"""Exercise the safety gates without running cluster or PostgreSQL commands."""
import importlib.util
from pathlib import Path
import unittest

spec = importlib.util.spec_from_file_location('roles', Path(__file__).resolve().parents[1] / 'scripts/test-lab-roles.py')
roles = importlib.util.module_from_spec(spec)
spec.loader.exec_module(roles)


def db(recovery, source=None, **changes):
    return dict(dict(system_id='same', recovery=recovery, paused=False,
                     receiver='streaming' if source else None,
                     sender=roles.NODES.get(source)), **changes)


class Gates(unittest.TestCase):
    def test_demote_requires_streaming_successor(self):
        roles.guard('demote', 'DAVID-DV6', db(False), db(True, 'DAVID-DV6'))
        for peer in [db(False), db(True), db(True, 'DAVID-DV6', paused=True)]:
            with self.assertRaises(RuntimeError):
                roles.guard('demote', 'DAVID-DV6', db(False), peer)

    def test_promote_refuses_live_peer_primary(self):
        with self.assertRaises(RuntimeError):
            roles.guard('promote', 'DAVID-ELITEDESK', db(True, 'DAVID-DV6'), db(False))

    def test_promote_requires_demoted_peer_streaming_back(self):
        roles.guard('promote', 'DAVID-ELITEDESK', db(True), db(True, 'DAVID-ELITEDESK'))
        with self.assertRaises(RuntimeError):
            roles.guard('promote', 'DAVID-ELITEDESK', db(True), db(True))

    def test_identity_mismatch_refused(self):
        with self.assertRaises(RuntimeError):
            roles.guard('demote', 'DAVID-DV6', db(False), db(True, 'DAVID-DV6', system_id='other'))

    def test_rejoin_only_healthy_elitedesk_standby(self):
        roles.guard('rejoin', 'DAVID-ELITEDESK', db(True, 'DAVID-DV6'), db(False))
        for node, local, peer in [('DAVID-DV6', db(True, 'DAVID-ELITEDESK'), db(False)),
                                  ('DAVID-ELITEDESK', db(False), db(True)),
                                  ('DAVID-ELITEDESK', db(True, 'DAVID-DV6'), db(True))]:
            with self.assertRaises(RuntimeError):
                roles.guard('rejoin', node, local, peer)

    def test_pinned_versions_match_lab_snapshots(self):
        root = Path(__file__).resolve().parents[1]
        for node, name in [('DAVID-DV6', 'lab-installed-before-plugin.sha256'),
                           ('DAVID-ELITEDESK', 'lab-installed-plugin.sha256')]:
            expected = {p.removeprefix(str(roles.PROVIDER) + '/'): h for h, p in
                        (line.split('  ', 1) for line in (root / 'docs' / name).read_text().splitlines())}
            self.assertEqual(roles.PINNED[node], expected)


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