#include <port.h>

#include <stdio.h>
#include <string.h>
#include "imgformat.h"
#include "memory.h"

PGMImage *read_pgm_file(char *fn)
  {
  FILE		*ifp ;
  PGMImage	*pgmimage ;
  char		stringbuf[255], strbuf2[255] ;
  int		w, h, i, j ;
  
  ifp = fopen(fn, "rb") ;
  if (!ifp) errmsg("Input file not found") ;
  
  fscanf(ifp, "%s\n", stringbuf) ;
  if (strcmp(stringbuf, PGM_RAW) != 0)
    {
    fprintf(stderr, "Input file is not a PGM raw image.\n") ;
    return NULL ;
    }
  
  fgets(stringbuf, 255, ifp) ;	/* might be width and height */
  /* skip the comment line */
  while (stringbuf[0] == '#') fgets(stringbuf, 255, ifp) ;	
  sscanf(stringbuf, "%d %d", &w, &h) ;
  
  fgets(stringbuf, 255, ifp) ;	/* maximum gray value */
  sscanf(stringbuf, "%d", &i) ;
  pgmimage = (PGMImage *) malloc(sizeof(PGMImage)) ;
  strcpy(pgmimage->MagicValue, PGM_RAW) ;
  pgmimage->ImageWidth = w ;
  pgmimage->ImageHeight = h ;
  pgmimage->MaxGray = i ;
  pgmimage->data = ucmatrix(h, w) ;
  for (i = 0 ; i < h ; i++)
    for (j = 0 ; j < w ; j++)
      pgmimage->data[i][j] = (unsigned char) fgetc(ifp) ;
  fclose(ifp) ;
  return pgmimage ;
  }


int write_pgm_file(char *fn, PGMImage *pgmimage)
  {
  FILE		*ofp ;
  int		i, j ;
  
  ofp = fopen(fn, "wb") ;
  if (!ofp) errmsg("Output file open failed") ;
  
  fprintf(ofp, "%s\n", pgmimage->MagicValue) ;
  fprintf(ofp, "# %s\n", fn) ;
  fprintf(ofp, "%d %d\n", pgmimage->ImageWidth, pgmimage->ImageHeight) ;
  fprintf(ofp, "%d\n", pgmimage->MaxGray) ;
  for (i = 0 ; i < pgmimage->ImageHeight ; i++)
    for (j = 0 ; j < pgmimage->ImageWidth ; j++)
      fputc(pgmimage->data[i][j], ofp) ;
  fclose(ofp) ;
  return 1 ;
  }


void free_pgm_data(PGMImage *pgmimage)
  {
  free_ucmatrix(pgmimage->data, pgmimage->ImageHeight, pgmimage->ImageWidth) ;
  free(pgmimage) ; 
  }


PPMImage *read_ppm_file(char *fn)
  {
  FILE		*ifp ;
  PPMImage	*ppmimage ;
  char		stringbuf[255], strbuf2[255] ;
  int		w, h, i, j ;
  
  ifp = fopen(fn, "rb") ;
  if (!ifp) errmsg("Input file not found") ;
  
  fscanf(ifp, "%s\n", stringbuf) ;
  if (strcmp(stringbuf, PPM_RAW) != 0)
    {
    fprintf(stderr, "Input file is not a PPM raw image.\n") ;
    return NULL ;
    }
  
  fgets(stringbuf, 255, ifp) ;	/* might be width and height */
  /* skip the comment line */
  while (stringbuf[0] == '#') fgets(stringbuf, 255, ifp) ;	
  sscanf(stringbuf, "%d %d", &w, &h) ;
  
  fgets(stringbuf, 255, ifp) ;	/* max value per pixel */
  sscanf(stringbuf, "%d", &i) ;
  ppmimage = (PPMImage *) malloc(sizeof(PPMImage)) ;
  strcpy(ppmimage->MagicValue, PPM_RAW) ;
  ppmimage->ImageWidth = w ;
  ppmimage->ImageHeight = h ;
  ppmimage->MaxColor = i ;
  ppmimage->red = ucmatrix(h, w) ;	/* allocate memory for red band data */
  ppmimage->green = ucmatrix(h, w) ;	/* allocate memory for green band data */
  ppmimage->blue = ucmatrix(h, w) ;	/* allocate memory for blue band data */
  for (i = 0 ; i < h ; i++)
    for (j = 0 ; j < w ; j++)
      {
      ppmimage->red[i][j] = (unsigned char) fgetc(ifp) ;
      ppmimage->green[i][j] = (unsigned char) fgetc(ifp) ;
      ppmimage->blue[i][j] = (unsigned char) fgetc(ifp) ;
      }
  fclose(ifp) ;
  return ppmimage ;
  }


int write_ppm_file(char *fn, PPMImage *ppmimage)
  {
  FILE		*ofp ;
  int		i, j ;
  
  ofp = fopen(fn, "wb") ;
  if (!ofp) errmsg("Output file open failed") ;
  
  fprintf(ofp, "%s\n", ppmimage->MagicValue) ;
  fprintf(ofp, "# %s\n", fn) ;
  fprintf(ofp, "%d %d\n", ppmimage->ImageWidth, ppmimage->ImageHeight) ;
  fprintf(ofp, "%d\n", ppmimage->MaxColor) ;
  for (i = 0 ; i < ppmimage->ImageHeight ; i++)
    for (j = 0 ; j < ppmimage->ImageWidth ; j++)
      {
      fputc(ppmimage->red[i][j], ofp) ;
      fputc(ppmimage->green[i][j], ofp) ;
      fputc(ppmimage->blue[i][j], ofp) ;
      }
  fclose(ofp) ;
  return 1 ;
  }


void free_ppm_data(PPMImage *ppmimage)
  {
  free_ucmatrix(ppmimage->red, ppmimage->ImageHeight, ppmimage->ImageWidth) ;
  free_ucmatrix(ppmimage->green, ppmimage->ImageHeight, ppmimage->ImageWidth) ;
  free_ucmatrix(ppmimage->blue, ppmimage->ImageHeight, ppmimage->ImageWidth) ;
  free(ppmimage) ; 
  }