/*
 * Copyright (c) 2026 Faraz Vahedi <kfv@kfv.io>
 *
 * SPDX-License-Identifier: BSD-2-Clause
 */

#include <ctype.h>
#include <stdlib.h>

#include "strfrom.h"

int
strfromd(char * __restrict s, size_t n, const char * __restrict fmt, double fp)
{
        char conv, lc, *digits, *dend;
        int prec, decpt, signflag, ret, mode, ndig_req;

        conv = __sf_parse_fmt(fmt, &prec);
        if (conv == '\0')
                return (__sf_edoofus(s, n));
        lc = tolower((unsigned char)conv);

        if (lc == 'a') {
                digits = __hdtoa(fp, __sf_xdigits(conv),
                    prec >= 0 ? prec + 1 : -1, &decpt, &signflag, &dend);
                ret = __sf_render_hex(s, n, conv, prec, digits, dend, decpt,
                    signflag);
                freedtoa(digits);
                return (ret);
        }

        if (prec < 0)
                prec = 6;

        __sf_decimal_mode(lc, prec, &mode, &ndig_req);

        digits = dtoa(fp, mode, ndig_req, &decpt, &signflag, &dend);

        ret = __sf_render_decimal(s, n, conv, lc, prec, digits, dend, decpt,
            signflag, decpt == 9999);

        freedtoa(digits);

        return (ret);
}