#include <fitz.h>

fz_error *
fz_newpixmap(fz_pixmap **pixp, fz_colorspace *cs, int x, int y, int w, int h, int n, int a)
{
	fz_pixmap *pix;

	pix = *pixp = fz_malloc(sizeof (fz_pixmap));
	if (!pix)
		return fz_outofmem;

	pix->cs = cs;
	pix->x = x;
	pix->y = y;
	pix->w = w;
	pix->h = h;
	pix->n = n;
	pix->a = a;
	pix->stride = (pix->n + pix->a) * pix->w;

	pix->samples = fz_malloc(sizeof(unsigned char) * pix->stride * pix->h);
	if (!pix->samples) {
		fz_free(pix);
		return fz_outofmem;
	}

	memset(pix->samples, 0, sizeof(unsigned char) * pix->stride * pix->h);

	return nil;
}

void
fz_freepixmap(fz_pixmap *pix)
{
	fz_free(pix->samples);
	fz_free(pix);
}

void
fz_clearpixmap(fz_pixmap *pix)
{
	memset(pix->samples, 0, sizeof(unsigned char) * pix->stride * pix->h);
}

void
fz_debugpixmap(fz_pixmap *pix)
{
	int x, y;

	FILE *ppm = fopen("out.ppm", "w");
	FILE *pgm = fopen("out.pgm", "w");

	fprintf(ppm, "P6\n%d %d\n255\n", pix->w, pix->h);
	fprintf(pgm, "P5\n%d %d\n255\n", pix->w, pix->h);

	if (pix->n == 3 && pix->a == 1)
	{
		for (y = 0; y < pix->h; y++)
			for (x = 0; x < pix->w; x++)
			{
				int r = pix->samples[x * 4 + y * pix->stride + 0];
				int g = pix->samples[x * 4 + y * pix->stride + 1];
				int b = pix->samples[x * 4 + y * pix->stride + 2];
				int a = pix->samples[x * 4 + y * pix->stride + 3];

				//putc(r, ppm);
				//putc(g, ppm);
				//putc(b, ppm);
				putc(((r * a) / 255) + (255 - a), ppm);
				putc(((g * a) / 255) + (255 - a), ppm);
				putc(((b * a) / 255) + (255 - a), ppm);

				putc(a, pgm);
			}
	}
	else if (pix->n == 0 && pix->a == 1)
	{
		for (y = 0; y < pix->h; y++)
			for (x = 0; x < pix->w; x++)
			{
				int a = pix->samples[x + y * pix->stride];
				putc(0, ppm);
				putc(0, ppm);
				putc(0, ppm);
				putc(a, pgm);
			}
	}

	fclose(ppm);
	fclose(pgm);
}

void
fz_blendover(fz_pixmap *src, fz_pixmap *dst)
{
	int x, y;

	assert(dst->n == src->n);
	assert(dst->a == 1);
	assert(src->n == 3);
	assert(src->a == 1);

	for (y = 0; y < dst->h; y++)
	{
		unsigned char *s = &src->samples[y * src->stride];
		unsigned char *d = &dst->samples[y * dst->stride];

		for (x = 0; x < dst->w; x++)
		{
			int sa = s[3];
			int ssa = 255 - sa;

			d[0] = fz_mul255(s[0], sa) + fz_mul255(d[0], ssa);
			d[1] = fz_mul255(s[1], sa) + fz_mul255(d[1], ssa);
			d[2] = fz_mul255(s[2], sa) + fz_mul255(d[2], ssa);
			d[3] = sa + fz_mul255(d[3], ssa);

			s += 4;
			d += 4;
		}
	}
}

void
fz_blendmask(fz_pixmap *dst, fz_pixmap *src, fz_pixmap *msk)
{
	int x, y, k;

	assert(src->n == dst->n);
	assert(src->a == 1);
	assert(msk->n == 0);
	assert(msk->a == 1);
	assert(dst->a == 1);

	for (y = 0; y < dst->h; y++)
	{
		unsigned char *d = &dst->samples[y * dst->stride];
		unsigned char *s = &src->samples[y * src->stride];
		unsigned char *m = &msk->samples[y * msk->stride];

		for (x = 0; x < dst->w; x++)
		{
			for (k = 0; k < dst->n; k++)
				*d++ = *s++;
			*d++ = fz_mul255(*m++, *s++);
		}
	}
}