"""Provides functionality to interact with lights."""
import asyncio
import csv
from datetime import timedelta
import logging
import os
from typing import Dict, Optional, Tuple

import voluptuous as vol

from homeassistant.auth.permissions.const import POLICY_CONTROL
from homeassistant.const import (
    ATTR_ENTITY_ID,
    SERVICE_TOGGLE,
    SERVICE_TURN_OFF,
    SERVICE_TURN_ON,
    STATE_ON,
)
from homeassistant.exceptions import Unauthorized, UnknownUser
import homeassistant.helpers.config_validation as cv
from homeassistant.helpers.config_validation import (  # noqa: F401
    PLATFORM_SCHEMA,
    PLATFORM_SCHEMA_BASE,
    make_entity_service_schema,
)
from homeassistant.helpers.entity import ToggleEntity
from homeassistant.helpers.entity_component import EntityComponent
from homeassistant.loader import bind_hass
import homeassistant.util.color as color_util

# mypy: allow-untyped-defs, no-check-untyped-defs

DOMAIN = "light"
SCAN_INTERVAL = timedelta(seconds=30)

ENTITY_ID_FORMAT = DOMAIN + ".{}"

# Bitfield of features supported by the light entity
SUPPORT_BRIGHTNESS = 1
SUPPORT_COLOR_TEMP = 2
SUPPORT_EFFECT = 4
SUPPORT_FLASH = 8
SUPPORT_COLOR = 16
SUPPORT_TRANSITION = 32
SUPPORT_WHITE_VALUE = 128

# Integer that represents transition time in seconds to make change.
ATTR_TRANSITION = "transition"

# Lists holding color values
ATTR_RGB_COLOR = "rgb_color"
ATTR_XY_COLOR = "xy_color"
ATTR_HS_COLOR = "hs_color"
ATTR_COLOR_TEMP = "color_temp"
ATTR_KELVIN = "kelvin"
ATTR_MIN_MIREDS = "min_mireds"
ATTR_MAX_MIREDS = "max_mireds"
ATTR_COLOR_NAME = "color_name"
ATTR_WHITE_VALUE = "white_value"

# Brightness of the light, 0..255 or percentage
ATTR_BRIGHTNESS = "brightness"
ATTR_BRIGHTNESS_PCT = "brightness_pct"

# String representing a profile (built-in ones or external defined).
ATTR_PROFILE = "profile"

# If the light should flash, can be FLASH_SHORT or FLASH_LONG.
ATTR_FLASH = "flash"
FLASH_SHORT = "short"
FLASH_LONG = "long"

# List of possible effects
ATTR_EFFECT_LIST = "effect_list"

# Apply an effect to the light, can be EFFECT_COLORLOOP.
ATTR_EFFECT = "effect"
EFFECT_COLORLOOP = "colorloop"
EFFECT_RANDOM = "random"
EFFECT_WHITE = "white"

COLOR_GROUP = "Color descriptors"

LIGHT_PROFILES_FILE = "light_profiles.csv"

# Service call validation schemas
VALID_TRANSITION = vol.All(vol.Coerce(float), vol.Clamp(min=0, max=6553))
VALID_BRIGHTNESS = vol.All(vol.Coerce(int), vol.Clamp(min=0, max=255))
VALID_BRIGHTNESS_PCT = vol.All(vol.Coerce(float), vol.Range(min=0, max=100))

LIGHT_TURN_ON_SCHEMA = {
    vol.Exclusive(ATTR_PROFILE, COLOR_GROUP): cv.string,
    ATTR_TRANSITION: VALID_TRANSITION,
    ATTR_BRIGHTNESS: VALID_BRIGHTNESS,
    ATTR_BRIGHTNESS_PCT: VALID_BRIGHTNESS_PCT,
    vol.Exclusive(ATTR_COLOR_NAME, COLOR_GROUP): cv.string,
    vol.Exclusive(ATTR_RGB_COLOR, COLOR_GROUP): vol.All(
        vol.ExactSequence((cv.byte, cv.byte, cv.byte)), vol.Coerce(tuple)
    ),
    vol.Exclusive(ATTR_XY_COLOR, COLOR_GROUP): vol.All(
        vol.ExactSequence((cv.small_float, cv.small_float)), vol.Coerce(tuple)
    ),
    vol.Exclusive(ATTR_HS_COLOR, COLOR_GROUP): vol.All(
        vol.ExactSequence(
            (
                vol.All(vol.Coerce(float), vol.Range(min=0, max=360)),
                vol.All(vol.Coerce(float), vol.Range(min=0, max=100)),
            )
        ),
        vol.Coerce(tuple),
    ),
    vol.Exclusive(ATTR_COLOR_TEMP, COLOR_GROUP): vol.All(
        vol.Coerce(int), vol.Range(min=1)
    ),
    vol.Exclusive(ATTR_KELVIN, COLOR_GROUP): vol.All(vol.Coerce(int), vol.Range(min=0)),
    ATTR_WHITE_VALUE: vol.All(vol.Coerce(int), vol.Range(min=0, max=255)),
    ATTR_FLASH: vol.In([FLASH_SHORT, FLASH_LONG]),
    ATTR_EFFECT: cv.string,
}


PROFILE_SCHEMA = vol.Schema(
    vol.ExactSequence((str, cv.small_float, cv.small_float, cv.byte))
)

_LOGGER = logging.getLogger(__name__)


@bind_hass
def is_on(hass, entity_id):
    """Return if the lights are on based on the statemachine."""
    return hass.states.is_state(entity_id, STATE_ON)


def preprocess_turn_on_alternatives(params):
    """Process extra data for turn light on request."""
    profile = Profiles.get(params.pop(ATTR_PROFILE, None))
    if profile is not None:
        params.setdefault(ATTR_XY_COLOR, profile[:2])
        params.setdefault(ATTR_BRIGHTNESS, profile[2])

    color_name = params.pop(ATTR_COLOR_NAME, None)
    if color_name is not None:
        try:
            params[ATTR_RGB_COLOR] = color_util.color_name_to_rgb(color_name)
        except ValueError:
            _LOGGER.warning("Got unknown color %s, falling back to white", color_name)
            params[ATTR_RGB_COLOR] = (255, 255, 255)

    kelvin = params.pop(ATTR_KELVIN, None)
    if kelvin is not None:
        mired = color_util.color_temperature_kelvin_to_mired(kelvin)
        params[ATTR_COLOR_TEMP] = int(mired)

    brightness_pct = params.pop(ATTR_BRIGHTNESS_PCT, None)
    if brightness_pct is not None:
        params[ATTR_BRIGHTNESS] = int(255 * brightness_pct / 100)

    xy_color = params.pop(ATTR_XY_COLOR, None)
    if xy_color is not None:
        params[ATTR_HS_COLOR] = color_util.color_xy_to_hs(*xy_color)

    rgb_color = params.pop(ATTR_RGB_COLOR, None)
    if rgb_color is not None:
        params[ATTR_HS_COLOR] = color_util.color_RGB_to_hs(*rgb_color)


def preprocess_turn_off(params):
    """Process data for turning light off if brightness is 0."""
    if ATTR_BRIGHTNESS in params and params[ATTR_BRIGHTNESS] == 0:
        # Zero brightness: Light will be turned off
        params = {k: v for k, v in params.items() if k in [ATTR_TRANSITION, ATTR_FLASH]}
        return (True, params)  # Light should be turned off

    return (False, None)  # Light should be turned on


async def async_setup(hass, config):
    """Expose light control via state machine and services."""
    component = hass.data[DOMAIN] = EntityComponent(
        _LOGGER, DOMAIN, hass, SCAN_INTERVAL
    )
    await component.async_setup(config)

    # load profiles from files
    profiles_valid = await Profiles.load_profiles(hass)
    if not profiles_valid:
        return False

    async def async_handle_light_on_service(service):
        """Handle a turn light on service call."""
        # Get the validated data
        params = service.data.copy()

        # Convert the entity ids to valid light ids
        target_lights = await component.async_extract_from_service(service)
        params.pop(ATTR_ENTITY_ID, None)

        if service.context.user_id:
            user = await hass.auth.async_get_user(service.context.user_id)
            if user is None:
                raise UnknownUser(context=service.context)

            entity_perms = user.permissions.check_entity

            for light in target_lights:
                if not entity_perms(light, POLICY_CONTROL):
                    raise Unauthorized(
                        context=service.context,
                        entity_id=light,
                        permission=POLICY_CONTROL,
                    )

        preprocess_turn_on_alternatives(params)
        turn_lights_off, off_params = preprocess_turn_off(params)

        poll_lights = []
        change_tasks = []
        for light in target_lights:
            light.async_set_context(service.context)

            pars = params
            off_pars = off_params
            turn_light_off = turn_lights_off
            if not pars:
                pars = params.copy()
                pars[ATTR_PROFILE] = Profiles.get_default(light.entity_id)
                preprocess_turn_on_alternatives(pars)
                turn_light_off, off_pars = preprocess_turn_off(pars)
            if turn_light_off:
                task = light.async_request_call(light.async_turn_off(**off_pars))
            else:
                task = light.async_request_call(light.async_turn_on(**pars))

            change_tasks.append(task)

            if light.should_poll:
                poll_lights.append(light)

        if change_tasks:
            await asyncio.wait(change_tasks)

        if poll_lights:
            await asyncio.wait(
                [light.async_update_ha_state(True) for light in poll_lights]
            )

    # Listen for light on and light off service calls.
    hass.services.async_register(
        DOMAIN,
        SERVICE_TURN_ON,
        async_handle_light_on_service,
        schema=cv.make_entity_service_schema(LIGHT_TURN_ON_SCHEMA),
    )

    component.async_register_entity_service(
        SERVICE_TURN_OFF,
        {
            ATTR_TRANSITION: VALID_TRANSITION,
            ATTR_FLASH: vol.In([FLASH_SHORT, FLASH_LONG]),
        },
        "async_turn_off",
    )

    component.async_register_entity_service(
        SERVICE_TOGGLE, LIGHT_TURN_ON_SCHEMA, "async_toggle"
    )

    return True


async def async_setup_entry(hass, entry):
    """Set up a config entry."""
    return await hass.data[DOMAIN].async_setup_entry(entry)


async def async_unload_entry(hass, entry):
    """Unload a config entry."""
    return await hass.data[DOMAIN].async_unload_entry(entry)


class Profiles:
    """Representation of available color profiles."""

    _all: Optional[Dict[str, Tuple[float, float, int]]] = None

    @classmethod
    async def load_profiles(cls, hass):
        """Load and cache profiles."""

        def load_profile_data(hass):
            """Load built-in profiles and custom profiles."""
            profile_paths = [
                os.path.join(os.path.dirname(__file__), LIGHT_PROFILES_FILE),
                hass.config.path(LIGHT_PROFILES_FILE),
            ]
            profiles = {}

            for profile_path in profile_paths:
                if not os.path.isfile(profile_path):
                    continue
                with open(profile_path) as inp:
                    reader = csv.reader(inp)

                    # Skip the header
                    next(reader, None)

                    try:
                        for rec in reader:
                            profile, color_x, color_y, brightness = PROFILE_SCHEMA(rec)
                            profiles[profile] = (color_x, color_y, brightness)
                    except vol.MultipleInvalid as ex:
                        _LOGGER.error(
                            "Error parsing light profile from %s: %s", profile_path, ex
                        )
                        return None
            return profiles

        cls._all = await hass.async_add_job(load_profile_data, hass)
        return cls._all is not None

    @classmethod
    def get(cls, name):
        """Return a named profile."""
        return cls._all.get(name)

    @classmethod
    def get_default(cls, entity_id):
        """Return the default turn-on profile for the given light."""
        # pylint: disable=unsupported-membership-test
        name = entity_id + ".default"
        if name in cls._all:
            return name
        name = "group.all_lights.default"
        if name in cls._all:
            return name
        return None


class Light(ToggleEntity):
    """Representation of a light."""

    @property
    def brightness(self):
        """Return the brightness of this light between 0..255."""
        return None

    @property
    def hs_color(self):
        """Return the hue and saturation color value [float, float]."""
        return None

    @property
    def color_temp(self):
        """Return the CT color value in mireds."""
        return None

    @property
    def min_mireds(self):
        """Return the coldest color_temp that this light supports."""
        # Default to the Philips Hue value that HA has always assumed
        # https://developers.meethue.com/documentation/core-concepts
        return 153

    @property
    def max_mireds(self):
        """Return the warmest color_temp that this light supports."""
        # Default to the Philips Hue value that HA has always assumed
        # https://developers.meethue.com/documentation/core-concepts
        return 500

    @property
    def white_value(self):
        """Return the white value of this light between 0..255."""
        return None

    @property
    def effect_list(self):
        """Return the list of supported effects."""
        return None

    @property
    def effect(self):
        """Return the current effect."""
        return None

    @property
    def capability_attributes(self):
        """Return capability attributes."""
        data = {}
        supported_features = self.supported_features

        if supported_features & SUPPORT_COLOR_TEMP:
            data[ATTR_MIN_MIREDS] = self.min_mireds
            data[ATTR_MAX_MIREDS] = self.max_mireds

        if supported_features & SUPPORT_EFFECT:
            data[ATTR_EFFECT_LIST] = self.effect_list

        return data

    @property
    def state_attributes(self):
        """Return state attributes."""
        if not self.is_on:
            return None

        data = {}
        supported_features = self.supported_features

        if supported_features & SUPPORT_BRIGHTNESS:
            data[ATTR_BRIGHTNESS] = self.brightness

        if supported_features & SUPPORT_COLOR_TEMP:
            data[ATTR_COLOR_TEMP] = self.color_temp

        if supported_features & SUPPORT_COLOR and self.hs_color:
            # pylint: disable=unsubscriptable-object,not-an-iterable
            hs_color = self.hs_color
            data[ATTR_HS_COLOR] = (round(hs_color[0], 3), round(hs_color[1], 3))
            data[ATTR_RGB_COLOR] = color_util.color_hs_to_RGB(*hs_color)
            data[ATTR_XY_COLOR] = color_util.color_hs_to_xy(*hs_color)

        if supported_features & SUPPORT_WHITE_VALUE:
            data[ATTR_WHITE_VALUE] = self.white_value

        if supported_features & SUPPORT_EFFECT:
            data[ATTR_EFFECT] = self.effect

        return {key: val for key, val in data.items() if val is not None}

    @property
    def supported_features(self):
        """Flag supported features."""
        return 0