hybridgroup/cylon-powerup

/*
 * cylon-powerup driver
 * http://cylonjs.com
 *
 * Copyright (c) 2014 The Hybrid Group
 * Licensed under the Apache 2.0 license.
*/

"use strict";

var Cylon = require("cylon");

var MOTOR = "75b64e51f1844ed1921a476090d80ba7",
    RUDDER = "75b64e51f1854ed1921a476090d80ba7";

var Driver = module.exports = function Driver() {
  Driver.__super__.constructor.apply(this, arguments);

  this.serviceId = "75b64e51f1814ed1921a476090d80ba7";

  this.commands = {
    setThrust: this.setThrust,
    setRudder: this.setRudder
  };
};

Cylon.Utils.subclass(Driver, Cylon.Driver);

/**
 * Starts the driver
 *
 * @param {Function} callback to be triggered when started
 * @return {void}
 */
Driver.prototype.start = function(callback) {
  callback();
};

/**
 * Stops the driver
 *
 * @param {Function} callback to be triggered when halted
 * @return {void}
 */
Driver.prototype.halt = function(callback) {
  callback();
};

/**
 * Sets the thrust value of the Powerup
 *
 * @param {Number} value the new value for the Powerup's thrust
 * @param {Function} callback to be triggered when the value is written
 * @return {void}
 * @publish
 */
Driver.prototype.setThrust = function(value, callback) {
  this._writeServiceCharacteristic(value, MOTOR, callback);
};

/**
 * Sets the rudder value of the Powerup
 *
 * @param {Number} value the new value for the Powerup's rudder
 * @param {Function} callback to be triggered when the value is written
 * @return {void}
 * @publish
 */
Driver.prototype.setRudder = function(value, callback) {
  this._writeServiceCharacteristic(value, RUDDER, callback);
};

Driver.prototype._writeServiceCharacteristic = function(value, char, callback) {
  this.connection.writeServiceCharacteristic(
    this.serviceId,
    char,
    new Buffer([value]),
    function(err) {
      if (typeof callback === "function") { callback(err); }
    }
  );
};