/* quirc -- QR-code recognition library
 * Copyright (C) 2010-2012 Daniel Beer <dlbeer@gmail.com>
 *
 * Permission to use, copy, modify, and/or distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */

#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#include <jpeglib.h>
#include <png.h>

#include <quirc.h>

#include "dbgutil.h"

static const char *data_type_str(int dt)
{
	switch (dt) {
	case QUIRC_DATA_TYPE_NUMERIC: return "NUMERIC";
	case QUIRC_DATA_TYPE_ALPHA:   return "ALPHA";
	case QUIRC_DATA_TYPE_BYTE:    return "BYTE";
	case QUIRC_DATA_TYPE_KANJI:   return "KANJI";
	}

	return "unknown";
}

void dump_data(const struct quirc_data *data)
{
	printf("    Version: %d\n", data->version);
	printf("    ECC level: %c\n", "MLHQ"[data->ecc_level]);
	printf("    Mask: %d\n", data->mask);
	printf("    Data type: %d (%s)\n",
	    data->data_type, data_type_str(data->data_type));
	printf("    Length: %d\n", data->payload_len);
	printf("    Payload: %s\n", data->payload);

	if (data->eci)
		printf("    ECI: %d\n", data->eci);
}

void dump_cells(const struct quirc_code *code)
{
	int u, v;

	printf("    %d cells, corners:", code->size);
	for (u = 0; u < 4; u++)
		printf(" (%d,%d)", code->corners[u].x,
				   code->corners[u].y);
	printf("\n");

	for (v = 0; v < code->size; v++) {
		printf("    ");
		for (u = 0; u < code->size; u++) {
			int p = v * code->size + u;

			if (code->cell_bitmap[p >> 3] & (1 << (p & 7)))
				printf("[]");
			else
				printf("  ");
		}
		printf("\n");
	}
}

struct my_jpeg_error {
	struct jpeg_error_mgr   base;
	jmp_buf                 env;
};

static void my_output_message(struct jpeg_common_struct *com)
{
	struct my_jpeg_error *err = (struct my_jpeg_error *)com->err;
	char buf[JMSG_LENGTH_MAX];

	err->base.format_message(com, buf);
	fprintf(stderr, "JPEG error: %s\n", buf);
}

static void my_error_exit(struct jpeg_common_struct *com)
{
	struct my_jpeg_error *err = (struct my_jpeg_error *)com->err;

	my_output_message(com);
	longjmp(err->env, 0);
}

static struct jpeg_error_mgr *my_error_mgr(struct my_jpeg_error *err)
{
	jpeg_std_error(&err->base);

	err->base.error_exit = my_error_exit;
	err->base.output_message = my_output_message;

	return &err->base;
}

int load_jpeg(struct quirc *q, const char *filename)
{
	FILE *infile = fopen(filename, "rb");
	struct jpeg_decompress_struct dinfo;
	struct my_jpeg_error err;
	uint8_t *image;
	int y;

	if (!infile) {
		perror("can't open input file");
		return -1;
	}

	memset(&dinfo, 0, sizeof(dinfo));
	dinfo.err = my_error_mgr(&err);

	if (setjmp(err.env))
		goto fail;

	jpeg_create_decompress(&dinfo);
	jpeg_stdio_src(&dinfo, infile);

	jpeg_read_header(&dinfo, TRUE);
	dinfo.output_components = 1;
	dinfo.out_color_space = JCS_GRAYSCALE;
	jpeg_start_decompress(&dinfo);

	if (dinfo.output_components != 1) {
		fprintf(stderr, "Unexpected number of output components: %d",
			 dinfo.output_components);
		goto fail;
	}

	if (quirc_resize(q, dinfo.output_width, dinfo.output_height) < 0)
		goto fail;

	image = quirc_begin(q, NULL, NULL);

	for (y = 0; y < dinfo.output_height; y++) {
		JSAMPROW row_pointer = image + y * dinfo.output_width;

		jpeg_read_scanlines(&dinfo, &row_pointer, 1);
	}

	jpeg_finish_decompress(&dinfo);
	fclose(infile);
	jpeg_destroy_decompress(&dinfo);
	return 0;

fail:
	fclose(infile);
	jpeg_destroy_decompress(&dinfo);
	return -1;
}

/* hacked from https://dev.w3.org/Amaya/libpng/example.c
 *
 * Check if a file is a PNG image using png_sig_cmp(). Returns 1 if the given
 * file is a PNG and 0 otherwise.
 */
#define PNG_BYTES_TO_CHECK 4
int check_if_png(const char *filename)
{
	int ret = 0;
	FILE *infile = NULL;
	unsigned char buf[PNG_BYTES_TO_CHECK];

	/* Open the prospective PNG file. */
	if ((infile = fopen(filename, "rb")) == NULL)
		goto out;

	/* Read in some of the signature bytes */
	if (fread(buf, 1, PNG_BYTES_TO_CHECK, infile) != PNG_BYTES_TO_CHECK)
		goto out;

	/*
	 * Compare the first PNG_BYTES_TO_CHECK bytes of the signature.
	 * png_sig_cmp() returns zero if the image is a PNG and nonzero if it
	 * isn't a PNG.
	 */
	if (png_sig_cmp(buf, (png_size_t)0, PNG_BYTES_TO_CHECK) == 0)
		ret = 1;

	/* FALLTHROUGH */
out:
	if (infile)
		fclose(infile);
	return (ret);
}

int load_png(struct quirc *q, const char *filename)
{
	int width, height, rowbytes, interlace_type, number_passes = 1;
	png_uint_32 trns;
	png_byte color_type, bit_depth;
	png_structp png_ptr = NULL;
	png_infop info_ptr = NULL;
	FILE *infile = NULL;
	uint8_t *image;
	int ret = -1;
	int pass;

	if ((infile = fopen(filename, "rb")) == NULL)
		goto out;

	png_ptr = png_create_read_struct(PNG_LIBPNG_VER_STRING, NULL, NULL, NULL);
	if (!png_ptr)
		goto out;

	info_ptr = png_create_info_struct(png_ptr);
	if (!info_ptr)
		goto out;

	if (setjmp(png_jmpbuf(png_ptr)))
		goto out;

	png_init_io(png_ptr, infile);

	png_read_info(png_ptr, info_ptr);

	color_type     = png_get_color_type(png_ptr, info_ptr);
	bit_depth      = png_get_bit_depth(png_ptr, info_ptr);
	interlace_type = png_get_interlace_type(png_ptr, info_ptr);

	// Read any color_type into 8bit depth, Grayscale format.
	// See http://www.libpng.org/pub/png/libpng-manual.txt

	// PNG_COLOR_TYPE_GRAY_ALPHA is always 8 or 16bit depth.
	if (color_type == PNG_COLOR_TYPE_GRAY && bit_depth < 8)
		png_set_expand_gray_1_2_4_to_8(png_ptr);

	if ((trns = png_get_valid(png_ptr, info_ptr, PNG_INFO_tRNS)))
		png_set_tRNS_to_alpha(png_ptr);

	if (bit_depth == 16)
#if PNG_LIBPNG_VER >= 10504
		png_set_scale_16(png_ptr);
#else
		png_set_strip_16(png_ptr);
#endif

	if ((trns) || color_type & PNG_COLOR_MASK_ALPHA)
		png_set_strip_alpha(png_ptr);

	if (color_type == PNG_COLOR_TYPE_PALETTE)
		png_set_palette_to_rgb(png_ptr);

	if (color_type == PNG_COLOR_TYPE_PALETTE ||
	    color_type == PNG_COLOR_TYPE_RGB ||
	    color_type == PNG_COLOR_TYPE_RGB_ALPHA) {
		png_set_rgb_to_gray_fixed(png_ptr, 1, -1, -1);
	}

	if (interlace_type != PNG_INTERLACE_NONE)
		number_passes = png_set_interlace_handling(png_ptr);

	png_read_update_info(png_ptr, info_ptr);

	width    = png_get_image_width(png_ptr, info_ptr);
	height   = png_get_image_height(png_ptr, info_ptr);
	rowbytes = png_get_rowbytes(png_ptr, info_ptr);
	if (rowbytes != width) {
		fprintf(stderr,
		    "load_png: expected rowbytes to be %u but got %u\n",
		    width, rowbytes);
		goto out;
	}

	if (quirc_resize(q, width, height) < 0)
		goto out;

	image = quirc_begin(q, NULL, NULL);

	for (pass = 0; pass < number_passes; pass++) {
		int y;

		for (y = 0; y < height; y++) {
			png_bytep row_pointer = image + y * width;
			png_read_rows(png_ptr, &row_pointer, NULL, 1);
		}
	}

	png_read_end(png_ptr, info_ptr);

	ret = 0;
	/* FALLTHROUGH */
out:
	/* cleanup */
	if (png_ptr) {
		if (info_ptr)
			png_destroy_read_struct(&png_ptr, &info_ptr, (png_infopp)NULL);
		else
			png_destroy_read_struct(&png_ptr, (png_infopp)NULL, (png_infopp)NULL);
	}
	if (infile)
		fclose(infile);
	return (ret);
}