"""验证 financial._recent_quarters 的季度滚动逻辑"""

from datetime import datetime
from unittest.mock import patch

from src.fetchers import financial


def _fake_now(year: int, month: int, day: int = 15):
    """生成一个固定时间，用于 patch datetime.now()"""
    fixed = datetime(year, month, day)

    class FakeDatetime(datetime):
        @classmethod
        def now(cls, tz=None):  # noqa: ARG003
            return fixed

    return FakeDatetime


def test_count_matches():
    with patch.object(financial, "datetime", _fake_now(2026, 5, 15)):
        out = financial._recent_quarters(8)
    assert len(out) == 8


def test_first_is_current_quarter():
    # 2026-05-15 属于 Q2
    with patch.object(financial, "datetime", _fake_now(2026, 5, 15)):
        out = financial._recent_quarters(4)
    assert out[0] == (2026, 2)


def test_crosses_year_boundary():
    # 2026 Q1 → 2025 Q4 → 2025 Q3 → 2025 Q2
    with patch.object(financial, "datetime", _fake_now(2026, 2, 10)):
        out = financial._recent_quarters(4)
    assert out == [(2026, 1), (2025, 4), (2025, 3), (2025, 2)]


def test_q1_january():
    with patch.object(financial, "datetime", _fake_now(2026, 1, 1)):
        out = financial._recent_quarters(2)
    assert out == [(2026, 1), (2025, 4)]


def test_q4_december():
    with patch.object(financial, "datetime", _fake_now(2025, 12, 31)):
        out = financial._recent_quarters(2)
    assert out == [(2025, 4), (2025, 3)]