/*
 * Copyright © 2023 Nick Bowler
 *
 * Simplified mbsnwidth for test purposes.
 *
 * License WTFPL2: Do What The Fuck You Want To Public License, version 2.
 * This is free software: you are free to do what the fuck you want to.
 * There is NO WARRANTY, to the extent permitted by law.
 */

#include <string.h>
#include <locale.h>
#include <wchar.h>

#include "mbswidth.h"

int mbsnwidth(const char *buf, size_t buflen, int flags)
{
	static int initialized;
	mbstate_t ps;
	int ret = 0;

	if (!initialized) {
		setlocale(LC_CTYPE, "");
		initialized = 1;
	}

	memset(&ps, 0, sizeof ps);
	while (buflen > 0) {
		wchar_t wc;
		size_t l;
		int w;

		l = mbrtowc(&wc, buf, buflen, &ps);
		if (l == (size_t)-1 || l == (size_t)-2)
			return -1;
		else if (l == 0)
			break;

		buflen -= l;
		buf += l;

		w = wcwidth(wc);
		if (w < 0)
			return -1;
		ret += w;
	}

	return ret;
}