from __future__ import annotations

from datetime import date

import pytest

import app.calendar_agent as calendar_module
from app.calendar_agent import CalendarAvailabilityAgent


class _FakeFreeBusy:
    def __init__(self, payload: dict[str, object]) -> None:
        self.payload = payload

    def query(self, body: dict[str, object]) -> _FakeFreeBusy:
        return self

    def execute(self) -> dict[str, object]:
        return self.payload


class _FakeCalendarService:
    def __init__(self, payload: dict[str, object]) -> None:
        self._freebusy = _FakeFreeBusy(payload)

    def freebusy(self) -> _FakeFreeBusy:
        return self._freebusy


def _build_agent(payload: dict[str, object]) -> CalendarAvailabilityAgent:
    return CalendarAvailabilityAgent(calendar_service=_FakeCalendarService(payload))


def test_weekday_boundaries_and_busy_subtraction() -> None:
    agent = _build_agent(
        {
            "calendars": {
                "primary": {
                    "busy": [
                        {
                            "start": "2026-03-09T09:00:00+01:00",
                            "end": "2026-03-09T10:00:00+01:00",
                        }
                    ]
                },
                "work": {
                    "busy": [
                        {
                            "start": "2026-03-09T09:30:00+01:00",
                            "end": "2026-03-09T11:00:00+01:00",
                        },
                        {
                            "start": "2026-03-09T12:00:00+01:00",
                            "end": "2026-03-09T12:20:00+01:00",
                        },
                    ]
                },
            }
        }
    )

    result = agent.get_available_meeting_intervals(
        start="2026-03-09T07:00:00+01:00",
        end="2026-03-09T22:00:00+01:00",
        calendar_ids=["primary", "work"],
    )

    assert result.timezone == "Europe/Paris"
    assert result.checked_calendars == ["primary", "work"]
    assert result.meeting_intervals == [
        {
            "start": "2026-03-09T08:30:00+01:00",
            "end": "2026-03-09T09:00:00+01:00",
        },
        {
            "start": "2026-03-09T11:00:00+01:00",
            "end": "2026-03-09T12:00:00+01:00",
        },
        {
            "start": "2026-03-09T12:20:00+01:00",
            "end": "2026-03-09T21:30:00+01:00",
        },
    ]


def test_saturday_window_only() -> None:
    agent = _build_agent({"calendars": {"primary": {"busy": []}}})
    result = agent.get_available_meeting_intervals(
        start="2026-03-14T08:00:00+01:00",
        end="2026-03-14T13:00:00+01:00",
        calendar_ids=None,
    )

    assert result.meeting_intervals == [
        {
            "start": "2026-03-14T09:30:00+01:00",
            "end": "2026-03-14T12:00:00+01:00",
        }
    ]


def test_sunday_excluded() -> None:
    agent = _build_agent({"calendars": {"primary": {"busy": []}}})
    result = agent.get_available_meeting_intervals(
        start="2026-03-15T08:00:00+01:00",
        end="2026-03-15T14:00:00+01:00",
        calendar_ids=None,
    )

    assert result.meeting_intervals == []


def test_france_holiday_excluded(monkeypatch) -> None:
    def _fake_country_holidays(
        country: str,
        *,
        years: range,
        observed: bool,
        subdiv: str | None = None,
    ) -> dict[date, str]:
        assert observed is False
        if country == "FR":
            return {date(2026, 7, 14): "Bastille Day"}
        if country == "CA" and subdiv == "QC":
            return {}
        return {}

    monkeypatch.setattr(calendar_module.holidays, "country_holidays", _fake_country_holidays)
    agent = _build_agent({"calendars": {"primary": {"busy": []}}})

    result = agent.get_available_meeting_intervals(
        start="2026-07-14T08:00:00+02:00",
        end="2026-07-14T22:00:00+02:00",
        calendar_ids=None,
    )

    assert result.meeting_intervals == []


def test_quebec_holiday_excluded(monkeypatch) -> None:
    def _fake_country_holidays(
        country: str,
        *,
        years: range,
        observed: bool,
        subdiv: str | None = None,
    ) -> dict[date, str]:
        assert observed is False
        if country == "FR":
            return {}
        if country == "CA" and subdiv == "QC":
            return {date(2026, 6, 24): "Saint-Jean-Baptiste Day"}
        return {}

    monkeypatch.setattr(calendar_module.holidays, "country_holidays", _fake_country_holidays)
    agent = _build_agent({"calendars": {"primary": {"busy": []}}})

    result = agent.get_available_meeting_intervals(
        start="2026-06-24T08:00:00+02:00",
        end="2026-06-24T22:00:00+02:00",
        calendar_ids=None,
    )

    assert result.meeting_intervals == []


def test_intervals_shorter_than_30_minutes_are_filtered() -> None:
    agent = _build_agent(
        {
            "calendars": {
                "primary": {
                    "busy": [
                        {
                            "start": "2026-03-09T08:40:00+01:00",
                            "end": "2026-03-09T09:30:00+01:00",
                        }
                    ]
                }
            }
        }
    )

    result = agent.get_available_meeting_intervals(
        start="2026-03-09T08:30:00+01:00",
        end="2026-03-09T09:30:00+01:00",
        calendar_ids=None,
    )

    assert result.meeting_intervals == []


def test_range_greater_than_90_days_rejected() -> None:
    agent = _build_agent({"calendars": {"primary": {"busy": []}}})

    with pytest.raises(ValueError, match="cannot exceed 90 days"):
        agent.get_available_meeting_intervals(
            start="2026-01-01T08:00:00+01:00",
            end="2026-04-02T08:00:01+02:00",
            calendar_ids=None,
        )


def test_requires_timezone_offset() -> None:
    agent = _build_agent({"calendars": {"primary": {"busy": []}}})

    with pytest.raises(ValueError, match="timezone offset"):
        agent.get_available_meeting_intervals(
            start="2026-03-10T08:00:00",
            end="2026-03-10T10:00:00+01:00",
            calendar_ids=None,
        )