#define WINVER 0x0600
#include <stdio.h>
#include <windows.h>
#include <getopt.h>

#define VERSION  "1.0"

extern char *__progname;

void version () __attribute__ ((noreturn));
void usage (FILE *, int) __attribute__ ((noreturn));

void
version ()
{
  printf ("%s (Cygwin) %s\n", __progname, VERSION);
  exit (0);
}

void
usage (FILE * stream, int status)
{
  fprintf (stream, "\n\
Usage: %s [-suU] [-l LCID]\n\
\n\
Return POSIX LANG identifier corresponding to a locale, default is the\n\
system default locale\n\
Possible options are:\n\
\n\
  -s, --system      return LANG for the system's default locale\n\
  -u, --user        return LANG for the current user's default locale\n\
  -l, --lcid LCID   return LANG for the LCID given as argument\n\
  -U, --UTF-8       always attach .UTF-8 to LANG\n\
  -h, --help        this text\n\
  -V, --version     print the version of %s and exit\n",
	   __progname, __progname);
  exit (status);
}

struct option longopts[] = {
  {"system", no_argument, NULL, 's'},
  {"user", no_argument, NULL, 'u'},
  {"lcid", required_argument, NULL, 'l'},
  {"UTF-8", no_argument, NULL, 'U'},
  {"help", no_argument, NULL, 'h'},
  {"version", no_argument, NULL, 'V'},
  {"testloop", no_argument, NULL, 'T'},
  {0, no_argument, NULL, 0}
};
char *opts = "dsul:UhV";

int
getlocale (LCID lcid, bool utf, bool test)
{
  UINT codepage;
  char iso639[10];
  char iso3166[10];

  if (!GetLocaleInfo (lcid, LOCALE_IDEFAULTANSICODEPAGE | LOCALE_RETURN_NUMBER,
		      (char *) &codepage, sizeof codepage)
      || !GetLocaleInfo (lcid, LOCALE_SISO639LANGNAME, iso639, 10)
      || !GetLocaleInfo (lcid, LOCALE_SISO3166CTRYNAME, iso3166, 10))
    {
      if (!test)
        fprintf (stderr, "%s: Non existant locale\n", __progname);
      return 2;
    }
  if (utf)
    codepage = 0;
  if (test)
    {
      char cty[256];
      char lang[256];
      GetLocaleInfo (lcid, LOCALE_SENGCOUNTRY, cty, 256);
      GetLocaleInfo (lcid, LOCALE_SENGLANGUAGE, lang, 256);
      printf ("0x%04x=\"%s_%s\", %s (%s)\n", (unsigned) lcid, iso639, iso3166,
	      lang, cty);
    }
  else
    printf ("LANG=\"%s_%s%s\"\n", iso639, iso3166, codepage ? "" : ".UTF-8");
  return 0;
}

#define d(X)	{X, #X}
struct dl {
  LCTYPE t;
  const char *s;
} dlist[] = {
  d(LOCALE_SLONGDATE),
  d(LOCALE_SSHORTDATE),
  d(LOCALE_STIMEFORMAT),
  d(LOCALE_SYEARMONTH),
  d(LOCALE_S1159),
  d(LOCALE_S2359),
  d(LOCALE_SDAYNAME1),
  d(LOCALE_SDAYNAME2),
  d(LOCALE_SDAYNAME3),
  d(LOCALE_SDAYNAME4),
  d(LOCALE_SDAYNAME5),
  d(LOCALE_SDAYNAME6),
  d(LOCALE_SDAYNAME7),
  d(LOCALE_SABBREVDAYNAME1),
  d(LOCALE_SABBREVDAYNAME2),
  d(LOCALE_SABBREVDAYNAME3),
  d(LOCALE_SABBREVDAYNAME4),
  d(LOCALE_SABBREVDAYNAME5),
  d(LOCALE_SABBREVDAYNAME6),
  d(LOCALE_SABBREVDAYNAME7),
  d(LOCALE_SMONTHNAME1),
  d(LOCALE_SMONTHNAME2),
  d(LOCALE_SMONTHNAME3),
  d(LOCALE_SMONTHNAME4),
  d(LOCALE_SMONTHNAME5),
  d(LOCALE_SMONTHNAME6),
  d(LOCALE_SMONTHNAME7),
  d(LOCALE_SMONTHNAME8),
  d(LOCALE_SMONTHNAME9),
  d(LOCALE_SMONTHNAME10),
  d(LOCALE_SMONTHNAME11),
  d(LOCALE_SMONTHNAME12),
  d(LOCALE_SMONTHNAME13),
  d(LOCALE_SABBREVMONTHNAME1),
  d(LOCALE_SABBREVMONTHNAME2),
  d(LOCALE_SABBREVMONTHNAME3),
  d(LOCALE_SABBREVMONTHNAME4),
  d(LOCALE_SABBREVMONTHNAME5),
  d(LOCALE_SABBREVMONTHNAME6),
  d(LOCALE_SABBREVMONTHNAME7),
  d(LOCALE_SABBREVMONTHNAME8),
  d(LOCALE_SABBREVMONTHNAME9),
  d(LOCALE_SABBREVMONTHNAME10),
  d(LOCALE_SABBREVMONTHNAME11),
  d(LOCALE_SABBREVMONTHNAME12),
  d(LOCALE_SABBREVMONTHNAME13),
  { 0, NULL }
};

int main (int argc, char **argv)
{
  int opt;
  LCID lcid = LOCALE_SYSTEM_DEFAULT;
  bool utf = false;
  bool test = false;
  bool dates = false;

  while ((opt = getopt_long (argc, argv, opts, longopts, NULL)) != EOF)
    switch (opt)
      {
      case 's':
	lcid = LOCALE_SYSTEM_DEFAULT;
	break;
      case 'u':
	lcid = LOCALE_USER_DEFAULT;
	break;
      case 'l':
	lcid = strtoul (optarg, NULL, 0);
	break;
      case 'U':
	utf = true;
	break;
      case 'h':
	usage (stdout, 0);
	break;
      case 'V':
	version ();
	break;
      case 'T':
        test = true;
	break;
      case 'd':
        dates = true;
	break;
      default:
	usage (stderr, 1);
	break;
      }
  if (test)
    {
      for (unsigned lang = 1; lang <= 0x3ff; ++lang)
	for (unsigned sublang = 1; sublang <= 0x3f; ++sublang)
	  getlocale ((sublang << 10) | lang, false, true);
      return 0;
    }
  if (dates)
    {
      char buf[256];
      for (dl *dp = dlist; dp->t; ++dp)
	if (GetLocaleInfo (lcid, dp->t, buf, 256))
	  printf ("%s: <%s>\n", dp->s, buf);
      return 0;
    }
  return getlocale (lcid, utf, false);
}