var logger = require('winston');
var sensor = require("ds18x20")
var devices;
var channel;

module.exports.start = function(channel_config){
  channel = channel_config
  logger.info("Starting External temperature module");
  var isLoaded = sensor.isDriverLoaded();
  if(isLoaded){
    logger.info("ds18x20 sensor drivers are loaded.")
    devices = sensor.list();
    console.log(devices);
    setInterval(function () {
      var temperature = readSensor();
    }, 5000);
  } else {
    logger.info("ds18x20 sensor drivers are not loaded.")
  }


}

function readSensor() {
  // Read Sensor data
  if(devices == undefined){
    devices = sensor.list();
  }
  sensor.get(devices[devices.length - 1], function(err, temp){
  	if(err){
  		console.log(err);
  	}
  	channel.emit('temperature_external', { temperature: temp });
  });
}