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

#include "error.h"
#include "jpeg_manip.h"

#ifdef WIN32
void pause(void)
{
	system("pause");
}
#endif

/***************************** main() ***********************************
Main function (see help for more details)
************************************************************************/
int main(int argc, char ** argv)
{
	int nbDCT = 0;
	int coef = 0;
	int i; // Loop variable
	int return_value;
	JPEGimg *img = NULL;
	DCTpos position = { 0 };

	// To pause the system at exit if run under windows
#ifdef WIN32
	atexit(pause);
#endif

	// Check number of arguments of the command line
	if (argc < 3)
	{
		printf("%s: Reads a jpeg image and write it in a new file\n", argv[0]);
		printf("Not enough arguments for %s\n", argv[0]);
		printf("Usage: %s <cover.jpg> <copy.jpg>\n", argv[0]);
		return EXIT_FAILURE;
	}

	srand((int)time(NULL));

	// read image
	img = jpeg_read(argv[1]);
	if (!img)
		return EXIT_FAILURE;

	// print some informations
	printf("Number of components: %d\n", img->cinfo.num_components);
	for (i = 0; i < img->cinfo.num_components; i++)
	{
		printf("Component %d:\n   %d lines, %d columns\n\n", i, img->cinfo.comp_info[i].height_in_blocks, img->cinfo.comp_info[i].width_in_blocks);
		//Rajout
		nbDCT += img->cinfo.comp_info[i].height_in_blocks * img->cinfo.comp_info[i].width_in_blocks;
	}
	nbDCT *= 64;
	printf("NbDCT = %d\n\n", nbDCT);

	for (int j = 0; j < img->cinfo.num_components; j++)
	{
		for (int k=0; k < img->cinfo.comp_info[j].height_in_blocks ; k++)
		{
			for (int f = 0; f < img->cinfo.comp_info[j].width_in_blocks; f++)
			{
				for (int i = 0; i < 64; i++)
				{
					if(img->dctCoeffs[j][k][f][1])
					{
						img->dctCoeffs[j][k][f][i]++;
						coef++;
					}
				}
			}
		}
	}

	coef = coef / nbDCT;
	//

	getDCTpos(img->dctCoeffs, &(img->cinfo), 0, &position);
	getDCTcoeffValue(img->dctCoeffs, &(img->cinfo), &position, &return_value);
	printf("First coefficient (comp 0, lin 0, col 0, coeff 0): %d\n", return_value);

	// set first coefficient to 0
	img->dctCoeffs[2][39][29][0] = 0;

	// write it in a new file
	return_value = jpeg_write_from_coeffs(argv[2], img);
	if (return_value == EXIT_SUCCESS)
		printf("\nImage written in %s\n", argv[2]);
	free_jpeg_img(img);

	return EXIT_SUCCESS;
}