text: """
  Support for MQTT JSON lights.
  
  For more details about this platform, please refer to the documentation at
  https://home-assistant.io/components/light.mqtt_json/
  """
  import asyncio
  import logging
  import json
  import voluptuous as vol
  
  from homeassistant.core import callback
  import homeassistant.components.mqtt as mqtt
  from homeassistant.components.light import (
      ATTR_BRIGHTNESS, ATTR_COLOR_TEMP, ATTR_EFFECT, ATTR_FLASH,
      ATTR_RGB_COLOR, ATTR_TRANSITION, ATTR_WHITE_VALUE, ATTR_XY_COLOR,
      FLASH_LONG, FLASH_SHORT, Light, PLATFORM_SCHEMA, SUPPORT_BRIGHTNESS,
      SUPPORT_COLOR_TEMP, SUPPORT_EFFECT, SUPPORT_FLASH, SUPPORT_RGB_COLOR,
      SUPPORT_TRANSITION, SUPPORT_WHITE_VALUE, SUPPORT_XY_COLOR)
  from homeassistant.const import (
      CONF_BRIGHTNESS, CONF_COLOR_TEMP, CONF_EFFECT,
      CONF_NAME, CONF_OPTIMISTIC, CONF_RGB, CONF_WHITE_VALUE, CONF_XY)
  from homeassistant.components.mqtt import (
      CONF_STATE_TOPIC, CONF_COMMAND_TOPIC, CONF_QOS, CONF_RETAIN)
  import homeassistant.helpers.config_validation as cv
  
  _LOGGER = logging.getLogger(__name__)
  
  DOMAIN = 'mqtt_json'
  
  DEPENDENCIES = ['mqtt']
  
  DEFAULT_BRIGHTNESS = False
  DEFAULT_COLOR_TEMP = False
  DEFAULT_EFFECT = False
  DEFAULT_FLASH_TIME_LONG = 10
  DEFAULT_FLASH_TIME_SHORT = 2
  DEFAULT_NAME = 'MQTT JSON Light'
  DEFAULT_OPTIMISTIC = False
  DEFAULT_RGB = False
  DEFAULT_WHITE_VALUE = False
  DEFAULT_XY = False
  
  CONF_EFFECT_LIST = 'effect_list'
  
  CONF_FLASH_TIME_LONG = 'flash_time_long'
  CONF_FLASH_TIME_SHORT = 'flash_time_short'
  
  # Stealing some of these from the base MQTT configs.
  PLATFORM_SCHEMA = PLATFORM_SCHEMA.extend({
      vol.Optional(CONF_BRIGHTNESS, default=DEFAULT_BRIGHTNESS): cv.boolean,
      vol.Optional(CONF_COLOR_TEMP, default=DEFAULT_COLOR_TEMP): cv.boolean,
      vol.Optional(CONF_EFFECT, default=DEFAULT_EFFECT): cv.boolean,
      vol.Optional(CONF_EFFECT_LIST): vol.All(cv.ensure_list, [cv.string]),
      vol.Optional(CONF_FLASH_TIME_SHORT, default=DEFAULT_FLASH_TIME_SHORT):
          cv.positive_int,
      vol.Optional(CONF_FLASH_TIME_LONG, default=DEFAULT_FLASH_TIME_LONG):
          cv.positive_int,
      vol.Optional(CONF_NAME, default=DEFAULT_NAME): cv.string,
      vol.Optional(CONF_OPTIMISTIC, default=DEFAULT_OPTIMISTIC): cv.boolean,
      vol.Optional(CONF_QOS, default=mqtt.DEFAULT_QOS):
          vol.All(vol.Coerce(int), vol.In([0, 1, 2])),
      vol.Optional(CONF_RETAIN, default=mqtt.DEFAULT_RETAIN): cv.boolean,
      vol.Optional(CONF_RGB, default=DEFAULT_RGB): cv.boolean,
      vol.Optional(CONF_STATE_TOPIC): mqtt.valid_subscribe_topic,
      vol.Optional(CONF_WHITE_VALUE, default=DEFAULT_WHITE_VALUE): cv.boolean,
      vol.Optional(CONF_XY, default=DEFAULT_XY): cv.boolean,
      vol.Required(CONF_COMMAND_TOPIC): mqtt.valid_publish_topic,
  })
  
  
  @asyncio.coroutine
  def async_setup_platform(hass, config, async_add_devices, discovery_info=None):
      """Set up a MQTT JSON Light."""
      if discovery_info is not None:
          config = PLATFORM_SCHEMA(discovery_info)
      async_add_devices([MqttJson(
          config.get(CONF_NAME),
          config.get(CONF_EFFECT_LIST),
          {
              key: config.get(key) for key in (
                  CONF_STATE_TOPIC,
                  CONF_COMMAND_TOPIC
              )
          },
          config.get(CONF_QOS),
          config.get(CONF_RETAIN),
          config.get(CONF_OPTIMISTIC),
          config.get(CONF_BRIGHTNESS),
          config.get(CONF_COLOR_TEMP),
          config.get(CONF_EFFECT),
          config.get(CONF_RGB),
          config.get(CONF_WHITE_VALUE),
          config.get(CONF_XY),
          {
              key: config.get(key) for key in (
                  CONF_FLASH_TIME_SHORT,
                  CONF_FLASH_TIME_LONG
              )
          }
      )])
  
  
  class MqttJson(Light):
      """Representation of a MQTT JSON light."""
  
      def __init__(self, name, effect_list, topic, qos, retain, optimistic,
                   brightness, color_temp, effect, rgb, white_value, xy,
                   flash_times):
          """Initialize MQTT JSON light."""
          self._name = name
          self._effect_list = effect_list
          self._topic = topic
          self._qos = qos
          self._retain = retain
          self._optimistic = optimistic or topic[CONF_STATE_TOPIC] is None
          self._state = False
          if brightness:
              self._brightness = 255
          else:
              self._brightness = None
  
          if color_temp:
              self._color_temp = 150
          else:
              self._color_temp = None
  
          if effect:
              self._effect = 'none'
          else:
              self._effect = None
  
          if rgb:
              self._rgb = [0, 0, 0]
          else:
              self._rgb = None
  
          if white_value:
              self._white_value = 255
          else:
              self._white_value = None
  
          if xy:
              self._xy = [1, 1]
          else:
              self._xy = None
  
          self._flash_times = flash_times
  
          self._supported_features = (SUPPORT_TRANSITION | SUPPORT_FLASH)
          self._supported_features |= (rgb and SUPPORT_RGB_COLOR)
          self._supported_features |= (brightness and SUPPORT_BRIGHTNESS)
          self._supported_features |= (color_temp and SUPPORT_COLOR_TEMP)
          self._supported_features |= (effect and SUPPORT_EFFECT)
          self._supported_features |= (white_value and SUPPORT_WHITE_VALUE)
          self._supported_features |= (xy and SUPPORT_XY_COLOR)
  
      @asyncio.coroutine
      def async_added_to_hass(self):
          """Subscribe to MQTT events.
  
          This method is a coroutine.
          """
          @callback
          def state_received(topic, payload, qos):
              """Handle new MQTT messages."""
              values = json.loads(payload)
  
              if values['state'] == 'ON':
                  self._state = True
              elif values['state'] == 'OFF':
                  self._state = False
  
              if self._rgb is not None:
                  try:
                      red = int(values['color']['r'])
                      green = int(values['color']['g'])
                      blue = int(values['color']['b'])
  
                      self._rgb = [red, green, blue]
                  except KeyError:
                      pass
                  except ValueError:
                      _LOGGER.warning("Invalid RGB color value received")
  
              if self._brightness is not None:
                  try:
                      self._brightness = int(values['brightness'])
                  except KeyError:
                      pass
                  except ValueError:
                      _LOGGER.warning("Invalid brightness value received")
  
              if self._color_temp is not None:
                  try:
                      self._color_temp = int(values['color_temp'])
                  except KeyError:
                      pass
                  except ValueError:
                      _LOGGER.warning("Invalid color temp value received")
  
              if self._effect is not None:
                  try:
                      self._effect = values['effect']
                  except KeyError:
                      pass
                  except ValueError:
                      _LOGGER.warning("Invalid effect value received")
  
              if self._white_value is not None:
                  try:
                      self._white_value = int(values['white_value'])
                  except KeyError:
                      pass
                  except ValueError:
                      _LOGGER.warning("Invalid white value value received")
  
              if self._xy is not None:
                  try:
                      x_color = float(values['color']['x'])
                      y_color = float(values['color']['y'])
  
                      self._xy = [x_color, y_color]
                  except KeyError:
                      pass
                  except ValueError:
                      _LOGGER.warning("Invalid XY color value received")
  
              self.async_schedule_update_ha_state()
  
          if self._topic[CONF_STATE_TOPIC] is not None:
              yield from mqtt.async_subscribe(
                  self.hass, self._topic[CONF_STATE_TOPIC], state_received,
                  self._qos)
  
      @property
      def brightness(self):
          """Return the brightness of this light between 0..255."""
          return self._brightness
  
      @property
      def color_temp(self):
          """Return the color temperature in mired."""
          return self._color_temp
  
      @property
      def effect(self):
          """Return the current effect."""
          return self._effect
  
      @property
      def effect_list(self):
          """Return the list of supported effects."""
          return self._effect_list
  
      @property
      def rgb_color(self):
          """Return the RGB color value."""
          return self._rgb
  
      @property
      def white_value(self):
          """Return the white property."""
          return self._white_value
  
      @property
      def xy_color(self):
          """Return the XY color value."""
          return self._xy
  
      @property
      def should_poll(self):
          """No polling needed for a MQTT light."""
          return False
  
      @property
      def name(self):
          """Return the name of the device if any."""
          return self._name
  
      @property
      def is_on(self):
          """Return true if device is on."""
          return self._state
  
      @property
      def assumed_state(self):
          """Return true if we do optimistic updates."""
          return self._optimistic
  
      @property
      def supported_features(self):
          """Flag supported features."""
          return self._supported_features
  
      @asyncio.coroutine
      def async_turn_on(self, **kwargs):
          """Turn the device on.
  
          This method is a coroutine.
          """
          should_update = False
  
          message = {'state': 'ON'}
  
          if ATTR_RGB_COLOR in kwargs:
              message['color'] = {
                  'r': kwargs[ATTR_RGB_COLOR][0],
                  'g': kwargs[ATTR_RGB_COLOR][1],
                  'b': kwargs[ATTR_RGB_COLOR][2]
              }
  
              if self._optimistic:
                  self._rgb = kwargs[ATTR_RGB_COLOR]
                  should_update = True
  
          if ATTR_FLASH in kwargs:
              flash = kwargs.get(ATTR_FLASH)
  
              if flash == FLASH_LONG:
                  message['flash'] = self._flash_times[CONF_FLASH_TIME_LONG]
              elif flash == FLASH_SHORT:
                  message['flash'] = self._flash_times[CONF_FLASH_TIME_SHORT]
  
          if ATTR_TRANSITION in kwargs:
              message['transition'] = int(kwargs[ATTR_TRANSITION])
  
          if ATTR_BRIGHTNESS in kwargs:
              message['brightness'] = int(kwargs[ATTR_BRIGHTNESS])
  
              if self._optimistic:
                  self._brightness = kwargs[ATTR_BRIGHTNESS]
                  should_update = True
  
          if ATTR_COLOR_TEMP in kwargs:
              message['color_temp'] = int(kwargs[ATTR_COLOR_TEMP])
  
              if self._optimistic:
                  self._color_temp = kwargs[ATTR_COLOR_TEMP]
                  should_update = True
  
          if ATTR_EFFECT in kwargs:
              message['effect'] = kwargs[ATTR_EFFECT]
  
              if self._optimistic:
                  self._effect = kwargs[ATTR_EFFECT]
                  should_update = True
  
          if ATTR_WHITE_VALUE in kwargs:
              message['white_value'] = int(kwargs[ATTR_WHITE_VALUE])
  
              if self._optimistic:
                  self._white_value = kwargs[ATTR_WHITE_VALUE]
                  should_update = True
  
          if ATTR_XY_COLOR in kwargs:
              message['color'] = {
                  'x': kwargs[ATTR_XY_COLOR][0],
                  'y': kwargs[ATTR_XY_COLOR][1]
              }
  
              if self._optimistic:
                  self._xy = kwargs[ATTR_XY_COLOR]
                  should_update = True
  
          mqtt.async_publish(
              self.hass, self._topic[CONF_COMMAND_TOPIC], json.dumps(message),
              self._qos, self._retain)
  
          if self._optimistic:
              # Optimistically assume that the light has changed state.
              self._state = True
              should_update = True
  
          if should_update:
              self.async_schedule_update_ha_state()
  
      @asyncio.coroutine
      def async_turn_off(self, **kwargs):
          """Turn the device off.
  
          This method is a coroutine.
          """
          message = {'state': 'OFF'}
  
          if ATTR_TRANSITION in kwargs:
              message['transition'] = int(kwargs[ATTR_TRANSITION])
  
          mqtt.async_publish(
              self.hass, self._topic[CONF_COMMAND_TOPIC], json.dumps(message),
              self._qos, self._retain)
  
          if self._optimistic:
              # Optimistically assume that the light has changed state.
              self._state = False
              self.async_schedule_update_ha_state()
  