/**
  * Converts HF broadcast station data file HF_BCD.txt to required data files
  * @author Robert J Morton
  * @version 22 November 2001 */

// This program uses the Java 1.1.8 API.

import java.io.*;

class hfbdp {
  public static void main(String args[]) throws IOException {

    BufferedReader
      r = new BufferedReader(
            new InputStreamReader(
              new FileInputStream("hfbsn.txt")
            )
          );

    Writer
      stations = new FileWriter("stations.txt"),
      // create frequencies file for first station
      frequencies = new FileWriter("freqs000.txt"),
      // create duplicates file
      dups = new FileWriter("duplicates.txt");

    String
      old_frequency = "",  // for capturing duplicates
      old_station = "",    // for capturing duplicates
      STATION = "",        // name of station currently being dealt with
      s;                   // to hold the current input line

    int sn = 0;            // number of station within the list


    /* While there are more lines of text to be read in, read in the next
    line of text, find the position ofthe 'tab' character that separates
    the frequency from from the station name, get the new station name and
    strip from it any possible rogue spaces. */

    while((s = r.readLine()) != null) {
      int x = s.indexOf('\t');
      String frequency = (s.substring(0, x));
      String station = (s.substring(x + 1, s.length())).trim();

      // If this is a duplicate entry, write it to duplicates file.
      if(frequency.equals(old_frequency) && station.equals(old_station))
        dups.write(frequency + '\t' + station + "\n");

      old_frequency = frequency;
      old_station = station;

      /* If we are still dealing with the same stationand
      write the next frequency for this station. */

      if(STATION.compareTo(station) == 0) {
        frequencies.write(frequency + "\n");

      /* Otherwise, it is a new station, so make this station's name the
      current station name and write its name to stations file. */

      } else {
        STATION = station;
        stations.write(station + "\n");

        /* Provided the previous station actually had at
        least one frequency, close its frequencies file*/

        if(sn > 0) frequencies.close();

        String SN = "" + sn;  // form string version of station number
        if(sn < 10)           // if it is less than 10
          SN = "00" + SN;     // pad it out with 2 leading zeros
        else if(sn < 100)     // else if it is less than 100
          SN = "0" + SN;      // pad it with just 1 leading zero

        /* Create a new frequencies file for this station
        and write first frequency for this station. */

        frequencies = new FileWriter("freqs" + SN + ".txt");
        frequencies.write(frequency + "\n");

        sn++;  // increment station number for next time
      }
    }    // end of while loop

    dups.close();
    stations.close();
    frequencies.close();
    r.close();
  }
}