/// <summary>
/// Questo metodo conferma o rifiuta la ricezione di un file da parte di un host remoto.
/// Seguito dalla conferma ci sarà il nome del file su cui è stata fatta la scelta
/// </summary>
/// <param name="ip">Ip dell'host su cui si è eseguita la scelta</param>
/// <param name="type">La scela effettuata</param>
public async Task SendResponse(string ip, string nameFile, PacketType type)
{
if (type != PacketType.YFILE && type != PacketType.NFILE)
{
return;
}
if (!_referenceData.UpdateStatusRecvFileForUser(ip, nameFile, type == PacketType.YFILE ? FileRecvStatus.YSEND : FileRecvStatus.NSEND))
{
throw new Exception("File don't exists in collection");
}
int attempts = 0;
// In case of exception resend the packet three times
do
{
TcpClient client = null;
NetworkStream stream = null;
try {
attempts++;
client = new TcpClient();
await client.ConnectAsync(ip, SharedInfo.TCPPort).ConfigureAwait(false);
byte[] bytes = new byte[1 + 256];
bytes[0] = (byte)type;
UTF8Encoding encorder = new UTF8Encoding();
encorder.GetBytes(nameFile).CopyTo(bytes, 1);
stream = client.GetStream();
await stream.WriteAsync(bytes, 0, 257).ConfigureAwait(false);
break;
}
catch (SocketException e) {
Console.WriteLine($"{DateTime.Now.ToString()}\t - SocketException on SendResponse - {e.Message}");
// If the remote host was offline, try to resend it for three times
if (_referenceData.GetUserStatus(ip).Equals("offline"))
{
break;
}
else if (attempts == 3)
{
break;
}
else
{
await Task.Delay(10).ConfigureAwait(false);
}
}
catch (Exception e) {
Console.WriteLine($"{DateTime.Now.ToString()}\t - Exception on SendResponse - {e.Message}");
if (attempts == 3)
{
break;
}
else
{
await Task.Delay(10).ConfigureAwait(false);
}
}
finally {
client.Close();
stream.Close();
}
if (attempts == 3 && _referenceData.GetUserStatus(ip).Equals("offline"))
{
break;
}
} while (true);
}
