/*
** Copyright 2011, Oliver Tappe <zooey@hirschkaefer.de>. All rights reserved.
** Distributed under the terms of the MIT License.
*/

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

#include <errno_private.h>
#include <LocaleBackend.h>


//#define TRACE_WCRTOMB
#ifdef TRACE_WCRTOMB
#       include <OS.h>
#       define TRACE(x) debug_printf x
#else
#       define TRACE(x) ;
#endif


using BPrivate::Libroot::GetCurrentLocaleBackend;
using BPrivate::Libroot::LocaleBackend;


extern "C" size_t
__wcrtomb(char* s, wchar_t wc, mbstate_t* ps)
{
        LocaleBackend* backend = GetCurrentLocaleBackend();

        if (ps == NULL) {
                static mbstate_t internalMbState;
                ps = &internalMbState;
        }

        if (s == NULL)
                wc = 0;

        if (backend == NULL) {
                /*
                 * The POSIX locale is active. Since the POSIX locale only contains
                 * chars 0-127 and those ASCII chars are compatible with the UTF32
                 * values used in wint_t, we can just return the byte.
                 */

                if (wc > 127) {
                        // char is non-ASCII
                        __set_errno(EILSEQ);
                        return (size_t)-1;
                }

                if (s != NULL)
                        *s = char(wc);

                return 1;
        }

        size_t lengthUsed;
        status_t status = backend->WcharToMultibyte(s, wc, ps, lengthUsed);

        if (status == B_BAD_INDEX)
                return (size_t)-2;

        if (status == B_BAD_DATA) {
                TRACE(("mbrtowc(): setting errno to EILSEQ\n"));
                __set_errno(EILSEQ);
                return (size_t)-1;
        }

        if (status != B_OK) {
                TRACE(("wcrtomb(): setting errno to EINVAL (status: %lx)\n", status));
                __set_errno(EINVAL);
                return (size_t)-1;
        }

        return lengthUsed;
}


B_DEFINE_WEAK_ALIAS(__wcrtomb, wcrtomb);