"""Independent arithmetic and boundary assertions for the public worked example."""
import copy
import csv
from datetime import date
from pathlib import Path
import unittest
from review_cohort import review

BASE = Path(__file__).parent


class ReviewTests(unittest.TestCase):
    def setUp(self):
        with (BASE / 'start-cohort.csv').open(newline='') as source:
            self.rows = list(csv.DictReader(source))

    def run_review(self, rows=None, as_of='2026-11-04', days=90):
        return review(self.rows if rows is None else rows, date.fromisoformat(as_of), days)

    def test_hand_checked_example(self):
        r = self.run_review()
        self.assertEqual(r['counts'], dict(total=6, pending=2, mature=4, retained=2, early_exit=1,
            retention_unknown=1, goal_observed=2, goal_met=1, goal_not_met=1, manager_observed=1, both_observed=1))
        self.assertEqual(r['retention_coverage'], dict(numerator=3, denominator=4, percent=75.0))
        self.assertEqual(r['retained_among_known'], dict(numerator=2, denominator=3, percent=66.67))
        self.assertEqual(r['retained_cohort_lower_bound']['percent'], 50)
        self.assertEqual(r['retained_cohort_upper_bound']['percent'], 75)
        self.assertEqual(r['goal_coverage_among_confirmed_full_window']['denominator'], 2)
        self.assertEqual(r['manager_coverage_among_confirmed_full_window']['percent'], 50)
        self.assertIsNone(r['combined_quality_score'])

    def test_exit_after_checkpoint_does_not_rewrite_retention(self):
        self.assertEqual(self.run_review()['episode_checks'][1]['observation_state'], 'retained')

    def test_exit_on_checkpoint_is_not_retained(self):
        row = copy.deepcopy(self.rows[2]); row['exit_on'] = '2026-10-01'
        self.assertEqual(self.run_review([row])['counts']['early_exit'], 1)

    def test_young_episodes_remain_pending_with_no_zero_fill(self):
        r = self.run_review(self.rows[4:])
        self.assertEqual(r['counts']['pending'], 2)
        self.assertIsNone(r['retained_among_known']['percent'])
        self.assertEqual(r['counts']['goal_not_met'], 0)

    def test_empty_cohort_has_null_percentages(self):
        self.assertIsNone(self.run_review([])['retention_coverage']['percent'])

    def test_reject_duplicate_and_future_evidence(self):
        with self.assertRaises(ValueError): self.run_review([self.rows[0], self.rows[0]])
        with self.assertRaises(ValueError): self.run_review([self.rows[0]], as_of='2026-11-03')

    def test_reject_wrong_window_and_incomplete_record(self):
        row = copy.deepcopy(self.rows[0]); row['goal_window_end'] = '2026-09-28'
        with self.assertRaises(ValueError): self.run_review([row])
        row['goal_window_end'] = ''
        with self.assertRaises(ValueError): self.run_review([row])

    def test_review_point_is_configurable_and_checkpoint_is_inclusive(self):
        r = self.run_review([self.rows[4]], days=34)
        self.assertEqual(r['episode_checks'][0]['checkpoint_on'], '2026-11-04')
        self.assertEqual(r['counts']['retained'], 1)


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