public ArraySegment <byte> Serialize(MqttBasePacket packet)
{
if (packet == null)
{
throw new ArgumentNullException(nameof(packet));
}
// Leave enough head space for max header size (fixed + 4 variable remaining length = 5 bytes)
_packetWriter.Reset();
_packetWriter.Seek(5);
var fixedHeader = SerializePacket(packet, _packetWriter);
var remainingLength = _packetWriter.Length - 5;
var remainingLengthBuffer = MqttPacketWriter.EncodeRemainingLength(remainingLength);
var headerSize = FixedHeaderSize + remainingLengthBuffer.Count;
var headerOffset = 5 - headerSize;
// Position cursor on correct offset on beginining of array (has leading 0x0)
_packetWriter.Seek(headerOffset);
_packetWriter.Write(fixedHeader);
_packetWriter.Write(remainingLengthBuffer.Array, remainingLengthBuffer.Offset, remainingLengthBuffer.Count);
var buffer = _packetWriter.GetBuffer();
return(new ArraySegment <byte>(buffer, headerOffset, _packetWriter.Length - headerOffset));
}
