/*
  This file was downloaded from the CFITSIO utilities web page:
    http://heasarc.gsfc.nasa.gov/docs/software/fitsio/cexamples.html

  That page contains this text:
    You may freely modify, reuse, and redistribute these programs as you wish.

  We assume it was originally written by the CFITSIO authors (primarily William
  D. Pence).
*/
/*
  This file is part of the Astrometry.net suite.
  Copyright 2007 Dustin Lang, Keir Mierle and Sam Roweis.

  The Astrometry.net suite is free software; you can redistribute
  it and/or modify it under the terms of the GNU General Public License
  as published by the Free Software Foundation, version 2.

  The Astrometry.net suite 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
  General Public License for more details.

  You should have received a copy of the GNU General Public License
  along with the Astrometry.net suite ; if not, write to the Free Software
  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301 USA
*/

#include <string.h>
#include <stdio.h>
#include <stdlib.h>
#include "fitsio.h"

int main(int argc, char *argv[])
{
    fitsfile *infptr, *outfptr;   /* FITS file pointers defined in fitsio.h */
    int status = 0, ii = 1, iteration = 0, single = 0, hdupos;
    int hdutype, bitpix, bytepix, naxis = 0, nkeys, datatype = 0, anynul;
    long naxes[9] = {1, 1, 1, 1, 1, 1, 1, 1, 1};
    long first, totpix = 0, npix;
    double *array, bscale = 1.0, bzero = 0.0, nulval = 0.;
    char card[81];

    if (argc != 3)
    {
 printf("\n");
 printf("Usage:  imcopy inputImage outputImage[compress]\n");
 printf("\n");
 printf("Copy an input image to an output image, optionally compressing\n");
 printf("or uncompressing the image in the process.  If the [compress]\n");
 printf("qualifier is appended to the output file name then the input image\n");
 printf("will be compressed using the tile-compressed format.  In this format,\n");
 printf("the image is divided into rectangular tiles and each tile of pixels\n");
 printf("is compressed and stored in a variable-length row of a binary table.\n");
 printf("If the [compress] qualifier is omitted, and the input image is\n");
 printf("in tile-compressed format, then the output image will be uncompressed.\n");
 printf("\n");
 printf("If an extension name or number is appended to the input file name, \n");
 printf("enclosed in square brackets, then only that single extension will be\n");
 printf("copied to the output file.  Otherwise, every extension in the input file\n");
 printf("will be processed in turn and copied to the output file.\n");
 printf("\n");
 printf("Examples:\n");
 printf("\n");
 printf("1)  imcopy image.fit 'cimage.fit[compress]'\n");
 printf("\n");
 printf("    This compresses the input image using the default parameters, i.e.,\n");
 printf("    using the Rice compression algorithm and using row by row tiles.\n");
 printf("\n");
 printf("2)  imcopy cimage.fit image2.fit\n");
 printf("\n");
 printf("    This uncompress the image created in the first example.\n");
 printf("    image2.fit should be identical to image.fit if the image\n");
 printf("    has an integer datatype.  There will be small differences\n");
 printf("    in the pixel values if it is a floating point image.\n");
 printf("\n");
 printf("3)  imcopy image.fit 'cimage.fit[compress GZIP 100,100;4]'\n");
 printf("\n");
 printf("    This compresses the input image using the following parameters:\n");
 printf("         GZIP compression algorithm;\n");
 printf("         100 X 100 pixel compression tiles;\n");
 printf("         noise_bits = 4 (only used with floating point images)\n");
 printf("\n");
 printf("The full syntax of the compression qualifier is:\n");
 printf("    [compress ALGORITHM TDIM1,TDIM2,...; NOISE_BITS]\n");
 printf("where the allowed ALGORITHM values are Rice, GZIP, PLIO, \n");
 printf("and TDIMn is the size of the compression tile in each dimension,\n");
 printf("and NOISE_BITS = 1, 2, 3, or 4 and controls the amount of noise\n");
 printf("suppression when compressing floating point images. \n");
 printf("\n");
 printf("Note that it may be necessary to enclose the file names\n");
 printf("in single quote characters on the Unix command line.\n");
      return(0);
    }

    /* Open the input file and create output file */
    fits_open_file(&infptr, argv[1], READONLY, &status);
    fits_create_file(&outfptr, argv[2], &status);

    if (status != 0) {    
        fits_report_error(stderr, status);
        return(status);
    }

    fits_get_hdu_num(infptr, &hdupos);  /* Get the current HDU position */

    /* Copy only a single HDU if a specific extension was given */ 
    if (hdupos != 1 || strchr(argv[1], '[')) single = 1;

    for (; !status; hdupos++)  /* Main loop through each extension */
    {

      fits_get_hdu_type(infptr, &hdutype, &status);

      if (hdutype == IMAGE_HDU) {

          /* get image dimensions and total number of pixels in image */
          for (ii = 0; ii < 9; ii++)
              naxes[ii] = 1;

          fits_get_img_param(infptr, 9, &bitpix, &naxis, naxes, &status);

          totpix = naxes[0] * naxes[1] * naxes[2] * naxes[3] * naxes[4]
             * naxes[5] * naxes[6] * naxes[7] * naxes[8];
      }

      if (hdutype != IMAGE_HDU || naxis == 0 || totpix == 0) { 

          /* just copy tables and null images */
          fits_copy_hdu(infptr, outfptr, 0, &status);

      } else {

          /* Explicitly create new image, to support compression */
          fits_create_img(outfptr, bitpix, naxis, naxes, &status);

          /* copy all the user keywords (not the structural keywords) */
          fits_get_hdrspace(infptr, &nkeys, NULL, &status); 

          for (ii = 1; ii <= nkeys; ii++) {
              fits_read_record(infptr, ii, card, &status);
              if (fits_get_keyclass(card) > TYP_CMPRS_KEY)
                  fits_write_record(outfptr, card, &status);
          }

          switch(bitpix) {
              case BYTE_IMG:
                  datatype = TBYTE;
                  break;
              case SHORT_IMG:
                  datatype = TSHORT;
                  break;
              case LONG_IMG:
                  datatype = TLONG;
                  break;
              case FLOAT_IMG:
                  datatype = TFLOAT;
                  break;
              case DOUBLE_IMG:
                  datatype = TDOUBLE;
                  break;
          }

          bytepix = abs(bitpix) / 8;

          npix = totpix;
          iteration = 0;

          /* try to allocate memory for the entire image */
          /* use double type to force memory alignment */
          array = (double *) calloc(npix, bytepix);

          /* if allocation failed, divide size by 2 and try again */
          while (!array && iteration < 10)  {
              iteration++;
              npix = npix / 2;
              array = (double *) calloc(npix, bytepix);
          }

          if (!array)  {
              printf("Memory allocation error\n");
              return(0);
          }

          /* turn off any scaling so that we copy the raw pixel values */
          fits_set_bscale(infptr,  bscale, bzero, &status);
          fits_set_bscale(outfptr, bscale, bzero, &status);

          first = 1;
          while (totpix > 0 && !status)
          {
             /* read all or part of image then write it back to the output file */
             fits_read_img(infptr, datatype, first, npix, 
                     &nulval, array, &anynul, &status);

             fits_write_img(outfptr, datatype, first, npix, array, &status);
             totpix = totpix - npix;
             first  = first  + npix;
          }
          free(array);
      }

      if (single) break;  /* quit if only copying a single HDU */
      fits_movrel_hdu(infptr, 1, NULL, &status);  /* try to move to next HDU */
    }

    if (status == END_OF_FILE)  status = 0; /* Reset after normal error */

    fits_close_file(outfptr,  &status);
    fits_close_file(infptr, &status);

    /* if error occurred, print out error message */
    if (status)
       fits_report_error(stderr, status);
    return(status);
}
