/*
 * Main command implementation routines for cdecl99.
 * Copyright © 2011-2012, 2020-2021, 2023-2024 Nick Bowler
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <https://www.gnu.org/licenses/>.
 */

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

#include "cdecl99.h"
#include "cdecl.h"

static struct cdecl *do_parse(const char *s, int input_mode)
{
	struct cdecl *parse;

	if (input_mode == INPUT_C)
		parse = cdecl_parse_decl(s);
	else
		parse = cdecl_parse_english(s);

	if (!parse)
		print_error("%s", cdecl_get_error()->str);

	return parse;
}

/*
 * Format a declaration according to the given function and return a pointer
 * to the formatted string.  The returned pointer remains valid until the
 * next call, after which it must not be re-used.
 *
 * Returns NULL on failure.
 */
static const char *do_render(struct cdecl *decl, int output_mode)
{
	static size_t bufsz;
	static char *buf;
	size_t rc;

retry:
	if (output_mode == OUTPUT_C)
		rc = cdecl_declare(buf, bufsz, decl);
	else
		rc = cdecl_explain(buf, bufsz, decl);

	if (rc >= bufsz) {
		char *tmp;

		tmp = realloc(buf, rc + 1);
		if (!tmp) {
			print_error("%s", _("failed to allocate memory"));
			return NULL;
		}

		buf = tmp;
		bufsz = rc + 1;
		goto retry;
	}

	return buf;
}

/*
 * Parse the given string as either C or English (based on input_mode),
 * then print the result as either C or English (based on output_mode).
 */
int run_command_cdecl(const char *s, int input_mode, int output_mode)
{
	struct cdecl *i, *parse;
	int ret = -1;

	if (!(parse = do_parse(s, input_mode)))
		goto out;

	for (i = parse; i; i = i->next) {
		const char *str;

		if (!(str = do_render(i, output_mode)))
			goto out;

		/*
		 * In C output, only the first declarator needs specifiers
		 * printed, and only the last declarator needs a newline.
		 */
		if (output_mode == OUTPUT_C && i->next) {
			i->next->specifiers = NULL;
			printf("%s, ", str);
		} else {
			puts(str);
		}
	}

	ret = 0;
out:
	cdecl_free(parse);
	return ret;
}