/*
 * (C) 2004 - Geotechnical Software Services
 * 
 * This code is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public 
 * License as published by the Free Software Foundation; either 
 * version 2.1 of the License, or (at your option) any later version.
 *
 * This code is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 * GNU Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public 
 * License along with this program; if not, write to the Free 
 * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, 
 * MA  02111-1307, USA.
 */
package no.geosoft.cc.util;



/**
 * Utility class for doing byte swapping (i.e. conversion between
 * little-endian and big-endian representations) of different data types.
 * Byte swapping is typically used when data is read from a stream 
 * delivered by a system of different endian type as the present one.
 * 
 * @author <a href="mailto:info@geosoft.no">GeoSoft</a>
 */   
public class ByteSwapper
{
  /**
   * Byte swap a single short value.
   * 
   * @param value  Value to byte swap.
   * @return       Byte swapped representation.
   */
  public static short swap (short value)
  {
    int b1 = value & 0xff;
    int b2 = (value >> 8) & 0xff;

    return (short) (b1 << 8 | b2 << 0);
  }

  

  /**
   * Byte swap a single int value.
   * 
   * @param value  Value to byte swap.
   * @return       Byte swapped representation.
   */
  public static int swap (int value)
  {
    int b1 = (value >>  0) & 0xff;
    int b2 = (value >>  8) & 0xff;
    int b3 = (value >> 16) & 0xff;
    int b4 = (value >> 24) & 0xff;

    return b1 << 24 | b2 << 16 | b3 << 8 | b4 << 0;
  }

  

  /**
   * Byte swap a single long value.
   * 
   * @param value  Value to byte swap.
   * @return       Byte swapped representation.
   */
  public static long swap (long value)
  {
    long b1 = (value >>  0) & 0xff;
    long b2 = (value >>  8) & 0xff;
    long b3 = (value >> 16) & 0xff;
    long b4 = (value >> 24) & 0xff;
    long b5 = (value >> 32) & 0xff;
    long b6 = (value >> 40) & 0xff;
    long b7 = (value >> 48) & 0xff;
    long b8 = (value >> 56) & 0xff;

    return b1 << 56 | b2 << 48 | b3 << 40 | b4 << 32 |
           b5 << 24 | b6 << 16 | b7 <<  8 | b8 <<  0;
  }
  

  
  /**
   * Byte swap a single float value.
   * 
   * @param value  Value to byte swap.
   * @return       Byte swapped representation.
   */
  public static float swap (float value)
  {
    int intValue = Float.floatToIntBits (value);
    intValue = swap (intValue);
    return Float.intBitsToFloat (intValue);
  }

  

  /**
   * Byte swap a single double value.
   * 
   * @param value  Value to byte swap.
   * @return       Byte swapped representation.
   */
  public static double swap (double value)
  {
    long longValue = Double.doubleToLongBits (value);
    longValue = swap (longValue);
    return Double.longBitsToDouble (longValue);
  }


  
  /**
   * Byte swap an array of shorts. The result of the swapping
   * is put back into the specified array.
   *
   * @param array  Array of values to swap
   */
  public static void swap (short[] array)
  {
    for (int i = 0; i < array.length; i++)
      array[i] = swap (array[i]);
  }

  
  
  /**
   * Byte swap an array of ints. The result of the swapping
   * is put back into the specified array.
   * 
   * @param array  Array of values to swap
   */
  public static void swap (int[] array)
  {
    for (int i = 0; i < array.length; i++)
      array[i] = swap (array[i]);
  }


  
  /**
   * Byte swap an array of longs. The result of the swapping
   * is put back into the specified array.
   * 
   * @param array  Array of values to swap
   */
  public static void swap (long[] array)
  {
    for (int i = 0; i < array.length; i++)
      array[i] = swap (array[i]);
  }


  
  /**
   * Byte swap an array of floats. The result of the swapping
   * is put back into the specified array.
   * 
   * @param array  Array of values to swap
   */
  public static void swap (float[] array)
  {
    for (int i = 0; i < array.length; i++)
      array[i] = swap (array[i]);
  }


  
  /**
   * Byte swap an array of doubles. The result of the swapping
   * is put back into the specified array.
   * 
   * @param array  Array of values to swap
   */
  public static void swap (double[] array)
  {
    for (int i = 0; i < array.length; i++)
      array[i] = swap (array[i]);
  }
}