"""The airvisual component."""
import asyncio
from datetime import timedelta
from math import ceil

from pyairvisual import CloudAPI, NodeSamba
from pyairvisual.errors import (
    AirVisualError,
    InvalidKeyError,
    KeyExpiredError,
    NodeProError,
)

from homeassistant.config_entries import SOURCE_REAUTH
from homeassistant.const import (
    ATTR_ATTRIBUTION,
    CONF_API_KEY,
    CONF_IP_ADDRESS,
    CONF_LATITUDE,
    CONF_LONGITUDE,
    CONF_PASSWORD,
    CONF_SHOW_ON_MAP,
    CONF_STATE,
)
from homeassistant.core import callback
from homeassistant.exceptions import ConfigEntryNotReady
from homeassistant.helpers import aiohttp_client, config_validation as cv
from homeassistant.helpers.update_coordinator import (
    CoordinatorEntity,
    DataUpdateCoordinator,
    UpdateFailed,
)

from .const import (
    CONF_CITY,
    CONF_COUNTRY,
    CONF_GEOGRAPHIES,
    CONF_INTEGRATION_TYPE,
    DATA_COORDINATOR,
    DOMAIN,
    INTEGRATION_TYPE_GEOGRAPHY_COORDS,
    INTEGRATION_TYPE_GEOGRAPHY_NAME,
    INTEGRATION_TYPE_NODE_PRO,
    LOGGER,
)

PLATFORMS = ["air_quality", "sensor"]

DATA_LISTENER = "listener"

DEFAULT_ATTRIBUTION = "Data provided by AirVisual"
DEFAULT_NODE_PRO_UPDATE_INTERVAL = timedelta(minutes=1)

CONFIG_SCHEMA = cv.deprecated(DOMAIN)


@callback
def async_get_geography_id(geography_dict):
    """Generate a unique ID from a geography dict."""
    if not geography_dict:
        return

    if CONF_CITY in geography_dict:
        return ", ".join(
            (
                geography_dict[CONF_CITY],
                geography_dict[CONF_STATE],
                geography_dict[CONF_COUNTRY],
            )
        )
    return ", ".join(
        (str(geography_dict[CONF_LATITUDE]), str(geography_dict[CONF_LONGITUDE]))
    )


@callback
def async_get_cloud_api_update_interval(hass, api_key, num_consumers):
    """Get a leveled scan interval for a particular cloud API key.

    This will shift based on the number of active consumers, thus keeping the user
    under the monthly API limit.
    """
    # Assuming 10,000 calls per month and a "smallest possible month" of 28 days; note
    # that we give a buffer of 1500 API calls for any drift, restarts, etc.:
    minutes_between_api_calls = ceil(1 / (8500 / 28 / 24 / 60 / num_consumers))

    LOGGER.debug(
        "Leveling API key usage (%s): %s consumers, %s minutes between updates",
        api_key,
        num_consumers,
        minutes_between_api_calls,
    )

    return timedelta(minutes=minutes_between_api_calls)


@callback
def async_get_cloud_coordinators_by_api_key(hass, api_key):
    """Get all DataUpdateCoordinator objects related to a particular API key."""
    coordinators = []
    for entry_id, coordinator in hass.data[DOMAIN][DATA_COORDINATOR].items():
        config_entry = hass.config_entries.async_get_entry(entry_id)
        if config_entry.data.get(CONF_API_KEY) == api_key:
            coordinators.append(coordinator)
    return coordinators


@callback
def async_sync_geo_coordinator_update_intervals(hass, api_key):
    """Sync the update interval for geography-based data coordinators (by API key)."""
    coordinators = async_get_cloud_coordinators_by_api_key(hass, api_key)

    if not coordinators:
        return

    update_interval = async_get_cloud_api_update_interval(
        hass, api_key, len(coordinators)
    )

    for coordinator in coordinators:
        LOGGER.debug(
            "Updating interval for coordinator: %s, %s",
            coordinator.name,
            update_interval,
        )
        coordinator.update_interval = update_interval


async def async_setup(hass, config):
    """Set up the AirVisual component."""
    hass.data[DOMAIN] = {DATA_COORDINATOR: {}, DATA_LISTENER: {}}
    return True


@callback
def _standardize_geography_config_entry(hass, config_entry):
    """Ensure that geography config entries have appropriate properties."""
    entry_updates = {}

    if not config_entry.unique_id:
        # If the config entry doesn't already have a unique ID, set one:
        entry_updates["unique_id"] = config_entry.data[CONF_API_KEY]
    if not config_entry.options:
        # If the config entry doesn't already have any options set, set defaults:
        entry_updates["options"] = {CONF_SHOW_ON_MAP: True}
    if config_entry.data.get(CONF_INTEGRATION_TYPE) not in [
        INTEGRATION_TYPE_GEOGRAPHY_COORDS,
        INTEGRATION_TYPE_GEOGRAPHY_NAME,
    ]:
        # If the config entry data doesn't contain an integration type that we know
        # about, infer it from the data we have:
        entry_updates["data"] = {**config_entry.data}
        if CONF_CITY in config_entry.data:
            entry_updates["data"][
                CONF_INTEGRATION_TYPE
            ] = INTEGRATION_TYPE_GEOGRAPHY_NAME
        else:
            entry_updates["data"][
                CONF_INTEGRATION_TYPE
            ] = INTEGRATION_TYPE_GEOGRAPHY_COORDS

    if not entry_updates:
        return

    hass.config_entries.async_update_entry(config_entry, **entry_updates)


@callback
def _standardize_node_pro_config_entry(hass, config_entry):
    """Ensure that Node/Pro config entries have appropriate properties."""
    entry_updates = {}

    if CONF_INTEGRATION_TYPE not in config_entry.data:
        # If the config entry data doesn't contain the integration type, add it:
        entry_updates["data"] = {
            **config_entry.data,
            CONF_INTEGRATION_TYPE: INTEGRATION_TYPE_NODE_PRO,
        }

    if not entry_updates:
        return

    hass.config_entries.async_update_entry(config_entry, **entry_updates)


async def async_setup_entry(hass, config_entry):
    """Set up AirVisual as config entry."""
    if CONF_API_KEY in config_entry.data:
        _standardize_geography_config_entry(hass, config_entry)

        websession = aiohttp_client.async_get_clientsession(hass)
        cloud_api = CloudAPI(config_entry.data[CONF_API_KEY], session=websession)

        async def async_update_data():
            """Get new data from the API."""
            if CONF_CITY in config_entry.data:
                api_coro = cloud_api.air_quality.city(
                    config_entry.data[CONF_CITY],
                    config_entry.data[CONF_STATE],
                    config_entry.data[CONF_COUNTRY],
                )
            else:
                api_coro = cloud_api.air_quality.nearest_city(
                    config_entry.data[CONF_LATITUDE],
                    config_entry.data[CONF_LONGITUDE],
                )

            try:
                return await api_coro
            except (InvalidKeyError, KeyExpiredError):
                matching_flows = [
                    flow
                    for flow in hass.config_entries.flow.async_progress()
                    if flow["context"]["source"] == SOURCE_REAUTH
                    and flow["context"]["unique_id"] == config_entry.unique_id
                ]

                if not matching_flows:
                    hass.async_create_task(
                        hass.config_entries.flow.async_init(
                            DOMAIN,
                            context={
                                "source": SOURCE_REAUTH,
                                "unique_id": config_entry.unique_id,
                            },
                            data=config_entry.data,
                        )
                    )

                return {}
            except AirVisualError as err:
                raise UpdateFailed(f"Error while retrieving data: {err}") from err

        coordinator = DataUpdateCoordinator(
            hass,
            LOGGER,
            name=async_get_geography_id(config_entry.data),
            # We give a placeholder update interval in order to create the coordinator;
            # then, below, we use the coordinator's presence (along with any other
            # coordinators using the same API key) to calculate an actual, leveled
            # update interval:
            update_interval=timedelta(minutes=5),
            update_method=async_update_data,
        )

        async_sync_geo_coordinator_update_intervals(
            hass, config_entry.data[CONF_API_KEY]
        )

        # Only geography-based entries have options:
        hass.data[DOMAIN][DATA_LISTENER][
            config_entry.entry_id
        ] = config_entry.add_update_listener(async_reload_entry)
    else:
        _standardize_node_pro_config_entry(hass, config_entry)

        async def async_update_data():
            """Get new data from the API."""
            try:
                async with NodeSamba(
                    config_entry.data[CONF_IP_ADDRESS], config_entry.data[CONF_PASSWORD]
                ) as node:
                    return await node.async_get_latest_measurements()
            except NodeProError as err:
                raise UpdateFailed(f"Error while retrieving data: {err}") from err

        coordinator = DataUpdateCoordinator(
            hass,
            LOGGER,
            name="Node/Pro data",
            update_interval=DEFAULT_NODE_PRO_UPDATE_INTERVAL,
            update_method=async_update_data,
        )

    await coordinator.async_refresh()
    if not coordinator.last_update_success:
        raise ConfigEntryNotReady

    hass.data[DOMAIN][DATA_COORDINATOR][config_entry.entry_id] = coordinator

    for platform in PLATFORMS:
        hass.async_create_task(
            hass.config_entries.async_forward_entry_setup(config_entry, platform)
        )

    return True


async def async_migrate_entry(hass, config_entry):
    """Migrate an old config entry."""
    version = config_entry.version

    LOGGER.debug("Migrating from version %s", version)

    # 1 -> 2: One geography per config entry
    if version == 1:
        version = config_entry.version = 2

        # Update the config entry to only include the first geography (there is always
        # guaranteed to be at least one):
        geographies = list(config_entry.data[CONF_GEOGRAPHIES])
        first_geography = geographies.pop(0)
        first_id = async_get_geography_id(first_geography)

        hass.config_entries.async_update_entry(
            config_entry,
            unique_id=first_id,
            title=f"Cloud API ({first_id})",
            data={CONF_API_KEY: config_entry.data[CONF_API_KEY], **first_geography},
        )

        # For any geographies that remain, create a new config entry for each one:
        for geography in geographies:
            if CONF_LATITUDE in geography:
                source = "geography_by_coords"
            else:
                source = "geography_by_name"
            hass.async_create_task(
                hass.config_entries.flow.async_init(
                    DOMAIN,
                    context={"source": source},
                    data={CONF_API_KEY: config_entry.data[CONF_API_KEY], **geography},
                )
            )

    LOGGER.info("Migration to version %s successful", version)

    return True


async def async_unload_entry(hass, config_entry):
    """Unload an AirVisual config entry."""
    unload_ok = all(
        await asyncio.gather(
            *[
                hass.config_entries.async_forward_entry_unload(config_entry, platform)
                for platform in PLATFORMS
            ]
        )
    )
    if unload_ok:
        hass.data[DOMAIN][DATA_COORDINATOR].pop(config_entry.entry_id)
        remove_listener = hass.data[DOMAIN][DATA_LISTENER].pop(config_entry.entry_id)
        remove_listener()

        if (
            config_entry.data[CONF_INTEGRATION_TYPE]
            == INTEGRATION_TYPE_GEOGRAPHY_COORDS
        ):
            # Re-calculate the update interval period for any remaining consumers of
            # this API key:
            async_sync_geo_coordinator_update_intervals(
                hass, config_entry.data[CONF_API_KEY]
            )

    return unload_ok


async def async_reload_entry(hass, config_entry):
    """Handle an options update."""
    await hass.config_entries.async_reload(config_entry.entry_id)


class AirVisualEntity(CoordinatorEntity):
    """Define a generic AirVisual entity."""

    def __init__(self, coordinator):
        """Initialize."""
        super().__init__(coordinator)
        self._attrs = {ATTR_ATTRIBUTION: DEFAULT_ATTRIBUTION}
        self._icon = None
        self._unit = None

    @property
    def device_state_attributes(self):
        """Return the device state attributes."""
        return self._attrs

    @property
    def icon(self):
        """Return the icon."""
        return self._icon

    @property
    def unit_of_measurement(self):
        """Return the unit the value is expressed in."""
        return self._unit

    async def async_added_to_hass(self):
        """Register callbacks."""

        @callback
        def update():
            """Update the state."""
            self.update_from_latest_data()
            self.async_write_ha_state()

        self.async_on_remove(self.coordinator.async_add_listener(update))

        self.update_from_latest_data()

    @callback
    def update_from_latest_data(self):
        """Update the entity from the latest data."""
        raise NotImplementedError