"""Support for Amcrest IP cameras."""
import logging
from datetime import timedelta
import threading

import aiohttp
from amcrest import AmcrestError, Http, LoginError
import voluptuous as vol

from homeassistant.auth.permissions.const import POLICY_CONTROL
from homeassistant.components.binary_sensor import DOMAIN as BINARY_SENSOR
from homeassistant.components.camera import DOMAIN as CAMERA
from homeassistant.components.sensor import DOMAIN as SENSOR
from homeassistant.components.switch import DOMAIN as SWITCH
from homeassistant.const import (
    ATTR_ENTITY_ID, CONF_AUTHENTICATION, CONF_BINARY_SENSORS, CONF_HOST,
    CONF_NAME, CONF_PASSWORD, CONF_PORT, CONF_SCAN_INTERVAL, CONF_SENSORS,
    CONF_SWITCHES, CONF_USERNAME, ENTITY_MATCH_ALL, HTTP_BASIC_AUTHENTICATION)
from homeassistant.exceptions import Unauthorized, UnknownUser
from homeassistant.helpers import discovery
import homeassistant.helpers.config_validation as cv
from homeassistant.helpers.dispatcher import (
    async_dispatcher_send, dispatcher_send)
from homeassistant.helpers.event import track_time_interval
from homeassistant.helpers.service import async_extract_entity_ids

from .binary_sensor import BINARY_SENSOR_MOTION_DETECTED, BINARY_SENSORS
from .camera import CAMERA_SERVICES, STREAM_SOURCE_LIST
from .const import CAMERAS, DOMAIN, DATA_AMCREST, DEVICES, SERVICE_UPDATE
from .helpers import service_signal
from .sensor import SENSOR_MOTION_DETECTOR, SENSORS
from .switch import SWITCHES

_LOGGER = logging.getLogger(__name__)

CONF_RESOLUTION = 'resolution'
CONF_STREAM_SOURCE = 'stream_source'
CONF_FFMPEG_ARGUMENTS = 'ffmpeg_arguments'
CONF_CONTROL_LIGHT = 'control_light'

DEFAULT_NAME = 'Amcrest Camera'
DEFAULT_PORT = 80
DEFAULT_RESOLUTION = 'high'
DEFAULT_ARGUMENTS = '-pred 1'
MAX_ERRORS = 5
RECHECK_INTERVAL = timedelta(minutes=1)

NOTIFICATION_ID = 'amcrest_notification'
NOTIFICATION_TITLE = 'Amcrest Camera Setup'

RESOLUTION_LIST = {
    'high': 0,
    'low': 1,
}

SCAN_INTERVAL = timedelta(seconds=10)

AUTHENTICATION_LIST = {
    'basic': 'basic'
}


def _deprecated_sensor_values(sensors):
    if SENSOR_MOTION_DETECTOR in sensors:
        _LOGGER.warning(
            "The '%s' option value '%s' is deprecated, "
            "please remove it from your configuration and use "
            "the '%s' option with value '%s' instead",
            CONF_SENSORS, SENSOR_MOTION_DETECTOR, CONF_BINARY_SENSORS,
            BINARY_SENSOR_MOTION_DETECTED)
    return sensors


def _deprecated_switches(config):
    if CONF_SWITCHES in config:
        _LOGGER.warning(
            "The '%s' option (with value %s) is deprecated, "
            "please remove it from your configuration and use "
            "services and attributes instead",
            CONF_SWITCHES, config[CONF_SWITCHES])
    return config


def _has_unique_names(devices):
    names = [device[CONF_NAME] for device in devices]
    vol.Schema(vol.Unique())(names)
    return devices


AMCREST_SCHEMA = vol.All(
    vol.Schema({
        vol.Required(CONF_HOST): cv.string,
        vol.Required(CONF_USERNAME): cv.string,
        vol.Required(CONF_PASSWORD): cv.string,
        vol.Optional(CONF_NAME, default=DEFAULT_NAME): cv.string,
        vol.Optional(CONF_PORT, default=DEFAULT_PORT): cv.port,
        vol.Optional(CONF_AUTHENTICATION, default=HTTP_BASIC_AUTHENTICATION):
            vol.All(vol.In(AUTHENTICATION_LIST)),
        vol.Optional(CONF_RESOLUTION, default=DEFAULT_RESOLUTION):
            vol.All(vol.In(RESOLUTION_LIST)),
        vol.Optional(CONF_STREAM_SOURCE, default=STREAM_SOURCE_LIST[0]):
            vol.All(vol.In(STREAM_SOURCE_LIST)),
        vol.Optional(CONF_FFMPEG_ARGUMENTS, default=DEFAULT_ARGUMENTS):
            cv.string,
        vol.Optional(CONF_SCAN_INTERVAL, default=SCAN_INTERVAL):
            cv.time_period,
        vol.Optional(CONF_BINARY_SENSORS):
            vol.All(cv.ensure_list, [vol.In(BINARY_SENSORS)]),
        vol.Optional(CONF_SENSORS):
            vol.All(cv.ensure_list, [vol.In(SENSORS)],
                    _deprecated_sensor_values),
        vol.Optional(CONF_SWITCHES):
            vol.All(cv.ensure_list, [vol.In(SWITCHES)]),
        vol.Optional(CONF_CONTROL_LIGHT, default=True): cv.boolean,
    }),
    _deprecated_switches
)

CONFIG_SCHEMA = vol.Schema({
    DOMAIN: vol.All(cv.ensure_list, [AMCREST_SCHEMA], _has_unique_names)
}, extra=vol.ALLOW_EXTRA)


# pylint: disable=too-many-ancestors
class AmcrestChecker(Http):
    """amcrest.Http wrapper for catching errors."""

    def __init__(self, hass, name, host, port, user, password):
        """Initialize."""
        self._hass = hass
        self._wrap_name = name
        self._wrap_errors = 0
        self._wrap_lock = threading.Lock()
        self._unsub_recheck = None
        super().__init__(host, port, user, password, retries_connection=1,
                         timeout_protocol=3.05)

    @property
    def available(self):
        """Return if camera's API is responding."""
        return self._wrap_errors <= MAX_ERRORS

    def command(self, cmd, retries=None, timeout_cmd=None, stream=False):
        """amcrest.Http.command wrapper to catch errors."""
        try:
            ret = super().command(cmd, retries, timeout_cmd, stream)
        except AmcrestError:
            with self._wrap_lock:
                was_online = self.available
                self._wrap_errors += 1
                _LOGGER.debug('%s camera errs: %i', self._wrap_name,
                              self._wrap_errors)
                offline = not self.available
            if offline and was_online:
                _LOGGER.error(
                    '%s camera offline: Too many errors', self._wrap_name)
                dispatcher_send(
                    self._hass,
                    service_signal(SERVICE_UPDATE, self._wrap_name))
                self._unsub_recheck = track_time_interval(
                    self._hass, self._wrap_test_online, RECHECK_INTERVAL)
            raise
        with self._wrap_lock:
            was_offline = not self.available
            self._wrap_errors = 0
        if was_offline:
            self._unsub_recheck()
            self._unsub_recheck = None
            _LOGGER.error('%s camera back online', self._wrap_name)
            dispatcher_send(
                self._hass, service_signal(SERVICE_UPDATE, self._wrap_name))
        return ret

    def _wrap_test_online(self, now):
        """Test if camera is back online."""
        try:
            self.current_time
        except AmcrestError:
            pass


def setup(hass, config):
    """Set up the Amcrest IP Camera component."""
    hass.data.setdefault(DATA_AMCREST, {DEVICES: {}, CAMERAS: []})

    for device in config[DOMAIN]:
        name = device[CONF_NAME]
        username = device[CONF_USERNAME]
        password = device[CONF_PASSWORD]

        try:
            api = AmcrestChecker(
                hass, name,
                device[CONF_HOST], device[CONF_PORT],
                username, password)

        except LoginError as ex:
            _LOGGER.error("Login error for %s camera: %s", name, ex)
            continue

        ffmpeg_arguments = device[CONF_FFMPEG_ARGUMENTS]
        resolution = RESOLUTION_LIST[device[CONF_RESOLUTION]]
        binary_sensors = device.get(CONF_BINARY_SENSORS)
        sensors = device.get(CONF_SENSORS)
        switches = device.get(CONF_SWITCHES)
        stream_source = device[CONF_STREAM_SOURCE]
        control_light = device.get(CONF_CONTROL_LIGHT)

        # currently aiohttp only works with basic authentication
        # only valid for mjpeg streaming
        if device[CONF_AUTHENTICATION] == HTTP_BASIC_AUTHENTICATION:
            authentication = aiohttp.BasicAuth(username, password)
        else:
            authentication = None

        hass.data[DATA_AMCREST][DEVICES][name] = AmcrestDevice(
            api, authentication, ffmpeg_arguments, stream_source,
            resolution, control_light)

        discovery.load_platform(
            hass, CAMERA, DOMAIN, {
                CONF_NAME: name,
            }, config)

        if binary_sensors:
            discovery.load_platform(
                hass, BINARY_SENSOR, DOMAIN, {
                    CONF_NAME: name,
                    CONF_BINARY_SENSORS: binary_sensors
                }, config)

        if sensors:
            discovery.load_platform(
                hass, SENSOR, DOMAIN, {
                    CONF_NAME: name,
                    CONF_SENSORS: sensors,
                }, config)

        if switches:
            discovery.load_platform(
                hass, SWITCH, DOMAIN, {
                    CONF_NAME: name,
                    CONF_SWITCHES: switches
                }, config)

    if not hass.data[DATA_AMCREST][DEVICES]:
        return False

    def have_permission(user, entity_id):
        return not user or user.permissions.check_entity(
            entity_id, POLICY_CONTROL)

    async def async_extract_from_service(call):
        if call.context.user_id:
            user = await hass.auth.async_get_user(call.context.user_id)
            if user is None:
                raise UnknownUser(context=call.context)
        else:
            user = None

        if call.data.get(ATTR_ENTITY_ID) == ENTITY_MATCH_ALL:
            # Return all entity_ids user has permission to control.
            return [
                entity_id for entity_id in hass.data[DATA_AMCREST][CAMERAS]
                if have_permission(user, entity_id)
            ]

        call_ids = await async_extract_entity_ids(hass, call)
        entity_ids = []
        for entity_id in hass.data[DATA_AMCREST][CAMERAS]:
            if entity_id not in call_ids:
                continue
            if not have_permission(user, entity_id):
                raise Unauthorized(
                    context=call.context,
                    entity_id=entity_id,
                    permission=POLICY_CONTROL
                )
            entity_ids.append(entity_id)
        return entity_ids

    async def async_service_handler(call):
        args = []
        for arg in CAMERA_SERVICES[call.service][2]:
            args.append(call.data[arg])
        for entity_id in await async_extract_from_service(call):
            async_dispatcher_send(
                hass,
                service_signal(call.service, entity_id),
                *args
            )

    for service, params in CAMERA_SERVICES.items():
        hass.services.async_register(
            DOMAIN, service, async_service_handler, params[0])

    return True


class AmcrestDevice:
    """Representation of a base Amcrest discovery device."""

    def __init__(self, api, authentication, ffmpeg_arguments,
                 stream_source, resolution, control_light):
        """Initialize the entity."""
        self.api = api
        self.authentication = authentication
        self.ffmpeg_arguments = ffmpeg_arguments
        self.stream_source = stream_source
        self.resolution = resolution
        self.control_light = control_light