"""Tests for datetime formula functions (R1)."""

from __future__ import annotations

from agentkit.bitable.formula.functions.datetime import (
    DATETIME_FUNCTIONS,
    _date,
    _dateadd,
    _datedif,
    _day,
    _eomonth,
    _hour,
    _minute,
    _month,
    _networkdays,
    _now,
    _second,
    _today,
    _weekday,
    _year,
)


def test_registry_has_15_functions() -> None:
    assert len(DATETIME_FUNCTIONS) == 15
    assert "DATE" in DATETIME_FUNCTIONS
    assert "NETWORKDAYS" in DATETIME_FUNCTIONS


def test_date_constructor() -> None:
    result = _date(2026, 7, 6)
    assert result == "2026-07-06T00:00:00"


def test_year_month_day() -> None:
    d = _date(2026, 7, 6)
    assert _year(d) == 2026
    assert _month(d) == 7
    assert _day(d) == 6


def test_hour_minute_second() -> None:
    dt = "2026-07-06T14:30:45"
    assert _hour(dt) == 14
    assert _minute(dt) == 30
    assert _second(dt) == 45


def test_weekday() -> None:
    # 2026-07-06 is a Monday → ISO weekday 1
    assert _weekday("2026-07-06") == 1
    # 2026-07-12 is a Sunday → ISO weekday 7
    assert _weekday("2026-07-12") == 7


def test_datedif_days() -> None:
    assert _datedif("2026-07-01", "2026-07-06", "days") == 5


def test_datedif_months() -> None:
    assert _datedif("2026-01-15", "2026-07-15", "months") == 6


def test_datedif_years() -> None:
    assert _datedif("2020-01-01", "2026-01-01", "years") == 6


def test_dateadd_days() -> None:
    assert _dateadd("2026-07-06", 5, "days") == "2026-07-11T00:00:00"


def test_dateadd_months() -> None:
    assert _dateadd("2026-01-15", 1, "months") == "2026-02-15T00:00:00"


def test_dateadd_months_clamps_day() -> None:
    # Jan 31 + 1 month → Feb 28 (2026 is not a leap year)
    assert _dateadd("2026-01-31", 1, "months") == "2026-02-28T00:00:00"


def test_networkdays() -> None:
    # 2026-07-06 (Mon) to 2026-07-10 (Fri) = 5 working days
    assert _networkdays("2026-07-06", "2026-07-10") == 5


def test_networkdays_includes_weekend() -> None:
    # 2026-07-06 (Mon) to 2026-07-12 (Sun) = 5 working days (weekend excluded)
    assert _networkdays("2026-07-06", "2026-07-12") == 5


def test_networkdays_reversed_args() -> None:
    # Should swap if start > end
    assert _networkdays("2026-07-10", "2026-07-06") == 5


def test_eomonth() -> None:
    # End of July 2026
    assert _eomonth("2026-07-06", 0) == "2026-07-31T00:00:00"


def test_eomonth_next_month() -> None:
    # End of August 2026
    assert _eomonth("2026-07-06", 1) == "2026-08-31T00:00:00"


def test_today_returns_iso_string() -> None:
    result = _today()
    assert isinstance(result, str)
    assert "T00:00:00" in result


def test_now_returns_iso_string() -> None:
    result = _now()
    assert isinstance(result, str)
    assert "T" in result


def test_none_input_returns_none_for_accessors() -> None:
    assert _year(None) is None
    assert _month(None) is None
    assert _day(None) is None


def test_empty_string_returns_none_for_accessors() -> None:
    assert _year("") is None
    assert _datedif("", "2026-07-06") is None