package test;

import java.io.*;
import java.net.*;
import java.util.Date;
import java.text.DateFormat;
import java.util.Random;

public class client {

    Socket s;
    int pauseMillisMin, pauseMillisMax;
    int msgLen;
    String msg;

    Random rand = new Random();

    public client(InetAddress host, int sport, int pauseMillisMin, int pauseMillisMax, int msgLen)
	throws IOException
    {
	s = new Socket(host, sport);
	this.pauseMillisMin = pauseMillisMin;
	this.pauseMillisMax = pauseMillisMax;
	this.msgLen = msgLen;
	StringBuffer sb = new StringBuffer(msgLen+1);
	for (int i = 0; i < msgLen; i++)
	    sb.append((char) (33 + Math.random()*93));
	sb.append("\n");
	msg = sb.toString();
	(new Thread(new MyWriter(s.getOutputStream()))).start();
	(new Thread(new MyReader(s.getInputStream()))).start();
    }

    class MyWriter implements Runnable {
	OutputStream so;
	int pauseMillisSpread = 1 + pauseMillisMax - pauseMillisMin;
	MyWriter(OutputStream so) {this.so = so;}
	public void run() {
	    OutputStreamWriter osr = new OutputStreamWriter(so);
	    try {
		while (true) {
		    osr.write(msg);
		    int pauseMillis = pauseMillisMin;
		    if (pauseMillisSpread > 1)
			pauseMillis += rand.nextInt(pauseMillisSpread);
		    try {
			Thread.sleep(pauseMillis);
		    } catch (Exception ex) {}
		}
	    } catch (IOException ex) {
		int locport = s.getLocalPort();
		System.err.println("At " + nowString()
				   + ", aborting writing from " + locport
				   + " because of exn " + ex.getClass().getName()
				   + " msg=" + ex.getMessage());
	    }
	}
    }
    
    class MyReader implements Runnable {
	InputStream si;
	MyReader(InputStream si) {this.si = si;}
	public void run() {
	    InputStreamReader isr = new InputStreamReader(si);
	    BufferedReader br = new BufferedReader(isr);
	    try {
		while (true) {
		    String mr = br.readLine();
		    if (!msg.regionMatches(0, mr, 0, msgLen)) {
			System.err.println("Message mismatch!  Sent ["
					   + msg + "] received ["
					   + mr + "].");
			return;
		    }
		}
	    } catch (IOException ex) {
		int locport = s.getLocalPort();
		System.err.println("At " + nowString()
				   + ", aborting reading through " + locport
				   + " because of exn " + ex.getClass().getName()
				   + " msg=" + ex.getMessage());
	    }
	}
    }
    
    public static void main(String[] args) throws IOException {
	if (args.length != 6) {
	    System.err.println("Usage: client host port nThreads pauseMillisMin pauseMillisMax msgLen");
	    System.exit(1);
	}
	String hostStr = args[0];
	int sport = Integer.parseInt(args[1]);
	int nThreads = Integer.parseInt(args[2]);
	int pauseMillisMin = Integer.parseInt(args[3]);
	int pauseMillisMax = Integer.parseInt(args[4]);
	int msgLen = Integer.parseInt(args[5]);
	InetAddress host = InetAddress.getByName(hostStr);
	System.out.println("Testing host " + host
			   + ", port " + sport
			   + ", n-thds=" + nThreads
			   + ", pause-ms=[" + pauseMillisMin
			   + ", " + pauseMillisMax + "]"
			   + ", msglen=" + msgLen);
	for (int i = 0; i < nThreads; i++) {
	    new client(host, sport, pauseMillisMin, pauseMillisMax, msgLen);
	}
	System.out.println("Started at " + nowString());
    }

    private static final DateFormat df = DateFormat.getDateTimeInstance(DateFormat.FULL,
									DateFormat.FULL);

    private static String nowString() {
        Date dNow = new Date();
        return df.format(dNow);
    }
    
}