/*
 * Copyright (c) 1995, 1996 Sun Microsystems, Inc. All Rights Reserved.
 *
 * Permission to use, copy, modify, and distribute this software
 * and its documentation for NON-COMMERCIAL purposes and without
 * fee is hereby granted provided that this copyright notice
 * appears in all copies. Please refer to the file "copyright.html"
 * for further important copyright and licensing information.
 *
 * SUN MAKES NO REPRESENTATIONS OR WARRANTIES ABOUT THE SUITABILITY OF
 * THE SOFTWARE, EITHER EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED
 * TO THE IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
 * PARTICULAR PURPOSE, OR NON-INFRINGEMENT. SUN SHALL NOT BE LIABLE FOR
 * ANY DAMAGES SUFFERED BY LICENSEE AS A RESULT OF USING, MODIFYING OR
 * DISTRIBUTING THIS SOFTWARE OR ITS DERIVATIVES.
 */
import java.io.*;
import java.net.*;
import java.util.*;

class QuoteServerThread extends Thread {
    private DatagramSocket socket = null;
    private DataInputStream qfs = null;

    QuoteServerThread() {
	super("QuoteServer");
	try {
	    socket = new DatagramSocket();
	    System.out.println("QuoteServer listening on port: " + socket.getLocalPort());
	} catch (java.net.SocketException e) {
	    System.err.println("Could not create datagram socket.");
        }
	this.openInputFile();
    }

    public void run() {
	if (socket == null)
	    return;

	while (true) {
	    try {
	        byte[] buf = new byte[256];
	        DatagramPacket packet;
	        InetAddress address;
	        int port;
	        String dString = null;

		    // receive request
	        packet = new DatagramPacket(buf, 256);
                socket.receive(packet);
	        address = packet.getAddress();
	        port = packet.getPort();

		    // send response
		if (qfs == null)
	            dString = new Date().toString();
		else
	            dString = getNextQuote();
	        dString.getBytes(0, dString.length(), buf, 0);
	        packet = new DatagramPacket(buf, buf.length, address, port);
	        socket.send(packet);
	    } catch (Exception e) {
	        System.err.println("Exception:  " + e);
	        e.printStackTrace();
	    }
	}
    }
    protected void finalize() {
	if (socket != null) {
	    socket.close();
	    socket = null;
	    System.out.println("Closing datagram socket.");
	}
    }

    private void openInputFile() {
        try {
	    qfs = new DataInputStream(new FileInputStream("one-liners"));
	} catch (java.io.FileNotFoundException e) {
	    System.err.println("Could not open quote file. Serving time instead.");
	}
    }
    private String getNextQuote() {
	String returnValue = null;
        try {
	    if ((returnValue = qfs.readLine()) == null) {
	        qfs.close();
	        this.openInputFile();
	        returnValue = qfs.readLine();    // we know the file has at least one input line!
	    }
        } catch (IOException e) {
	    returnValue = "IOException occurred in server.";
        }
	return returnValue;
    }

}