import hashlib
import importlib.util
import json
from pathlib import Path
import subprocess
import tarfile
import tempfile
import unittest


ROOT = Path(__file__).resolve().parents[1]
spec = importlib.util.spec_from_file_location("package_source", ROOT / "deploy" / "package_source.py")
package_source = importlib.util.module_from_spec(spec)
spec.loader.exec_module(package_source)


def run(repository: Path, *arguments: str) -> str:
    result = subprocess.run(
        ["git", "-C", str(repository), *arguments],
        check=True,
        capture_output=True,
        text=True,
    )
    return result.stdout.strip()


class PackageSourceTests(unittest.TestCase):
    def repository(self, root: Path, dotnet_version: str = "1.2.3", web_version: str = "1.2.3") -> tuple[Path, str]:
        repository = root / "repository"
        (repository / "web").mkdir(parents=True)
        run(repository, "init")
        run(repository, "config", "user.name", "GuestOps Test")
        run(repository, "config", "user.email", "guestops@example.invalid")
        run(repository, "config", "core.autocrlf", "false")
        (repository / "Directory.Build.props").write_text(
            f"<Project><PropertyGroup><Version>{dotnet_version}</Version></PropertyGroup></Project>\n",
            encoding="utf-8",
        )
        (repository / "web" / "package.json").write_text(
            json.dumps({"version": web_version}) + "\n", encoding="utf-8"
        )
        (repository / "application.txt").write_text("committed application\n", encoding="utf-8")
        run(repository, "add", ".")
        run(repository, "commit", "-m", "fixture")
        return repository, run(repository, "rev-parse", "HEAD")

    def test_packages_only_the_selected_commit_and_records_identity(self):
        with tempfile.TemporaryDirectory() as directory:
            root = Path(directory)
            repository, commit = self.repository(root)
            (repository / "application.txt").write_text("uncommitted change\n", encoding="utf-8")

            archive, record_path, record = package_source.build_package(repository, commit, root / "output")

            self.assertEqual(record["commit"], commit)
            self.assertEqual(record["version"], "1.2.3")
            self.assertEqual(record["artifact"]["sha256"], hashlib.sha256(archive.read_bytes()).hexdigest())
            self.assertEqual(json.loads(record_path.read_text(encoding="utf-8")), record)
            with tarfile.open(archive, "r:gz") as package:
                member = package.extractfile("GuestOps-1.2.3/application.txt")
                self.assertIsNotNone(member)
                self.assertEqual(member.read().decode("utf-8").strip(), "committed application")

    def test_same_commit_produces_identical_package(self):
        with tempfile.TemporaryDirectory() as directory:
            root = Path(directory)
            repository, commit = self.repository(root)
            first, _, _ = package_source.build_package(repository, commit, root / "first")
            second, _, _ = package_source.build_package(repository, commit, root / "second")
            self.assertEqual(first.read_bytes(), second.read_bytes())

    def test_rejects_mismatched_versions_and_existing_output(self):
        with tempfile.TemporaryDirectory() as directory:
            root = Path(directory)
            repository, commit = self.repository(root, web_version="1.2.4")
            with self.assertRaisesRegex(ValueError, "versions differ"):
                package_source.build_package(repository, commit, root / "output")

        with tempfile.TemporaryDirectory() as directory:
            root = Path(directory)
            repository, commit = self.repository(root)
            package_source.build_package(repository, commit, root / "output")
            with self.assertRaisesRegex(ValueError, "not overwritten"):
                package_source.build_package(repository, commit, root / "output")


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