from mqtt import MqttMessage, MqttConfigMessage

from workers.base import BaseWorker
import logger
import subprocess
import traceback

REQUIREMENTS = []
_LOGGER = logger.get(__name__)


class LinuxhostWorker(BaseWorker):
    
    def mqttHomieDevice(self, name, nodes):
        return [
            MqttConfigMessage(self.format_topic(), "$state", payload="ready"),
            MqttConfigMessage(self.format_topic(), "$homie", payload="3.0"),
            MqttConfigMessage(self.format_topic(), "$name", payload=name),
            MqttConfigMessage(self.format_topic(), "$nodes", payload=nodes)
        ]

    
    def mqttHomieNode(self, label, name, properties):
        return [
            MqttConfigMessage(self.format_topic(label),  "$name", payload=name),
            MqttConfigMessage(self.format_topic(label),  "$properties", payload=properties),
        ]


    def mqttHomieProperty(self, node, prop, name, dtype, settable = False, retained = False, unit = None, dformat = None):
        retval = [
            MqttConfigMessage(self.format_topic(node, prop),  "$name", payload=name),
            MqttConfigMessage(self.format_topic(node, prop),  "$datatype", payload=dtype),
            MqttConfigMessage(self.format_topic(node, prop),  "$settable", payload="true" if settable else "false"),
            MqttConfigMessage(self.format_topic(node, prop),  "$retained", payload="true" if retained else "false")
        ]
        if unit is not None:
            retval.append(MqttConfigMessage(self.format_topic(node, prop),  "$unit", payload=unit))
        if dformat is not None:
            retval.append(MqttConfigMessage(self.format_topic(node, prop),  "$format", payload=dformat))
        return retval

    
    def _setup(self):
        pass


    def config(self):
        _LOGGER.debug("Configuring")
        retval = self.mqttHomieDevice("Linux Host", "xserver")
        retval += self.mqttHomieNode("xserver", "XServer", "screensaver")
        retval += self.mqttHomieProperty("xserver", "screensaver", "Screensaver", "enum", True, False, dformat="activate,deactivate")
        return retval


    def status_update(self):
        retval = []
        try:
            pass
        except Exception as e:
            _LOGGER.error("Caught exception in LinuxhostWorker.status_update(): {}".format(e))
            traceback.print_exc();
        return retval


    def on_command(self, topic, value):
        retval = []
        try:
            value = value.decode('utf-8')
            _, nodename, propname, operation = topic.split('/')
            _LOGGER.debug("Command \"%s\", on %s.%s: %s", operation, nodename, propname, value)
            if propname == "screensaver" and operation == "set":
                if value == "activate" and self._enableScreensaver() == 0:
                    retval.append(MqttMessage(topic=self.format_topic("xserver", "screensaver"), payload="activate", retain=False))
                elif value == "deactivate" and self._disableScreensaver() == 0:
                    retval.append(MqttMessage(topic=self.format_topic("xserver", "screensaver"), payload="deactivate", retain=False))
        except Exception as e:
            _LOGGER.error("Caught exception in LinuxhostWorker.on_command(): {}".format(e))
            traceback.print_exc();
        return retval


    def _enableScreensaver(self):
        try:
            _LOGGER.info('Enable Screensaver')
            return subprocess.call("DISPLAY=:0.0 sudo -u pi /usr/bin/xscreensaver-command -activate", shell=True)
        except Exception as e:
            logging.error("Caught Exception in LinuxhostWorker.enableScreensaver: " + str(e))
            return -1


    def _disableScreensaver(self):
        try:
            _LOGGER.info('Disable Screensaver')
            return subprocess.call("DISPLAY=:0.0 sudo -u pi /usr/bin/xscreensaver-command -deactivate", shell=True)
        except Exception as e:
            logging.error("Caught Exception in LinuxhostWorker.disableScreensaver: " + str(e))
            return -1