Milesight VS360: LoRaWAN IR Breakbeam People Counter

function decodeUplink(input) {
  var bytes = input.bytes;
  var data = {};

  for (var i = 0; i < bytes.length; ) {
    var channel = bytes[i++];
    var type = bytes[i++];

    // Device info on join / power-on (protocol, hw/fw, serial, class)
    if (channel === 0xff) {
      if (type === 0x01) { i += 1; }        // IPSO version
      else if (type === 0x09) { i += 2; }   // hardware version
      else if (type === 0x0a) { i += 2; }   // firmware version
      else if (type === 0x16) { i += 8; }   // serial number
      else if (type === 0x0f) { i += 1; }   // LoRaWAN class
      else if (type === 0xff) { i += 2; }   // TSL version
      else { break; }
    } else if (channel === 0x01 && type === 0x75) {        // battery master (%)
      data.battery_main = bytes[i]; i += 1;
    } else if (channel === 0x02 && type === 0x75) {        // battery node (%)
      data.battery_node = bytes[i]; i += 1;
    } else if (channel === 0x03 && type === 0xf4) {        // event: type + status
      data.event = { type: bytes[i], status: bytes[i + 1] }; i += 2;
    } else if (channel === 0x04 && type === 0xcc) {        // total in / out
      data.total_in = readUInt16LE(bytes, i);
      data.total_out = readUInt16LE(bytes, i + 2); i += 4;
    } else if (channel === 0x84 && type === 0xcc) {        // total in / out + alarm
      data.total_in = readUInt16LE(bytes, i);
      data.total_out = readUInt16LE(bytes, i + 2);
      data.total_count_alarm = bytes[i + 4]; i += 5;
    } else if (channel === 0x05 && type === 0xcc) {        // period in / out
      data.period_in = readUInt16LE(bytes, i);
      data.period_out = readUInt16LE(bytes, i + 2); i += 4;
    } else if (channel === 0x85 && type === 0xcc) {        // period in / out + alarm
      data.period_in = readUInt16LE(bytes, i);
      data.period_out = readUInt16LE(bytes, i + 2);
      data.period_count_alarm = bytes[i + 4]; i += 5;
    } else if (channel === 0x0a && type === 0xef) {        // timestamp (UINT32LE)
      data.timestamp = readUInt32LE(bytes, i); i += 4;
    } else {
      break;
    }
  }
  return { data: data };
}

function readUInt16LE(b, i) {
  return (b[i + 1] << 8) | b[i];
}
function readUInt32LE(b, i) {
  return ((b[i + 3] << 24) | (b[i + 2] << 16) | (b[i + 1] << 8) | b[i]) >>> 0;
}