from __future__ import annotations

import hashlib
import json
import tempfile
import unittest
from pathlib import Path

from vpn_egressctl.errors import ValidationError
from vpn_egressctl.metadata import build_config_metadata, load_config_metadata


class MetadataTests(unittest.TestCase):
    def write(self, root: Path, value: dict) -> Path:
        path = root / "config.meta.json"
        path.write_text(json.dumps(value), encoding="utf-8")
        return path

    def test_current_metadata_is_accepted(self) -> None:
        with tempfile.TemporaryDirectory() as directory:
            data = b"{}\n"
            digest = hashlib.sha256(data).hexdigest()
            path = self.write(
                Path(directory), build_config_metadata(digest, "1.14.0")
            )
            value = load_config_metadata(
                path, config_sha256=digest, sing_box_version="1.14.0"
            )
        self.assertEqual(value["controller_version"], "0.2.0")

    def test_wrong_engine_is_rejected(self) -> None:
        with tempfile.TemporaryDirectory() as directory:
            digest = hashlib.sha256(b"{}\n").hexdigest()
            path = self.write(
                Path(directory), build_config_metadata(digest, "1.13.19")
            )
            with self.assertRaisesRegex(ValidationError, "another sing-box"):
                load_config_metadata(
                    path, config_sha256=digest, sing_box_version="1.14.0"
                )

    def test_unknown_keys_are_rejected(self) -> None:
        with tempfile.TemporaryDirectory() as directory:
            digest = hashlib.sha256(b"{}\n").hexdigest()
            metadata = build_config_metadata(digest, "1.14.0")
            metadata["future"] = True
            path = self.write(Path(directory), metadata)
            with self.assertRaisesRegex(ValidationError, "unsupported structure"):
                load_config_metadata(
                    path, config_sha256=digest, sing_box_version="1.14.0"
                )


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