//  This may look like C code, but it is really -*- C++ -*-

//  ------------------------------------------------------------------
//  The Goldware Library
//  Copyright (C) 1990-1999 Odinn Sorensen
//  ------------------------------------------------------------------
//  This library is free software; you can redistribute it and/or
//  modify it under the terms of the GNU Library General Public
//  License as published by the Free Software Foundation; either
//  version 2 of the License, or (at your option) any later version.
//
//  This library is distributed in the hope that it will be useful,
//  but WITHOUT ANY WARRANTY; without even the implied warranty of
//  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
//  Library General Public License for more details.
//
//  You should have received a copy of the GNU Library General Public
//  License along with this program; if not, write to the Free
//  Software Foundation, Inc., 59 Temple Place, Suite 330, Boston,
//  MA 02111-1307, USA
//  ------------------------------------------------------------------
//  $Id$
//  ------------------------------------------------------------------
//  String upper/lower and NLS functions.
//  ------------------------------------------------------------------

#include <gstrall.h>
#include <gutlmisc.h>


//  ------------------------------------------------------------------

int g_islower(int c)
{
  return isascii(c) ? islower(c) : (c == g_tolower(c)) && (c != g_toupper(c));
}

int g_isupper(int c)
{
  return isascii(c) ? isupper(c) : (c != g_tolower(c)) && (c == g_toupper(c));
}

int g_isalpha(int c)
{
  return isascii(c) ? isalpha(c) : (c != g_tolower(c)) || (c != g_toupper(c));
}

int isxalnum(int c)
{
  return isascii(c) ? isalnum(c) : (c != g_tolower(c)) || (c != g_toupper(c));
}

//  ------------------------------------------------------------------
//  Converts a character to upper or lower case depending on the
//  previous character in the string

static char touplow(char* str, char* pos, char ch) {

  char i;

  if(pos == str)
    return g_toupper(ch);

  switch(*(pos-1)) {                  // check previous character
    case ' ':                         // see if it is a separator
    case '-':
    case '_':
    case ',':
    case '.':
    case '/':
      i = (char)g_toupper(ch);        // if it is, convert to upper
      break;
    default:
      i = (char)g_tolower(ch);        // otherwise, convert to lower
      break;
  }

  return i;                           // return converted character
}


//  ------------------------------------------------------------------
//  Converts a string to mixed upper & lower case

char* struplow(char* str) {

  int i;

  for(i=0; *(str+i); i++)
    *(str+i) = touplow(str, str+i, *(str+i));

  return str;
}


//  ------------------------------------------------------------------

char* strcvtc(char* str) {

  char c;
  char* s = str;
  char* d = s;
  while(*s) {
    if(*s == '\\') {
      s++;
      switch(*s) {
        case 'n':  *d++ = '\n'; goto skip_constant;
        case 't':  *d++ = '\t'; goto skip_constant;
        case 'v':  *d++ = '\v'; goto skip_constant;
        case 'b':  *d++ = '\b'; goto skip_constant;
        case 'r':  *d++ = '\r'; goto skip_constant;
        case 'f':  *d++ = '\f'; goto skip_constant;
        case 'a':  *d++ = '\a'; goto skip_constant;
        case '\\': *d++ = '\\'; goto skip_constant;
        case '\'': *d++ = '\''; goto skip_constant;
        case '\"': *d++ = '\"'; goto skip_constant;
        case '\?': *d++ = '\?'; goto skip_constant;
        case 'x':
          if(isxdigit(s[1])) {
            s++;
            c = 0;
            while(isxdigit(*s)) {
              c <<= 4;
              c |= (char)xtoi(*s);
              s++;
            }
            *d++ = c;
            continue;
          }
          break;
        default:
          if(isoctal(*s)) {
            c = 0;
            while(isoctal(*s)) {
              c <<= 3;
              c |= (char)(*s - '0');
              s++;
            }
            *d++ = c;
          }
          else {
            s++;
            continue;
          }
      }
      *d++ = *s++;
      continue;

      skip_constant:
      s++;
      continue;
    }
    *d++ = *s++;
  }
  *d = NUL;
  return str;
}


//  ------------------------------------------------------------------