#define IMAGEIO_SOURCE_C_C
#include "imageio.h"

#if !defined(DELTA)
# define DELTA 1e-9
#endif

MAT_I ReadP5(char *fName, int *row, int *col)
{
  FILE *IN;
  MAT_I dArray;
  char string[256];
  int ftype;
  int i,j; 
  if ( (IN= fopen(fName,"rb"))==NULL)  {
    fprintf(stderr,"Cannot open file '%s'\n", fName);
    *row = *col = 0;
    return NULL;
  }
  fscanf(IN,"%s",string);
  if ( strcmp(string,"P5") && strcmp(string,"P2") ) {
    fprintf(stderr,"The system only works for P5 and P2 type PGM file.\n");
    fclose(IN);
    *row = *col = 0;
    return NULL;
  }
  ftype = 0;
  if (strcmp(string,"P2") == 0) {
    ftype = 1;
  }
  while (1) {
    fscanf(IN,"%s",string); 
    if (string[0] == '#') {
      while (  getc(IN) != '\n');
    }
    else {
      sscanf(string,"%d",col);
      break;
    }
  }
  fscanf(IN, "%d%d",row,&i);
  getc(IN);
  
  dArray = Create_Int_Matrix(*row, *col);
  if (ftype == 0) {
    for (i=0; i< (*row); i++) {
      for (j=0; j <(*col); j++) {
	dArray[i][j] = getc(IN);
      }
    }
  }
  else {
    for (i=0; i< (*row); i++) {
      for (j=0; j <(*col); j++) {
	fscanf(IN,"%d", &(dArray[i][j]));
      }
    }
  }

  fclose(IN);
  
  return dArray;
}




void WriteP5Char(char *fName, int scale, int row, int col, 
		 MAT_I dArray)
{
  FILE *OUT;
  int i,j;
  int c;
  if ( (OUT = fopen(fName, "wb")) == NULL) {
    fprintf(stderr,"Failed when writing file '%s'.\n", fName);
    return;
  }
  printf("Writing '%s' ..... ", fName);
  fflush(stdout);
  fprintf(OUT,"P5\n");
  fprintf(OUT,"%d %d\n%d\n",col,row,255);
  for (i=0; i<row; i++) {
    for (j=0; j< col; j++) {
      c = dArray[i][j] * scale;
      if (c > 255) c = 255;
      if (c < 0) c = 0;
      putc(c, OUT); 
    }
  }
  fclose(OUT);
  printf(" DONE.\n");
  return;
}

void ReadP6(char *fName, IMAGEINT_MBAND *image)
{
  FILE *IN;
  char string[256], fileTypeName[256];
  int ftype;
  int i,j,k;
  int row, col;
  int maxval;
  unsigned short int aword;
  unsigned char ch, *cp;
  if ( (IN= fopen(fName,"rb"))==NULL)  {
    fprintf(stderr,"Cannot open file '%s'\n", fName);
    return;
  }
  fscanf(IN,"%s",fileTypeName);
  if ( strcmp(fileTypeName,"P5") && strcmp(fileTypeName,"P2") &&
       strcmp(fileTypeName,"P6") && strcmp(fileTypeName,"P3") ) {
    fprintf(stderr,"The system only works for P2, P3, P5, and P6 ");
    fprintf(stderr,"type PGM file.\n");
    fclose(IN);
    return;
  }
 
  while (1) {
    fscanf(IN,"%s",string); 
    if (string[0] == '#') {
      while (  getc(IN) != '\n');
    }
    else {
      sscanf(string,"%d",&col);
      break;
    }
  }
  /* Note here there should be one maximum regardless of how many
     color component. However, some softwares assume there is one maximum
     per color component  */
  
  fscanf(IN, "%d%d",&row,&i);
  maxval = i;
  /*if (maxval < j) maxval = j;
    if (maxval < k) maxval = k;
  */
  /*
  printf("row = %d col = %d and max=%d\n", row, col, maxval);
  */
  getc(IN); /* Read the extra white space following maximum number */
  if (strcmp(fileTypeName,"P2")==0||strcmp(fileTypeName,"P5")==0) {
    Create_Image_MBAND(image, row, col, (int)1);
  }
  else {
    Create_Image_MBAND(image, row, col, (int)3);
  }
  for (i=0; i< image->nrow; i++) {
    for (j=0; j < image->ncol; j++) {
      for (k=0; k < image->nband; k++) {
	if (strcmp(fileTypeName,"P2")==0||strcmp(fileTypeName,"P3")==0) {
	  fscanf(IN,"%d", &(image->bands[k].data[i][j]));
	}
	else {
	  if (maxval < 256) {
	    image->bands[k].data[i][j] = getc(IN);
	  }
	  else {
	    cp = (char *)&aword;
	    cp[1] = getc(IN);
	    cp[0] = getc(IN);
	    
	    image->bands[k].data[i][j] = (int)((aword*255+128)/maxval);
	    /*
	      if (i==0 && j==0) {
	      printf("%o %x %o %o\n", aword, aword, cp[0], cp[1]);
	      }
	      */
	  }
	}
      }
    }
  }
  /*
    printf("Check pixels in file %s\n", fName);
  do {
    printf("Pixel (col, row): ");
    scanf("%d%d",&j, &i);
    if (i<0 || i>= image->nrow) break;
    if (j<0 || j>= image->ncol) break;
   
    printf("R = %d G=%d B=%d\n",image->bands[0].data[i][j],
	   image->bands[1].data[i][j],
	   image->bands[2].data[i][j]);
  } while(1);
  */
  fclose(IN);
  
  return;
}


void ReadP6COIL(char *fName, IMAGEINT_MBAND *image)
{
  FILE *IN;
  char string[32];
  int ftype;
  int i,j,k;
  int row, col;
  int maxval;
  unsigned short int aword;
  unsigned char ch, *cp;
  if ( (IN= fopen(fName,"rb"))==NULL)  {
    fprintf(stderr,"Cannot open file '%s'\n", fName);
    return;
  }
  fscanf(IN,"%s",string);
  if ( strcmp(string,"P5") && strcmp(string,"P2") &&
       strcmp(string,"P6") ) {
    fprintf(stderr,"The system only works for P2, P5, and P6 ");
    fprintf(stderr,"type PGM file.\n");
    fclose(IN);
    return;
  }
  if (strcmp(string,"P2")==0||strcmp(string,"P5")==0) {
    fprintf(stderr,"Please use ReadP5 to read P2 and P5 images.\n");
    fclose(IN);
    return;
  }
  
  while (1) {
    fscanf(IN,"%s",string); 
    if (string[0] == '#') {
      while (  getc(IN) != '\n');
    }
    else {
      sscanf(string,"%d",&col);
      break;
    }
  }
  /* Note here there is a maximum each color component and so there are
     three maximum numbers instead of one */
  
  fscanf(IN, "%d%d%d%d",&row,&i,&j,&k);
  maxval = i;
  if (maxval < j) maxval = j;
  if (maxval < k) maxval = k;
  
  printf(" row = %d col = %d and max=%d ", row, col, maxval);
  getc(IN);
  Create_Image_MBAND(image, row, col, (int)3);
  
  for (i=0; i< image->nrow; i++) {
    for (j=0; j < image->ncol; j++) {
      for (k=0; k < image->nband; k++) {
	if (maxval < 256) {
	  image->bands[k].data[i][j] = getc(IN);
	}
	else {
	  cp = (char *)&aword;
	  cp[1] = getc(IN);
	  cp[0] = getc(IN);
	  
	  image->bands[k].data[i][j] = (int)((aword*255+128)/maxval);
	  /*if (i==0 && j==0) {
	    printf("%o %x %o %o\n", aword, aword, cp[0], cp[1]);
	  }
	  */
	}
      }
    }
  }
  /*
  printf("Check pixels in file %s\n", fName);
  do {
    printf("Pixel (col, row): ");
    scanf("%d%d",&j, &i);
    if (i<0 || i>= image->nrow) break;
    if (j<0 || j>= image->ncol) break;
   
    printf("R = %d G=%d B=%d\n",image->bands[0].data[i][j],
	   image->bands[1].data[i][j],
	   image->bands[2].data[i][j]);
  } while(1);
  */
  fclose(IN);
  
  return;
}



void WriteP6Char(char *fName, IMAGEINT_MBAND *image, int scale)
{
  FILE *OUT;
  int i,j,k;
  int c;
  if ( (OUT = fopen(fName, "wb")) == NULL) {
    fprintf(stderr,"Failed when writing file '%s'.\n", fName);
    return;
  }
  printf("Writing '%s' ..... ", fName);
  fflush(stdout);
  if (image->nband == 1) {
    fprintf(OUT,"P5\n");
  }
  else {
    fprintf(OUT,"P6\n");
  }
  fprintf(OUT,"%d %d\n%d\n",image->ncol,image->nrow,255);
  for (i=0; i<image->nrow; i++) {
    for (j=0; j< image->ncol; j++) {
      for (k=0; k < image->nband; k++) {
	c = image->bands[k].data[i][j] * scale;
	if (c > 255) c = 255;
	if (c < 0) c = 0;
	putc(c, OUT);
      }
    }
  }
  fclose(OUT);
  printf(" DONE.\n");
  return;
}

void Free_Image_MBAND(IMAGEINT_MBAND *image)
{
  int k;
  if (image->nband > 0) {
    for (k=0; k < image->nband; k++) {
      Free_Image_Int(&(image->bands[k]));
    }
    free(image->bands);
  }
  image->nband = 0;
  return;
}


int Create_Image_MBAND(IMAGEINT_MBAND *image, int row, int col, int nband)
{
  int k;
  if (image->nband>0) {
    Free_Image_MBAND(image);
  }
  image->nband = nband; image->nrow = row; image->ncol = col;
  image->bands = (IMAGEINT *)malloc(sizeof(IMAGEINT) * image->nband);
  for (k=0; k < nband; k++) {
    image->bands[k].nrow = 0;
    Create_An_Image_Int(image->nrow, image->ncol, &(image->bands[k]));
  }
  return 0;
}


int Read_An_Image_Int(char *name, IMAGEINT *animage)
{
  if (animage->nrow >0 ) {
    Free_Image_Int(animage);
  }
  animage->data = ReadP5(name, &(animage->nrow), &(animage->ncol));
  if (animage->data == NULL) return -1;
  return 0;
}

int Write_An_Image_Int(IMAGEINT *animage, int scale, char *name)
{
  WriteP5Char(name, scale, animage->nrow, animage->ncol, animage->data);
  return;
}

int Create_An_Image_Int(int nrow, int ncol, IMAGEINT *animage)
{
  if (animage->nrow == nrow && animage->ncol == ncol) return 0;
  if (animage->nrow >0 ) {
    Free_Image_Int(animage);
  }
  animage->data = Create_Int_Matrix(nrow, ncol);
  animage->nrow = nrow;
  animage->ncol = ncol;
  return 0;
}

void Free_Image_Int(IMAGEINT *animage)
{
  if (animage->nrow >0 ) {
    Free_Int_Matrix(animage->data, animage->nrow);
    animage->nrow = 0;
  }
  return;
}


int Write_An_Image_Float(IMAGEFLOAT *animage, char *name)
{
  int i, j;
  float scale, min, max;
  IMAGEINT tmpImg;
  tmpImg.nrow = 0;
  min  = max = animage->data[0][0];
  Create_An_Image_Int(animage->nrow, animage->ncol, &tmpImg);
  for (i=0; i < animage->nrow; i++) {
    for (j=0; j<animage->ncol; j++) {
      if ( min >  animage->data[i][j])
	min = animage->data[i][j];
      if (max < animage->data[i][j])
	max = animage->data[i][j];
    }
  }
  if (max < (min+DELTA)) max = min+DELTA;
  scale = 255./(max-min);
  for (i=0; i < animage->nrow; i++) {
    for (j=0; j < animage->ncol; j++) {
      tmpImg.data[i][j] = (int)((animage->data[i][j]-min)*scale);
    }
  }
  WriteP5Char(name, (int)1, tmpImg.nrow, tmpImg.ncol, tmpImg.data);
  Free_Image_Int(&tmpImg);
  return;
}

int Create_An_Image_Float(int nrow, int ncol, IMAGEFLOAT *animage)
{
  if (animage->nrow == nrow && animage->ncol == ncol) return 0;
  if (animage->nrow >0 ) {
    Free_Image_Float(animage);
  }
  animage->data = Create_Matrix(nrow, ncol);
  animage->nrow = nrow;
  animage->ncol = ncol;
  return 0;
}


int Init_An_Image_Float(IMAGEFLOAT *animage, float cVal)
{
  int i,j;
  for (i=0; i < animage->nrow; i++) {
    for (j=0; j < animage->ncol; j++) {
      animage->data[i][j] = cVal;
    }
  }
  return 0;
}


void Free_Image_Float(IMAGEFLOAT *animage)
{
  if (animage->nrow >0 ) {
    Free_Matrix(animage->data, animage->nrow);
    animage->nrow = 0;
  }
  return;
}