_release_metadata_is_mpl_2_and_version_0_2(self) -> None:
        pyproject = (ROOT / "pyproject.toml").read_text(encoding="utf-8")
        self.assertIn('version = "0.2.0"', pyproject)
        self.assertIn('license = "MPL-2.0"', pyproject)
        license_text = (ROOT / "LICENSE").read_text(encoding="utf-8")
        self.assertIn("Mozilla Public License Version 2.0", license_text)
        debian_copyright = (ROOT / "debian/copyright").read_text(encoding="utf-8")
        self.assertIn("License: MPL-2.0", debian_copyright)

    def test_debian_dependency_is_exactly_1_14_0(self) -> None:
        control = (ROOT / "debian/control").read_text(encoding="utf-8")
        self.assertIn("sing-box (= 1.14.0)", control)

    def test_cross_release_upgrade_is_rejected_and_same_release_reinstall_allowed(self) -> None:
        preinst = (ROOT / "debian/preinst").read_text(encoding="utf-8")
        self.assertIn('[ "$1" = upgrade ] && [ "${2:-}" != "0.2.0" ]', preinst)
        self.assertIn("in-place upgrades from another release", preinst)
        self.assertIn("exit 1", preinst)

    @unittest.skipUnless(os.name == "posix", "Debian maintainer scripts require POSIX sh")
    def test_preinst_lifecycle_exit_codes(self) -> None:
        preinst = ROOT / "debian/preinst"
        cases = (
            (("install",), 0),
            (("upgrade", "0.2.0", "0.2.0"), 0),
            (("upgrade", "0.1.0", "0.2.0"), 1),
            (("upgrade", "0.2.1", "0.2.0"), 1),
        )
        for arguments, expected in cases:
            with self.subTest(arguments=arguments):
                result = subprocess.run(
                    ["/bin/sh", str(preinst), *arguments],
                    capture_output=True,
                    text=True,
                    check=False,
                )
                self.assertEqual(result.returncode, expected, result.stderr)

    def test_postinst_checks_for_legacy_state(self) -> None:
        postinst = (ROOT / "debian/postinst").read_text(encoding="utf-8")
        self.assertIn("vpn_egressctl.installcheck", postinst)

    def test_sing_box_drop_in_requires_guard(self) -> None:
        drop_in = ROOT / "packaging/systemd/sing-box.service.d/10-vpn-egress-guard.conf"
        text = drop_in.read_text(encoding="utf-8")
        self.assertIn("Requires=vpn-egress-guard.service", text)
        self.assertIn("After=vpn-egress-guard.service", text)

    def test_debian_package_installs_sing_box_drop_in(self) -> None:
        install = (ROOT / "debian/install").read_text(encoding="utf-8")
        self.assertIn(
            "packaging/systemd/sing-box.service.d/10-vpn-egress-guard.conf "
            "usr/lib/systemd/system/sing-box.service.d",
            install,
        )


if __name__ == "__main__":
    unittest.main()