"""Support for ONVIF binary sensors."""
from __future__ import annotations

from homeassistant.components.binary_sensor import (
    BinarySensorDeviceClass,
    BinarySensorEntity,
)
from homeassistant.config_entries import ConfigEntry
from homeassistant.const import STATE_ON
from homeassistant.core import HomeAssistant, callback
from homeassistant.helpers import entity_registry as er
from homeassistant.helpers.entity_platform import AddEntitiesCallback
from homeassistant.helpers.restore_state import RestoreEntity
from homeassistant.util.enum import try_parse_enum

from .base import ONVIFBaseEntity
from .const import DOMAIN
from .device import ONVIFDevice


async def async_setup_entry(
    hass: HomeAssistant,
    config_entry: ConfigEntry,
    async_add_entities: AddEntitiesCallback,
) -> None:
    """Set up a ONVIF binary sensor."""
    device: ONVIFDevice = hass.data[DOMAIN][config_entry.unique_id]

    entities = {
        event.uid: ONVIFBinarySensor(event.uid, device)
        for event in device.events.get_platform("binary_sensor")
    }

    ent_reg = er.async_get(hass)
    for entry in er.async_entries_for_config_entry(ent_reg, config_entry.entry_id):
        if entry.domain == "binary_sensor" and entry.unique_id not in entities:
            entities[entry.unique_id] = ONVIFBinarySensor(
                entry.unique_id, device, entry
            )

    async_add_entities(entities.values())
    uids_by_platform = device.events.get_uids_by_platform("binary_sensor")

    @callback
    def async_check_entities() -> None:
        """Check if we have added an entity for the event."""
        nonlocal uids_by_platform
        if not (missing := uids_by_platform.difference(entities)):
            return
        new_entities: dict[str, ONVIFBinarySensor] = {
            uid: ONVIFBinarySensor(uid, device) for uid in missing
        }
        if new_entities:
            entities.update(new_entities)
            async_add_entities(new_entities.values())

    device.events.async_add_listener(async_check_entities)


class ONVIFBinarySensor(ONVIFBaseEntity, RestoreEntity, BinarySensorEntity):
    """Representation of a binary ONVIF event."""

    _attr_should_poll = False
    _attr_unique_id: str

    def __init__(
        self, uid: str, device: ONVIFDevice, entry: er.RegistryEntry | None = None
    ) -> None:
        """Initialize the ONVIF binary sensor."""
        self._attr_unique_id = uid
        if entry is not None:
            self._attr_device_class = try_parse_enum(
                BinarySensorDeviceClass, entry.original_device_class
            )
            self._attr_entity_category = entry.entity_category
            self._attr_name = entry.name
        else:
            event = device.events.get_uid(uid)
            assert event
            self._attr_device_class = try_parse_enum(
                BinarySensorDeviceClass, event.device_class
            )
            self._attr_entity_category = event.entity_category
            self._attr_entity_registry_enabled_default = event.entity_enabled
            self._attr_name = f"{device.name} {event.name}"
            self._attr_is_on = event.value

        super().__init__(device)

    @property
    def is_on(self) -> bool | None:
        """Return true if the binary sensor is on."""
        if (event := self.device.events.get_uid(self._attr_unique_id)) is not None:
            return event.value
        return self._attr_is_on

    async def async_added_to_hass(self) -> None:
        """Connect to dispatcher listening for entity data notifications."""
        self.async_on_remove(
            self.device.events.async_add_listener(self.async_write_ha_state)
        )
        if (last_state := await self.async_get_last_state()) is not None:
            self._attr_is_on = last_state.state == STATE_ON
