"""
Interfaces with Z-Wave sensors.

For more details about this platform, please refer to the documentation
at https://home-assistant.io/components/sensor.zwave/
"""
# Because we do not compile openzwave on CI
# pylint: disable=import-error
from homeassistant.components.sensor import DOMAIN
from homeassistant.components.zwave import (
    ATTR_NODE_ID, ATTR_VALUE_ID, COMMAND_CLASS_ALARM, COMMAND_CLASS_METER,
    COMMAND_CLASS_SENSOR_MULTILEVEL, NETWORK,
    TYPE_DECIMAL, ZWaveDeviceEntity)
from homeassistant.const import (TEMP_CELCIUS, TEMP_FAHRENHEIT)
from homeassistant.helpers.entity import Entity


FIBARO = 0x010f
FIBARO_WALL_PLUG = 0x1000
FIBARO_WALL_PLUG_SENSOR_METER = (FIBARO, FIBARO_WALL_PLUG, 8)

WORKAROUND_IGNORE = 'ignore'

DEVICE_MAPPINGS = {
    # For some reason Fibaro Wall Plug reports 2 power consumptions.
    # One value updates as the power consumption changes
    # and the other does not change.
    FIBARO_WALL_PLUG_SENSOR_METER: WORKAROUND_IGNORE,
}


def setup_platform(hass, config, add_devices, discovery_info=None):
    """Setup Z-Wave sensors."""
    # Return on empty `discovery_info`. Given you configure HA with:
    #
    # sensor:
    #   platform: zwave
    #
    # `setup_platform` will be called without `discovery_info`.
    if discovery_info is None or NETWORK is None:
        return

    node = NETWORK.nodes[discovery_info[ATTR_NODE_ID]]
    value = node.values[discovery_info[ATTR_VALUE_ID]]

    value.set_change_verified(False)

    # if 1 in groups and (NETWORK.controller.node_id not in
    #                     groups[1].associations):
    #     node.groups[1].add_association(NETWORK.controller.node_id)

    # Make sure that we have values for the key before converting to int
    if (value.node.manufacturer_id.strip() and
            value.node.product_id.strip()):
        specific_sensor_key = (int(value.node.manufacturer_id, 16),
                               int(value.node.product_id, 16),
                               value.index)

        # Check workaround mappings for specific devices.
        if specific_sensor_key in DEVICE_MAPPINGS:
            if DEVICE_MAPPINGS[specific_sensor_key] == WORKAROUND_IGNORE:
                return

    # Generic Device mappings
    if value.command_class == COMMAND_CLASS_SENSOR_MULTILEVEL:
        add_devices([ZWaveMultilevelSensor(value)])

    elif (value.command_class == COMMAND_CLASS_METER and
          value.type == TYPE_DECIMAL):
        add_devices([ZWaveMultilevelSensor(value)])

    elif value.command_class == COMMAND_CLASS_ALARM:
        add_devices([ZWaveAlarmSensor(value)])


class ZWaveSensor(ZWaveDeviceEntity, Entity):
    """Representation of a Z-Wave sensor."""

    def __init__(self, sensor_value):
        """Initialize the sensor."""
        from openzwave.network import ZWaveNetwork
        from pydispatch import dispatcher

        ZWaveDeviceEntity.__init__(self, sensor_value, DOMAIN)

        dispatcher.connect(
            self.value_changed, ZWaveNetwork.SIGNAL_VALUE_CHANGED)

    @property
    def state(self):
        """Return the state of the sensor."""
        return self._value.data

    @property
    def unit_of_measurement(self):
        """Return the unit of measurement the value is expressed in."""
        return self._value.units

    def value_changed(self, value):
        """Called when a value has changed on the network."""
        if self._value.value_id == value.value_id:
            self.update_ha_state()


class ZWaveMultilevelSensor(ZWaveSensor):
    """Representation of a multi level sensor Z-Wave sensor."""

    @property
    def state(self):
        """Return the state of the sensor."""
        value = self._value.data

        if self._value.units in ('C', 'F'):
            return round(value, 1)
        elif isinstance(value, float):
            return round(value, 2)

        return value

    @property
    def unit_of_measurement(self):
        """Return the unit the value is expressed in."""
        unit = self._value.units

        if unit == 'C':
            return TEMP_CELCIUS
        elif unit == 'F':
            return TEMP_FAHRENHEIT
        else:
            return unit


class ZWaveAlarmSensor(ZWaveSensor):
    """Representation of a Z-Wave sensor that sends Alarm alerts.

    Examples include certain Multisensors that have motion and vibration
    capabilities. Z-Wave defines various alarm types such as Smoke, Flood,
    Burglar, CarbonMonoxide, etc.

    This wraps these alarms and allows you to use them to trigger things, etc.

    COMMAND_CLASS_ALARM is what we get here.
    """

    pass