"""
Support for OpenTherm Gateway climate devices.

For more details about this platform, please refer to the documentation at
http://home-assistant.io/components/climate.opentherm_gw/
"""
import logging

from homeassistant.components.climate import (ClimateDevice, STATE_IDLE,
                                              STATE_HEAT, STATE_COOL,
                                              SUPPORT_TARGET_TEMPERATURE)
from homeassistant.components.opentherm_gw import (
    CONF_FLOOR_TEMP, CONF_PRECISION, DATA_DEVICE, DATA_GW_VARS,
    DATA_OPENTHERM_GW, SIGNAL_OPENTHERM_GW_UPDATE)
from homeassistant.const import (ATTR_TEMPERATURE, CONF_NAME, PRECISION_HALVES,
                                 PRECISION_TENTHS, PRECISION_WHOLE,
                                 TEMP_CELSIUS)
from homeassistant.helpers.dispatcher import async_dispatcher_connect

DEPENDENCIES = ['opentherm_gw']

SUPPORT_FLAGS = (SUPPORT_TARGET_TEMPERATURE)
_LOGGER = logging.getLogger(__name__)


async def async_setup_platform(hass, config, async_add_entities,
                               discovery_info=None):
    """Set up the opentherm_gw device."""
    gateway = OpenThermGateway(hass, discovery_info)
    async_add_entities([gateway])


class OpenThermGateway(ClimateDevice):
    """Representation of a climate device."""

    def __init__(self, hass, config):
        """Initialize the device."""
        self._gateway = hass.data[DATA_OPENTHERM_GW][DATA_DEVICE]
        self._gw_vars = hass.data[DATA_OPENTHERM_GW][DATA_GW_VARS]
        self.friendly_name = config.get(CONF_NAME)
        self.floor_temp = config.get(CONF_FLOOR_TEMP)
        self.temp_precision = config.get(CONF_PRECISION)
        self._current_operation = STATE_IDLE
        self._current_temperature = 0.0
        self._target_temperature = 0.0
        self._away_mode_a = None
        self._away_mode_b = None
        self._away_state_a = False
        self._away_state_b = False

    async def async_added_to_hass(self):
        """Connect to the OpenTherm Gateway device."""
        _LOGGER.debug("Added device %s", self.friendly_name)
        async_dispatcher_connect(self.hass, SIGNAL_OPENTHERM_GW_UPDATE,
                                 self.receive_report)

    async def receive_report(self, status):
        """Receive and handle a new report from the Gateway."""
        ch_active = status.get(self._gw_vars.DATA_SLAVE_CH_ACTIVE)
        flame_on = status.get(self._gw_vars.DATA_SLAVE_FLAME_ON)
        cooling_active = status.get(self._gw_vars.DATA_SLAVE_COOLING_ACTIVE)
        if ch_active and flame_on:
            self._current_operation = STATE_HEAT
        elif cooling_active:
            self._current_operation = STATE_COOL
        else:
            self._current_operation = STATE_IDLE
        self._current_temperature = status.get(self._gw_vars.DATA_ROOM_TEMP)

        temp = status.get(self._gw_vars.DATA_ROOM_SETPOINT_OVRD)
        if temp is None:
            temp = status.get(self._gw_vars.DATA_ROOM_SETPOINT)
        self._target_temperature = temp

        # GPIO mode 5: 0 == Away
        # GPIO mode 6: 1 == Away
        gpio_a_state = status.get(self._gw_vars.OTGW_GPIO_A)
        if gpio_a_state == 5:
            self._away_mode_a = 0
        elif gpio_a_state == 6:
            self._away_mode_a = 1
        else:
            self._away_mode_a = None
        gpio_b_state = status.get(self._gw_vars.OTGW_GPIO_B)
        if gpio_b_state == 5:
            self._away_mode_b = 0
        elif gpio_b_state == 6:
            self._away_mode_b = 1
        else:
            self._away_mode_b = None
        if self._away_mode_a is not None:
            self._away_state_a = (status.get(
                self._gw_vars.OTGW_GPIO_A_STATE) == self._away_mode_a)
        if self._away_mode_b is not None:
            self._away_state_b = (status.get(
                self._gw_vars.OTGW_GPIO_B_STATE) == self._away_mode_b)
        self.async_schedule_update_ha_state()

    @property
    def name(self):
        """Return the friendly name."""
        return self.friendly_name

    @property
    def precision(self):
        """Return the precision of the system."""
        if self.temp_precision is not None:
            return self.temp_precision
        if self.hass.config.units.temperature_unit == TEMP_CELSIUS:
            return PRECISION_HALVES
        return PRECISION_WHOLE

    @property
    def should_poll(self):
        """Disable polling for this entity."""
        return False

    @property
    def temperature_unit(self):
        """Return the unit of measurement used by the platform."""
        return TEMP_CELSIUS

    @property
    def current_operation(self):
        """Return current operation ie. heat, cool, idle."""
        return self._current_operation

    @property
    def current_temperature(self):
        """Return the current temperature."""
        if self.floor_temp is True:
            if self.temp_precision == PRECISION_HALVES:
                return int(2 * self._current_temperature) / 2
            if self.temp_precision == PRECISION_TENTHS:
                return int(10 * self._current_temperature) / 10
            return int(self._current_temperature)
        return self._current_temperature

    @property
    def target_temperature(self):
        """Return the temperature we try to reach."""
        return self._target_temperature

    @property
    def target_temperature_step(self):
        """Return the supported step of target temperature."""
        return self.temp_precision

    @property
    def is_away_mode_on(self):
        """Return true if away mode is on."""
        return self._away_state_a or self._away_state_b

    async def async_set_temperature(self, **kwargs):
        """Set new target temperature."""
        if ATTR_TEMPERATURE in kwargs:
            temp = float(kwargs[ATTR_TEMPERATURE])
            self._target_temperature = await self._gateway.set_target_temp(
                temp)
            self.async_schedule_update_ha_state()

    @property
    def supported_features(self):
        """Return the list of supported features."""
        return SUPPORT_FLAGS

    @property
    def min_temp(self):
        """Return the minimum temperature."""
        return 1

    @property
    def max_temp(self):
        """Return the maximum temperature."""
        return 30
