#include "pixbuf_ops.h"
#include "colors.h"

/*
In general, for 0 <= i < width and 0 <= j < height, the pixel (x + i, y + j) is colored with red value rgb_buf[j * rowstride + i * 3], green value rgb_buf[j * rowstride + i * 3 + 1], and blue value rgb_buf[j * rowstride + i * 3 + 2].
*/

GdkPixbuf * select_rgb_composant( GdkPixbuf *original_pixbuf,
				  float red, float green, float blue)
{
     GdkPixbuf *red_pixbuf;
     guchar *pixels;
     int rowstride = gdk_pixbuf_get_rowstride (original_pixbuf);
     int width = gdk_pixbuf_get_width (original_pixbuf);
     int height = gdk_pixbuf_get_height (original_pixbuf);
     int i, j;
     /* copy the pixbuf */
     red_pixbuf = gdk_pixbuf_copy (original_pixbuf);

     pixels = gdk_pixbuf_get_pixels (red_pixbuf);

     for (i=0; i<width; i++)
	  for (j=0; j<height; j++)
	  {
	       float color = red   * pixels[j*rowstride+i*3] +
			     green * pixels[j*rowstride+i*3+1] +
		             blue  * pixels[j*rowstride+i*3+2];
	       pixels[j*rowstride+i*3]   = color;
	       pixels[j*rowstride+i*3+1] = color;
	       pixels[j*rowstride+i*3+2] = color;
	  }
     return red_pixbuf;
}


void pixbuf_rgb2hsl( GdkPixbuf *original_pixbuf,
		     GdkPixbuf **h_pixbuf, GdkPixbuf **s_pixbuf, GdkPixbuf **l_pixbuf )
{
     guchar *h_pixels, *s_pixels, *l_pixels;
     int rowstride = gdk_pixbuf_get_rowstride (original_pixbuf);
     int width = gdk_pixbuf_get_width (original_pixbuf);
     int height = gdk_pixbuf_get_height (original_pixbuf);
     guchar h, s, l;
     unsigned int i, j;

     /* copy the pixbuf */
     *h_pixbuf = gdk_pixbuf_copy (original_pixbuf);
     *s_pixbuf = gdk_pixbuf_copy (original_pixbuf);
     *l_pixbuf = gdk_pixbuf_copy (original_pixbuf);

     /* get pixbufs pixels */
     h_pixels = gdk_pixbuf_get_pixels (*h_pixbuf);
     s_pixels = gdk_pixbuf_get_pixels (*s_pixbuf);
     l_pixels = gdk_pixbuf_get_pixels (*l_pixbuf);

     for (i=0; i<width; i++)
	  for (j=0; j<height; j++)
	  {
	       /* we could use pixels from either original, h, s or l pixbufs since they're copies */
	       guchar *pixel = (guchar *) h_pixels + j*rowstride + i*3;
	       point_rgb2hsl(pixel, pixel+1, pixel+2, &h, &s, &l);

	       h_pixels[j*rowstride+i*3] = h_pixels[j*rowstride+i*3+1] = h_pixels[j*rowstride+i*3+2] = h;
	       s_pixels[j*rowstride+i*3] = s_pixels[j*rowstride+i*3+1] = s_pixels[j*rowstride+i*3+2] = s;
	       l_pixels[j*rowstride+i*3] = l_pixels[j*rowstride+i*3+1] = l_pixels[j*rowstride+i*3+2] = l;
	  }
}

void pixbuf_rgb2xyz( GdkPixbuf *original_pixbuf,
		     GdkPixbuf **x_pixbuf, GdkPixbuf **y_pixbuf, GdkPixbuf **z_pixbuf )
{
     guchar *x_pixels, *y_pixels, *z_pixels;
     int rowstride = gdk_pixbuf_get_rowstride (original_pixbuf);
     int width = gdk_pixbuf_get_width (original_pixbuf);
     int height = gdk_pixbuf_get_height (original_pixbuf);
     guchar x, y, z;
     unsigned int i, j;

     /* copy the pixbuf */
     *x_pixbuf = gdk_pixbuf_copy (original_pixbuf);
     *y_pixbuf = gdk_pixbuf_copy (original_pixbuf);
     *z_pixbuf = gdk_pixbuf_copy (original_pixbuf);

     /* get pixbufs pixels */
     x_pixels = gdk_pixbuf_get_pixels (*x_pixbuf);
     y_pixels = gdk_pixbuf_get_pixels (*y_pixbuf);
     z_pixels = gdk_pixbuf_get_pixels (*z_pixbuf);

     for (i=0; i<width; i++)
	  for (j=0; j<height; j++)
	  {
	       /* we could use pixels from either original, x, y or z pixbufs since they're copies */
	       guchar *pixel = (guchar *) x_pixels + j*rowstride + i*3;
	       point_rgb2xyz(pixel, pixel+1, pixel+2, &x, &y, &z);

	       x_pixels[j*rowstride+i*3] = x_pixels[j*rowstride+i*3+1] = x_pixels[j*rowstride+i*3+2] = x;
	       y_pixels[j*rowstride+i*3] = y_pixels[j*rowstride+i*3+1] = y_pixels[j*rowstride+i*3+2] = y;
	       z_pixels[j*rowstride+i*3] = z_pixels[j*rowstride+i*3+1] = z_pixels[j*rowstride+i*3+2] = z;
	  }
}

void pixbuf_rgb2luv( GdkPixbuf *original_pixbuf,
		     GdkPixbuf **l_pixbuf, GdkPixbuf **u_pixbuf, GdkPixbuf **v_pixbuf )
{
     guchar *l_pixels, *u_pixels, *v_pixels;
     int rowstride = gdk_pixbuf_get_rowstride (original_pixbuf);
     int width = gdk_pixbuf_get_width (original_pixbuf);
     int height = gdk_pixbuf_get_height (original_pixbuf);
     guchar l, u, v;
     unsigned int i, j;

     /* copy the pixbuf */
     *l_pixbuf = gdk_pixbuf_copy (original_pixbuf);
     *u_pixbuf = gdk_pixbuf_copy (original_pixbuf);
     *v_pixbuf = gdk_pixbuf_copy (original_pixbuf);

     /* get pixbufs pixels */
     l_pixels = gdk_pixbuf_get_pixels (*l_pixbuf);
     u_pixels = gdk_pixbuf_get_pixels (*u_pixbuf);
     v_pixels = gdk_pixbuf_get_pixels (*v_pixbuf);

     for (i=0; i<width; i++)
	  for (j=0; j<height; j++)
	  {
	       /* we could use pixels from either original, l, u or v pixbufs since they're copies */
	       guchar *pixel = (guchar *) l_pixels + j*rowstride + i*3;
	       point_rgb2luv(pixel, pixel+1, pixel+2, &l, &u, &v);

	       l_pixels[j*rowstride+i*3] = l_pixels[j*rowstride+i*3+1] = l_pixels[j*rowstride+i*3+2] = l;
	       u_pixels[j*rowstride+i*3] = u_pixels[j*rowstride+i*3+1] = u_pixels[j*rowstride+i*3+2] = u;
	       v_pixels[j*rowstride+i*3] = v_pixels[j*rowstride+i*3+1] = v_pixels[j*rowstride+i*3+2] = v;
	  }
}

void pixbuf_rgb2lab( GdkPixbuf *original_pixbuf,
		     GdkPixbuf **l_pixbuf, GdkPixbuf **a_pixbuf, GdkPixbuf **b_pixbuf )
{
     guchar *l_pixels, *a_pixels, *b_pixels;
     int rowstride = gdk_pixbuf_get_rowstride (original_pixbuf);
     int width = gdk_pixbuf_get_width (original_pixbuf);
     int height = gdk_pixbuf_get_height (original_pixbuf);
     guchar l, a, b;
     unsigned int i, j;

     /* copy the pixbuf */
     *l_pixbuf = gdk_pixbuf_copy (original_pixbuf);
     *a_pixbuf = gdk_pixbuf_copy (original_pixbuf);
     *b_pixbuf = gdk_pixbuf_copy (original_pixbuf);

     /* get pixbufs pixels */
     l_pixels = gdk_pixbuf_get_pixels (*l_pixbuf);
     a_pixels = gdk_pixbuf_get_pixels (*a_pixbuf);
     b_pixels = gdk_pixbuf_get_pixels (*b_pixbuf);

     for (i=0; i<width; i++)
	  for (j=0; j<height; j++)
	  {
	       /* we could use pixels from either original, l, a or b pixbufs since they're copies */
	       guchar *pixel = (guchar *) l_pixels + j*rowstride + i*3;
	       point_rgb2lab(pixel, pixel+1, pixel+2, &l, &a, &b);

	       l_pixels[j*rowstride+i*3] = l_pixels[j*rowstride+i*3+1] = l_pixels[j*rowstride+i*3+2] = l;
	       a_pixels[j*rowstride+i*3] = a_pixels[j*rowstride+i*3+1] = a_pixels[j*rowstride+i*3+2] = a;
	       b_pixels[j*rowstride+i*3] = b_pixels[j*rowstride+i*3+1] = b_pixels[j*rowstride+i*3+2] = b;
	  }
}

GdkPixbuf * video_effect( GdkPixbuf *original_pixbuf )
{
     GdkPixbuf *video_pixbuf;
     guchar *pixels;
     int rowstride = gdk_pixbuf_get_rowstride (original_pixbuf);
     int width = gdk_pixbuf_get_width (original_pixbuf);
     int height = gdk_pixbuf_get_height (original_pixbuf);
     int i, j;
     int composant = 0;
     int color = 0;
     /* copy the pixbuf */
     video_pixbuf = gdk_pixbuf_copy (original_pixbuf);

     pixels = gdk_pixbuf_get_pixels (video_pixbuf);

     for (j=0; j<height; j++)
     {
	  for (i=0; i<width; i++)
	  {
	       composant = (pixels[j*rowstride+i*3] + pixels[j*rowstride+i*3+1] + pixels[j*rowstride+i*3+2]) / 3;
	       switch (color)
	       {
	       case 0:
		    pixels[j*rowstride+i*3] = composant;
		    pixels[j*rowstride+i*3+1] = 0;
		    pixels[j*rowstride+i*3+2] = 0;
		    break;
	       case 1:
		    pixels[j*rowstride+i*3] = 0;
		    pixels[j*rowstride+i*3+1] = composant;
		    pixels[j*rowstride+i*3+2] = 0;
		    break;
	       case 2:
		    pixels[j*rowstride+i*3] = 0;
		    pixels[j*rowstride+i*3+1] = 0;
		    pixels[j*rowstride+i*3+2] = composant;
		    break;
	       }
	  }
	  color = (color + 1)%3;
     }
     return video_pixbuf;
}