"""Run: python3 -m unittest test_opt_counter.py  (from this folder)
Expected values are the brief's T1-T11, checked against a reference implementation."""
import unittest
from datetime import date as D

from opt_counter import count_unemployment, stem_pending_window, to_ranges


def job(start, end=None, qualifying=True):
    return {"start": start, "end": end, "qualifying": qualifying}


EAD, END = D(2026, 6, 1), D(2027, 5, 31)
STEM_EAD, STEM_END, STEM_START = D(2025, 7, 1), D(2028, 6, 30), D(2026, 7, 1)
STEM_JOB = job(D(2025, 9, 19), D(2026, 6, 30))
PAST_JOB = job(D(2025, 6, 1), D(2026, 4, 30))

CASES = [
    # id, (ead_start, auth_end, as_of, jobs, stem_start), (used, limit, remaining, first_over)
    ("T1 Priya", (EAD, END, D(2026, 9, 30),
                  [job(D(2026, 7, 1), D(2026, 8, 14)), job(D(2026, 9, 1))], None), (47, 90, 43, None)),
    ("T2 no job", (EAD, END, D(2026, 6, 30), [], None), (30, 90, 60, None)),
    ("T3 weekend gap", (EAD, END, D(2026, 7, 31),
                        [job(D(2026, 6, 1), D(2026, 7, 10)), job(D(2026, 7, 13))], None), (2, 90, 88, None)),
    ("T4 non-qualifying", (EAD, END, D(2026, 6, 30), [job(D(2026, 6, 1), qualifying=False)], None),
     (30, 90, 60, None)),
    ("T5 overlap", (EAD, END, D(2026, 6, 30),
                    [job(D(2026, 6, 5), D(2026, 6, 20)), job(D(2026, 6, 10), D(2026, 6, 25))], None),
     (9, 90, 81, None)),
    ("T6 job before EAD", (EAD, END, D(2026, 6, 30), [job(D(2026, 5, 1), D(2026, 6, 10))], None),
     (20, 90, 70, None)),
    ("T7a STEM before start", (STEM_EAD, STEM_END, D(2026, 6, 30), [STEM_JOB], STEM_START), (80, 90, 10, None)),
    ("T7b STEM after start", (STEM_EAD, STEM_END, D(2026, 7, 31), [STEM_JOB], STEM_START), (111, 150, 39, None)),
    ("T8 over limit", (EAD, END, D(2026, 8, 31), [], None), (92, 90, -2, D(2026, 8, 30))),
    ("T9 as_of after auth end", (D(2025, 6, 1), D(2026, 5, 31), D(2026, 9, 30), [PAST_JOB], None),
     (31, 90, 59, None)),
    ("T10 cap-gap", (D(2025, 6, 1), D(2026, 9, 30), D(2026, 7, 15), [PAST_JOB], None), (76, 90, 14, None)),
    ("T11 leap day", (D(2028, 2, 1), D(2029, 1, 31), D(2028, 2, 29), [], None), (29, 90, 61, None)),
]


class TestCountUnemployment(unittest.TestCase):
    def test_stem_pending(self):
        jobs = [job(D(2026, 7, 1), D(2027, 5, 11))]
        cases = [  # as_of, (used, limit)
            (D(2027, 5, 31), (50, 90)),    # before the OPT end date
            (D(2027, 6, 10), (60, 150)),   # pending: OPT days carry into the 150
            (D(2027, 11, 27), (230, 150)),  # day 180
            (D(2027, 11, 28), (50, 90)),   # day 181: back to the OPT end date, as in EADly
        ]
        for as_of, expected in cases:
            with self.subTest(as_of):
                auth_end, stem_start = stem_pending_window(END, as_of)
                r = count_unemployment(EAD, auth_end, as_of, jobs, stem_start)
                self.assertEqual((r["days_used"], r["limit"]), expected)

    def test_cases(self):
        for name, args, expected in CASES:
            with self.subTest(name):
                r = count_unemployment(*args)
                got = (r["days_used"], r["limit"], r["days_remaining"], r["first_day_over_limit"])
                self.assertEqual(got, expected)
                self.assertEqual(len(r["unemployed_dates"]), r["days_used"])

    def test_weekend_gap_dates(self):
        r = count_unemployment(*CASES[2][1])
        self.assertEqual(r["unemployed_dates"], [D(2026, 7, 11), D(2026, 7, 12)])

    def test_ranges(self):
        r = count_unemployment(*CASES[0][1])
        self.assertEqual(to_ranges(r["unemployed_dates"]),
                         [[D(2026, 6, 1), D(2026, 6, 30)], [D(2026, 8, 15), D(2026, 8, 31)]])


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