"""Binary sensor platform for Olimex ESP32-C6-EVB."""
import logging
from homeassistant.components.binary_sensor import BinarySensorEntity
from homeassistant.config_entries import ConfigEntry
from homeassistant.core import HomeAssistant, callback
from homeassistant.helpers.entity_platform import AddEntitiesCallback
from homeassistant.helpers.dispatcher import async_dispatcher_connect

from .const import DOMAIN, NUM_INPUTS

_LOGGER = logging.getLogger(__name__)


async def async_setup_entry(
    hass: HomeAssistant,
    entry: ConfigEntry,
    async_add_entities: AddEntitiesCallback,
) -> None:
    """Set up binary sensor entities for inputs."""
    data = hass.data[DOMAIN][entry.entry_id]

    sensors = [
        OlimexInputSensor(hass, entry, input_num)
        for input_num in range(1, NUM_INPUTS + 1)
    ]
    async_add_entities(sensors, update_before_add=False)


class OlimexInputSensor(BinarySensorEntity):
    """Binary sensor for Olimex input pin.

    State is driven exclusively by webhook POSTs from the board.
    No polling is performed.
    """

    _attr_should_poll = False

    def __init__(self, hass: HomeAssistant, entry: ConfigEntry, input_num: int):
        """Initialize the sensor."""
        self.hass = hass
        self._entry = entry
        self._input_num = input_num
        self._attr_name = f"Input {input_num}"
        self._attr_unique_id = f"{entry.entry_id}_input_{input_num}"
        self._state = False

    async def async_added_to_hass(self):
        """Subscribe to webhook dispatcher when entity is added."""
        signal = f"{DOMAIN}_input_{self._input_num}_event"
        self.async_on_remove(
            async_dispatcher_connect(self.hass, signal, self._handle_webhook_event)
        )
        await super().async_added_to_hass()

    @callback
    def _handle_webhook_event(self, state):
        """Handle real-time input event received via webhook from the board."""
        # Board already inverts pull-up logic before sending:
        # state=True means pressed, state=False means released
        self._state = state
        _LOGGER.debug(
            "Input %d webhook event: state=%s (sensor is_on=%s)",
            self._input_num, state, self._state
        )
        self.async_write_ha_state()

    @property
    def is_on(self):
        """Return True if input is pressed."""
        return self._state

    @property
    def device_info(self):
        """Return device information."""
        try:
            host = self._entry.data.get('host', 'unknown')
            return {
                "identifiers": {(DOMAIN, self._entry.entry_id)},
                "name": f"Olimex ESP32-C6 ({host})",
                "manufacturer": "Olimex",
                "model": "ESP32-C6-EVB",
            }
        except Exception as err:
            _LOGGER.debug("Error getting device info: %s", err)
            return {
                "identifiers": {(DOMAIN, self._entry.entry_id)},
                "name": "Olimex ESP32-C6",
                "manufacturer": "Olimex",
                "model": "ESP32-C6-EVB",
            }