/*
                 WWWWW : The Wholly Wholesome World Wide Web

             Delivering only wholesome web pages to your house ...
*/

import java.io.*;
import java.net.*;
import java.util.*;

public class wwwww
{
  static final int SERVERPORT = 8010;

  public static void main(String args[]) throws Exception
    { 
      ServerSocket sfd;
      Socket cfd, pfd;
      DataInputStream din, pin;
      DataOutputStream dout, pout;
      String s;
      String rsname = "localhost"; // name of remote server
      int rsport = 80; // default port of remote server
      sfd = new ServerSocket(SERVERPORT);
      sfd.setReuseAddress(true); // for debugging

      byte[] inbuf = new byte[1500];
      byte[] outbuf = new byte[1500];

      while (true)
      {
        cfd = sfd.accept();  
	cfd.setSoTimeout(8000); // 8 second read timeout
        System.out.print("wwwww: connect from "+cfd.getInetAddress()+", ");
	pfd = null;

        try 
	{
	    din = new DataInputStream(cfd.getInputStream());   // using binary io
	    dout = new DataOutputStream(cfd.getOutputStream());  // to be sure

	  // parse request to retrieve destination URL:
	  // "request comes in the form GET http://URL " - for this example
          // we wont' go into the details of parsing.

	    int rb = din.read(inbuf,0,1500);
	    String DURL = myutils.bufToString(inbuf,0,rb);
	    //System.out.println("wwwww: 1st line: "+DURL); //trace
	    StringTokenizer st = new StringTokenizer(DURL," \t\n:/",true); // parsing
	  s = st.nextToken();
	  if (!s.equals("GET")) throw new Exception("format error");
	  s = st.nextToken(); s=st.nextToken(); // skip space
	  if (!s.equals("http")) throw new Exception("protocol not supported");
	  st.nextToken(); st.nextToken(); st.nextToken(); // skip "://"
	  rsname = st.nextToken();

	  String colon = st.nextToken();
	  if (colon.equals(":")) rsport = Integer.parseInt(st.nextToken());

	  System.out.println("hwwwww: remote server: "+rsname+":"+rsport);  // trace

	  // open socket to remote server (the proxy socket)
	  pfd = new Socket(rsname,rsport);

	  System.out.printf("pfd opened to %s:%d\n",rsname,rsport); System.out.flush();
	  pfd.setSoTimeout(8000); // 8 second read timeout
	  //rsname = "localhost"; rsport = 80; // restore defaults

	  pin = new DataInputStream(pfd.getInputStream());
	  pout = new DataOutputStream(pfd.getOutputStream());

	  //myutils.stringToBuf(outbuf,DURL,0);
	  pout.write(inbuf,0,rb); pout.flush();   // relay exactly what was received
	  
	  // begin relay threads:
	  Thread AB = new Thread(new rthread(din,pout,cfd));
	  Thread BA = new Thread(new rthread(pin,dout,pfd));
	  AB.start();
	  BA.start();
	  BA.join();
	  AB.join();

          System.out.println("connection from "+cfd.getInetAddress()+" terminated");
	  pfd.close(); cfd.close();
        } catch (Exception e) 
	    {System.out.println(e); cfd.close(); pfd.close();}
      } // while
    }  // main
} // wwwww class

// a thread that relay info in one direction:
class rthread implements Runnable
{
    // We don't relay bad words!
    String makewholesome(String s)
    {
	s = s.replaceAll("damn ","darn ");
	s = s.replaceAll("hell ","heck ");
	s = s.replaceAll("Liang is evil","It's not Liang's fault");
	return s;
    } // make the world wholly wholesome!

    DataInputStream din;
    DataOutputStream dout;
    Socket stoclose; // the socket to close
    byte[] inbuf = new byte[1500];
    byte[] outbuf = new byte[1500];

    public rthread(DataInputStream b, DataOutputStream p, Socket sc)
    { din=b;  dout=p; stoclose=sc; }
    
    private void serve() throws Exception
    { String s = "ab";
      
      try 
      {
	  while (s!=null)
	      {
		  int rb = din.read(inbuf,0,1500);
		  s = myutils.bufToString(inbuf,0,rb);
      		  //s = br.readLine();
		  //System.out.println("RT: "+s);  //trace
	       	  if (s!=null) s = makewholesome(s);
		  if (s!=null) myutils.StringToBuf(inbuf,s,0);
		  dout.write(inbuf,0,rb);
		  dout.flush();
	      }
      } catch (Exception e) { din.close(); dout.close(); stoclose.close(); } 
    }

    public void run()
    { 
	try 
        {
	    serve();
	} catch (Exception e) {}
    }
}  // rthread

/*
  This program was created for educational purposes only.
*/