import importlib.util
import sys
import unittest
from unittest import mock
from pathlib import Path


_SCRIPT = Path(__file__).parents[1] / "scripts" / "preflight-deployment.py"
_SPEC = importlib.util.spec_from_file_location("deployment_preflight", _SCRIPT)
assert _SPEC is not None and _SPEC.loader is not None
preflight = importlib.util.module_from_spec(_SPEC)
sys.modules[_SPEC.name] = preflight
_SPEC.loader.exec_module(preflight)


class DeploymentPreflightTests(unittest.TestCase):
    def test_maps_nested_container_path_to_host_source(self):
        container = {
            "Mounts": [
                {"Type": "bind", "Source": "/srv/data", "Destination": "/data"},
                {"Type": "bind", "Source": "/srv/sync", "Destination": "/data/Sync"},
            ]
        }
        mapping = preflight.map_path(container, "/data/Sync/routes/route-1")
        self.assertEqual(mapping.source, Path("/srv/sync/routes/route-1"))
        self.assertEqual(str(mapping.destination), "/data/Sync")

    def test_rejects_api_and_client_roots_from_different_host_paths(self):
        with self.assertRaisesRegex(preflight.CheckFailure, "host paths differ"):
            preflight.require_same_path(
                "Syncthing api_root/local_root",
                preflight.Mapping(Path("/srv/syncthing-config/routes"), Path("/var/syncthing")),
                preflight.Mapping(Path("/srv/sync/routes"), Path("/data/storage")),
            )

    def test_rejects_unmounted_container_path(self):
        with self.assertRaisesRegex(preflight.CheckFailure, "not backed"):
            preflight.map_path({"Mounts": []}, "/missing")

    def test_maps_future_route_through_syncthing_override(self):
        config = {
            "api_root": "/var/syncthing",
            "local_root": "/data/sync",
            "local_path_overrides": {
                "/var/syncthing/routes": "/data/qb/.archive-control-routes",
            },
        }
        self.assertEqual(
            preflight.route_local_path(config),
            "/data/qb/.archive-control-routes",
        )

    def test_qb_override_must_map_to_the_same_host_path(self):
        client = {"Mounts": [
            {"Type": "bind", "Source": "/srv/fast", "Destination": "/data/fast"},
        ]}
        qbittorrent = {"Mounts": [
            {"Type": "bind", "Source": "/srv/fast", "Destination": "/downloads/fast"},
        ]}
        preflight.require_qb_override_mappings(
            client, qbittorrent,
            {"local_path_overrides": {"/downloads/fast": "/data/fast"}},
        )
        with self.assertRaisesRegex(preflight.CheckFailure, "host paths differ"):
            preflight.require_qb_override_mappings(
                client,
                {"Mounts": [{
                    "Type": "bind", "Source": "/other", "Destination": "/downloads/fast",
                }]},
                {"local_path_overrides": {"/downloads/fast": "/data/fast"}},
            )

    def test_runs_hardlink_probe_with_qb_and_route_roots(self):
        completed = __import__("subprocess").CompletedProcess(
            args=[], returncode=0, stdout="hard-link staging probe passed\n", stderr=""
        )
        with mock.patch.object(preflight.subprocess, "run", return_value=completed) as run:
            preflight.run_hardlink_probe(
                "client", "/data/qb", "/data/qb/routes", "1001:1001"
            )
        args = run.call_args.args[0]
        self.assertEqual(args[:6], ["docker", "exec", "--user", "1001:1001", "client", "python"])
        self.assertEqual(args[-2:], ["/data/qb", "/data/qb/routes"])

    def test_hardlink_probe_failure_is_actionable(self):
        completed = __import__("subprocess").CompletedProcess(
            args=[], returncode=1, stdout="", stderr="[Errno 18] Invalid cross-device link"
        )
        with mock.patch.object(preflight.subprocess, "run", return_value=completed):
            with self.assertRaisesRegex(preflight.CheckFailure, "hard-link staging probe failed"):
                preflight.run_hardlink_probe("client", "/data/qb", "/data/qb/routes")

    def test_existing_route_directory_failure_is_actionable(self):
        completed = __import__("subprocess").CompletedProcess(
            args=[], returncode=1, stdout='{"missing":[{"folder_id":"route-1"}]}', stderr=""
        )
        with mock.patch.object(preflight.subprocess, "run", return_value=completed):
            with self.assertRaisesRegex(preflight.CheckFailure, "route directory is missing"):
                preflight.run_existing_route_directory_check("client", "/config.toml")


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