// Updates: 2006.02.14


import java.io.*;


/**
 * Converts the WGS84 coordinates of a track file (track.txt) provided by the
 * GeoVTag application in CH1903. 
 *  
 * @author Michel Deriaz
 */
public class Track2CH1903 {

  /** 
   * An abreviation equals to Double.NEGATIVE_INFINITY, used as an error code.
   */
  public static final double NI = Double.NEGATIVE_INFINITY;

  
  /**
   * Main method. Lines with errors are ignored.
   */
  public static void main(String[] args) {
    String result = "";
    String data = readFile("track.txt");
    String[] lines = data.split("\\r\\n|\\r|\\n");
    for (int i = 0; i < lines.length; i++) {
      String[] items = lines[i].split(",");
      if (items.length < 2) continue; // ignore lines with errors
      double latSec = NI;
      double lonSec = NI;
      try {
        latSec = Double.parseDouble(items[1]) * 3600;
        lonSec = Double.parseDouble(items[2]) * 3600;
      }
      catch (Exception e) {
        continue; // ignore lines with errors
      }
      double[] inCH = WGS84ToCH1903(latSec, lonSec);
      result += items[0] + "," + inCH[0] + "," + inCH[1];
//      for (int j = 3; j < items.length; j++) {
//        result += "," + items[j];
//      }
      result += "\n";
    }
    writeFile("track.txt", result);
  }
  
  
  /**
   * Transforms WGS84 coordinates in CH1903.
   * @param latSec the latitude, in seconds
   * @param lonSec the longitude, in seconds
   * @return a (x,y) couple of CH coordinates
   */
  public static double[] WGS84ToCH1903(double latSec, double lonSec) {
    double[] result = new double[2];
    double lat2 = (latSec - 169028.66) / 10000;
    double lon2 = (lonSec - 26782.5) / 10000;
    result[0] = 200147.07
                + 308807.95 * lat2
                + 3745.25 * lon2 * lon2
                + 76.63 * lat2 * lat2
                - 194.56 * lon2 * lon2 * lat2
                + 119.79 * lat2 * lat2 * lat2;
    result[1] = 600072.37
                + 211455.93 * lon2
                - 10938.51 * lon2 * lat2
                - 0.36 * lon2 * lat2 * lat2
                - 44.54 * lon2 * lon2 * lon2;    
    return result;
  }
   
    
  private static String readFile(String name) {
    File f = new File(name);
    int size = (int)f.length ();
    char[] cbuf = new char[size];
    try {
      FileReader fr = new FileReader(name);    
      fr.read(cbuf);
      fr.close();
    }
    catch(IOException ioe) {
      return null;
    }
    return String.valueOf(cbuf);
  }


  private static void writeFile(String name, String text) {
    try {
      FileWriter fw = new FileWriter(name);
      fw.write(text);
      fw.close();
    }
    catch(IOException ioe) {
      System.out.println(ioe);
    }
  }           
}