/*
 * Copyright (c) 2020 Jiri Svoboda
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * - Redistributions of source code must retain the above copyright
 *   notice, this list of conditions and the following disclaimer.
 * - Redistributions in binary form must reproduce the above copyright
 *   notice, this list of conditions and the following disclaimer in the
 *   documentation and/or other materials provided with the distribution.
 * - The name of the author may not be used to endorse or promote products
 *   derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

/** @addtogroup libgfxfont
 * @{
 */
/**
 * @file Glyph bitmap
 */

#include <errno.h>
#include <gfx/bitmap.h>
#include <gfx/coord.h>
#include <gfx/glyph_bmp.h>
#include <io/pixelmap.h>
#include <stdlib.h>
#include "../private/font.h"
#include "../private/glyph.h"
#include "../private/glyph_bmp.h"

static errno_t gfx_glyph_bmp_extend(gfx_glyph_bmp_t *, gfx_coord2_t *);

/** Open glyph bitmap for editing.
 *
 * @param glyph Glyph
 * @param rbmp Place to store glyph bitmap
 * @return EOK on success, ENOMEM if out of memory
 */
errno_t gfx_glyph_bmp_open(gfx_glyph_t *glyph, gfx_glyph_bmp_t **rbmp)
{
	gfx_font_t *font = glyph->font;
	gfx_glyph_bmp_t *bmp;
	pixelmap_t pmap;
	gfx_bitmap_alloc_t alloc;
	gfx_coord_t x, y;
	pixel_t pixel;
	errno_t rc;

	bmp = calloc(1, sizeof(gfx_glyph_bmp_t));
	if (bmp == NULL)
		return ENOMEM;

	/* Bitmap coordinates are relative to glyph origin point */
	gfx_rect_rtranslate(&glyph->origin, &glyph->rect, &bmp->rect);

	bmp->pixels = calloc((bmp->rect.p1.x - bmp->rect.p0.x) *
	    (bmp->rect.p1.y - bmp->rect.p0.y), sizeof(int));
	if (bmp->pixels == NULL) {
		free(bmp);
		return ENOMEM;
	}

	rc = gfx_bitmap_get_alloc(font->bitmap, &alloc);
	if (rc != EOK) {
		free(bmp->pixels);
		free(bmp);
		return rc;
	}

	assert(font->rect.p0.x == 0);
	assert(font->rect.p0.y == 0);
	pmap.width = font->rect.p1.x;
	pmap.height = font->rect.p1.y;
	pmap.data = alloc.pixels;

	/* Copy pixels from font bitmap */

	for (y = bmp->rect.p0.y; y < bmp->rect.p1.y; y++) {
		for (x = bmp->rect.p0.x; x < bmp->rect.p1.x; x++) {
			pixel = pixelmap_get_pixel(&pmap, glyph->origin.x + x,
			    glyph->origin.y + y);
			bmp->pixels[(y - bmp->rect.p0.y) *
			    (bmp->rect.p1.x - bmp->rect.p0.x) +
			    (x - bmp->rect.p0.x)] = (pixel != 0) ? 1 : 0;
		}
	}

	bmp->glyph = glyph;
	*rbmp = bmp;
	return EOK;
}

/** Save glyph bitmap.
 *
 * @param bmp Glyph bitmap
 * @return EOK on success, ENOMEM if out of memory
 */
errno_t gfx_glyph_bmp_save(gfx_glyph_bmp_t *bmp)
{
	gfx_glyph_t *glyph = bmp->glyph;
	gfx_font_t *font = glyph->font;
	gfx_coord_t x, y;
	gfx_rect_t used_rect;
	pixel_t pixel;
	pixelmap_t pmap;
	gfx_bitmap_alloc_t alloc;
	errno_t rc;

	/* Find actual rectangle being used */
	gfx_glyph_bmp_find_used_rect(bmp, &used_rect);

	/*
	 * Replace glyph with empty space in the font bitmap, the width
	 * of the empty equal to new glyph bitmap width. The glyph width
	 * is adjusted.
	 */
	rc = gfx_font_splice_at_glyph(font, glyph, &used_rect);
	if (rc != EOK)
		return rc;

	rc = gfx_bitmap_get_alloc(font->bitmap, &alloc);
	if (rc != EOK)
		return rc;

	assert(font->rect.p0.x == 0);
	assert(font->rect.p0.y == 0);
	pmap.width = font->rect.p1.x;
	pmap.height = font->rect.p1.y;
	pmap.data = alloc.pixels;

	/* Copy pixels to font bitmap */

	for (y = used_rect.p0.y; y < used_rect.p1.y; y++) {
		for (x = used_rect.p0.x; x < used_rect.p1.x; x++) {
			pixel = bmp->pixels[(y - bmp->rect.p0.y) *
			    (bmp->rect.p1.x - bmp->rect.p0.x) +
			    (x - bmp->rect.p0.x)] ?
			    PIXEL(255, 255, 255, 255) : PIXEL(0, 0, 0, 0);
			pixelmap_put_pixel(&pmap, glyph->origin.x + x,
			    glyph->origin.y + y, pixel);
		}
	}

	return EOK;
}

/** Close glyph bitmap.
 *
 * @param bmp Glyph bitmap
 */
void gfx_glyph_bmp_close(gfx_glyph_bmp_t *bmp)
{
	free(bmp->pixels);
	free(bmp);
}

/** Get rectangle covered by glyph bitmap.
 *
 * @param bmp Glyph bitmap
 * @param rect Place to store rectangle
 */
void gfx_glyph_bmp_get_rect(gfx_glyph_bmp_t *bmp, gfx_rect_t *rect)
{
	*rect = bmp->rect;
}

/** Find minimum rectangle covering all non-background pixels.
 *
 * @param bmp Glyph bitmap
 * @param rect Place to store rectangle
 */
void gfx_glyph_bmp_find_used_rect(gfx_glyph_bmp_t *bmp, gfx_rect_t *rect)
{
	gfx_coord_t x, y;
	gfx_coord2_t min;
	gfx_coord2_t max;
	bool anypix;
	int pix;

	min.x = bmp->rect.p1.x;
	min.y = bmp->rect.p1.y;
	max.x = bmp->rect.p0.x;
	max.y = bmp->rect.p0.y;

	anypix = false;
	for (y = bmp->rect.p0.y; y < bmp->rect.p1.y; y++) {
		for (x = bmp->rect.p0.x; x < bmp->rect.p1.x; x++) {
			pix = gfx_glyph_bmp_getpix(bmp, x, y);
			if (pix != 0) {
				anypix = true;
				if (x < min.x)
					min.x = x;
				if (y < min.y)
					min.y = y;
				if (x > max.x)
					max.x = x;
				if (y > max.y)
					max.y = y;
			}
		}
	}

	if (anypix) {
		rect->p0.x = min.x;
		rect->p0.y = min.y;
		rect->p1.x = max.x + 1;
		rect->p1.y = max.y + 1;
	} else {
		rect->p0.x = 0;
		rect->p0.y = 0;
		rect->p1.x = 0;
		rect->p1.y = 0;
	}
}

/** Get pixel from glyph bitmap.
 *
 * @param bmp Glyph bitmap
 * @param x X-coordinate
 * @param y Y-coordinate
 * @return Pixel value
 */
int gfx_glyph_bmp_getpix(gfx_glyph_bmp_t *bmp, gfx_coord_t x, gfx_coord_t y)
{
	gfx_coord2_t pos;
	size_t pitch;

	pos.x = x;
	pos.y = y;
	if (!gfx_pix_inside_rect(&pos, &bmp->rect))
		return 0;

	pitch = bmp->rect.p1.x - bmp->rect.p0.x;

	return bmp->pixels[(y - bmp->rect.p0.y) * pitch +
	    (x - bmp->rect.p0.x)];
}

/** Set pixel in glyph bitmap.
 *
 * @param bmp Glyph bitmap
 * @param x X-coordinate
 * @param y Y-coordinate
 *
 * @reutrn EOK on success, ENOMEM if out of memory
 */
errno_t gfx_glyph_bmp_setpix(gfx_glyph_bmp_t *bmp, gfx_coord_t x,
    gfx_coord_t y, int value)
{
	gfx_coord2_t pos;
	size_t pitch;
	errno_t rc;

	pos.x = x;
	pos.y = y;

	if (!gfx_pix_inside_rect(&pos, &bmp->rect)) {
		rc = gfx_glyph_bmp_extend(bmp, &pos);
		if (rc != EOK)
			return rc;
	}

	pitch = bmp->rect.p1.x - bmp->rect.p0.x;
	bmp->pixels[(y - bmp->rect.p0.y) * pitch +
	    (x - bmp->rect.p0.x)] = value;
	return EOK;
}

/** Clear glyph bitmap
 *
 * @param bmp Glyph bitmap
 *
 * @return EOK on sucesss, ENOMEM if out of memory
 */
errno_t gfx_glyph_bmp_clear(gfx_glyph_bmp_t *bmp)
{
	int *npixels;

	/* Allocate new pixel array */
	npixels = calloc(sizeof(int), 1);
	if (npixels == NULL)
		return ENOMEM;

	/* Switch new and old data */
	free(bmp->pixels);
	bmp->pixels = npixels;
	bmp->rect.p0.x = 0;
	bmp->rect.p0.y = 0;
	bmp->rect.p1.x = 0;
	bmp->rect.p1.y = 0;

	return EOK;
}

/** Extend glyph bitmap to cover a patricular pixel.
 *
 * @param bmp Glyph bitmap
 * @param pos Pixel position
 *
 * @return EOK on sucesss, ENOMEM if out of memory
 */
static errno_t gfx_glyph_bmp_extend(gfx_glyph_bmp_t *bmp, gfx_coord2_t *pos)
{
	gfx_rect_t prect;
	gfx_rect_t nrect;
	int *npixels;
	size_t npitch;
	size_t opitch;
	gfx_coord_t x, y;

	/* Compute new rectangle enveloping current rectangle and new pixel */
	prect.p0 = *pos;
	prect.p1.x = prect.p0.x + 1;
	prect.p1.y = prect.p0.y + 1;

	gfx_rect_envelope(&bmp->rect, &prect, &nrect);

	/* Allocate new pixel array */
	npixels = calloc(sizeof(int), (nrect.p1.x - nrect.p0.x) *
	    (nrect.p1.y - nrect.p0.y));
	if (npixels == NULL)
		return ENOMEM;

	/* Transfer pixel data */
	opitch = bmp->rect.p1.x - bmp->rect.p0.x;
	npitch = nrect.p1.x - nrect.p0.x;

	for (y = bmp->rect.p0.y; y < bmp->rect.p1.y; y++) {
		for (x = bmp->rect.p0.x; x < bmp->rect.p1.x; x++) {
			npixels[(y - nrect.p0.y) * npitch + x - nrect.p0.x] =
			    bmp->pixels[(y - bmp->rect.p0.y) * opitch +
			    x - bmp->rect.p0.x];
		}
	}

	/* Switch new and old data */
	free(bmp->pixels);
	bmp->pixels = npixels;
	bmp->rect = nrect;

	return EOK;
}

/** @}
 */