text: """
  Support for WeMo switches.
  
  For more details about this component, please refer to the documentation at
  https://home-assistant.io/components/switch.wemo/
  """
  import asyncio
  import logging
  from datetime import datetime, timedelta
  
  import async_timeout
  
  from homeassistant.components.switch import SwitchDevice
  from homeassistant.util import convert
  from homeassistant.const import (
      STATE_OFF, STATE_ON, STATE_STANDBY, STATE_UNKNOWN)
  
  DEPENDENCIES = ['wemo']
  SCAN_INTERVAL = timedelta(seconds=10)
  
  _LOGGER = logging.getLogger(__name__)
  
  ATTR_SENSOR_STATE = 'sensor_state'
  ATTR_SWITCH_MODE = 'switch_mode'
  ATTR_CURRENT_STATE_DETAIL = 'state_detail'
  ATTR_COFFEMAKER_MODE = 'coffeemaker_mode'
  
  MAKER_SWITCH_MOMENTARY = 'momentary'
  MAKER_SWITCH_TOGGLE = 'toggle'
  
  WEMO_ON = 1
  WEMO_OFF = 0
  WEMO_STANDBY = 8
  
  
  # pylint: disable=too-many-function-args
  def setup_platform(hass, config, add_devices_callback, discovery_info=None):
      """Set up discovered WeMo switches."""
      import pywemo.discovery as discovery
  
      if discovery_info is not None:
          location = discovery_info['ssdp_description']
          mac = discovery_info['mac_address']
          device = discovery.device_from_description(location, mac)
  
          if device:
              add_devices_callback([WemoSwitch(device)])
  
  
  class WemoSwitch(SwitchDevice):
      """Representation of a WeMo switch."""
  
      def __init__(self, device):
          """Initialize the WeMo switch."""
          self.wemo = device
          self.insight_params = None
          self.maker_params = None
          self.coffeemaker_mode = None
          self._state = None
          self._available = True
          self._update_lock = None
          # look up model name once as it incurs network traffic
          self._model_name = self.wemo.model_name
  
      def _subscription_callback(self, _device, _type, _params):
          """Update the state by the Wemo device."""
          _LOGGER.info("Subscription update for %s", self.name)
          updated = self.wemo.subscription_update(_type, _params)
          self.hass.add_job(
              self._async_locked_subscription_callback(not updated))
  
      async def _async_locked_subscription_callback(self, force_update):
          """Helper to handle an update from a subscription."""
          # If an update is in progress, we don't do anything
          if self._update_lock.locked():
              return
  
          await self._async_locked_update(force_update)
          self.async_schedule_update_ha_state()
  
      @property
      def should_poll(self):
          """Device should poll.
  
          Subscriptions push the state, however it won't detect if a device
          is no longer available. Use polling to detect if a device is available.
          """
          return True
  
      @property
      def unique_id(self):
          """Return the ID of this WeMo switch."""
          return self.wemo.serialnumber
  
      @property
      def name(self):
          """Return the name of the switch if any."""
          return self.wemo.name
  
      @property
      def device_state_attributes(self):
          """Return the state attributes of the device."""
          attr = {}
          if self.maker_params:
              # Is the maker sensor on or off.
              if self.maker_params['hassensor']:
                  # Note a state of 1 matches the WeMo app 'not triggered'!
                  if self.maker_params['sensorstate']:
                      attr[ATTR_SENSOR_STATE] = STATE_OFF
                  else:
                      attr[ATTR_SENSOR_STATE] = STATE_ON
  
              # Is the maker switch configured as toggle(0) or momentary (1).
              if self.maker_params['switchmode']:
                  attr[ATTR_SWITCH_MODE] = MAKER_SWITCH_MOMENTARY
              else:
                  attr[ATTR_SWITCH_MODE] = MAKER_SWITCH_TOGGLE
  
          if self.insight_params or (self.coffeemaker_mode is not None):
              attr[ATTR_CURRENT_STATE_DETAIL] = self.detail_state
  
          if self.insight_params:
              attr['on_latest_time'] = \
                  WemoSwitch.as_uptime(self.insight_params['onfor'])
              attr['on_today_time'] = \
                  WemoSwitch.as_uptime(self.insight_params['ontoday'])
              attr['on_total_time'] = \
                  WemoSwitch.as_uptime(self.insight_params['ontotal'])
              attr['power_threshold_w'] = \
                  convert(
                      self.insight_params['powerthreshold'], float, 0.0
                  ) / 1000.0
  
          if self.coffeemaker_mode is not None:
              attr[ATTR_COFFEMAKER_MODE] = self.coffeemaker_mode
  
          return attr
  
      @staticmethod
      def as_uptime(_seconds):
          """Format seconds into uptime string in the format: 00d 00h 00m 00s."""
          uptime = datetime(1, 1, 1) + timedelta(seconds=_seconds)
          return "{:0>2d}d {:0>2d}h {:0>2d}m {:0>2d}s".format(
              uptime.day-1, uptime.hour, uptime.minute, uptime.second)
  
      @property
      def current_power_w(self):
          """Return the current power usage in W."""
          if self.insight_params:
              return convert(
                  self.insight_params['currentpower'], float, 0.0
                  ) / 1000.0
  
      @property
      def today_energy_kwh(self):
          """Return the today total energy usage in kWh."""
          if self.insight_params:
              miliwatts = convert(self.insight_params['todaymw'], float, 0.0)
              return round(miliwatts / (1000.0 * 1000.0 * 60), 2)
  
      @property
      def detail_state(self):
          """Return the state of the device."""
          if self.coffeemaker_mode is not None:
              return self.wemo.mode_string
          if self.insight_params:
              standby_state = int(self.insight_params['state'])
              if standby_state == WEMO_ON:
                  return STATE_ON
              elif standby_state == WEMO_OFF:
                  return STATE_OFF
              elif standby_state == WEMO_STANDBY:
                  return STATE_STANDBY
              return STATE_UNKNOWN
  
      @property
      def is_on(self):
          """Return true if switch is on. Standby is on."""
          return self._state
  
      @property
      def available(self):
          """Return true if switch is available."""
          return self._available
  
      @property
      def icon(self):
          """Return the icon of device based on its type."""
          if self._model_name == 'CoffeeMaker':
              return 'mdi:coffee'
          return None
  
      def turn_on(self, **kwargs):
          """Turn the switch on."""
          self.wemo.on()
  
      def turn_off(self, **kwargs):
          """Turn the switch off."""
          self.wemo.off()
  
      async def async_added_to_hass(self):
          """Wemo switch added to HASS."""
          # Define inside async context so we know our event loop
          self._update_lock = asyncio.Lock()
  
          registry = self.hass.components.wemo.SUBSCRIPTION_REGISTRY
          await self.hass.async_add_job(registry.register, self.wemo)
          registry.on(self.wemo, None, self._subscription_callback)
  
      async def async_update(self):
          """Update WeMo state.
  
          Wemo has an aggressive retry logic that sometimes can take over a
          minute to return. If we don't get a state after 5 seconds, assume the
          Wemo switch is unreachable. If update goes through, it will be made
          available again.
          """
          # If an update is in progress, we don't do anything
          if self._update_lock.locked():
              return
  
          try:
              with async_timeout.timeout(5):
                  await asyncio.shield(self._async_locked_update(True))
          except asyncio.TimeoutError:
              _LOGGER.warning('Lost connection to %s', self.name)
              self._available = False
  
      async def _async_locked_update(self, force_update):
          """Try updating within an async lock."""
          async with self._update_lock:
              await self.hass.async_add_job(self._update, force_update)
  
      def _update(self, force_update):
          """Update the device state."""
          try:
              self._state = self.wemo.get_state(force_update)
              if self._model_name == 'Insight':
                  self.insight_params = self.wemo.insight_params
                  self.insight_params['standby_state'] = (
                      self.wemo.get_standby_state)
              elif self._model_name == 'Maker':
                  self.maker_params = self.wemo.maker_params
              elif self._model_name == 'CoffeeMaker':
                  self.coffeemaker_mode = self.wemo.mode
  
              if not self._available:
                  _LOGGER.info('Reconnected to %s', self.name)
                  self._available = True
          except AttributeError as err:
              _LOGGER.warning("Could not update status for %s (%s)",
                              self.name, err)
              self._available = False
  