from pathlib import Path
import copy
import importlib.util
import json
import unittest

root = Path(__file__).resolve().parents[1]
spec = importlib.util.spec_from_file_location('metered_requester', root / 'scripts/create-metered-approval-requests.py')
m = importlib.util.module_from_spec(spec)
spec.loader.exec_module(m)

class MeteredRequesterTests(unittest.TestCase):
    def setUp(self):
        self.rows = json.loads(m.PACKET.read_text())

    def test_exact_packet_preserves_separate_human_controls(self):
        records = m.requests()
        self.assertEqual(len(records), 6)
        self.assertEqual(sum(row[1]['human_control'] for row in records), 3)
        self.assertEqual(len({row[1]['approval_id'] for row in records}), 6)

    def test_missing_duplicate_or_extra_requests_are_refused(self):
        for rows in (self.rows[:-1], self.rows + self.rows[:1], self.rows[:-1] + self.rows[:1]):
            with self.subTest(count=len(rows)), self.assertRaises(ValueError):
                m.prepare(rows)

    def test_changed_actor_native_pins_or_human_control_are_refused(self):
        for change in ('actor', 'native', 'human', 'context'):
            rows = copy.deepcopy(self.rows)
            if change == 'actor': rows[0]['request']['subject']['id'] = 'other-service'
            if change == 'native': rows[0]['decision']['provenance']['policy_package_digest'] = 'sha256:wrong'
            if change == 'human': rows[0]['request']['context']['human_control'] = False
            if change == 'context': rows[0]['decision']['binding']['context']['purpose'] = 'different action'
            with self.subTest(change=change), self.assertRaises(ValueError):
                m.prepare(rows)

    def test_frozen_packet_change_refused_before_credential_access(self):
        from unittest.mock import patch
        with patch.object(m, 'PACKET_SHA256', '0' * 64), self.assertRaises(ValueError):
            m.requests()

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