// File: PVWaveAccessServer.java
//
// Author: Francois Coupleux (coupleux@eleve.emn.fr)
//
// Date: 7-29-1996
//
// Description: Server which sends commands to PV-Wave.

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

class PVWaveAccessServer
{
  public static void main(String arg[])
  {
    ServerSocket serverSocket;
    Socket clientSocket;
    DataInputStream dataInputStream , currentInputStream;
    PrintStream dataOutputStream , currentOutputStream;
    Vector ids , currentVector , x1 , y1 , x2 , y2;
    String message , currentClientId , command;
    StringTokenizer stringTokenizer;
    URL pvWaveServerURL;
    URLConnection pvWaveServerConnection;
    File imageFile , standardImageFile;
    int i;

    try
    {
      // Creates vectors

      ids = new Vector();
      x1 = new Vector();
      y1 = new Vector();
      x2 = new Vector();
      y2 = new Vector();

      pvWaveServerConnection = null;

      // Creates sockets

      serverSocket = new ServerSocket(7000);

      while(true)
      {
        // Waits for a client

        clientSocket = serverSocket.accept();

        // Creates streams

        dataInputStream = new DataInputStream(clientSocket.getInputStream());
        dataOutputStream = new PrintStream(clientSocket.getOutputStream());

        while(true)
        {
          // Waits for a message from the client

          while((message = dataInputStream.readLine()) == null)
          {
            ;
          }

          stringTokenizer = new StringTokenizer(message , "&");

          currentClientId = stringTokenizer.nextToken();

          // Declares a new client

          for(i = 0 ; i < ids.size() ; i++)
          {
            if(((String)ids.elementAt(i)).equals(currentClientId))
            {
              break;
            }
          }

          if(i == ids.size())
          {
            ids.addElement(currentClientId);
            x1.addElement("0");
            y1.addElement("0");
            x2.addElement("0");
            y2.addElement("0");
          }

          // Creates streams to the PV-Wave server

          pvWaveServerURL = new URL("http://www.jwave.vt.edu/cgi-bin/call_wave_visualizer");
          pvWaveServerConnection = pvWaveServerURL.openConnection();

          currentOutputStream = new PrintStream(pvWaveServerConnection.getOutputStream());

          command = stringTokenizer.nextToken();

          // If the comman is an OPLOT command this sets the clipping area

          if(command.startsWith("OPLOT"))
          {
            for(i = 0 ; i < ids.size() ; i++)
            {
              if(((String)ids.elementAt(i)).equals(currentClientId))
              {
                break;
              }
            }

            currentOutputStream.println("clipping_area(0)=" + (String)x1.elementAt(i));
            currentOutputStream.close();
            currentInputStream = new DataInputStream(pvWaveServerConnection.getInputStream());
            while(currentInputStream.readLine() == null)
            {
              ;
            }
            currentInputStream.close();

            pvWaveServerURL = new URL("http://www.jwave.vt.edu/cgi-bin/call_wave_visualizer");
            pvWaveServerConnection = pvWaveServerURL.openConnection();

            currentOutputStream = new PrintStream(pvWaveServerConnection.getOutputStream());
            currentOutputStream.println("clipping_area(1)=" + (String)y1.elementAt(i));
            currentOutputStream.close();
            currentInputStream = new DataInputStream(pvWaveServerConnection.getInputStream());
            while(currentInputStream.readLine() == null)
            {
              ;
            }
            currentInputStream.close();

            pvWaveServerURL = new URL("http://www.jwave.vt.edu/cgi-bin/call_wave_visualizer");
            pvWaveServerConnection = pvWaveServerURL.openConnection();

            currentOutputStream = new PrintStream(pvWaveServerConnection.getOutputStream());
            currentOutputStream.println("clipping_area(2)=" + (String)x2.elementAt(i));
            currentOutputStream.close();
            currentInputStream = new DataInputStream(pvWaveServerConnection.getInputStream());
            while(currentInputStream.readLine() == null)
            {
              ;
            }
            currentInputStream.close();

            pvWaveServerURL = new URL("http://www.jwave.vt.edu/cgi-bin/call_wave_visualizer");
            pvWaveServerConnection = pvWaveServerURL.openConnection();

            currentOutputStream = new PrintStream(pvWaveServerConnection.getOutputStream());
            currentOutputStream.println("clipping_area(3)=" + (String)y2.elementAt(i));
            currentOutputStream.close();
            currentInputStream = new DataInputStream(pvWaveServerConnection.getInputStream());
            while(currentInputStream.readLine() == null)
            {
              ;
            }
            currentInputStream.close();

            pvWaveServerURL = new URL("http://www.jwave.vt.edu/cgi-bin/call_wave_visualizer");
            pvWaveServerConnection = pvWaveServerURL.openConnection();

            currentOutputStream = new PrintStream(pvWaveServerConnection.getOutputStream());
          }

          // Sends the message to PV-Wave

          currentOutputStream.println(command);

          currentOutputStream.close();

          currentInputStream = new DataInputStream(pvWaveServerConnection.getInputStream());

          // Waits for the PV_Wave response

          while((message = currentInputStream.readLine()) == null)
          {
            ;
          }

          if(message.charAt(0) == '[')
          {
            while((message = currentInputStream.readLine()) == null)
            {
              ;
            }
          }

          // If it's an EXIT or a QUIT message

          if(message.equals("Bye-bye, leaving PV-WAVE..."))
          {
            // Deletes the image

            imageFile = new File("/home3/httpd/htdocs/javaprj/viscprj/visualizer/applet/PVWaveGraphs" , currentClientId);
            imageFile.delete();

            // Sends the message to the applet

            dataOutputStream.println(message);

            // Closes connections to the PV-Wave server

            currentInputStream.close();

            break;
          }

          // If it's a message about clipping area

          else if(message.startsWith("WAVE> PRINT"))
          {
            // Gets the correct vector for the clipping value

            stringTokenizer = new StringTokenizer(message , "(");
            stringTokenizer.nextToken();

            switch(stringTokenizer.nextToken().charAt(0))
            {
              case '0': currentVector = x1;
                        break;
              case '1': currentVector = y1;
                        break;
              case '2': currentVector = x2;
                        break;
              default:  currentVector = y2;
                        break;
            }

            // Puts the clipping value in the vector

            for(i = 0 ; i < ids.size() ; i++)
            {
              if(((String)ids.elementAt(i)).equals(currentClientId))
              {
                break;
              }
            }

            stringTokenizer = new StringTokenizer(currentInputStream.readLine() , " ");
            currentVector.setElementAt(stringTokenizer.nextToken() , i);

            // Sends the message to the applet

            dataOutputStream.println(message);
          }

          else
          {
            // If it's the REDRAW message

            if(message.startsWith("WAVE> PLOT") || message.startsWith("WAVE> OPLOT"))
            {
              // Renames the file "graph.gif"

              imageFile = new File("/home3/httpd/htdocs/javaprj/viscprj/visualizer/applet/PVWaveGraphs" , currentClientId);
              imageFile.delete();
              standardImageFile = new File("/home3/httpd/htdocs/javaprj/viscprj/visualizer/applet/PVWaveGraphs" , "graph.gif");
              standardImageFile.renameTo(imageFile);
            }

            // Sends the message to the applet

            dataOutputStream.println(message);

            if(message.startsWith("WAVE> PLOT") || message.startsWith("WAVE> OPLOT"))
            {
              break;
            }
          }
        }

        // Closes connection to the client and client's socket

        dataInputStream.close();
        clientSocket.close();
      }
    }
    catch(Exception exception)
    {
      System.out.println("Error: Impossible to run the PVWaveAccessServer.");
    }
  }
}