#include <stdio.h>
#include "dct.h"

#define ENCODE 0
#define DECODE 1
#define MAXROWS 1024
#define MAXCOLS 768
#define HEADER	56

#define SOI_MK	0xFFD8		/* start of image	*/
#define SOF_MK	0xFFC0		/* start of frame	*/
#define EOI_MK	0xFFD9		/* end of image		*/
#define DRI_MK	0xFFDD		/* restart interval	*/

#define get_size(fi) (((unsigned int)Image1[fi]) << 8) + (unsigned int)Image1[fi+1]

unsigned char Image1[MAXCOLS*3*MAXROWS+HEADER];

unsigned char clip(int value) {
   if (value < 0) return (char) 0;
   if (value > 255) return (char) 255;
   return (unsigned char) value;
}

/* RGB -> YCbCr (also from BMP to JPEG) */
// Y = 0.299 R + 0.587 G + 0.114 B
unsigned char RGB2Y (unsigned char R, unsigned char G, unsigned char B) {
   return  clip(0.299 * R + 0.587 * G + 0.114 * B);
}

// Cb = - 0.1687 R - 0.3313 G + 0.5 B + 128
unsigned char RGB2Cb (unsigned char R, unsigned char G, unsigned char B) {
   return  clip(- 0.1687 * R - 0.3313 * G + 0.5 * B + 128);
}

//Cr = 0.5 R - 0.4187 G - 0.0813 B + 128
unsigned char RGB2Cr (unsigned char R, unsigned char G, unsigned char B) {
   return  clip(0.5 * R - 0.4187 * G - 0.0813 * B + 128);
}


/* RGB -> YCbCr (also from JPEG to BMP) */
// R = Y + 1.402 (Cr-128)
unsigned char YCbCr2R (unsigned char Y, unsigned char Cr) {
   return  clip(Y + 1.402 *(Cr-128));
}

// G = Y - 0.34414 (Cb-128) - 0.71414 (Cr-128)
unsigned char YCbCr2G (unsigned char Y, unsigned char Cb, unsigned char Cr) {
   return  clip(Y - 0.34414 *(Cb-128) - 0.71414 *(Cr-128));
}

// B = Y + 1.772 (Cb-128)
unsigned char YCbCr2B (unsigned char Y, unsigned char Cb) {
   return  clip(Y + 1.772 *(Cb-128));
}



int main(int argc, char *argv[]) {
	int retval, i;
	int workspace[DCTSIZE_BLOCK];
	int type, hCounter = 0;
	int x_size, y_size, offset, depth;

	char *fileIn, *fileOut;
	FILE *fI, *fO;
	unsigned char ch, mrgb[3];
	unsigned int aux;

/*******************************************************************************************/
/*	Just for testing on the PC		*/
	if(argc != 4)
	{
		printf("need more arguments");
		return 0;
	}

  	type = atoi(argv[1]);
    fileIn = argv[2];
  	fileOut = argv[3];

  	if (NULL == (fI = fopen(fileIn, "rb"))){
  	  printf("unable to open the file to read from (%s)",fileIn);
  	  return 0;
  	}
  	if ((fO = fopen(fileOut,"wb")) == NULL) {
  	  printf("unable to open the file to write (%s)",fileOut);
  	  return 0;
  	}

	/*		Read the max possible size to the memory			*/
	fread(Image1, sizeof(unsigned char), (MAXROWS*MAXCOLS*3+HEADER), fI);
/*******************************************************************************************/

/* The image must be in the memory by now	*/

	switch(type) {
		case ENCODE:
        offset = ((int)Image1[13] << 24) + ((int)Image1[12] << 16) + ((int)Image1[11] << 8) + Image1[10];
        x_size = ((int)Image1[21] << 24) + ((int)Image1[20] << 16) + ((int)Image1[19] << 8) + Image1[18];
        y_size = ((int)Image1[25] << 24) + ((int)Image1[24] << 16) + ((int)Image1[23] << 8) + Image1[22];
        depth = ((int)Image1[29] << 8) + Image1[28];

/**/    printf("Image Resolution: %d x %d x %i Offset: %i\n", x_size, y_size, depth, offset);

		break;
		case DECODE:

  	/* First find the SOI marker: */
  		aux = get_size(hCounter); hCounter+=2;
  		if (aux != SOI_MK)
  		{ printf("INFO:\tNO SOI marker!\n"); return 0;}

    	printf("%ld:\tINFO:\tFound the SOI marker!\n", hCounter);

		/* Read first marker */
		while( aux != SOF_MK)
		{
			aux = get_size(hCounter); hCounter+=2;
			if(aux == SOF_MK)
			{
			  get_size(hCounter); hCounter+=2;	/* header size, don't care */

	    	  /* load basic image parameters */
	    	  hCounter++;	/* precision, 8bit, don't care */
	    	  y_size = get_size(hCounter); hCounter+=2;
	    	  x_size = get_size(hCounter); hCounter+=2;

	    	  printf("\tINFO:\tImage size is %d by %d\n", x_size, y_size);

	    	  depth = Image1[hCounter];	/* # of components */

			  printf("\tINFO:\t");
			  switch (depth)
			  {
			  	  case 1:
			      printf("Monochrome");
			      break;
			  	  case 3:
			      printf("Color");
			      break;
			  	  default:
			  	    printf("Not a");
			      break;
			    }
			  printf(" JPEG image!\n");

	    	  return 0;
			}
			else
			{
				hCounter = hCounter + get_size(hCounter);
			}
		}
}


	retval = 0;
	type = ENCODE;

	switch(type) {
	case ENCODE:
		// RGB -> YUV

		// Convert to 8x8

		// DCT
		fdct(workspace);

		// ZZ

		// Q

		// VLC (huffman)

	break;
	case DECODE:
		// VLD (huffman)

		// IQ

		// ZZ

		// IDCT
		//idct(workspace);
		// Convert 8x8 to lines

		// YUV -> RGB

	break;
	}

	return retval;
}