"""Which days are school days, from the OpenHolidays API's two lists."""

from __future__ import annotations

from datetime import date
from pathlib import Path
from typing import Any

import httpx2
import pytest

from musicmouse.school_days import (
    HolidayCalendar,
    fetch_calendar,
    load_calendar,
    parse_holidays,
    save_calendar,
    school_day,
)


def _entry(
    start: str, end: str, name: str, *codes: str, nationwide: bool = False
) -> dict[str, Any]:
    """One entry in the API's shape (trimmed to the fields that are read)."""
    return {
        "startDate": start,
        "endDate": end,
        "name": [{"language": "DE", "text": name}],
        "nationwide": nationwide,
        "subdivisions": [{"code": code, "shortName": code[3:]} for code in codes],
    }


#: Verbatim dates from the API for Bavaria, 2026/27.
SCHOOL = [
    _entry("2026-11-02", "2026-11-06", "Herbstferien", "DE-BY"),
    _entry("2026-11-18", "2026-11-18", "Buß- und Bettag", "DE-BY"),
    _entry("2026-12-24", "2027-01-08", "Weihnachtsferien", "DE-BY"),
]
PUBLIC = [
    _entry("2026-10-03", "2026-10-03", "Tag der Deutschen Einheit", nationwide=True),
    _entry("2027-05-27", "2027-05-27", "Fronleichnam", "DE-HE", "DE-BW", "DE-BY"),
    _entry("2027-08-09", "2027-08-09", "Friedensfest", "DE-BY-AU"),
]


def _calendar(subdivision: str = "DE-BY") -> HolidayCalendar:
    return HolidayCalendar(
        fetched=date(2026, 10, 1),
        subdivision=subdivision,
        school=parse_holidays(SCHOOL),
        public=parse_holidays(PUBLIC),
    )


@pytest.mark.parametrize(
    ("day", "expected"),
    [
        (date(2026, 10, 5), (True, None)),  # a plain Monday
        (date(2026, 10, 10), (False, "Wochenende")),
        (date(2026, 10, 11), (False, "Wochenende")),
        (date(2026, 11, 4), (False, "Herbstferien")),
        (date(2026, 11, 9), (True, None)),  # the Monday after
        (date(2026, 11, 18), (False, "Buß- und Bettag")),
        (date(2027, 1, 7), (False, "Weihnachtsferien")),  # spans the new year
        (date(2027, 5, 27), (False, "Fronleichnam")),
    ],
)
def test_school_days_in_bavaria(day: date, expected: tuple[bool, str | None]) -> None:
    assert school_day(day, _calendar()) == expected


def test_a_nationwide_holiday_on_a_weekend_is_still_the_weekend() -> None:
    assert school_day(date(2026, 10, 3), _calendar()) == (False, "Wochenende")


def test_a_city_holiday_counts_only_for_that_city() -> None:
    friedensfest = date(2027, 8, 9)  # a Monday; pretend it is not in the summer holidays
    assert school_day(friedensfest, _calendar("DE-BY")) == (True, None)
    assert school_day(friedensfest, _calendar("DE-BY-AU")) == (False, "Friedensfest")


def test_a_city_also_gets_its_states_holidays() -> None:
    assert school_day(date(2026, 11, 4), _calendar("DE-BY-AU")) == (False, "Herbstferien")


def test_without_a_calendar_only_the_weekend_is_known() -> None:
    assert school_day(date(2026, 10, 5), None) == (None, None)
    assert school_day(date(2026, 10, 10), None) == (False, "Wochenende")


def test_entries_that_do_not_parse_are_skipped() -> None:
    raw = [{"startDate": "nope"}, {"name": []}, SCHOOL[0]]
    assert [holiday.name for holiday in parse_holidays(raw)] == ["Herbstferien"]


def test_the_cache_round_trips(tmp_path: Path) -> None:
    path = tmp_path / "cache" / "holidays.json"
    save_calendar(path, _calendar())
    assert load_calendar(path, "DE-BY") == _calendar()


def test_a_cache_for_another_subdivision_is_not_used(tmp_path: Path) -> None:
    path = tmp_path / "holidays.json"
    save_calendar(path, _calendar())
    assert load_calendar(path, "DE-BW") is None


def test_a_broken_or_missing_cache_is_no_cache(tmp_path: Path) -> None:
    path = tmp_path / "holidays.json"
    assert load_calendar(path, "DE-BY") is None
    path.write_text("{not json")
    assert load_calendar(path, "DE-BY") is None


async def test_fetching_asks_for_the_state_and_both_lists() -> None:
    requests: list[httpx2.Request] = []

    def handler(request: httpx2.Request) -> httpx2.Response:
        requests.append(request)
        body = SCHOOL if request.url.path == "/SchoolHolidays" else PUBLIC
        return httpx2.Response(200, json=body)

    async with httpx2.AsyncClient(transport=httpx2.MockTransport(handler)) as client:
        calendar = await fetch_calendar(client, "DE-BY-AU", date(2026, 10, 1))

    assert [r.url.path for r in requests] == ["/SchoolHolidays", "/PublicHolidays"]
    assert all(r.url.params["subdivisionCode"] == "DE-BY" for r in requests)
    assert all(r.url.params["countryIsoCode"] == "DE" for r in requests)
    assert calendar.subdivision == "DE-BY-AU"
    assert calendar.fetched == date(2026, 10, 1)
    assert len(calendar.school) == 3
    assert len(calendar.public) == 3


async def test_a_failed_fetch_raises() -> None:
    transport = httpx2.MockTransport(lambda _: httpx2.Response(503))
    async with httpx2.AsyncClient(transport=transport) as client:
        with pytest.raises(httpx2.HTTPStatusError):
            await fetch_calendar(client, "DE-BY", date(2026, 10, 1))