"""Support for Litter-Robot sensors."""

from __future__ import annotations

from collections.abc import Callable
from dataclasses import dataclass
from datetime import datetime
from typing import Any, Generic

from pylitterbot import FeederRobot, LitterRobot, LitterRobot4, Robot

from homeassistant.components.sensor import (
    SensorDeviceClass,
    SensorEntity,
    SensorEntityDescription,
    SensorStateClass,
)
from homeassistant.const import PERCENTAGE, EntityCategory, UnitOfMass
from homeassistant.core import HomeAssistant
from homeassistant.helpers.entity_platform import AddEntitiesCallback

from .coordinator import LitterRobotConfigEntry
from .entity import LitterRobotEntity, _RobotT


def icon_for_gauge_level(gauge_level: int | None = None, offset: int = 0) -> str:
    """Return a gauge icon valid identifier."""
    if gauge_level is None or gauge_level <= 0 + offset:
        return "mdi:gauge-empty"
    if gauge_level > 70 + offset:
        return "mdi:gauge-full"
    if gauge_level > 30 + offset:
        return "mdi:gauge"
    return "mdi:gauge-low"


@dataclass(frozen=True, kw_only=True)
class RobotSensorEntityDescription(SensorEntityDescription, Generic[_RobotT]):
    """A class that describes robot sensor entities."""

    icon_fn: Callable[[Any], str | None] = lambda _: None
    value_fn: Callable[[_RobotT], float | datetime | str | None]


ROBOT_SENSOR_MAP: dict[type[Robot], list[RobotSensorEntityDescription]] = {
    LitterRobot: [  # type: ignore[type-abstract]  # only used for isinstance check
        RobotSensorEntityDescription[LitterRobot](
            key="waste_drawer_level",
            translation_key="waste_drawer",
            native_unit_of_measurement=PERCENTAGE,
            icon_fn=lambda state: icon_for_gauge_level(state, 10),
            state_class=SensorStateClass.MEASUREMENT,
            value_fn=lambda robot: robot.waste_drawer_level,
        ),
        RobotSensorEntityDescription[LitterRobot](
            key="sleep_mode_start_time",
            translation_key="sleep_mode_start_time",
            device_class=SensorDeviceClass.TIMESTAMP,
            value_fn=(
                lambda robot: robot.sleep_mode_start_time
                if robot.sleep_mode_enabled
                else None
            ),
        ),
        RobotSensorEntityDescription[LitterRobot](
            key="sleep_mode_end_time",
            translation_key="sleep_mode_end_time",
            device_class=SensorDeviceClass.TIMESTAMP,
            value_fn=(
                lambda robot: robot.sleep_mode_end_time
                if robot.sleep_mode_enabled
                else None
            ),
        ),
        RobotSensorEntityDescription[LitterRobot](
            key="last_seen",
            translation_key="last_seen",
            device_class=SensorDeviceClass.TIMESTAMP,
            entity_category=EntityCategory.DIAGNOSTIC,
            value_fn=lambda robot: robot.last_seen,
        ),
        RobotSensorEntityDescription[LitterRobot](
            key="status_code",
            translation_key="status_code",
            entity_category=EntityCategory.DIAGNOSTIC,
            device_class=SensorDeviceClass.ENUM,
            options=[
                "br",
                "ccc",
                "ccp",
                "cd",
                "csf",
                "csi",
                "cst",
                "df1",
                "df2",
                "dfs",
                "dhf",
                "dpf",
                "ec",
                "hpf",
                "off",
                "offline",
                "otf",
                "p",
                "pd",
                "pwrd",
                "pwru",
                "rdy",
                "scf",
                "sdf",
                "spf",
            ],
            value_fn=(
                lambda robot: status.lower() if (status := robot.status_code) else None
            ),
        ),
    ],
    LitterRobot4: [
        RobotSensorEntityDescription[LitterRobot4](
            key="litter_level",
            translation_key="litter_level",
            native_unit_of_measurement=PERCENTAGE,
            icon_fn=lambda state: icon_for_gauge_level(state, 10),
            state_class=SensorStateClass.MEASUREMENT,
            value_fn=lambda robot: robot.litter_level,
        ),
        RobotSensorEntityDescription[LitterRobot4](
            key="pet_weight",
            translation_key="pet_weight",
            native_unit_of_measurement=UnitOfMass.POUNDS,
            device_class=SensorDeviceClass.WEIGHT,
            state_class=SensorStateClass.MEASUREMENT,
            value_fn=lambda robot: robot.pet_weight,
        ),
    ],
    FeederRobot: [
        RobotSensorEntityDescription[FeederRobot](
            key="food_level",
            translation_key="food_level",
            native_unit_of_measurement=PERCENTAGE,
            icon_fn=lambda state: icon_for_gauge_level(state, 10),
            state_class=SensorStateClass.MEASUREMENT,
            value_fn=lambda robot: robot.food_level,
        )
    ],
}


async def async_setup_entry(
    hass: HomeAssistant,
    entry: LitterRobotConfigEntry,
    async_add_entities: AddEntitiesCallback,
) -> None:
    """Set up Litter-Robot sensors using config entry."""
    coordinator = entry.runtime_data
    async_add_entities(
        LitterRobotSensorEntity(
            robot=robot, coordinator=coordinator, description=description
        )
        for robot in coordinator.account.robots
        for robot_type, entity_descriptions in ROBOT_SENSOR_MAP.items()
        if isinstance(robot, robot_type)
        for description in entity_descriptions
    )


class LitterRobotSensorEntity(LitterRobotEntity[_RobotT], SensorEntity):
    """Litter-Robot sensor entity."""

    entity_description: RobotSensorEntityDescription[_RobotT]

    @property
    def native_value(self) -> float | datetime | str | None:
        """Return the state."""
        return self.entity_description.value_fn(self.robot)

    @property
    def icon(self) -> str | None:
        """Return the icon to use in the frontend, if any."""
        if (icon := self.entity_description.icon_fn(self.state)) is not None:
            return icon
        return super().icon