lifx-lan-client/src/lifx/packets/setColorZones.js

Node.js implementation of the LIFX LAN protocol

'use strict';

const {constants} = require('../../lifx');

const Packet = {
  size: 15
};

/**
 * Converts packet specific data from a buffer to an object
 * @param  {Buffer} buf Buffer containing only packet specific data no header
 * @return {Object}     Information contained in packet
 */
Packet.toObject = function(buf) {
  const obj = {};
  let offset = 0;

  if (buf.length !== this.size) {
    throw new Error('Invalid length given for setColorZones LIFX packet');
  }

  obj.startIndex = buf.readUInt8(offset);
  offset += 1;

  obj.endIndex = buf.readUInt8(offset);
  offset += 1;

  obj.color = {};
  obj.color.hue = buf.readUInt16LE(offset);
  offset += 2;
  obj.color.saturation = buf.readUInt16LE(offset);
  offset += 2;
  obj.color.brightness = buf.readUInt16LE(offset);
  offset += 2;
  obj.color.kelvin = buf.readUInt16LE(offset);
  offset += 2;

  obj.duration = buf.readUInt32LE(offset);
  offset += 4;

  obj.apply = buf.readUInt8(offset);
  offset += 1;

  return obj;
};

/**
 * Converts the given packet specific object into a packet
 * @param  {Object} obj object with configuration data
 * @param  {Number} obj.startIndex between 0 and 255
 * @param  {Number} obj.endIndex between 0 and 255
 * @param  {Object} obj.color an object with colors to set
 * @param  {Number} obj.color.hue between 0 and 65535
 * @param  {Number} obj.color.saturation between 0 and 65535
 * @param  {Number} obj.color.brightness between 0 and 65535
 * @param  {Number} obj.color.kelvin between 2500 and 9000
 * @param  {Number} [obj.duration] transition time in milliseconds
 * @param  {Number} obj.apply value 0 (NO_APPLY), 1 (APPLY) or 2 (APPLY_ONLY)
 * @return {Buffer} packet
 */
Packet.toBuffer = function(obj) {
  const buf = Buffer.alloc(this.size);
  buf.fill(0);
  let offset = 0;

  if (typeof obj.startIndex !== 'number' && obj.startIndex < 0 || obj.startIndex > 255) {
    throw new RangeError('Invalid startIndex value given for setColorZones LIFX packet, must be a number between 0 and 255');
  }
  buf.writeUInt8(obj.startIndex, offset);
  offset += 1;

  if (typeof obj.endIndex !== 'number' && obj.endIndex < 0 || obj.endIndex > 255) {
    throw new RangeError('Invalid endIndex value given for setColorZones LIFX packet, must be a number between 0 and 255');
  }
  buf.writeUInt8(obj.endIndex, offset);
  offset += 1;

  if (typeof obj.hue !== 'number' || obj.hue < 0 || obj.hue > 65535) {
    throw new RangeError('Invalid color hue given for setColorZones LIFX packet, must be a number between 0 and 65535');
  }
  buf.writeUInt16LE(obj.hue, offset);
  offset += 2;

  if (typeof obj.saturation !== 'number' || obj.saturation < 0 || obj.saturation > 65535) {
    throw new RangeError('Invalid color saturation given for setColorZones LIFX packet, must be a number between 0 and 65535');
  }
  buf.writeUInt16LE(obj.saturation, offset);
  offset += 2;

  if (typeof obj.brightness !== 'number' || obj.brightness < 0 || obj.brightness > 65535) {
    throw new RangeError('Invalid color brightness given for setColorZones LIFX packet, must be a number between 0 and 65535');
  }
  buf.writeUInt16LE(obj.brightness, offset);
  offset += 2;

  if (obj.kelvin === undefined) {
    obj.kelvin = constants.HSBK_DEFAULT_KELVIN;
  }
  if (typeof obj.kelvin !== 'number' && obj.kelvin < 2500 || obj.kelvin > 9000) {
    throw new RangeError('Invalid color kelvin given for setColorZones LIFX packet, must be a number between 2500 and 9000');
  }
  buf.writeUInt16LE(obj.kelvin, offset);
  offset += 2;

  // Duration is 0 by default
  if (obj.duration !== undefined) {
    buf.writeUInt32LE(obj.duration, offset);
  }
  offset += 4;

  if (obj.apply === undefined) {
    throw new TypeError('obj.apply value must be given for setColorZones LIFX packet');
  }
  if (typeof obj.apply !== 'number' && obj.apply < 0 || obj.apply > 2) {
    throw new RangeError('Invalid apply value given for setColorZones LIFX packet, must be a number between 0 and 2');
  }
  buf.writeUInt8(obj.apply, offset);
  offset += 1;

  return buf;
};

module.exports = Packet;