#include <locale.h>
#include <langinfo.h>
#include "postgres_fe.h"
//#include "miscadmin.h"
#include "mb/pg_wchar.h"

/*
 * Checks whether the encoding selected for PostgreSQL and the
 * encoding used by the system locale match.
 */

struct encoding_match
{
	enum pg_enc pg_enc_code;
	const char *system_enc_name;
};

static const struct encoding_match encoding_match_list[] = {
	{PG_EUC_JP, "EUC-JP"},
	{PG_EUC_JP, "eucJP"},
	{PG_EUC_JP, "IBM-eucJP"},
	{PG_EUC_JP, "sdeckanji"},

	{PG_EUC_CN, "EUC-CN"},
	{PG_EUC_CN, "eucCN"},
	{PG_EUC_CN, "IBM-eucCN"},
	{PG_EUC_CN, "GB2312"},
	{PG_EUC_CN, "dechanzi"},

	{PG_EUC_KR, "EUC-KR"},
	{PG_EUC_KR, "eucKR"},
	{PG_EUC_KR, "IBM-eucKR"},
	{PG_EUC_KR, "deckorean"},
	{PG_EUC_KR, "5601"},

	{PG_EUC_TW, "EUC-TW"},
	{PG_EUC_TW, "eucTW"},
	{PG_EUC_TW, "IBM-eucTW"},
	{PG_EUC_TW, "cns11643"},

#ifdef NOT_VERIFIED
	{PG_JOHAB, "???"},
#endif

	{PG_UTF8, "UTF-8"},
	{PG_UTF8, "utf8"},

	{PG_LATIN1, "ISO-8859-1"},
	{PG_LATIN1, "ISO8859-1"},
	{PG_LATIN1, "iso88591"},

	{PG_LATIN2, "ISO-8859-2"},
	{PG_LATIN2, "ISO8859-2"},
	{PG_LATIN2, "iso88592"},

	{PG_LATIN3, "ISO-8859-3"},
	{PG_LATIN3, "ISO8859-3"},
	{PG_LATIN3, "iso88593"},

	{PG_LATIN4, "ISO-8859-4"},
	{PG_LATIN4, "ISO8859-4"},
	{PG_LATIN4, "iso88594"},

	{PG_LATIN5, "ISO-8859-9"},
	{PG_LATIN5, "ISO8859-9"},
	{PG_LATIN5, "iso88599"},

	{PG_LATIN6, "ISO-8859-10"},
	{PG_LATIN6, "ISO8859-10"},
	{PG_LATIN6, "iso885910"},

	{PG_LATIN7, "ISO-8859-13"},
	{PG_LATIN7, "ISO8859-13"},
	{PG_LATIN7, "iso885913"},

	{PG_LATIN8, "ISO-8859-14"},
	{PG_LATIN8, "ISO8859-14"},
	{PG_LATIN8, "iso885914"},

	{PG_LATIN9, "ISO-8859-15"},
	{PG_LATIN9, "ISO8859-15"},
	{PG_LATIN9, "iso885915"},

	{PG_LATIN10, "ISO-8859-16"},
	{PG_LATIN10, "ISO8859-16"},
	{PG_LATIN10, "iso885916"},

	{PG_WIN1252, "CP1252"},
	{PG_WIN1253, "CP1253"},
	{PG_WIN1254, "CP1254"},
	{PG_WIN1255, "CP1255"},
	{PG_WIN1256, "CP1256"},
	{PG_WIN1257, "CP1257"},
	{PG_WIN1258, "CP1258"},
#ifdef NOT_VERIFIED
	{PG_WIN874, "???"},
#endif
	{PG_KOI8R, "KOI8-R"},
	{PG_WIN1251, "CP1251"},
	{PG_WIN866, "CP866"},

	{PG_ISO_8859_5, "ISO-8859-5"},
	{PG_ISO_8859_5, "ISO8859-5"},
	{PG_ISO_8859_5, "iso88595"},

	{PG_ISO_8859_6, "ISO-8859-6"},
	{PG_ISO_8859_6, "ISO8859-6"},
	{PG_ISO_8859_6, "iso88596"},

	{PG_ISO_8859_7, "ISO-8859-7"},
	{PG_ISO_8859_7, "ISO8859-7"},
	{PG_ISO_8859_7, "iso88597"},

	{PG_ISO_8859_8, "ISO-8859-8"},
	{PG_ISO_8859_8, "ISO8859-8"},
	{PG_ISO_8859_8, "iso88598"},

	{PG_SQL_ASCII, NULL}		/* end marker */
};

static char *
get_encoding_from_locale(const char *ctype)
{
	char	   *save;
	char	   *sys;

	save = setlocale(LC_CTYPE, NULL);
	if (!save)
		return NULL;
	save = strdup(save);

	setlocale(LC_CTYPE, ctype);
	sys = nl_langinfo(CODESET);
	sys = strdup(sys);

	setlocale(LC_CTYPE, save);
	free(save);

	return sys;
}


static int
find_matching_encoding(const char *ctype, const char *sys)
{
//	char	   *sys;
	int			i;

	sys = get_encoding_from_locale(ctype);

	for (i = 0; encoding_match_list[i].system_enc_name; i++)
	{
		if (strcasecmp(sys, encoding_match_list[i].system_enc_name) == 0)
		{
//			free(sys);
			return encoding_match_list[i].pg_enc_code;
		}
	}

//	free(sys);
	return -1;
}


int main(int argc, char **argv)
{
	int enc;
	char	   *sys;

	if( argc != 2)
	{
		fprintf(stderr,"Invalid number of arguments.\n");
		return 1;
	}

	printf("%-23s ... ", argv[1]);

	sys = get_encoding_from_locale(argv[1]);
	printf("%-10s - ",sys);

	enc=find_matching_encoding(argv[1], sys);
	if( enc != -1 )
		printf("OK\n");
	else
		printf("NO MATCH\n");

	free(sys);
	return 0;
}