"""
Support for Dovado router.

For more details about this platform, please refer to the documentation at
https://home-assistant.io/components/sensor.dovado/
"""
import logging
import re
from datetime import timedelta

import voluptuous as vol

from homeassistant.helpers.entity import Entity
from homeassistant.util import Throttle
from homeassistant.util import slugify
import homeassistant.helpers.config_validation as cv
from homeassistant.const import (CONF_USERNAME, CONF_PASSWORD,
                                 CONF_HOST, CONF_PORT,
                                 CONF_SENSORS, STATE_UNKNOWN)
from homeassistant.components.sensor import (DOMAIN, PLATFORM_SCHEMA)

_LOGGER = logging.getLogger(__name__)

REQUIREMENTS = ['dovado==0.1.15']

MIN_TIME_BETWEEN_UPDATES = timedelta(seconds=30)

SENSOR_UPLOAD = "upload"
SENSOR_DOWNLOAD = "download"
SENSOR_SIGNAL = "signal"
SENSOR_NETWORK = "network"
SENSOR_SMS_UNREAD = "sms"

SENSORS = {
    SENSOR_NETWORK: ("signal strength", "Network", None,
                     "mdi:access-point-network"),
    SENSOR_SIGNAL: ("signal strength", "Signal Strength", "%",
                    "mdi:signal"),
    SENSOR_SMS_UNREAD: ("sms unread", "SMS unread", "",
                        "mdi:message-text-outline"),
    SENSOR_UPLOAD: ("traffic modem tx", "Sent", "GiB",
                    "mdi:cloud-upload"),
    SENSOR_DOWNLOAD: ("traffic modem rx", "Received", "GiB",
                      "mdi:cloud-download"),
}

PLATFORM_SCHEMA = PLATFORM_SCHEMA.extend({
    vol.Required(CONF_USERNAME): cv.string,
    vol.Required(CONF_PASSWORD): cv.string,
    vol.Optional(CONF_HOST): cv.string,
    vol.Optional(CONF_PORT): cv.port,
    vol.Optional(CONF_SENSORS):
    vol.All(cv.ensure_list, [vol.In(SENSORS)]),
})


def setup_platform(hass, config, add_devices, discovery_info=None):
    """Setup the dovado platform for sensors."""
    return Dovado().setup(hass, config, add_devices)


class Dovado:
    """A connection to the router."""

    def __init__(self):
        """Initialize."""
        self.state = {}
        self._dovado = None

    def setup(self, hass, config, add_devices):
        """Setup the connection."""
        import dovado
        self._dovado = dovado.Dovado(
            config.get(CONF_USERNAME),
            config.get(CONF_PASSWORD),
            config.get(CONF_HOST),
            config.get(CONF_PORT))

        if not self.update():
            return False

        def send_sms(service):
            """Send SMS through the router."""
            number = service.data.get("number"),
            message = service.data.get("message")
            _LOGGER.debug("message for %s: %s",
                          number, message)
            self._dovado.send_sms(number, message)

        if self.state["sms"] == "enabled":
            service_name = slugify("{} {}".format(self.name,
                                                  "send_sms"))
            hass.services.register(DOMAIN, service_name, send_sms)

        for sensor in SENSORS:
            if sensor in config.get(CONF_SENSORS, [sensor]):
                add_devices([DovadoSensor(self, sensor)])

        return True

    @property
    def name(self):
        """Name of the router."""
        return self.state["product name"]

    @Throttle(MIN_TIME_BETWEEN_UPDATES)
    def update(self):
        """Update device state."""
        _LOGGER.info("Updating")
        try:
            self.state = self._dovado.query_state()
            self.state.update(
                connected=self.state["modem status"] == "CONNECTED")
            _LOGGER.debug("Received: %s", self.state)
            return True
        except OSError as error:
            _LOGGER.error("Could not contact the router: %s", error)
            return False


class DovadoSensor(Entity):
    """Representation of a Dovado sensor."""

    def __init__(self, dovado, sensor):
        """Initialize the sensor."""
        self._dovado = dovado
        self._sensor = sensor

    def update(self):
        """Update sensor values."""
        self._dovado.update()

    @property
    def name(self):
        """Return the name of the sensor."""
        return "{} {}".format(self._dovado.name,
                              SENSORS[self._sensor][1])

    @property
    def state(self):
        """Return the sensor state."""
        key = SENSORS[self._sensor][0]
        result = self._dovado.state[key]
        if self._sensor == SENSOR_NETWORK:
            match = re.search(r"\((.+)\)", result)
            return match.group(1) if match else STATE_UNKNOWN
        elif self._sensor == SENSOR_SIGNAL:
            try:
                return int(result.split()[0])
            except ValueError:
                return 0
        elif self._sensor == SENSOR_SMS_UNREAD:
            return int(result)
        elif self._sensor in [SENSOR_UPLOAD, SENSOR_DOWNLOAD]:
            gib = pow(2, 30)
            return round(int(result) / gib, 1)
        else:
            return result

    @property
    def icon(self):
        """Return the icon for the sensor."""
        return SENSORS[self._sensor][3]

    @property
    def unit_of_measurement(self):
        """Return the unit of measurement."""
        return SENSORS[self._sensor][2]

    @property
    def device_state_attributes(self):
        """Return the state attributes."""
        return {k: v for k, v in self._dovado.state.items()
                if k not in ["date", "time"]}