"""Various helpers to handle config entry and api schema migrations."""

import logging

from aiohue import HueBridgeV2
from aiohue.discovery import is_v2_bridge
from aiohue.v2.models.device import DeviceArchetypes
from aiohue.v2.models.resource import ResourceTypes

from homeassistant import core
from homeassistant.components.binary_sensor import BinarySensorDeviceClass
from homeassistant.components.sensor import SensorDeviceClass
from homeassistant.config_entries import ConfigEntry
from homeassistant.const import CONF_API_KEY, CONF_HOST, CONF_USERNAME
from homeassistant.helpers import aiohttp_client
from homeassistant.helpers.device_registry import (
    async_entries_for_config_entry as devices_for_config_entries,
    async_get as async_get_device_registry,
)
from homeassistant.helpers.entity_registry import (
    async_entries_for_config_entry as entities_for_config_entry,
    async_entries_for_device,
    async_get as async_get_entity_registry,
)

from .const import CONF_API_VERSION, DOMAIN

LOGGER = logging.getLogger(__name__)


async def check_migration(hass: core.HomeAssistant, entry: ConfigEntry) -> None:
    """Check if config entry needs any migration actions."""
    host = entry.data[CONF_HOST]

    # migrate CONF_USERNAME --> CONF_API_KEY
    if CONF_USERNAME in entry.data:
        LOGGER.info("Migrate %s to %s in schema", CONF_USERNAME, CONF_API_KEY)
        data = dict(entry.data)
        data[CONF_API_KEY] = data.pop(CONF_USERNAME)
        hass.config_entries.async_update_entry(entry, data=data)

    conf_api_version = entry.data.get(CONF_API_VERSION, 1)
    if conf_api_version == 1:
        # a bridge might have upgraded firmware since last run so
        # we discover its capabilities at every startup
        websession = aiohttp_client.async_get_clientsession(hass)
        if await is_v2_bridge(host, websession):
            supported_api_version = 2
        else:
            supported_api_version = 1
        LOGGER.debug(
            "Configured api version is %s and supported api version %s for bridge %s",
            conf_api_version,
            supported_api_version,
            host,
        )

        # the call to `is_v2_bridge` returns (silently) False even on connection error
        # so if a migration is needed it will be done on next startup

        if conf_api_version == 1 and supported_api_version == 2:
            # run entity/device schema migration for v2
            await handle_v2_migration(hass, entry)

        # store api version in entry data
        if (
            CONF_API_VERSION not in entry.data
            or conf_api_version != supported_api_version
        ):
            data = dict(entry.data)
            data[CONF_API_VERSION] = supported_api_version
            hass.config_entries.async_update_entry(entry, data=data)


async def handle_v2_migration(hass: core.HomeAssistant, entry: ConfigEntry) -> None:
    """Perform migration of devices and entities to V2 Id's."""
    host = entry.data[CONF_HOST]
    api_key = entry.data[CONF_API_KEY]
    dev_reg = async_get_device_registry(hass)
    ent_reg = async_get_entity_registry(hass)
    LOGGER.info("Start of migration of devices and entities to support API schema 2")

    # Create mapping of mac address to HA device id's.
    # Identifier in dev reg should be mac-address,
    # but in some cases it has a postfix like `-0b` or `-01`.
    dev_ids = {}
    for hass_dev in devices_for_config_entries(dev_reg, entry.entry_id):
        for domain, mac in hass_dev.identifiers:
            if domain != DOMAIN:
                continue
            normalized_mac = mac.split("-")[0]
            dev_ids[normalized_mac] = hass_dev.id

    # initialize bridge connection just for the migration
    async with HueBridgeV2(host, api_key) as api:

        sensor_class_mapping = {
            SensorDeviceClass.BATTERY.value: ResourceTypes.DEVICE_POWER,
            BinarySensorDeviceClass.MOTION.value: ResourceTypes.MOTION,
            SensorDeviceClass.ILLUMINANCE.value: ResourceTypes.LIGHT_LEVEL,
            SensorDeviceClass.TEMPERATURE.value: ResourceTypes.TEMPERATURE,
        }

        # migrate entities attached to a device
        for hue_dev in api.devices:
            zigbee = api.devices.get_zigbee_connectivity(hue_dev.id)
            if not zigbee or not zigbee.mac_address:
                # not a zigbee device or invalid mac
                continue

            # get existing device by V1 identifier (mac address)
            if hue_dev.product_data.product_archetype == DeviceArchetypes.BRIDGE_V2:
                hass_dev_id = dev_ids.get(api.config.bridge_id.upper())
            else:
                hass_dev_id = dev_ids.get(zigbee.mac_address)
            if hass_dev_id is None:
                # can be safely ignored, this device does not exist in current config
                LOGGER.debug(
                    "Ignoring device %s (%s) as it does not (yet) exist in the device registry",
                    hue_dev.metadata.name,
                    hue_dev.id,
                )
                continue
            dev_reg.async_update_device(
                hass_dev_id, new_identifiers={(DOMAIN, hue_dev.id)}
            )
            LOGGER.info("Migrated device %s (%s)", hue_dev.metadata.name, hass_dev_id)

            # loop through all entities for device and find match
            for ent in async_entries_for_device(ent_reg, hass_dev_id, True):

                if ent.entity_id.startswith("light"):
                    # migrate light
                    # should always return one lightid here
                    new_unique_id = next(iter(hue_dev.lights), None)
                else:
                    # migrate sensors
                    matched_dev_class = sensor_class_mapping.get(
                        ent.original_device_class or "unknown"
                    )
                    new_unique_id = next(
                        (
                            sensor.id
                            for sensor in api.devices.get_sensors(hue_dev.id)
                            if sensor.type == matched_dev_class
                        ),
                        None,
                    )

                if new_unique_id is None:
                    # this may happen if we're looking at orphaned or unsupported entity
                    LOGGER.warning(
                        "Skip migration of %s because it no longer exists on the bridge",
                        ent.entity_id,
                    )
                    continue

                try:
                    ent_reg.async_update_entity(
                        ent.entity_id, new_unique_id=new_unique_id
                    )
                except ValueError:
                    # assume edge case where the entity was already migrated in a previous run
                    # which got aborted somehow and we do not want
                    # to crash the entire integration init
                    LOGGER.warning(
                        "Skip migration of %s because it already exists",
                        ent.entity_id,
                    )
                else:
                    LOGGER.info(
                        "Migrated entity %s from unique id %s to %s",
                        ent.entity_id,
                        ent.unique_id,
                        new_unique_id,
                    )

        # migrate entities that are not connected to a device (groups)
        for ent in entities_for_config_entry(ent_reg, entry.entry_id):
            if ent.device_id is not None:
                continue
            if "-" in ent.unique_id:
                # handle case where unique id is v2-id of group/zone
                hue_group = api.groups.get(ent.unique_id)
            else:
                # handle case where the unique id is just the v1 id
                v1_id = f"/groups/{ent.unique_id}"
                hue_group = api.groups.room.get_by_v1_id(
                    v1_id
                ) or api.groups.zone.get_by_v1_id(v1_id)
            if hue_group is None or hue_group.grouped_light is None:
                # this may happen if we're looking at some orphaned entity
                LOGGER.warning(
                    "Skip migration of %s because it no longer exist on the bridge",
                    ent.entity_id,
                )
                continue
            new_unique_id = hue_group.grouped_light
            LOGGER.info(
                "Migrating %s from unique id %s to %s ",
                ent.entity_id,
                ent.unique_id,
                new_unique_id,
            )
            try:
                ent_reg.async_update_entity(ent.entity_id, new_unique_id=new_unique_id)
            except ValueError:
                # assume edge case where the entity was already migrated in a previous run
                # which got aborted somehow and we do not want
                # to crash the entire integration init
                LOGGER.warning(
                    "Skip migration of %s because it already exists",
                    ent.entity_id,
                )
    LOGGER.info("Migration of devices and entities to support API schema 2 finished")
