/* compile with:
 * gcc -o pgm2dng -m32 pgm2dng.c /path/to/magic-lantern/src/chdk-dng.c -I/path/to/magic-lantern/src -lm
 */

/*
 * Copyright (C) 2013 Magic Lantern Team
 * 
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or (at your option) any later version.
 * 
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 * 
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the
 * Free Software Foundation, Inc.,
 * 51 Franklin Street, Fifth Floor,
 * Boston, MA  02110-1301, USA.
 */

#include "stdint.h"
#include "stdio.h"
#include "stdlib.h"
#include "string.h"
#include "math.h"
#include "raw.h"
#include "chdk-dng.h"

struct raw_info raw_info;

#define FAIL(fmt,...) { fprintf(stderr, "Error: "); fprintf(stderr, fmt, ## __VA_ARGS__); fprintf(stderr, "\n"); exit(1); }
#define CHECK(ok, fmt,...) { if (!ok) FAIL(fmt, ## __VA_ARGS__); }

void raw_set_geometry(int width, int height, int skip_left, int skip_right, int skip_top, int skip_bottom)
{
    raw_info.width = width;
    raw_info.height = height;
    raw_info.pitch = raw_info.width * raw_info.bits_per_pixel / 8;
    raw_info.frame_size = raw_info.height * raw_info.pitch;
    raw_info.active_area.x1 = skip_left;
    raw_info.active_area.y1 = skip_top;
    raw_info.active_area.x2 = raw_info.width - skip_right;
    raw_info.active_area.y2 = raw_info.height - skip_bottom;
    raw_info.jpeg.x = 0;
    raw_info.jpeg.y = 0;
    raw_info.jpeg.width = raw_info.width - skip_left - skip_right;
    raw_info.jpeg.height = raw_info.height - skip_top - skip_bottom;
}

//~ { "Nikon D5100", 0, 0x3de6,
//~ { 8198,-2239,-724,-4871,12389,2798,-1043,2050,7181 } },
//~ { "Canon EOS 5D Mark III", 0, 0x3c80,
//~ { 6722,-635,-963,-4287,12460,2028,-908,2162,5668 } },
#define CAM_COLORMATRIX1                       \
     6722, 10000,     -635, 10000,    -963, 10000, \
    -4287, 10000,    12460, 10000,    2028, 10000, \
     -908, 10000,     2162, 10000,    5668, 10000

struct raw_info raw_info = {
    .api_version = 1,
    .bits_per_pixel = 16,
    .black_level = 2048,
    .white_level = 16382,
    .cfa_pattern = 0x02010100,          // Red  Green  Green  Blue
    .calibration_illuminant1 = 1,       // Daylight
    .color_matrix1 = {CAM_COLORMATRIX1},// camera-specific, from dcraw.c
};

int main(int argc, char** argv)
{
    FILE* fp = fopen(argv[1], "rb");
    CHECK(fp, "could not open %s", argv[1]);

    /* PGM read code from dcraw */
    int dim[3]={0,0,0}, comment=0, number=0, error=0, nd=0, c;

      if (fgetc(fp) != 'P' || fgetc(fp) != '5') error = 1;
      while (!error && nd < 3 && (c = fgetc(fp)) != EOF) {
        if (c == '#')  comment = 1;
        if (c == '\n') comment = 0;
        if (comment) continue;
        if (isdigit(c)) number = 1;
        if (number) {
          if (isdigit(c)) dim[nd] = dim[nd]*10 + c -'0';
          else if (isspace(c)) {
        number = 0;  nd++;
          } else error = 1;
        }
      }
    
    CHECK(!(error || nd < 3), "not a valid PGM file\n");

    int width = dim[0];
    int height = dim[1];

    raw_set_geometry(width, height, 0, 0, 0, 0);
    
    printf("Resolution  : %d x %d\n", raw_info.width, raw_info.height);
    printf("Frame size  : %d bytes\n", raw_info.frame_size);
    printf("Black level : %d\n", raw_info.black_level);
    printf("White level : %d\n", raw_info.white_level);
    
    char* raw = malloc(raw_info.frame_size);
    CHECK(raw, "malloc");
    raw_info.buffer = raw;

    int size = fread(raw, 1, width * height * 2, fp);
    CHECK(size == width * height * 2, "fread");
    fclose(fp);
    
    char fo[50];
    int n = snprintf(fo, sizeof(fo), "%s", argv[1]);
    fo[n-3] = 'D';
    fo[n-2] = 'N';
    fo[n-1] = 'G';
    
    printf("Output file : %s\n", fo);
    save_dng(fo, &raw_info);
    printf("Done.\n");
    return 0;
}

int raw_get_pixel(int x, int y)
{
    /* fixme: return valid values here to create a thumbnail */
    return 0;
}