"""A entity class for mobile_app."""
from homeassistant.config_entries import ConfigEntry
from homeassistant.const import CONF_WEBHOOK_ID
from homeassistant.core import callback
from homeassistant.helpers.device_registry import DeviceEntry
from homeassistant.helpers.dispatcher import async_dispatcher_connect
from homeassistant.helpers.entity import Entity

from .const import (
    ATTR_SENSOR_ATTRIBUTES,
    ATTR_SENSOR_DEVICE_CLASS,
    ATTR_SENSOR_ICON,
    ATTR_SENSOR_NAME,
    ATTR_SENSOR_TYPE,
    ATTR_SENSOR_UNIQUE_ID,
    DOMAIN,
    SIGNAL_SENSOR_UPDATE,
)
from .helpers import device_info


def sensor_id(webhook_id, unique_id):
    """Return a unique sensor ID."""
    return "{}_{}".format(webhook_id, unique_id)


class MobileAppEntity(Entity):
    """Representation of an mobile app entity."""

    def __init__(self, config: dict, device: DeviceEntry, entry: ConfigEntry):
        """Initialize the sensor."""
        self._config = config
        self._device = device
        self._entry = entry
        self._registration = entry.data
        self._sensor_id = sensor_id(
            self._registration[CONF_WEBHOOK_ID], config[ATTR_SENSOR_UNIQUE_ID]
        )
        self._entity_type = config[ATTR_SENSOR_TYPE]
        self.unsub_dispatcher = None

    async def async_added_to_hass(self):
        """Register callbacks."""
        self.unsub_dispatcher = async_dispatcher_connect(
            self.hass, SIGNAL_SENSOR_UPDATE, self._handle_update
        )

    async def async_will_remove_from_hass(self):
        """Disconnect dispatcher listener when removed."""
        if self.unsub_dispatcher is not None:
            self.unsub_dispatcher()

    @property
    def should_poll(self) -> bool:
        """Declare that this entity pushes its state to HA."""
        return False

    @property
    def name(self):
        """Return the name of the mobile app sensor."""
        return self._config[ATTR_SENSOR_NAME]

    @property
    def device_class(self):
        """Return the device class."""
        return self._config.get(ATTR_SENSOR_DEVICE_CLASS)

    @property
    def device_state_attributes(self):
        """Return the device state attributes."""
        return self._config[ATTR_SENSOR_ATTRIBUTES]

    @property
    def icon(self):
        """Return the icon to use in the frontend, if any."""
        return self._config[ATTR_SENSOR_ICON]

    @property
    def unique_id(self):
        """Return the unique ID of this sensor."""
        return self._sensor_id

    @property
    def device_info(self):
        """Return device registry information for this entity."""
        return device_info(self._registration)

    async def async_update(self):
        """Get the latest state of the sensor."""
        data = self.hass.data[DOMAIN]
        try:
            self._config = data[self._entity_type][self._sensor_id]
        except KeyError:
            return

    @callback
    def _handle_update(self, data):
        """Handle async event updates."""
        incoming_id = sensor_id(data[CONF_WEBHOOK_ID], data[ATTR_SENSOR_UNIQUE_ID])
        if incoming_id != self._sensor_id:
            return

        self._config = data
        self.async_schedule_update_ha_state()
