/* SPDX-License-Identifier: GPL-3.0-or-later */
/* Copyright (C) 2021 KikooDX */

#include "strtocolor.h"
#include "info.h"
#include <raylib.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#define HEX_TABLE_SIZE 16
static const int hex_table[HEX_TABLE_SIZE] = {
    '0', '1', '2', '3', '4', '5', '6', '7',
    '8', '9', 'a', 'b', 'c', 'd', 'e', 'f'};
static const char *format_error =
    "ERROR: flag expected a color argument in the form #RRGGBB, got "
    "\"%s\"\n";

/* Attempt to convert a string to raylib Color. */
Color strtocolor(char *string)
{
	int rgb[3] = {0, 0, 0};
	char *character = string + (string[0] == '#');
	const size_t string_len = strlen(character);
	int i = 0;
	int sum = 0;

	if (string_len != 6) {
		fprintf(stderr, format_error, string);
		exit(EXIT_FAILURE);
	}

	while (*character != '\0') {
		int value = -1;
		int j;
		for (j = 0; j < HEX_TABLE_SIZE; j += 1) {
			if (hex_table[j] == *character) {
				value = j;
				break;
			}
		}
		if (value == -1) {
			fprintf(stderr, format_error, string);
			exit(EXIT_FAILURE);
		}
		sum += value * (1 + 15 * (i % 2));
		INFO_VAR("%d", sum);
		if (i % 2) {
			rgb[i / 2] = sum;
			sum = 0;
		}
		i += 1;
		character += 1;
	}
	INFO_VAR("r=%d", rgb[0]);
	INFO_VAR("g=%d", rgb[1]);
	INFO_VAR("b=%d", rgb[2]);
	return (Color){rgb[0], rgb[1], rgb[2], 255};
}