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

#include <jpeglib.h>
#include <argtable2.h>
#include <string.h>

const char * input_file;
const char * output_file;
const char * filter;

double times;
double percent;
double contrast_value;
double sepia;

/* we will be using this uninitialized pointer later to store raw, uncompressd image */
JSAMPARRAY row_pointers = NULL;


/* dimensions of the image we want to write */
JDIMENSION width;
JDIMENSION height;
int num_components;
int quality = 75;
J_COLOR_SPACE color_space;

void negate(){
  int x, y;
  if (color_space != JCS_RGB)  return;

  for (y=0; y<height; y++) {
    JSAMPROW row = row_pointers[y];
    for (x=0; x<width; x++) {
      JSAMPROW ptr = &(row[x*3]);
      

      ptr[0] = 255-ptr[0];
      ptr[1] = 255-ptr[1];
	  ptr[2] = 255-ptr[2];
    }
  }
}    

void brightness(int percent){
  int x, y;
 
  if (color_space != JCS_RGB) return;
 
  for (y = 0; y < height; y++) {
    JSAMPROW row = row_pointers[y];
 
    for (x = 0; x < width; x++) {
      JSAMPROW ptr = &(row[x * 3]);
 
      for (int c = 0; c < 3; c++) {
        int val = ptr[c] + (percent * ptr[c]) / 100;
 
        if (val > 255) val = 255;
        if (val < 0) val = 0;
 
        ptr[c] = (JSAMPLE) val;
      }
    }
  }
}


void contrast(double t)
{
    int x, y;

    if (color_space != JCS_RGB) return;

    for (y = 0; y < height; y++) {

        JSAMPROW row = row_pointers[y];

        for (x = 0; x < width; x++) {

            JSAMPROW ptr = &(row[x * 3]);

            for (int c = 0; c < 3; c++) {

                int val = t * (ptr[c] - 127) + 127;

                if (val > 255) val = 255;
                if (val < 0) val = 0;

                ptr[c] = (JSAMPLE) val;
            }
        }
    }
}  

void turnSepia(){
  int x, y;
 
  if (color_space != JCS_RGB) return;
 
  for (y = 0; y < height; y++) {
    JSAMPROW row = row_pointers[y];
 
    for (x = 0; x < width; x++) {
      JSAMPROW ptr = &(row[x * 3]);
 
      int r = ptr[0];
      int g = ptr[1];
      int b = ptr[2];
 
      int new_r = (int)(0.393 * r + 0.769 * g + 0.189 * b);
      int new_g = (int)(0.349 * r + 0.686 * g + 0.168 * b);
      int new_b = (int)(0.272 * r + 0.534 * g + 0.131 * b);
 
   
      if (new_r > 255) new_r = 255;
      if (new_g > 255) new_g = 255;
      if (new_b > 255) new_b = 255;
 
      ptr[0] = (JSAMPLE)new_r;
      ptr[1] = (JSAMPLE)new_g;
      ptr[2] = (JSAMPLE)new_b;
    }
  }
}
 


void process_file()
{
    if(strcmp(filter, "negate") == 0) {

        negate();
    }
    else if(strcmp(filter, "brightness") == 0) {

        brightness(percent);
        printf("wybrano filtr brightness\n");
    }
    else if(strcmp(filter, "contrast") == 0) {

        contrast(contrast_value);
        printf("wybrano filtr contrast\n");
    }
    else if(strcmp(filter, "sepia") == 0) {

        turnSepia();
        printf("wybrano filtr sepia\n");
    }
}




void abort_(const char * s, ...)
{
	va_list args;
	va_start(args, s);
	vfprintf(stderr, s, args);
	fprintf(stderr, "\n");
	va_end(args);
	abort();
}


/**
 * read_jpeg_file Reads from a jpeg file on disk specified by filename and saves into the 
 * raw_image buffer in an uncompressed format.
 * 
 * \returns positive integer if successful, -1 otherwise
 * \param *filename char string specifying the file name to read from
 *
 */

void read_jpeg_file( const char *filename )
{
	/* these are standard libjpeg structures for reading(decompression) */
	struct jpeg_decompress_struct cinfo;
	struct jpeg_error_mgr jerr;
	/* libjpeg data structure for storing one row, that is, scanline of an image */
	int y;
	
	FILE *infile = fopen( filename, "rb" );
	
	if ( !infile )
	{
		abort_("Error opening input jpeg file %s!\n", filename);
	}
	/* here we set up the standard libjpeg error handler */
	cinfo.err = jpeg_std_error( &jerr );
	jpeg_create_decompress( &cinfo );
	/* this makes the library read from infile */
	jpeg_stdio_src( &cinfo, infile );
	/* reading the image header which contains image information */
	jpeg_read_header( &cinfo, TRUE );


	/* Start decompression jpeg here */
	jpeg_start_decompress( &cinfo );
	width = cinfo.output_width;
	height = cinfo.output_height;
	num_components = cinfo.out_color_components;
	color_space = cinfo.out_color_space;
	
	
	/* allocate memory to hold the uncompressed image */
	size_t rowbytes = width * num_components;
	row_pointers = (JSAMPARRAY) malloc(sizeof(j_common_ptr) * height);
	for (y=0; y<height; y++){
		row_pointers[y] = (JSAMPROW) malloc(rowbytes);
	}
	
	
	/* read one scan line at a time */
	y=0;
	JSAMPARRAY tmp = row_pointers;
	while( cinfo.output_scanline < cinfo.image_height )
	{
		y = jpeg_read_scanlines( &cinfo, tmp, 1 );
		tmp +=y;
	}
	/* wrap up decompression, destroy objects, free pointers and close open files */
	jpeg_finish_decompress( &cinfo );
	jpeg_destroy_decompress( &cinfo );
// 	free( row_pointer[0] );
	fclose( infile );
	/* yup, we succeeded! */
}




/**
 * write_jpeg_file Writes the raw image data stored in the raw_image buffer
 * to a jpeg image with default compression and smoothing options in the file
 * specified by *filename.
 *
 * \returns positive integer if successful, -1 otherwise
 * \param *filename char string specifying the file name to save to
 *
 */
void write_jpeg_file( const char *filename )
{
	struct jpeg_compress_struct cinfo;
	struct jpeg_error_mgr jerr;
	int y;
	JSAMPARRAY tmp;

	
	/* this is a pointer to one row of image data */
	FILE *outfile = fopen( filename, "wb" );
	
	if ( !outfile )	{
		abort_("Error opening output jpeg file %s!\n", filename );
	}
	cinfo.err = jpeg_std_error( &jerr );
	jpeg_create_compress(&cinfo);
	jpeg_stdio_dest(&cinfo, outfile);

	/* Setting the parameters of the output file here */
	cinfo.image_width = width;	
	cinfo.image_height = height;
	cinfo.input_components = num_components;
	cinfo.in_color_space = color_space;
    /* default compression parameters, we shouldn't be worried about these */
	jpeg_set_defaults( &cinfo );
	jpeg_set_quality (&cinfo, quality, TRUE);
	/* Now do the compression .. */
	jpeg_start_compress( &cinfo, TRUE );
	/* like reading a file, this time write one row at a time */
	tmp = row_pointers;
	while( cinfo.next_scanline < cinfo.image_height )
	{
		y = jpeg_write_scanlines( &cinfo, tmp, 1 );
		tmp +=y;
	}
	/* similar to read file, clean up after we're done compressing */
	jpeg_finish_compress( &cinfo );
	jpeg_destroy_compress( &cinfo );
	fclose( outfile );
	
        /* cleanup heap allocation */
	for (y=0; y<height; y++){
		free(row_pointers[y]);
	}
	free(row_pointers);
}




int main(int argc, char **argv){   
  // Options
  struct arg_file *input_file_arg = arg_file1("i", "in-file", "<input>", "Input JPEG File");
  struct arg_file *output_file_arg = arg_file1("o", "out-file" , "<output>", "Output JPEG File");
  struct arg_str *filter_arg = arg_str1("f", "filter" , "<filter>", "Filter");
  struct arg_dbl *times_arg = arg_dbl0("t", "times" , "<times>", "Multiplyer");
  struct arg_dbl *contrast_arg = arg_dbl0("c", "contrast" , "<contrast>", "how much you want to change contrast");
  struct arg_dbl *percent_arg = arg_dbl0("p", "percent" , "<percent>", "Percent for brightness");
  struct arg_lit *sepia_arg = arg_lit0("s", "sepia", "Sepia filter");
  struct arg_lit *help = arg_lit0("h","help", "print this help and exit");
  struct arg_end *end = arg_end(10); // maksymalna liczba błędów 10
  
  int nerrors;
  
  void *argtable[] = {
    percent_arg,
    contrast_arg,
    sepia_arg,
    input_file_arg,
    output_file_arg,
    filter_arg,
    times_arg,
    help,
    end
};
  
  if (arg_nullcheck(argtable) != 0) printf("error: insufficient memory\n");
  
  times_arg->dval[0] = 1;
	percent_arg->dval[0] = 0;
	contrast_arg->dval[0] = 1;
  
  nerrors = arg_parse(argc, argv, argtable);

  if (help->count > 0){
     printf("Usage: point");
     arg_print_syntax(stdout, argtable,"\n");
     arg_print_glossary(stdout, argtable,"  %-25s %s\n");
     arg_freetable(argtable, sizeof(argtable)/sizeof(argtable[0]));
     return 0;
  }

  
  if (nerrors==0){
    input_file = input_file_arg->filename[0];
    output_file = output_file_arg->filename[0];

    filter = filter_arg->sval[0];

    times = times_arg->dval[0];
    percent = percent_arg->dval[0];
    contrast_value = contrast_arg->dval[0];
  }
  else{
     arg_print_errors(stderr, end, "point");
     arg_print_glossary(stderr, argtable, " %-25s %s\n");
     arg_freetable(argtable, sizeof(argtable)/sizeof(argtable[0]));
     return 1;
  }


   read_jpeg_file(input_file);
   process_file();
   write_jpeg_file(output_file);
   arg_freetable(argtable, sizeof(argtable)/sizeof(argtable[0]));
   return 0;
}