"""Tests for fable_*_event tools."""
from datetime import datetime
from unittest.mock import AsyncMock, MagicMock, patch

import pytest

from fabledassistant.mcp._context import _user_id_ctx
from fabledassistant.mcp.tools.events import (
    fable_list_events, fable_create_event, fable_get_event,
    fable_update_event, fable_delete_event,
)


@pytest.fixture(autouse=True)
def _bind_user():
    token = _user_id_ctx.set(7)
    yield
    _user_id_ctx.reset(token)


def _fake_event(**overrides) -> MagicMock:
    e = MagicMock()
    base = {
        "id": 1, "title": "ev", "start_dt": "2026-06-01T10:00:00",
        "duration_minutes": 30, "all_day": False,
        "location": "", "description": "",
    }
    base.update(overrides)
    e.to_dict.return_value = base
    return e


@pytest.mark.asyncio
async def test_list_events_passes_datetime_range():
    mock = AsyncMock(return_value=[
        {"id": 1, "title": "morning standup"},
    ])
    with patch("fabledassistant.mcp.tools.events.events_svc.list_events", mock):
        out = await fable_list_events(date_from="2026-06-01", date_to="2026-06-08")
    args, _ = mock.call_args
    assert args[0] == 7  # user_id
    assert args[1] == datetime(2026, 6, 1)
    assert args[2] == datetime(2026, 6, 8)
    assert out["total"] == 1


@pytest.mark.asyncio
async def test_create_event_combines_date_and_time():
    e = _fake_event()
    mock = AsyncMock(return_value=e)
    with patch("fabledassistant.mcp.tools.events.events_svc.create_event", mock):
        await fable_create_event(
            title="standup", start_date="2026-06-01", start_time="09:30",
            duration_minutes=15,
        )
    kwargs = mock.call_args.kwargs
    assert kwargs["start_dt"] == datetime(2026, 6, 1, 9, 30)
    assert kwargs["duration_minutes"] == 15


@pytest.mark.asyncio
async def test_create_event_zero_duration_means_point_event():
    """duration_minutes=0 must map to None at the service layer (NULL = point)."""
    e = _fake_event()
    mock = AsyncMock(return_value=e)
    with patch("fabledassistant.mcp.tools.events.events_svc.create_event", mock):
        await fable_create_event(title="x", start_date="2026-06-01")
    assert mock.call_args.kwargs["duration_minutes"] is None


@pytest.mark.asyncio
async def test_get_event_raises_when_not_found():
    with patch(
        "fabledassistant.mcp.tools.events.events_svc.get_event",
        AsyncMock(return_value=None),
    ):
        with pytest.raises(ValueError, match="event 999 not found"):
            await fable_get_event(event_id=999)


@pytest.mark.asyncio
async def test_update_event_only_sends_non_default_fields():
    e = _fake_event()
    mock = AsyncMock(return_value=e)
    with patch("fabledassistant.mcp.tools.events.events_svc.update_event", mock):
        await fable_update_event(event_id=1, title="new title")
    args, kwargs = mock.call_args
    assert args == (7, 1)
    assert kwargs == {"title": "new title"}


@pytest.mark.asyncio
async def test_update_event_duration_minus_one_means_unchanged():
    e = _fake_event()
    mock = AsyncMock(return_value=e)
    with patch("fabledassistant.mcp.tools.events.events_svc.update_event", mock):
        await fable_update_event(event_id=1, duration_minutes=-1)
    assert "duration_minutes" not in mock.call_args.kwargs


@pytest.mark.asyncio
async def test_update_event_duration_zero_clears_to_point():
    """duration_minutes=0 means "set to point event" (NULL)."""
    e = _fake_event()
    mock = AsyncMock(return_value=e)
    with patch("fabledassistant.mcp.tools.events.events_svc.update_event", mock):
        await fable_update_event(event_id=1, duration_minutes=0)
    assert mock.call_args.kwargs["duration_minutes"] is None


@pytest.mark.asyncio
async def test_update_event_requires_both_date_and_time_to_move():
    e = _fake_event()
    mock = AsyncMock(return_value=e)
    with patch("fabledassistant.mcp.tools.events.events_svc.update_event", mock):
        await fable_update_event(event_id=1, start_date="2026-06-02")
        # Only start_date, no start_time → start_dt NOT in fields
        assert "start_dt" not in mock.call_args.kwargs

        mock.reset_mock()
        await fable_update_event(
            event_id=1, start_date="2026-06-02", start_time="11:00",
        )
        assert mock.call_args.kwargs["start_dt"] == datetime(2026, 6, 2, 11)


@pytest.mark.asyncio
async def test_update_event_raises_when_not_found():
    with patch(
        "fabledassistant.mcp.tools.events.events_svc.update_event",
        AsyncMock(return_value=None),
    ):
        with pytest.raises(ValueError, match="event 999 not found"):
            await fable_update_event(event_id=999, title="x")


@pytest.mark.asyncio
async def test_delete_event_checks_existence_then_returns_confirmation():
    fake = _fake_event()
    with patch(
        "fabledassistant.mcp.tools.events.events_svc.get_event",
        AsyncMock(return_value=fake),
    ), patch(
        "fabledassistant.mcp.tools.events.events_svc.delete_event",
        AsyncMock(return_value=None),
    ):
        result = await fable_delete_event(event_id=7)
    assert result == "Event 7 deleted."


@pytest.mark.asyncio
async def test_delete_event_raises_when_not_found():
    with patch(
        "fabledassistant.mcp.tools.events.events_svc.get_event",
        AsyncMock(return_value=None),
    ):
        with pytest.raises(ValueError, match="event 999 not found"):
            await fable_delete_event(event_id=999)