/*
 * Copyright (C) 2018 Tomasz Kramkowski <tk@the-tk.com>
 * SPDX-License-Identifier: MIT
 */
#include <ctype.h>
#include <stdbool.h>
#include <stdio.h>
#include <stdlib.h>

#include "eprintf.h"

#ifndef VERSION
#define VERSION "v0.1"
#endif

enum {
	ALIGN = 16,
};

static const char *usage = "[-hv] [--] output map input...";

static void help(void)
{
	fprintf(stderr,
		"Options:\n"
		"    -h  Show this help.\n"
		"    -v  Show version and license information.\n"
		"\n"
		"Please check the bie(1) man page for more information.\n");
}

static void version(void)
{
	fprintf(stderr,
		"bie %s\n"
		"Copyright (C) 2018 Tomasz Kramkowski <tk@the-tk.com>\n"
		"Licensed under the MIT license <https://opensource.org/licenses/MIT>\n"
		"There is NO WARRANTY, to the extent permitted by law.\n",
		VERSION);
}

static void slug(FILE *f, const char *text)
{
	bool leading = true;
	int c;

	while (c = *text++, c != '\0') {
		if (isalpha(c)) {
			leading = false;
			fputc(c, f);
			continue;
		}
		if (leading) continue;
		if (isdigit(c))
			fputc(c, f);
		else if (ispunct(c) || isspace(c))
			fputc('_', f);
	}
}

static void mapentry(FILE *map, const char *name, size_t pos, size_t size)
{
	fprintf(map, "BIE_ENTRY(");
	slug(map, name);
	fprintf(map, ", %zu, %zu)\n", pos, size);
}

static size_t dumpfile(FILE *dest, FILE *src)
{
	size_t size = 0;
	int c;

	while (c = fgetc(src), c != EOF) {
		size++;
		fputc(c, dest);
	}

	return size;
}

int main(int argc, char **argv)
{
	const char *argv0 = argv[0] != NULL ? argv[0] : "bie";
	FILE *dest, *map;
	size_t pos = 0;

	setprogname(argv0);

	for (argv++, argc--; argv[0] != NULL && argv[0][0] == '-' &&
		     argv[0][1] != '-' && argv[0][2] == '\0'; argv++, argc--) {
		switch (argv[0][1]) {
		case 'h':
			fprintf(stderr, "Usage: %s %s\n", argv0, usage);
			help();
			return EXIT_SUCCESS;
		case 'v':
			version();
			return EXIT_SUCCESS;
		}
	}

	if (argc < 3)
		eprintf("Invalid argument count\nUsage: %s %s", argv0, usage);

	dest = fopen(argv[0], "wb");
	if (dest == NULL)
		eprintf("Could not open `%s':", argv[0]);

	map = fopen(argv[1], "w");
	if (map == NULL)
		eprintf("Could not open `%s':", argv[1]);

	for (int i = 2; i < argc; i++) {
		size_t size;
		FILE *src;

		src = fopen(argv[i], "rb");
		if (src == NULL)
			eprintf("Could not open `%s':", argv[i]);
		size = dumpfile(dest, src);
		fclose(src);
		mapentry(map, argv[i], pos, size);
		pos += size;
		if (pos % ALIGN) {
			size_t pad = ALIGN - pos % ALIGN;
			for (size_t i = 0; i < pad; i++)
				fputc(0, dest);
			pos += pad;
		}
	}

	fclose(map);
	fclose(dest);
}