"""
homeassistant.components.switch.arduino
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Support for switching Arduino pins on and off. So far only digital pins are
supported.

Configuration:

To use the arduino switch you will need to add something like the following
to your configuration.yaml file.

switch:
  platform: arduino
  pins:
    11:
      name: Fan Office
      type: digital
    12:
      name: Light Desk
      type: digital

Variables:

pins
*Required
An array specifying the digital pins to use on the Arduino board.

These are the variables for the pins array:

name
*Required
The name for the pin that will be used in the frontend.

type
*Required
The type of the pin: 'digital'.
"""
import logging

import homeassistant.components.arduino as arduino
from homeassistant.components.switch import SwitchDevice
from homeassistant.const import DEVICE_DEFAULT_NAME

DEPENDENCIES = ['arduino']

_LOGGER = logging.getLogger(__name__)


def setup_platform(hass, config, add_devices, discovery_info=None):
    """ Sets up the Arduino platform. """

    # Verify that Arduino board is present
    if arduino.BOARD is None:
        _LOGGER.error('A connection has not been made to the Arduino board.')
        return False

    switches = []
    pins = config.get('pins')
    for pinnum, pin in pins.items():
        if pin.get('name'):
            switches.append(ArduinoSwitch(pin.get('name'),
                                          pinnum,
                                          pin.get('type')))
    add_devices(switches)


class ArduinoSwitch(SwitchDevice):
    """ Represents an Arduino switch. """
    def __init__(self, name, pin, pin_type):
        self._pin = pin
        self._name = name or DEVICE_DEFAULT_NAME
        self.pin_type = pin_type
        self.direction = 'out'
        self._state = False

        arduino.BOARD.set_mode(self._pin, self.direction, self.pin_type)

    @property
    def name(self):
        """ Get the name of the pin. """
        return self._name

    @property
    def is_on(self):
        """ Returns True if pin is high/on. """
        return self._state

    def turn_on(self):
        """ Turns the pin to high/on. """
        self._state = True
        arduino.BOARD.set_digital_out_high(self._pin)

    def turn_off(self):
        """ Turns the pin to low/off. """
        self._state = False
        arduino.BOARD.set_digital_out_low(self._pin)