"""Platform to retrieve uptime for Home Assistant."""
from __future__ import annotations

import voluptuous as vol

from homeassistant.components.sensor import (
    PLATFORM_SCHEMA,
    SensorDeviceClass,
    SensorEntity,
)
from homeassistant.config_entries import SOURCE_IMPORT, ConfigEntry
from homeassistant.const import CONF_NAME, CONF_UNIT_OF_MEASUREMENT
from homeassistant.core import HomeAssistant
import homeassistant.helpers.config_validation as cv
from homeassistant.helpers.entity_platform import AddEntitiesCallback
from homeassistant.helpers.typing import ConfigType, DiscoveryInfoType
import homeassistant.util.dt as dt_util

from .const import DEFAULT_NAME, DOMAIN

PLATFORM_SCHEMA = vol.All(
    cv.removed(CONF_UNIT_OF_MEASUREMENT, raise_if_present=False),
    PLATFORM_SCHEMA.extend(
        {
            vol.Optional(CONF_NAME, default=DEFAULT_NAME): cv.string,
            vol.Remove(CONF_UNIT_OF_MEASUREMENT): cv.string,
        },
    ),
)


async def async_setup_platform(
    hass: HomeAssistant,
    config: ConfigType,
    async_add_entities: AddEntitiesCallback,
    discovery_info: DiscoveryInfoType | None = None,
) -> None:
    """Set up the uptime sensor platform."""
    hass.async_create_task(
        hass.config_entries.flow.async_init(
            DOMAIN,
            context={"source": SOURCE_IMPORT},
            data=config,
        )
    )


async def async_setup_entry(
    hass: HomeAssistant,
    entry: ConfigEntry,
    async_add_entities: AddEntitiesCallback,
) -> None:
    """Set up the platform from config_entry."""
    async_add_entities([UptimeSensor(entry)])


class UptimeSensor(SensorEntity):
    """Representation of an uptime sensor."""

    _attr_device_class = SensorDeviceClass.TIMESTAMP
    _attr_should_poll = False

    def __init__(self, entry: ConfigEntry) -> None:
        """Initialize the uptime sensor."""
        self._attr_name = entry.title
        self._attr_native_value = dt_util.utcnow()
        self._attr_unique_id = entry.entry_id