import io
import tarfile
import tempfile
import unittest
from pathlib import Path

from deploy.huggingface.backup_manager import (
    BackupArchiveError,
    build_backup_filename,
    create_backup_archive,
    extract_backup_archive,
    select_backups_to_delete,
)


class BackupManagerTests(unittest.TestCase):
    def test_build_backup_filename_uses_utc_suffix(self):
        name = build_backup_filename("20260321T102030Z")
        self.assertEqual(name, "backup-20260321T102030Z.tar.gz")

    def test_select_backups_to_delete_keeps_latest_pointer_and_newest_archives(self):
        backups = [
            "backups/latest.tar.gz",
            "backups/backup-20260320T010101Z.tar.gz",
            "backups/backup-20260321T010101Z.tar.gz",
            "backups/backup-20260322T010101Z.tar.gz",
            "notes/readme.txt",
        ]

        to_delete = select_backups_to_delete(backups, keep=2)

        self.assertEqual(to_delete, ["backups/backup-20260320T010101Z.tar.gz"])

    def test_create_and_extract_backup_archive_round_trips_directories(self):
        with tempfile.TemporaryDirectory() as tmp:
            root = Path(tmp)
            source = root / "source"
            data_dir = source / "data"
            postgres_dir = source / "postgres"
            redis_dir = source / "redis"
            data_dir.mkdir(parents=True)
            postgres_dir.mkdir()
            redis_dir.mkdir()
            (data_dir / "config.yaml").write_text("hello", encoding="utf-8")
            (postgres_dir / "PG_VERSION").write_text("16", encoding="utf-8")
            (redis_dir / "appendonly.aof").write_text("redis", encoding="utf-8")

            archive = root / "backup.tar.gz"
            create_backup_archive(
                archive,
                {
                    "data": data_dir,
                    "postgres": postgres_dir,
                    "redis": redis_dir,
                },
            )

            restore_root = root / "restore"
            restore_root.mkdir()
            extract_backup_archive(archive, restore_root)

            self.assertEqual((restore_root / "data" / "config.yaml").read_text(encoding="utf-8"), "hello")
            self.assertEqual((restore_root / "postgres" / "PG_VERSION").read_text(encoding="utf-8"), "16")
            self.assertEqual((restore_root / "redis" / "appendonly.aof").read_text(encoding="utf-8"), "redis")

    def test_extract_backup_archive_rejects_path_traversal(self):
        with tempfile.TemporaryDirectory() as tmp:
            root = Path(tmp)
            archive = root / "bad.tar.gz"
            with tarfile.open(archive, "w:gz") as tar:
                payload = b"oops"
                info = tarfile.TarInfo("../escape.txt")
                info.size = len(payload)
                tar.addfile(info, io.BytesIO(payload))

            with self.assertRaises(BackupArchiveError):
                extract_backup_archive(archive, root / "restore")


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