/**
 * Copyright (c) 2009-2010 Mika Laitio <lamikr@pilppa.org>
 *
 * This file and library is covered by the LGPL version 3, read LICENSE for details.
 *
 * History:
 * - Created charencoding.c on: Nov 25, 2009
 */

#include <errno.h>
#include <stdarg.h>
#include <stdbool.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <iconv.h>

#include "internal/charencoding_internal.h"
#include "internal/utf8.h"

#define LOCALE_CHARSET_UTF8 "UTF-8"

static bool _locale_charset_utf8_check_initialized	= false;
static bool _locale_is_utf8				= false;

bool is_utf8_locale()
{
	const char *locale_charset;

	if (_locale_charset_utf8_check_initialized == false) {
		locale_charset = get_locale_charset_alias();
		if (strcmp(locale_charset, LOCALE_CHARSET_UTF8) == 0) {
			_locale_is_utf8 = true;
		}
		else {
			_locale_is_utf8	= false;
		}
		_locale_charset_utf8_check_initialized = true;
	}
	return _locale_is_utf8;
}

char *str_encode(const char *src,
		const char *src_charset,
		const char *trgt_charset,
		int *err_flg)
{
	iconv_t	conversion_desc;
	char	*ret_val;
	int	cmp_res;
	size_t 	src_length;
	size_t	trgt_length;

	ret_val 	= NULL;
	*err_flg	= 0;
	if (src != NULL) {
		cmp_res	= strcasecmp(src_charset,
				 trgt_charset);
		if ((cmp_res == 0) ||
		    (strlen(src) == 0)) {
			ret_val	= strdup(src);
			if (ret_val == NULL) {
				*err_flg	= ENOMEM;
			}
		}
		else {
			conversion_desc	= iconv_open(trgt_charset,
						src_charset);
			if (conversion_desc != (iconv_t)-1) {
				src_length	= strlen(src);
				trgt_length	= 0;
				ret_val		= str_iconv_encode(conversion_desc,
								src,
								src_length,
								&trgt_length,
								err_flg);
				if (*err_flg == 0) {
					*err_flg	= iconv_close(conversion_desc);
				}
				else {
					if (ret_val != NULL) {
						free(ret_val);
						ret_val	= NULL;
					}
				}
			}
			else {
				*err_flg	= ENOMEM;
			}
		}
	}
	return ret_val;
}

char *utf8_encode(char *src,
		int *err_flg)
{
	const char	*charset;
	char		*ret_val;

	ret_val = NULL;
	if (src != NULL) {
		if (is_utf8_locale() == true) {
			ret_val = strdup(src);
		}
		else {
			charset = get_locale_charset_alias();
			ret_val = str_encode(src,
					charset,
					LOCALE_CHARSET_UTF8,
					err_flg);
		}
	}
	return ret_val;
}

int utf8_printf(char *fmt, ...)
{
	int	ret_val;
	va_list args;

	va_start(args, fmt);
	{
		ret_val	= utf8_vprintf(fmt, args);
	}
	va_end(args);
	return ret_val;
}