"""Transaction tests: a failed health check must never leave the candidate active."""
import logging
from pathlib import Path
import tempfile
import unittest
from unittest.mock import patch

from jr_einvoice.maintenance import Maintenance, locked, point


class MaintenanceTest(unittest.TestCase):
    def setUp(self):
        self.tmp = tempfile.TemporaryDirectory()
        self.addCleanup(self.tmp.cleanup)
        self.root = Path(self.tmp.name)
        self.maintenance = Maintenance(self.root, logging.getLogger('maintenance-test'))
        self.state = self.maintenance.state
        self.state.mkdir()
        self.old = self.state / 'old'
        self.new = self.state / 'new'
        self.old.mkdir()
        self.new.mkdir()
        point(self.state / 'current', self.old)

    def test_success_and_manual_rollback(self):
        with patch.object(self.maintenance, 'health'):
            self.maintenance.activate(self.new)
            self.assertEqual((self.state / 'current').resolve(), self.new)
            self.maintenance.rollback()
        self.assertEqual((self.state / 'current').resolve(), self.old)
        self.assertEqual((self.state / 'previous').resolve(), self.new)

    def test_post_activation_failure_and_interrupt_restore_old(self):
        for failure in (RuntimeError('bad invoice'), KeyboardInterrupt()):
            with self.subTest(failure=type(failure).__name__):
                with patch.object(self.maintenance, 'health', side_effect=failure):
                    with self.assertRaises(type(failure)):
                        self.maintenance.activate(self.new)
                self.assertEqual((self.state / 'current').resolve(), self.old)

    def test_failed_rollback_precheck_keeps_active(self):
        point(self.state / 'previous', self.new)
        with patch.object(self.maintenance, 'health', side_effect=RuntimeError('bad')):
            with self.assertRaises(RuntimeError):
                self.maintenance.rollback()
        self.assertEqual((self.state / 'current').resolve(), self.old)

    def test_parallel_update_is_rejected(self):
        with locked(self.state):
            with self.assertRaisesRegex(RuntimeError, 'anderer'):
                with locked(self.state):
                    self.fail('lock not enforced')

    def test_download_failure_never_switches(self):
        with patch.object(self.maintenance, 'run'), patch('jr_einvoice.maintenance.install_mustang', side_effect=RuntimeError('checksum')):
            with self.assertRaises(RuntimeError):
                self.maintenance.update(True, '2.26.0')
        self.assertEqual((self.state / 'current').resolve(), self.old)

    def test_invalid_version_is_rejected_before_commands(self):
        with patch.object(self.maintenance, 'run') as run:
            with self.assertRaises(ValueError):
                self.maintenance.update(True, '../bad')
            run.assert_not_called()