Add occupancy sensor to the BAF integration (#75793)

Co-authored-by: J. Nick Koston <nick@koston.org>

homeassistant/components/baf/binary_sensor.py

@@ -0,0 +1,80 @@
+"""Support for Big Ass Fans binary sensors."""
+from __future__ import annotations
+
+from collections.abc import Callable
+from dataclasses import dataclass
+from typing import Optional, cast
+
+from aiobafi6 import Device
+
+from homeassistant import config_entries
+from homeassistant.components.binary_sensor import (
+    BinarySensorDeviceClass,
+    BinarySensorEntity,
+    BinarySensorEntityDescription,
+)
+from homeassistant.core import HomeAssistant, callback
+from homeassistant.helpers.entity_platform import AddEntitiesCallback
+
+from .const import DOMAIN
+from .entity import BAFEntity
+from .models import BAFData
+
+
+@dataclass
+class BAFBinarySensorDescriptionMixin:
+    """Required values for BAF binary sensors."""
+
+    value_fn: Callable[[Device], bool | None]
+
+
+@dataclass
+class BAFBinarySensorDescription(
+    BinarySensorEntityDescription,
+    BAFBinarySensorDescriptionMixin,
+):
+    """Class describing BAF binary sensor entities."""
+
+
+OCCUPANCY_SENSORS = (
+    BAFBinarySensorDescription(
+        key="occupancy",
+        name="Occupancy",
+        device_class=BinarySensorDeviceClass.OCCUPANCY,
+        value_fn=lambda device: cast(Optional[bool], device.fan_occupancy_detected),
+    ),
+)
+
+
+async def async_setup_entry(
+    hass: HomeAssistant,
+    entry: config_entries.ConfigEntry,
+    async_add_entities: AddEntitiesCallback,
+) -> None:
+    """Set up BAF binary sensors."""
+    data: BAFData = hass.data[DOMAIN][entry.entry_id]
+    device = data.device
+    sensors_descriptions: list[BAFBinarySensorDescription] = []
+    if device.has_occupancy:
+        sensors_descriptions.extend(OCCUPANCY_SENSORS)
+    async_add_entities(
+        BAFBinarySensor(device, description) for description in sensors_descriptions
+    )
+
+
+class BAFBinarySensor(BAFEntity, BinarySensorEntity):
+    """BAF binary sensor."""
+
+    entity_description: BAFBinarySensorDescription
+
+    def __init__(self, device: Device, description: BAFBinarySensorDescription) -> None:
+        """Initialize the entity."""
+        self.entity_description = description
+        super().__init__(device, f"{device.name} {description.name}")
+        self._attr_unique_id = f"{self._device.mac_address}-{description.key}"
+
+    @callback
+    def _async_update_attrs(self) -> None:
+        """Update attrs from device."""
+        description = self.entity_description
+        self._attr_is_on = description.value_fn(self._device)