# include <math.h>
# include <stdio.h>
# include <stdlib.h>

# include "ppc_array.h"
# include "ppc_image.h"
# include "ppc_netpbm_io.h"
# include "ppc_xmalloc.h"

/******************************************************************************/

void free_image ( struct image *img )

/******************************************************************************/
/*
  Purpose:

    free_image() frees memory associated with a netpbm image.

  Licensing:

    This code is distributed under the MIT license. 

  Modified:

    14 September 2023

  Author:

    Original C version by Rouben Rostamian.
    This version by John Burkardt.

  Reference:

    Rouben Rostamian,
    Programming Projects in C 
    for Students of Engineering, Science, and Mathematics,
    SIAM, 2014,
    ISBN: 978-1-611973-49-5

  Input:

    struct image *img: the image information.
*/
{
  if ( img != NULL )
  {
    free_matrix ( img->r );
    free_matrix ( img->g );
    free_matrix ( img->b );
    free ( img );
  }
  return;
}
/******************************************************************************/

struct image *read_image ( char *filename )

/******************************************************************************/
/*
  Purpose:

    read_image() reads an image from a netpbm() file.

  Licensing:

    This code is distributed under the MIT license. 

  Modified:

    14 September 2023

  Author:

    Original C version by Rouben Rostamian.
    This version by John Burkardt.

  Reference:

    Rouben Rostamian,
    Programming Projects in C 
    for Students of Engineering, Science, and Mathematics,
    SIAM, 2014,
    ISBN: 978-1-611973-49-5

  Input:

    char *filename: the name of the file containing image information.

  Output:

    struct image *img: the image information.
*/
{
  struct image *img = xmalloc ( sizeof *img );
  struct pam *pam = &img -> pam;
  FILE *fp = pm_openr ( filename );

  pnm_readpaminit ( fp, pam, sizeof ( struct pam ) );
/*
  pnm_readpaminit ( fp, pam, PAM_STRUCT_SIZE ( tuple_type ) );
*/
  if ( pam->format == PGM_FORMAT ||
       pam->format == RPGM_FORMAT )
  {
    read_pgm_pixel_data ( img );
  }
  else if ( pam->format == PPM_FORMAT ||
            pam->format == RPPM_FORMAT )
  {
    read_ppm_pixel_data ( img );
  }
  else
  {
    fprintf ( stderr, "\n" );
    fprintf ( stderr, "read_image(): Fatal error!\n" );
    fprintf ( stderr, "  Input file is not PGM or PPM format.\n" );
    exit ( EXIT_FAILURE );
  }

  pm_close ( fp );

  return img;
}
/******************************************************************************/

void read_pgm_pixel_data ( struct image *img )

/******************************************************************************/
/*
  Purpose:

    read_pgm_pixel_data() reads the information from a PGM image.

  Licensing:

    This code is distributed under the MIT license. 

  Modified:

    15 September 2023

  Author:

    Original C version by Rouben Rostamian.
    This version by John Burkardt.

  Reference:

    Rouben Rostamian,
    Programming Projects in C 
    for Students of Engineering, Science, and Mathematics,
    SIAM, 2014,
    ISBN: 978-1-611973-49-5

  Input:

    struct image *img: the image information.

  Output:

    struct image *img: the image information, with the pixel information in g.
*/
{
  int i;
  int j;

  struct pam *pam = &img -> pam;
  tuple *row = pnm_allocpamrow ( pam );

  make_matrix ( img->g, pam->height, pam->width );

  img->r = NULL;
  img->b = NULL;

  for ( i = 0; i < pam->height; i++ )
  {
    pnm_readpamrow ( pam, row );
    for ( j = 0; j < pam->width; j++ )
    {
      img->g[i][j] = row[j][0];
    }
  }
  pnm_freepamrow ( row );

  return;
}
/******************************************************************************/

void read_ppm_pixel_data ( struct image *img )

/******************************************************************************/
/*
  Purpose:

    read_ppm_pixel_data() reads the information from a PPM image.

  Licensing:

    This code is distributed under the MIT license. 

  Modified:

    15 September 2023

  Author:

    Original C version by Rouben Rostamian.
    This version by John Burkardt.

  Reference:

    Rouben Rostamian,
    Programming Projects in C 
    for Students of Engineering, Science, and Mathematics,
    SIAM, 2014,
    ISBN: 978-1-611973-49-5

  Input:

    struct image *img: the image information.

  Output:

    struct image *img: the image information, with the pixel information 
    in r, g, b.
*/
{
  int i;
  int j;

  struct pam *pam = &img -> pam;
  tuple *row = pnm_allocpamrow ( pam );

  make_matrix ( img->r, pam->height, pam->width );
  make_matrix ( img->g, pam->height, pam->width );
  make_matrix ( img->b, pam->height, pam->width );

  for ( i = 0; i < pam->height; i++ )
  {
    pnm_readpamrow ( pam, row );
    for ( j = 0; j < pam->width; j++ )
    {
      img->r[i][j] = row[j][0];
      img->g[i][j] = row[j][1];
      img->b[i][j] = row[j][2];
    }
  }
  pnm_freepamrow ( row );

  return;
}
/******************************************************************************/

void write_image ( char *filename, struct image *img )

/******************************************************************************/
/*
  Purpose:

    write_image() writes netpbm image information to a file.

  Licensing:

    This code is distributed under the MIT license. 

  Modified:

    14 September 2023

  Author:

    Original C version by Rouben Rostamian.
    This version by John Burkardt.

  Reference:

    Rouben Rostamian,
    Programming Projects in C 
    for Students of Engineering, Science, and Mathematics,
    SIAM, 2014,
    ISBN: 978-1-611973-49-5

  Input:

    char *filename: the name of the file containing image information.

    struct image *img: the image information.
*/
{
  struct pam *pam = &img->pam;
  pam->file = pm_openw ( filename );

  if ( pam->format == PGM_FORMAT || pam->format == PPM_FORMAT )
  {
    pam->plainformat = 1;
  }
  else
  {
    pam->plainformat = 0;
  }
  pnm_writepaminit ( pam );

  if ( pam->format == PGM_FORMAT || pam->format == RPGM_FORMAT )
  {
    write_pgm_pixel_data ( img );
  }
  else if ( pam->format == PPM_FORMAT || pam->format == RPPM_FORMAT )
  {
    write_ppm_pixel_data ( img );
  }
  else
  {
    fprintf ( stderr, "\n" );
    fprintf ( stderr, "write_image(): Fatal error!\n" );
    fprintf ( stderr, "  Input file is not PGM or PPM format.\n" );
    exit ( EXIT_FAILURE );
  }

  pm_close ( pam->file );

  return;
}
/******************************************************************************/

void write_pgm_pixel_data ( struct image *img )

/******************************************************************************/
/*
  Purpose:

    write_pgm_pixel_data() writes netpbm image information to a PGM file.

  Licensing:

    This code is distributed under the MIT license. 

  Modified:

    15 September 2023

  Author:

    Original C version by Rouben Rostamian.
    This version by John Burkardt.

  Reference:

    Rouben Rostamian,
    Programming Projects in C 
    for Students of Engineering, Science, and Mathematics,
    SIAM, 2014,
    ISBN: 978-1-611973-49-5

  Input:

    struct image *img: the image information.
*/
{
  int i;
  int j;

  struct pam *pam = &img->pam;
  tuple *row = pnm_allocpamrow ( pam );

  for ( i = 0; i < pam->height; i++ )
  {
    for ( j = 0; j < pam->width; j++ )
    {
      row[j][0] = img->g[i][j];
    }
    pnm_writepamrow ( pam, row );
  }
  pnm_freepamrow ( row );

  return;
}
/******************************************************************************/

void write_ppm_pixel_data ( struct image *img )

/******************************************************************************/
/*
  Purpose:

    write_ppm_pixel_data() writes netpbm image information to a PPM file.

  Licensing:

    This code is distributed under the MIT license. 

  Modified:

    15 September 2023

  Author:

    Original C version by Rouben Rostamian.
    This version by John Burkardt.

  Reference:

    Rouben Rostamian,
    Programming Projects in C 
    for Students of Engineering, Science, and Mathematics,
    SIAM, 2014,
    ISBN: 978-1-611973-49-5

  Input:

    struct image *img: the image information.
*/
{
  int i;
  int j;

  struct pam *pam = &img->pam;
  tuple *row = pnm_allocpamrow ( pam );

  for ( i = 0; i < pam->height; i++ )
  {
    for ( j = 0; j < pam->width; j++ )
    {
      row[j][0] = img->r[i][j];
      row[j][1] = img->g[i][j];
      row[j][2] = img->b[i][j];
    }
    pnm_writepamrow ( pam, row );
  }
  pnm_freepamrow ( row );

  return;
}