#include <cmath>
#include <cstring>
#include <iostream>
#include <allegro.h>

/**********************************************************/

void rgb16convert(BITMAP *bmp)
{
	int color, r, g, b;
	for (int y = 0; y < bmp->h; y++)
	{
		for (int x = 0; x < bmp->w; x++)
		{
			color = _getpixel32(bmp, x, y);
			r = getr32(color); g = getg32(color); b = getb32(color);
			r = ((r + 4) >> 3) << 3;
			g = ((g + 2) >> 2) << 2;
			b = ((b + 4) >> 3) << 3;
			if (r > 255) r = 255;
			if (g > 255) g = 255;
			if (b > 255) b = 255;
			_putpixel32(bmp, x, y, makecol32(r, g, b));
		}
	}	
}

void hsv16convert(BITMAP *bmp)
{
	int color, r, g, b;
	float h, s, v;
	for (int y = 0; y < bmp->h; y++)
	{
		for (int x = 0; x < bmp->w; x++)
		{
			color = _getpixel32(bmp, x, y);
			r = getr32(color); g = getg32(color); b = getb32(color);
			rgb_to_hsv(r, g, b, &h, &s, &v);
			h = std::floor((h * (16.0 / 360.0)) + 0.5) * (360.0 / 16.0);
			s = std::floor(s * 16.0 + 0.5) / 16.0;
			v = std::floor(v * 256.0 + 0.5) / 256.0;
			if (h > 360.0) h = 0.0;
			if (s > 1.0)   s = 1.0;
			if (v > 1.0)   v = 1.0;
			
			hsv_to_rgb(h, s, v, &r, &g, &b);
			_putpixel32(bmp, x, y, makecol32(r, g, b));
		}
	}
}

void hsv547convert(BITMAP *bmp)
{
	int color, r, g, b;
	float h, s, v;
	for (int y = 0; y < bmp->h; y++)
	{
		for (int x = 0; x < bmp->w; x++)
		{
			color = _getpixel32(bmp, x, y);
			r = getr32(color); g = getg32(color); b = getb32(color);
			rgb_to_hsv(r, g, b, &h, &s, &v);
			h = std::floor((h * (32.0 / 360.0)) + 0.5) * (360.0 / 32.0);
			s = std::floor(s * 16.0 + 0.5) / 16.0;
			v = std::floor(v * 128.0 + 0.5) / 128.0;
			if (h > 360.0) h = 0.0;
			if (s > 1.0)   s = 1.0;
			if (v > 1.0)   v = 1.0;
			
			hsv_to_rgb(h, s, v, &r, &g, &b);
			_putpixel32(bmp, x, y, makecol32(r, g, b));
		}
	}
}

void hsv646convert(BITMAP *bmp)
{
	int color, r, g, b;
	float h, s, v;
	for (int y = 0; y < bmp->h; y++)
	{
		for (int x = 0; x < bmp->w; x++)
		{
			color = _getpixel32(bmp, x, y);
			r = getr32(color); g = getg32(color); b = getb32(color);
			rgb_to_hsv(r, g, b, &h, &s, &v);
			h = std::floor((h * (64.0 / 360.0)) + 0.5) * (360.0 / 64.0);
			s = std::floor(s * 16.0 + 0.5) / 16.0;
			v = std::floor(v * 64.0 + 0.5) / 64.0;
			if (h > 360.0) h = 0.0;
			if (s > 1.0)   s = 1.0;
			if (v > 1.0)   v = 1.0;
			
			hsv_to_rgb(h, s, v, &r, &g, &b);
			_putpixel32(bmp, x, y, makecol32(r, g, b));
		}
	}
}

/**********************************************************/

int main(int argc, char **argv)
{
	if (argc != 4)
	{
		std::cerr << "Usage: cvt rgb565/hsv448/hsv547/hsv646 <input file> <output file>" << std::endl;
		return -1;
	}
	
	allegro_init();
	
	set_color_depth(32);
	set_gfx_mode(GFX_AUTODETECT_WINDOWED, 160, 160, 0, 0);
	
	BITMAP *bmp = load_bitmap(argv[2], NULL);
	if (!bmp)
	{
		std::cerr << "Couldn't load bitmap" << std::endl;
		return -1;
	}
	
	if (strcmp(argv[1], "rgb565") == 0)
		rgb16convert(bmp);
	else if (strcmp(argv[1], "hsv448") == 0)
		hsv16convert(bmp);
	else if (strcmp(argv[1], "hsv547") == 0)
		hsv547convert(bmp);
	else if (strcmp(argv[1], "hsv646") == 0)
		hsv646convert(bmp);
	else
	{
		std::cerr << "I don't know this format: " << argv[1] << std::endl;
		return -1;
	}
	
	save_bitmap(argv[3], bmp, NULL);
	
	return 0;
}
END_OF_MAIN()