protected async UniTask HandshakeAsync(int bits)
{
// in the very first message we must mine a hashcash token
// and send that as a hello
// the server won't accept connections otherwise
string applicationName = Application.productName;
HashCash token = await UniTask.RunOnThreadPool(() => HashCash.Mine(applicationName, bits));
byte[] hello = new byte[1000];
int length = HashCashEncoding.Encode(hello, 0, token);
var data = new ArraySegment <byte>(hello, 0, length);
// send a greeting and see if the server replies
await SendAsync(data);
var stream = new MemoryStream();
try
{
await ReceiveAsync(stream);
}
catch (Exception e)
{
throw new InvalidDataException("Unable to establish connection, no Handshake message received.", e);
}
}
// calculate the hash of a hashcash token
private byte[] Hash(HashAlgorithm hashAlgorithm, byte[] buffer)
{
int length = HashCashEncoding.Encode(buffer, 0, this);
return(hashAlgorithm.ComputeHash(buffer, 0, length));
}