/*
                 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 wwwww2
{
  static final int SERVERPORT = 8011;

  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;  // proxy socket

        try 
	{
	    din = new DataInputStream(cfd.getInputStream());
	    dout = new DataOutputStream(cfd.getOutputStream());

	  // 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);
	  s = "abc";
	  s = st.nextToken();
	  //	  if (!s.equals("GET"))
	  //          throw new Exception("format error: "+s);
	  while (!s.equals("GET")) 
	      {   System.out.print(s+ " ");
		  s = st.nextToken();
	      }
          System.out.println(s+ " received");
	  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);

	  // 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
	  
	  //	  pw.print("HTTP/1.1 200 OK\n\0");  pw.flush();  // send preamble to client

	  // begin relay threads:
	  Thread AB = new Thread(new rthread(din,pout,cfd,false));
	  Thread BA = new Thread(new rthread(pin,dout,pfd,true));
	  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
{
    boolean zflag = false;   // zero-terminated strings
    boolean censor = false;  // not needed each way.


    // We don't relay bad words!  --- MAKE IT WHOLESOME!
    String makewholesome(String s)
    {
	s = s.replaceAll("damn ","darn ");  // no unwholesome content on the wwwww!
	s = s.replaceAll("hell ","heck ");
	s = s.replaceAll("Satan","XXXXX");  // blot out Satan and his followers ...
	s = s.replaceAll("Liang","XXXXX");  
	return s;
    }// make the whole wide 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, boolean c)
    { din=b;  dout=p; stoclose=sc; censor=c;}
    
    private void serve() throws Exception
    { String s = "ab";
      int len = 0;
      int rb = 1;
      int inclen = 0;
      try 
      {
	  while (rb>0)  // (s!=null)
	      {
		  rb = din.read(inbuf,0,1500);
		  if (rb>0) s = myutils.bufToString(inbuf,0,rb); 
		  else s=null;
		  if (s!=null) len = s.length();  else len=0;
	       	  if (s!=null && censor) s = makewholesome(s);
		  if (s!=null) myutils.StringToBuf(inbuf,s,0);
		  if (rb>0) dout.write(inbuf,0,rb+inclen);
		  //pw.println(s); 
		  //if (zflag) { pw.print("\0"); zflag = false;}
		  dout.flush();
	      }
	  //	  System.out.println("thread exiting ..."); System.out.flush();
      } catch (Exception e) { din.close(); dout.close(); stoclose.close(); System.out.println(e);} 
    }

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

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