"""Unit tests for the backend.services.rooms module."""

from typing import Any
from unittest.mock import AsyncMock
from unittest.mock import MagicMock

import pytest
from sqlalchemy import delete
from sqlalchemy import select
from sqlalchemy import update
from sqlalchemy.exc import NoResultFound
from sqlalchemy.exc import SQLAlchemyError
from sqlalchemy.ext.asyncio import AsyncSession

from backend.models import Room
from backend.models import RoomList
from backend.services.rooms import delete_room
from backend.services.rooms import get_room
from backend.services.rooms import get_rooms
from backend.services.rooms import new_room
from backend.services.rooms import update_room


@pytest.mark.asyncio
@pytest.mark.parametrize("mock_logger", ["backend.services.rooms"], indirect=True)
async def test_get_rooms_success(
    async_session: AsyncSession, sample_rooms: RoomList, mock_logger: MagicMock
) -> None:
    """Test successful retrieval of all rooms from the database.

    Verifies that get_rooms returns the expected list of rooms and constructs
    the correct SQLAlchemy query.

    Args:
        async_session: The asynchronous database session.
        sample_rooms: The mocked list of rooms to return.
        mock_logger: The mocked logger instance.
    """
    mock_scalars_result = AsyncMock()
    mock_scalars_result.all = MagicMock(return_value=sample_rooms)
    mock_scalars = AsyncMock(return_value=mock_scalars_result)
    async_session.scalars = mock_scalars  # type: ignore [method-assign]

    result: RoomList = await get_rooms(async_session)

    assert isinstance(result, list)
    assert len(result) == 2
    assert result == sample_rooms
    async_session.scalars.assert_called_once()
    assert async_session.scalars.call_args.args[0].compare(select(Room))


@pytest.mark.asyncio
@pytest.mark.parametrize("mock_logger", ["backend.services.rooms"], indirect=True)
async def test_get_rooms_empty(
    async_session: AsyncSession, mock_logger: MagicMock
) -> None:
    """Test retrieval of rooms when the database is empty.

    Verifies that get_rooms returns an empty list when no rooms are found.

    Args:
        async_session: The asynchronous database session.
        mock_logger: The mocked logger instance.
    """
    mock_scalars_result = AsyncMock()
    mock_scalars_result.all = MagicMock(return_value=[])
    mock_scalars = AsyncMock(return_value=mock_scalars_result)
    async_session.scalars = mock_scalars  # type: ignore [method-assign]

    result: RoomList = await get_rooms(async_session)

    assert isinstance(result, list)
    assert len(result) == 0
    async_session.scalars.assert_called_once()
    assert async_session.scalars.call_args.args[0].compare(select(Room))


@pytest.mark.asyncio
@pytest.mark.parametrize("mock_logger", ["backend.services.rooms"], indirect=True)
async def test_get_rooms_database_error(
    async_session: AsyncSession, mock_logger: MagicMock
) -> None:
    """Test handling of database errors in get_rooms.

    Verifies that get_rooms raises an exception on database failure.

    Args:
        async_session: The asynchronous database session.
        mock_logger: The mocked logger instance.
    """
    async_session.scalars = AsyncMock(  # type: ignore [method-assign]
        side_effect=SQLAlchemyError("Database error")
    )

    with pytest.raises(SQLAlchemyError):
        await get_rooms(async_session)
    async_session.scalars.assert_called_once()


@pytest.mark.asyncio
@pytest.mark.parametrize("mock_logger", ["backend.services.rooms"], indirect=True)
@pytest.mark.parametrize(
    "room_id, expected_name",
    [
        (1, "Room A"),
        (2, "Room B"),
    ],
    ids=["room1", "room2"],
)
async def test_get_room_success(
    async_session: AsyncSession,
    room_id: int,
    expected_name: str,
    mock_logger: MagicMock,
) -> None:
    """Test successful retrieval of a room by ID.

    Verifies that get_room returns the correct room and constructs the correct query.

    Args:
        async_session: The asynchronous database session.
        room_id: The ID of the room to retrieve.
        expected_name: The expected name of the room.
        mock_logger: The mocked logger instance.
    """
    room = Room(
        id=room_id,
        name=expected_name,
        location="Building 1",
        equipment="Projector",
        capacity=10,
    )
    async_session.scalar = AsyncMock(return_value=room)  # type: ignore [method-assign]

    result: Room = await get_room(async_session, room_id)

    assert result.id == room_id
    assert result.name == expected_name
    async_session.scalar.assert_called_once()
    assert async_session.scalar.call_args.args[0].compare(
        select(Room).where(Room.id == room_id)
    )


@pytest.mark.asyncio
@pytest.mark.parametrize("mock_logger", ["backend.services.rooms"], indirect=True)
@pytest.mark.parametrize(
    "room_id",
    [999, -1],
    ids=["nonexistent_id", "invalid_id"],
)
async def test_get_room_not_found(
    async_session: AsyncSession, mock_logger: MagicMock, room_id: int
) -> None:
    """Test handling of non-existent room in get_room.

    Verifies that get_room raises NoResultFound when the room is not found.

    Args:
        async_session: The asynchronous database session.
        mock_logger: The mocked logger instance.
        room_id: The ID of the room to retrieve.
    """
    async_session.scalar = AsyncMock(return_value=None)  # type: ignore [method-assign]

    with pytest.raises(NoResultFound):
        await get_room(async_session, room_id)
    async_session.scalar.assert_called_once()
    assert async_session.scalar.call_args.args[0].compare(
        select(Room).where(Room.id == room_id)
    )


@pytest.mark.asyncio
@pytest.mark.parametrize("mock_logger", ["backend.services.rooms"], indirect=True)
async def test_get_room_database_error(
    async_session: AsyncSession, mock_logger: MagicMock
) -> None:
    """Test handling of database errors in get_room.

    Verifies that get_room raises an exception on database failure.

    Args:
        async_session: The asynchronous database session.
        mock_logger: The mocked logger instance.
    """
    room_id: int = 1
    async_session.scalar = AsyncMock(  # type: ignore [method-assign]
        side_effect=SQLAlchemyError("Database error")
    )

    with pytest.raises(SQLAlchemyError):
        await get_room(async_session, room_id)
    async_session.scalar.assert_called_once()
    assert async_session.scalar.call_args.args[0].compare(
        select(Room).where(Room.id == room_id)
    )


@pytest.mark.asyncio
@pytest.mark.parametrize("mock_logger", ["backend.services.rooms"], indirect=True)
async def test_new_room_success(
    async_session: AsyncSession, mock_logger: MagicMock
) -> None:
    """Test successful creation of a new room.

    Verifies that new_room adds the room, commits the session, and returns the room.

    Args:
        async_session: The asynchronous database session.
        mock_logger: The mocked logger instance.
    """
    room = Room(
        id=1, name="Room A", location="Building 1", equipment="Projector", capacity=10
    )
    async_session.add = MagicMock()  # type: ignore [method-assign]
    async_session.commit = AsyncMock()  # type: ignore [method-assign]

    result: Room = await new_room(async_session, room)

    assert result == room
    async_session.add.assert_called_once_with(room)
    async_session.commit.assert_called_once()


@pytest.mark.asyncio
@pytest.mark.parametrize("mock_logger", ["backend.services.rooms"], indirect=True)
async def test_new_room_database_error(
    async_session: AsyncSession, mock_logger: MagicMock
) -> None:
    """Test handling of database errors in new_room.

    Verifies that new_room rolls back the session on database failure.

    Args:
        async_session: The asynchronous database session.
        mock_logger: The mocked logger instance.
    """
    room = Room(
        id=1, name="Room A", location="Building 1", equipment="Projector", capacity=10
    )
    async_session.add = MagicMock()  # type: ignore [method-assign]
    async_session.commit = AsyncMock(  # type: ignore [method-assign]
        side_effect=SQLAlchemyError("Database error")
    )
    async_session.rollback = AsyncMock()  # type: ignore [method-assign]

    with pytest.raises(SQLAlchemyError):
        await new_room(async_session, room)
    async_session.add.assert_called_once_with(room)
    async_session.commit.assert_called_once()
    async_session.rollback.assert_called_once()


@pytest.mark.asyncio
@pytest.mark.parametrize("mock_logger", ["backend.routers.rooms"], indirect=True)
async def test_update_room_success(
    async_session: AsyncSession, mock_logger: MagicMock
) -> None:
    """Test successful update of a room.

    Verifies that update_room updates the room, commits the session, and returns
    the updated room.

    Args:
        async_session: The asynchronous database session.
        mock_logger: The mocked logger instance.
    """
    room_id = 1
    update_params: dict[str, Any] = {
        "name": "Updated Room",
        "location": "Building 2",
        "equipment": "Whiteboard",
        "capacity": 15,
    }
    mock_execute_result = MagicMock(rowcount=1)
    async_session.execute = AsyncMock(  # type: ignore [method-assign]
        return_value=mock_execute_result
    )
    async_session.commit = AsyncMock()  # type: ignore [method-assign]
    updated_room = Room(id=room_id, **update_params)
    async_session.scalar = AsyncMock(  # type: ignore [method-assign]
        return_value=updated_room
    )

    result: Room = await update_room(async_session, room_id, **update_params)

    assert result == updated_room
    async_session.execute.assert_called_once()
    assert async_session.execute.call_args.args[0].compare(
        update(Room).where(Room.id == room_id).values(**update_params)
    )
    async_session.commit.assert_called_once()
    async_session.scalar.assert_called_once()
    assert async_session.scalar.call_args.args[0].compare(
        select(Room).where(Room.id == room_id)
    )


@pytest.mark.asyncio
@pytest.mark.parametrize("mock_logger", ["backend.services.rooms"], indirect=True)
async def test_update_room_not_found(
    async_session: AsyncSession, mock_logger: MagicMock
) -> None:
    """Test handling of non-existent room in update_room.

    Verifies that update_room raises ValueError when the room is not found.

    Args:
        async_session: The asynchronous database session.
        mock_logger: The mocked logger instance.
    """
    room_id = 999
    update_params: dict[str, Any] = {
        "name": "Updated Room",
        "location": "Building 2",
        "equipment": "Whiteboard",
        "capacity": 15,
    }
    mock_execute_result = MagicMock(rowcount=0)
    async_session.execute = AsyncMock(  # type: ignore [method-assign]
        return_value=mock_execute_result
    )
    async_session.rollback = AsyncMock()  # type: ignore [method-assign]

    with pytest.raises(ValueError):
        await update_room(async_session, room_id, **update_params)
    async_session.execute.assert_called_once()
    assert async_session.execute.call_args.args[0].compare(
        update(Room).where(Room.id == room_id).values(**update_params)
    )
    async_session.rollback.assert_called_once()


@pytest.mark.asyncio
@pytest.mark.parametrize("mock_logger", ["backend.services.rooms"], indirect=True)
async def test_update_room_database_error(
    async_session: AsyncSession, mock_logger: MagicMock
) -> None:
    """Test handling of database errors in update_room.

    Verifies that update_room rolls back the session on database failure.

    Args:
        async_session: The asynchronous database session.
        mock_logger: The mocked logger instance.
    """
    room_id = 1
    update_params: dict[str, Any] = {
        "name": "Updated Room",
        "location": "Building 2",
        "equipment": "Whiteboard",
        "capacity": 15,
    }
    async_session.execute = AsyncMock(  # type: ignore [method-assign]
        side_effect=SQLAlchemyError("Database error")
    )
    async_session.rollback = AsyncMock()  # type: ignore [method-assign]

    with pytest.raises(SQLAlchemyError):
        await update_room(async_session, room_id, **update_params)
    async_session.execute.assert_called_once()
    assert async_session.execute.call_args.args[0].compare(
        update(Room).where(Room.id == room_id).values(**update_params)
    )
    async_session.rollback.assert_called_once()


@pytest.mark.asyncio
@pytest.mark.parametrize("mock_logger", ["backend.services.rooms"], indirect=True)
async def test_delete_room_success(
    async_session: AsyncSession, mock_logger: MagicMock
) -> None:
    """Test successful deletion of a room.

    Verifies that delete_room deletes the room and commits the session.

    Args:
        async_session: The asynchronous database session.
        mock_logger: The mocked logger instance.
    """
    room_id = 1
    mock_execute_result = MagicMock(rowcount=1)
    async_session.execute = AsyncMock(  # type: ignore [method-assign]
        return_value=mock_execute_result
    )
    async_session.commit = AsyncMock()  # type: ignore [method-assign]

    await delete_room(async_session, room_id)

    async_session.execute.assert_called_once()
    assert async_session.execute.call_args.args[0].compare(
        delete(Room).where(Room.id == room_id)
    )
    async_session.commit.assert_called_once()


@pytest.mark.asyncio
@pytest.mark.parametrize("mock_logger", ["backend.services.rooms"], indirect=True)
async def test_delete_room_not_found(
    async_session: AsyncSession, mock_logger: MagicMock
) -> None:
    """Test handling of non-existent room in delete_room.

    Verifies that delete_room raises ValueError when the room is not found.

    Args:
        async_session: The asynchronous database session.
        mock_logger: The mocked logger instance.
    """
    room_id = 999
    mock_execute_result = MagicMock(rowcount=0)
    async_session.execute = AsyncMock(  # type: ignore [method-assign]
        return_value=mock_execute_result
    )
    async_session.rollback = AsyncMock()  # type: ignore [method-assign]

    with pytest.raises(ValueError):
        await delete_room(async_session, room_id)
    async_session.execute.assert_called_once()
    assert async_session.execute.call_args.args[0].compare(
        delete(Room).where(Room.id == room_id)
    )
    async_session.rollback.assert_called_once()


@pytest.mark.asyncio
@pytest.mark.parametrize("mock_logger", ["backend.services.rooms"], indirect=True)
async def test_delete_room_database_error(
    async_session: AsyncSession, mock_logger: MagicMock
) -> None:
    """Test handling of database errors in delete_room.

    Verifies that delete_room rolls back the session on database failure.

    Args:
        async_session: The asynchronous database session.
        mock_logger: The mocked logger instance.
    """
    room_id = 1
    async_session.execute = AsyncMock(  # type: ignore [method-assign]
        side_effect=SQLAlchemyError("Database error")
    )
    async_session.rollback = AsyncMock()  # type: ignore [method-assign]

    with pytest.raises(SQLAlchemyError):
        await delete_room(async_session, room_id)
    async_session.execute.assert_called_once()
    assert async_session.execute.call_args.args[0].compare(
        delete(Room).where(Room.id == room_id)
    )
    async_session.rollback.assert_called_once()