"""Support for myStrom sensors of switches/plugs."""

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

from pymystrom.pir import MyStromPir
from pymystrom.switch import MyStromSwitch

from homeassistant.components.sensor import (
    SensorDeviceClass,
    SensorEntity,
    SensorEntityDescription,
    SensorStateClass,
)
from homeassistant.const import (
    LIGHT_LUX,
    EntityCategory,
    UnitOfEnergy,
    UnitOfPower,
    UnitOfTemperature,
)
from homeassistant.core import HomeAssistant
from homeassistant.helpers.device_registry import CONNECTION_NETWORK_MAC, DeviceInfo
from homeassistant.helpers.entity_platform import AddConfigEntryEntitiesCallback
from homeassistant.util.dt import utcnow

from .const import DOMAIN, MANUFACTURER
from .models import MyStromConfigEntry


@dataclass(frozen=True, kw_only=True)
class MyStromSensorEntityDescription[_DeviceT](SensorEntityDescription):
    """Class describing mystrom sensor entities."""

    value_fn: Callable[[_DeviceT], float | None]


SENSOR_TYPES_PIR: tuple[MyStromSensorEntityDescription[MyStromPir], ...] = (
    MyStromSensorEntityDescription(
        key="temperature",
        device_class=SensorDeviceClass.TEMPERATURE,
        state_class=SensorStateClass.MEASUREMENT,
        native_unit_of_measurement=UnitOfTemperature.CELSIUS,
        value_fn=(
            lambda device: (
                float(device.temperature_compensated)
                if device.temperature_compensated is not None
                else None
            )
        ),
    ),
    MyStromSensorEntityDescription(
        key="illuminance",
        device_class=SensorDeviceClass.ILLUMINANCE,
        state_class=SensorStateClass.MEASUREMENT,
        native_unit_of_measurement=LIGHT_LUX,
        value_fn=(
            lambda device: (
                float(device.intensity) if device.intensity is not None else None
            )
        ),
    ),
)


SENSOR_TYPES_SWITCH: tuple[MyStromSensorEntityDescription[MyStromSwitch], ...] = (
    MyStromSensorEntityDescription(
        key="avg_consumption",
        translation_key="avg_consumption",
        device_class=SensorDeviceClass.POWER,
        native_unit_of_measurement=UnitOfPower.WATT,
        value_fn=lambda device: device.consumedWs,
    ),
    MyStromSensorEntityDescription(
        key="consumption",
        device_class=SensorDeviceClass.POWER,
        state_class=SensorStateClass.MEASUREMENT,
        native_unit_of_measurement=UnitOfPower.WATT,
        value_fn=lambda device: device.consumption,
    ),
    MyStromSensorEntityDescription(
        key="energy_since_boot",
        translation_key="energy_since_boot",
        device_class=SensorDeviceClass.ENERGY,
        state_class=SensorStateClass.TOTAL_INCREASING,
        native_unit_of_measurement=UnitOfEnergy.JOULE,
        suggested_unit_of_measurement=UnitOfEnergy.KILO_WATT_HOUR,
        value_fn=lambda device: device.energy_since_boot,
    ),
    MyStromSensorEntityDescription(
        key="temperature",
        device_class=SensorDeviceClass.TEMPERATURE,
        state_class=SensorStateClass.MEASUREMENT,
        native_unit_of_measurement=UnitOfTemperature.CELSIUS,
        value_fn=lambda device: device.temperature,
    ),
)


async def async_setup_entry(
    hass: HomeAssistant,
    entry: MyStromConfigEntry,
    async_add_entities: AddConfigEntryEntitiesCallback,
) -> None:
    """Set up the myStrom entities."""
    device = entry.runtime_data.device
    info = entry.runtime_data.info

    entities: list[MyStromSensorBase] = []
    match device:
        case MyStromPir():
            entities = [
                MyStromSensor(device, entry.title, description, info["mac"])
                for description in SENSOR_TYPES_PIR
                if description.value_fn(device) is not None
            ]
        case MyStromSwitch():
            entities = [
                MyStromSensor(device, entry.title, description, info["mac"])
                for description in SENSOR_TYPES_SWITCH
                if description.value_fn(device) is not None
            ]
            if device.time_since_boot is not None:
                entities.append(
                    MyStromSwitchUptimeSensor(device, entry.title, info["mac"])
                )
        case _:
            entities = []

    async_add_entities(entities)


class MyStromSensorBase(SensorEntity):
    """Base class for myStrom sensors."""

    _attr_has_entity_name = True

    def __init__(
        self,
        device: MyStromSwitch,
        name: str,
        key: str,
        mac: str,
    ) -> None:
        """Initialize the sensor."""
        self.device = device
        self._attr_unique_id = f"{mac}-{key}"
        self._attr_device_info = DeviceInfo(
            identifiers={(DOMAIN, mac)},
            connections={(CONNECTION_NETWORK_MAC, mac)},
            name=name,
            manufacturer=MANUFACTURER,
            sw_version=getattr(device, "firmware", None),
        )


class MyStromSensor[_DeviceT](MyStromSensorBase):
    """Representation of the consumption or temperature of a myStrom switch/plug."""

    entity_description: MyStromSensorEntityDescription[_DeviceT]

    _attr_has_entity_name = True

    def __init__(
        self,
        device: _DeviceT,
        name: str,
        description: MyStromSensorEntityDescription[_DeviceT],
        mac: str,
    ) -> None:
        """Initialize the sensor."""
        super().__init__(device, name, description.key, mac)
        self.entity_description = description

    @property
    def native_value(self) -> float | None:
        """Return the value of the sensor."""
        return self.entity_description.value_fn(self.device)


class MyStromSwitchUptimeSensor(MyStromSensorBase):
    """Representation of a MyStrom Switch uptime sensor."""

    entity_description = SensorEntityDescription(
        key="time_since_boot",
        device_class=SensorDeviceClass.TIMESTAMP,
        entity_category=EntityCategory.DIAGNOSTIC,
        translation_key="time_since_boot",
    )

    def __init__(
        self,
        device: MyStromSwitch,
        name: str,
        mac: str,
    ) -> None:
        """Initialize the uptime sensor."""
        super().__init__(device, name, self.entity_description.key, mac)
        self._last_value: datetime | None = None
        self._last_attributes: dict[str, Any] = {}

    @property
    def native_value(self) -> datetime | None:
        """Return the uptime of the device as a datetime."""

        if self.device.time_since_boot is None or self.device.boot_id is None:
            return None

        # Return cached value if boot_id hasn't changed
        if (
            self._last_value is not None
            and self._last_attributes.get("boot_id") == self.device.boot_id
        ):
            return self._last_value

        self._last_value = utcnow() - timedelta(seconds=self.device.time_since_boot)

        return self._last_value

    @property
    def extra_state_attributes(self) -> dict[str, Any]:
        """Return the optional state attributes."""

        self._last_attributes = {
            "boot_id": self.device.boot_id,
        }

        return self._last_attributes