package perf;

import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.net.DatagramPacket;
import java.net.DatagramSocket;
import java.net.InetAddress;
import java.net.SocketTimeoutException;
import java.text.DateFormat;
import java.text.SimpleDateFormat;
import java.util.Date;

class UDPPerfClient {
	public static void main(String argv[]) throws Exception {
		String hostname = "";
		int udpPort = 36039;
		DateFormat df = new SimpleDateFormat("dd.MM.yyyy HH:mm:ss");

		//System.out.println("Bitte geben Sie die Server-Adresse ein: ");
		//hostname = inFromUser.readLine();
		hostname = "127.0.0.1";
		InetAddress serverAddress = InetAddress.getByName(hostname);

		while (true) {
			BufferedReader inFromUser = new BufferedReader(new InputStreamReader(System.in));
			System.out.print("Bitte geben Sie die Anzahl zu übertragender Megabytes ein: ");
			Long numberOfMegabytes = new Long(inFromUser.readLine());
			//Long number = (long)1;
			
			DatagramSocket clientSocket = new DatagramSocket();
			clientSocket.setSoTimeout(5000);

			long timestampStart = System.currentTimeMillis();
			System.out.println("Zeit vor Versand = " + timestampStart + " ms, " + df.format(new Date(timestampStart)));
			byte[] outbuffer = (new String(numberOfMegabytes + "\n")).getBytes();
			DatagramPacket sendPacket = new DatagramPacket(outbuffer, outbuffer.length, serverAddress, udpPort);
			clientSocket.send(sendPacket);
			
			if (numberOfMegabytes == 0) {
				break;
			}

			long totalBytesReceived = 0;
			while (true) {
				byte[] receiveData = new byte[1024];
				DatagramPacket receivePacket = new DatagramPacket(receiveData, receiveData.length);
				try {
					clientSocket.receive(receivePacket);
				} catch (SocketTimeoutException ste) {
					System.out.println("Timeout");
					break;
				}

				String receivedString = new String(receiveData);
				if (receivedString.contains("done")) {
					System.out.println("Ende der Übermittlung erkannt.");
					break;
				}
				else
				{
					totalBytesReceived += receivePacket.getLength();
					System.out.println(totalBytesReceived + " Bytes insgesamt empfangen.");
				}

			}
			System.out.printf("Insgesamt %d Bytes von %d (%d MB) empfangen.\n", totalBytesReceived - 4, (1024 * 1024) * numberOfMegabytes, numberOfMegabytes);
			clientSocket.close();
		}
	}
}