import hashlib
import importlib.util
import tempfile
import unittest
from pathlib import Path


MODULE_PATH = Path(__file__).parents[2] / "autoinstall/offline/prepare-python-profile-operation.py"
SPEC = importlib.util.spec_from_file_location("prepare_python_profile_operation", MODULE_PATH)
MODULE = importlib.util.module_from_spec(SPEC)
assert SPEC.loader
SPEC.loader.exec_module(MODULE)


class PreparePythonProfileOperationTests(unittest.TestCase):
    def test_prepares_and_resumes_without_mutating_target(self):
        with tempfile.TemporaryDirectory() as directory:
            root = Path(directory)
            target = root / "venv"
            target.mkdir()
            (target / "old").write_text("old")
            wheels = root / "wheels"
            wheels.mkdir()
            wheel = wheels / "torch-cpu.whl"
            wheel.write_bytes(b"cpu")
            contract = {"profiles": {"cpu-only": {
                "required": {wheel.name: hashlib.sha256(b"cpu").hexdigest()},
                "forbidden_filename_patterns": ["cu12"],
            }}}
            receipt = {
                "schema": "com.cezen.nexus-one.profile-membership-verification-receipt.v1",
                "environment": "test", "result": "verified", "manifest_sha256": "a" * 64,
                "namespace": "offline-workstation/python-runtime-profiles", "profiles": ["cpu-only"],
            }
            args = ({"architecture": "amd64"}, receipt, "auto", "op-1", root / "journal.json",
                    target, root / "checkpoint", contract, wheels, True)
            first = MODULE.prepare(*args)
            second = MODULE.prepare(*args)
            self.assertEqual(first["checkpoint_id"], second["checkpoint_id"])
            self.assertEqual((target / "old").read_text(), "old")
            self.assertFalse(first["mutation_performed"])

    def test_invalid_payload_creates_no_journal_or_checkpoint(self):
        with tempfile.TemporaryDirectory() as directory:
            root = Path(directory)
            wheels = root / "wheels"
            wheels.mkdir()
            receipt = {
                "schema": "com.cezen.nexus-one.profile-membership-verification-receipt.v1",
                "environment": "test", "result": "verified", "manifest_sha256": "a" * 64,
                "namespace": "offline-workstation/python-runtime-profiles", "profiles": ["cpu-only"],
            }
            journal = root / "journal.json"
            checkpoint = root / "checkpoint"
            with self.assertRaisesRegex(ValueError, "PROFILE_PAYLOAD_INVALID"):
                MODULE.prepare({"architecture": "amd64"}, receipt, "auto", "op-1", journal,
                               root / "target", checkpoint,
                               {"profiles": {"cpu-only": {"required": {"missing.whl": "0" * 64}}}},
                               wheels, True)
            self.assertFalse(journal.exists())
            self.assertFalse(checkpoint.exists())


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