import java.lang.*;
import java.net.*;
import java.io.*;
import java.awt.*;

public class extractor {

  final static int END = 9999999;

  public static void main(String argv[]) {
    int from, to;
    boolean fail = false;

    if (argv.length < 3 || argv.length > 4) {
      System.err.
	println("Syntax: extractor <recording> <extract> <from#> [<to#>]");
      System.exit(1);
    }

    from = 0;
    try {
      from = Integer.parseInt(argv[2]);
    } catch (NumberFormatException ex) { 
      fail = true;
    }
    if (fail || from < 0) {
      System.err.println("Bad argument 3. Should be a positive integer.");
      System.exit(1);
    }

    to = END;
    if (argv.length > 3) 
      try {
	to = Integer.parseInt(argv[3]);
      } catch (NumberFormatException ex) { 
	fail = true;
      }
    if (fail || to <= from) {
      System.err.println("Bad argument 4. Should be a positive integer.");
      System.exit(1);
    }

    NetrekGame game = new NetrekGame();
    game.disable();

    RandomAccessFile infile = null;
    try {
      infile = new RandomAccessFile(argv[0], "r");
    } catch (IOException ex) {
      System.err.println("Cannot open file " + argv[0]);
      System.exit(1);
    }

    DataOutput outdata = null;
    try {
      outdata = new DataOutputStream(new FileOutputStream(argv[1]));
    } catch (IOException ex) {
      System.err.println("Cannot create file " + argv[1]);
      System.exit(1);
    }

    long start = 0, end = 0;
    int packet = 0;
    boolean ok = true;
    while (packet < from && ok) {
      ok = game.step(infile);
      packet++;
    }
    if (!ok) {
      System.err.println("Recording ends before packet " + from);
      System.exit(1);
    }
    System.err.println("Found beginning...");
    try {
      start = infile.getFilePointer();
    } catch (IOException ex) {
      System.err.println("Ooops... cannot find first file pos...");
      System.exit(1);
    }
    System.out.println(start);

    if (start > 0) try {
      game.DumpStateInit(outdata);
      game.DumpState(outdata);
    } catch (IOException ex) {
      System.err.println("Ooops... cannot dump inital state...");
      System.exit(1);
    }

    if (to == END)
      try end = infile.length(); catch (IOException ex) { }
    else  {
      while (packet < to && ok) {
	ok = game.step(infile);
	packet++;
      }
      try {
	end = infile.getFilePointer();
      } catch (IOException ex) {
	System.err.println("Ooops... cannot find second file pos...");
	System.exit(1);
      }
      System.err.println("Found end...");
    }
    System.out.println(end);
    
    try {
      infile.seek(start);
      byte buf[] = new byte[(int) (end - start)];
      infile.readFully(buf);
      outdata.write(buf, 0, buf.length);
    } catch (IOException ex) {
      System.err.println("Ooops... could not perform extraction...");
      System.exit(1);
    }
    System.err.println("Done...");
    System.exit(0);
  }
}