"""Support for Fronius binary sensors."""

from dataclasses import dataclass
from typing import TYPE_CHECKING, override

from homeassistant.components.binary_sensor import (
    BinarySensorEntity,
    BinarySensorEntityDescription,
)
from homeassistant.const import EntityCategory, Platform
from homeassistant.core import HomeAssistant, callback
from homeassistant.helpers.entity_platform import AddConfigEntryEntitiesCallback

from .entity import FroniusEntity, FroniusEntityDescription

if TYPE_CHECKING:
    from . import FroniusConfigEntry
    from .coordinator import FroniusPowerFlowUpdateCoordinator


PARALLEL_UPDATES = 0


@dataclass(frozen=True)
class FroniusBinarySensorEntityDescription(
    FroniusEntityDescription, BinarySensorEntityDescription
):
    """Describes Fronius binary sensor entity."""


POWER_FLOW_BINARY_SENSOR_DESCRIPTIONS: list[FroniusBinarySensorEntityDescription] = [
    FroniusBinarySensorEntityDescription(
        key="backup_mode",
    ),
    FroniusBinarySensorEntityDescription(
        key="battery_standby",
        entity_category=EntityCategory.DIAGNOSTIC,
    ),
]


async def async_setup_entry(
    hass: HomeAssistant,
    config_entry: FroniusConfigEntry,
    async_add_entities: AddConfigEntryEntitiesCallback,
) -> None:
    """Set up Fronius binary sensor entities based on a config entry."""
    solar_net = config_entry.runtime_data
    if solar_net.power_flow_coordinator is not None:
        solar_net.power_flow_coordinator.add_entities_for_seen_keys(
            async_add_entities, Platform.BINARY_SENSOR, PowerFlowBinarySensor
        )


class PowerFlowBinarySensor(FroniusEntity, BinarySensorEntity):
    """Defines a Fronius power flow binary sensor entity."""

    entity_description: FroniusBinarySensorEntityDescription

    def __init__(
        self,
        coordinator: FroniusPowerFlowUpdateCoordinator,
        description: FroniusBinarySensorEntityDescription,
        solar_net_id: str,
    ) -> None:
        """Set up an individual Fronius power flow binary sensor."""
        super().__init__(coordinator, description, solar_net_id)
        self._attr_is_on = self._device_data()[self.response_key]["value"]
        # SolarNet device is already created in FroniusSolarNet._create_solar_net_device
        self._attr_device_info = coordinator.solar_net.system_device_info
        self._attr_unique_id = (
            f"{coordinator.solar_net.solar_net_device_id}-power_flow-{description.key}"
        )

    @callback
    @override
    def _handle_coordinator_update(self) -> None:
        """Handle updated data from the coordinator."""
        try:
            self._attr_is_on = self._device_data()[self.response_key]["value"]
        except KeyError:
            # KeyError: raised when omitted in response, e.g. when backup power
            # is deactivated after the entity was created
            self._attr_is_on = None
        self.async_write_ha_state()