// H4Replace.java
//
// You may use and distribute this example. This program is 
// provided WITHOUT WARRANTY either expressed or implied.
//
// Copyright Henrik Björkman 1997
//
// This program is about the same as H2Replace. The new 
// functionality is that this program will get the names
// of the files to process from a file.
//
//
// This program uses Piped Input and Output Streams to send a 
// stream of data through a number of filter programs. Each of 
// these filter programs is a thread reading from an input and 
// writing to an output stream. For the first filter the input 
// is a file and for the last the output is system out.
//
// History:
// 0.0 Created by Henrik Björkman 1997-12-03 
//     (using code from H2Replace.java)
// 0.1 Added package. Henrik 1998-01-25
// 0.2 Using se.beod.henrik.filter.*. Henrik 1998-06-06



import java.io.*;
import se.beod.henrik.filter.*;



public class H4Replace
{
  PipedInputStream in=null;
  PipedOutputStream out=null;
  PipedInputStream next_in=null;

  static void error(String str)
  {
    System.err.println("H4Replace: " + str);
  }

  static void debug(String str)
  {
    error(str);
  }

  // This function is called before each filter thread is created
  // To create an input output pair of piped stream and set up the
  // in and out to be used by the filter thread to be started.
  void setupInOut() throws IOException
  {
    in=next_in;
    out=new PipedOutputStream();
    next_in=new PipedInputStream(out);
  }

  public H4Replace(FilterDB db, String in_file_name, String out_file_name)
  {
    Thread last_thread=null;

    debug("in " + in_file_name + " out " + out_file_name);

    try 
    {
      setupInOut();
      new WordParse(new FileInputStream(in_file_name),out);

      setupInOut();
      new MultiReplacer(in,out,db);

      setupInOut();
      last_thread=new LineMerge(in,new FileOutputStream(out_file_name));  

      try 
      {
        /* Now just wait for the last thread to finish (or die) */
        last_thread.join();
      }
      catch (InterruptedException e) {error(""+e);}
    }
    catch (IOException e) {error(""+e);}

  }

  public static void main(String args[]) 
  {
    debug("Begin.");

    if (args.length < 2 )
    {
      System.out.println("Usage: java H4Replace <name data base file> <file name file> ");
      System.exit(0);
    }
    String ndb_name=args[0];
    String fnf_name=args[1];

    FilterDB ndb=new FilterDB(ndb_name);

    try
    {
      WordInputStream fnf=new WordInputStream(new FileInputStream(new File(fnf_name)));

      while (true)
      {
        String w1 = fnf.readWord();
        if (w1==null) break;

        String w2=w1+".bak";
        File f1 = new File(w1);
        File f2 = new File(w2);
        f1.renameTo(f2);

        new H4Replace(ndb,w2,w1);
      }
    }
    catch (IOException e) { error("file name file " + fnf_name + " " + e); }

    debug("end.");
  }
}