private static byte[] GetOptions(IEnumerable<Option> options)
{
var writer = new DatagramWriter();
var lastOptionNumber = 0;
foreach (var option in options) {
var delta = (int) option.Number - lastOptionNumber;
var length = option.Value.Length;
if (length <= Message.MaxOptionLengthBase) {
writer.Write(delta, Message.OptionDeltaBits);
writer.Write(length, Message.OptionLengthBits);
}
else {
const int baseLength = Message.MaxOptionLengthBase + 1;
writer.Write(delta, Message.OptionDeltaBits);
writer.Write(baseLength, Message.OptionLengthBits);
writer.Write(length - baseLength, Message.OptionLengthExtendedBits);
}
writer.WriteBytes(option.Value);
lastOptionNumber = (int) option.Number;
}
return writer.GetBytes();
}
public virtual byte[] Serialize(Message message)
{
var writer = new DatagramWriter();
writer.Write(Message.Version, Message.VersionBits);
writer.Write((int) message.Type, Message.TypeBits);
writer.Write(message.OptionCount, Message.OptionCountBits);
writer.Write((int) message.Code, Message.CodeBits);
writer.Write(message.Id, Message.IdBits);
writer.WriteBytes(GetOptions(message.Options));
writer.WriteBytes(message.Payload);
return writer.GetBytes();
}
public void Should_throw_exception_when_version_is_incorrect()
{
var writer = new DatagramWriter();
writer.Write(0, Message.VersionBits);
writer.Write((int) MessageType.Confirmable, Message.TypeBits);
writer.Write(0, Message.OptionCountBits);
writer.Write((int) CodeRegistry.Get, Message.CodeBits);
writer.Write(1, Message.IdBits);
var bytes = writer.GetBytes();
_serializer.Deserialize(bytes);
}