__init__.py

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"""Support for LIRC devices."""
 
import logging
import threading
import time
 
import lirc
 
from homeassistant.const import EVENT_HOMEASSISTANT_START, EVENT_HOMEASSISTANT_STOP
from homeassistant.core import HomeAssistant
from homeassistant.helpers import config_validation as cv
from homeassistant.helpers.typing import ConfigType
 
_LOGGER = logging.getLogger(__name__)
 
BUTTON_NAME = "button_name"
 
DOMAIN = "lirc"
 
EVENT_IR_COMMAND_RECEIVED = "ir_command_received"
 
ICON = "mdi:remote"
 
CONFIG_SCHEMA = cv.empty_config_schema(DOMAIN)
 
 
def setup(hass: HomeAssistant, config: ConfigType) -> bool:
    """Set up the LIRC capability."""
    # blocking=True gives unexpected behavior (multiple responses for 1 press)
    # also by not blocking, we allow hass to shut down the thread gracefully
    # on exit.
    lirc.init("home-assistant", blocking=False)
    lirc_interface = LircInterface(hass)
 
    def _start_lirc(_event):
        lirc_interface.start()
 
    def _stop_lirc(_event):
        lirc_interface.stopped.set()
 
    hass.bus.listen_once(EVENT_HOMEASSISTANT_START, _start_lirc)
    hass.bus.listen_once(EVENT_HOMEASSISTANT_STOP, _stop_lirc)
 
    return True
 
 
class LircInterface(threading.Thread):
    """Interfaces with the lirc daemon to read IR commands.
 
    When using lirc in blocking mode, sometimes repeated commands get produced
    in the next read of a command so we use a thread here to just wait
    around until a non-empty response is obtained from lirc.
    """
 
    def __init__(self, hass):
        """Construct a LIRC interface object."""
        threading.Thread.__init__(self)
        self.daemondaemon = True
        self.stoppedstopped = threading.Event()
        self.hasshass = hass
 
    def run(self):
        """Run the loop of the LIRC interface thread."""
        _LOGGER.debug("LIRC interface thread started")
        while not self.stoppedstopped.is_set():
            try:
                code = lirc.nextcode()  # list; empty if no buttons pressed
            except lirc.NextCodeError:
                _LOGGER.warning("Error reading next code from LIRC")
                code = None
            # interpret result from python-lirc
            if code:
                code = code[0]
                _LOGGER.debug("Got new LIRC code %s", code)
                self.hasshass.bus.fire(EVENT_IR_COMMAND_RECEIVED, {BUTTON_NAME: code})
            else:
                time.sleep(0.2)
        lirc.deinit()
        _LOGGER.debug("LIRC interface thread stopped")