"""Trait for managing room mappings on Roborock devices."""

import logging
from dataclasses import dataclass

from roborock.data import HomeData, HomeDataRoom, NamedRoomMapping, RoborockBase
from roborock.devices.traits.v1 import common
from roborock.exceptions import RoborockParsingException
from roborock.roborock_typing import RoborockCommand
from roborock.web_api import UserWebApiClient

_LOGGER = logging.getLogger(__name__)


@dataclass
class Rooms(RoborockBase):
    """Dataclass representing a collection of room mappings."""

    rooms: list[NamedRoomMapping] | None = None
    """List of room mappings."""

    @property
    def room_map(self) -> dict[int, NamedRoomMapping]:
        """Returns a mapping of segment_id to NamedRoomMapping."""
        if self.rooms is None:
            return {}
        return {room.segment_id: room for room in self.rooms}

    def with_room_names(self, name_map: dict[str, str]) -> "Rooms":
        """Create a new Rooms object with updated room names."""
        return Rooms(
            rooms=[
                NamedRoomMapping(
                    segment_id=room.segment_id,
                    iot_id=room.iot_id,
                    raw_name=name_map.get(room.iot_id),
                )
                for room in self.rooms or []
            ]
        )


class RoomsConverter(common.V1TraitDataConverter):
    """Converts response objects to Rooms."""

    def convert(self, response: common.V1ResponseData) -> Rooms:
        """Parse the response from the device into a list of NamedRoomMapping."""
        if not isinstance(response, list):
            raise ValueError(f"Unexpected RoomsTrait response format: {response!r}")
        segment_map = self.extract_segment_map(response)
        return Rooms(
            rooms=[NamedRoomMapping(segment_id=segment_id, iot_id=iot_id) for segment_id, iot_id in segment_map.items()]
        )

    @staticmethod
    def extract_segment_map(response: list) -> dict[int, str]:
        """Extract a segment_id -> iot_id mapping from the response.

        The response format can be either a flat list of [segment_id, iot_id] or a
        list of lists, where each inner list is a pair of [segment_id, iot_id]. This
        function normalizes the response into a dict of segment_id to iot_id.

        NOTE: We currently only partial samples of the room mapping formats, so
        improving test coverage with samples from a real device with this format
        would be helpful.
        """
        if len(response) == 2 and not isinstance(response[0], list):
            segment_id, iot_id = response[0], response[1]
            return {segment_id: str(iot_id)}

        segment_map: dict[int, str] = {}
        for part in response:
            if not isinstance(part, list) or len(part) < 2:
                _LOGGER.warning("Unexpected room mapping entry format: %r", part)
                continue
            segment_id, iot_id = part[0], part[1]
            segment_map[segment_id] = str(iot_id)
        return segment_map


class RoomsTrait(Rooms, common.V1TraitMixin):
    """Trait for managing the room mappings of Roborock devices."""

    command = RoborockCommand.GET_ROOM_MAPPING
    converter = RoomsConverter()

    def __init__(self, home_data: HomeData, web_api: UserWebApiClient) -> None:
        """Initialize the RoomsTrait."""
        super().__init__()
        self._home_data = home_data
        self._web_api = web_api
        self._discovered_iot_ids: set[str] = set()

    async def refresh(self) -> None:
        """Refresh room mappings and backfill unknown room names from the web API."""
        response = await self.rpc_channel.send_command(self.command)
        if not isinstance(response, list):
            raise RoborockParsingException(
                trait_name=type(self).__name__,
                command=self.command,
                payload=response,
                inner_error="Unexpected RoomsTrait response format",
            )

        segment_map = RoomsConverter.extract_segment_map(response)
        # Track all iot ids seen before. Refresh the room list when new ids are found.
        new_iot_ids = set(segment_map.values()) - set(self._home_data.rooms_map.keys())
        if new_iot_ids - self._discovered_iot_ids:
            _LOGGER.debug("Refreshing room list to discover new room names")
            if updated_rooms := await self._refresh_rooms():
                _LOGGER.debug("Updating rooms: %s", list(updated_rooms))
                self._home_data.rooms = updated_rooms
            self._discovered_iot_ids.update(new_iot_ids)
        try:
            rooms = self.converter.convert(response)
        except (TypeError, ValueError) as err:
            raise RoborockParsingException(
                trait_name=type(self).__name__,
                command=self.command,
                payload=response,
                inner_error=err,
            ) from err

        rooms = rooms.with_room_names(self._home_data.rooms_name_map)
        common.merge_trait_values(self, rooms)

    async def _refresh_rooms(self) -> list[HomeDataRoom]:
        """Fetch the latest rooms from the web API."""
        try:
            return await self._web_api.get_rooms()
        except Exception:
            _LOGGER.debug("Failed to fetch rooms from web API", exc_info=True)
            return []
