from __future__ import annotations

from pathlib import Path
import tempfile
import unittest
import zipfile

try:
    import pyzipper
except ImportError:  # pragma: no cover
    pyzipper = None

from govoplan_campaign.backend.services.zip_service import (
    create_zip_archive,
    zip_archive_evidence,
)


class ZipServiceTests(unittest.TestCase):
    def test_standard_password_zip_uses_zipcrypto_readable_by_stdlib(self) -> None:
        with tempfile.TemporaryDirectory() as temp_dir:
            root = Path(temp_dir)
            source = root / "source.txt"
            source.write_text("Hello Windows ZIP", encoding="utf-8")
            output = root / "standard.zip"

            create_zip_archive(output, [(source, "message.txt")], "secret", "zip_standard")

            with zipfile.ZipFile(output) as archive:
                info = archive.getinfo("message.txt")
                self.assertEqual(info.compress_type, zipfile.ZIP_DEFLATED)
                self.assertTrue(info.flag_bits & 0x1)
                self.assertEqual(archive.read("message.txt", pwd=b"secret"), b"Hello Windows ZIP")
                with self.assertRaises(RuntimeError):
                    archive.read("message.txt", pwd=b"wrong-password")

            evidence = zip_archive_evidence(
                output,
                [(source, "message.txt")],
                password_protected=True,
                method="zip_standard",
            )
            self.assertEqual("Legacy ZipCrypto", evidence["format"])
            self.assertEqual("govoplan-campaign.zipcrypto", evidence["implementation"])
            self.assertNotIn("password", evidence)
            self.assertEqual(64, len(str(evidence["archive_sha256"])))
            self.assertEqual(64, len(str(evidence["members"][0]["sha256"])))

    @unittest.skipIf(pyzipper is None, "pyzipper is not installed")
    def test_aes_password_zip_keeps_aes_encryption(self) -> None:
        with tempfile.TemporaryDirectory() as temp_dir:
            root = Path(temp_dir)
            source = root / "source.txt"
            source.write_text("Hello AES ZIP", encoding="utf-8")
            output = root / "aes.zip"

            create_zip_archive(output, [(source, "message.txt")], "secret", "aes")

            with zipfile.ZipFile(output) as archive:
                info = archive.getinfo("message.txt")
                self.assertEqual(info.compress_type, 99)
                self.assertTrue(info.flag_bits & 0x1)

            with pyzipper.AESZipFile(output) as archive:
                archive.setpassword(b"secret")
                self.assertEqual(archive.read("message.txt"), b"Hello AES ZIP")

    def test_unprotected_zip_ignores_encryption_mode(self) -> None:
        with tempfile.TemporaryDirectory() as temp_dir:
            root = Path(temp_dir)
            source = root / "source.txt"
            source.write_text("Plain ZIP", encoding="utf-8")
            output = root / "plain.zip"

            create_zip_archive(output, [(source, "message.txt")], "", "zip_standard")

            with zipfile.ZipFile(output) as archive:
                info = archive.getinfo("message.txt")
                self.assertEqual(info.compress_type, zipfile.ZIP_DEFLATED)
                self.assertFalse(info.flag_bits & 0x1)
                self.assertEqual(archive.read("message.txt"), b"Plain ZIP")

    def test_unknown_password_method_fails_without_downgrade_or_output(self) -> None:
        with tempfile.TemporaryDirectory() as temp_dir:
            root = Path(temp_dir)
            source = root / "source.txt"
            source.write_text("No downgrade", encoding="utf-8")
            output = root / "unknown.zip"

            with self.assertRaisesRegex(ValueError, "Unsupported"):
                create_zip_archive(output, [source], "secret", "unknown")

            self.assertFalse(output.exists())


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