/*
 * $Id$
 */

/*
 * Harbour Project source code:
 * The Language API
 *
 * Copyright 1999 Victor Szakats <info@szelvesz.hu>
 * www - http://www.harbour-project.org
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version, with one exception:
 *
 * The exception is that if you link the Harbour Runtime Library (HRL)
 * and/or the Harbour Virtual Machine (HVM) with other files to produce
 * an executable, this does not by itself cause the resulting executable
 * to be covered by the GNU General Public License. Your use of that
 * executable is in no way restricted on account of linking the HRL
 * and/or HVM code into it.
 *
 * This program 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 General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA (or visit
 * their web site at http://www.gnu.org/).
 *
 */

#include "hbapi.h"
#include "hbapilng.h"

/* Always link in the default language */
HB_LANG_REQUEST( HB_LANG_DEFAULT );

/* NOTE: This is the maximum number of registered languages, later this can be 
         made dynamic. */
#define HB_LANG_MAX_ 64

#define HB_LANG_ITEM_ID_ID         0
#define HB_LANG_ITEM_ID_NAME       1
#define HB_LANG_ITEM_ID_NAMENAT    2
#define HB_LANG_ITEM_ID_RFCID      3
#define HB_LANG_ITEM_ID_CODEPAGE   4

static PHB_LANG s_langList[ HB_LANG_MAX_ ];
static PHB_LANG s_lang = NULL;

static int hb_langFindPos( char * pszID )
{
   int iPos;

   if( pszID != NULL )
   {
      for( iPos = 0; iPos < HB_LANG_MAX_; iPos++ )
      {
         if( s_langList[ iPos ] != NULL && strcmp( ( char * ) s_langList[ iPos ]->pItemList[ HB_LANG_ITEM_BASE_ID + HB_LANG_ITEM_ID_ID ], pszID ) == 0 )
            return iPos;
      }
   }

   return -1;
}

BOOL hb_langRegister( PHB_LANG lang )
{
   HB_TRACE(HB_TR_DEBUG, ("hb_langRegister(%p)", lang));

   if( lang )
   {
      int iPos = hb_langFindPos( ( char * ) lang->pItemList[ HB_LANG_ITEM_BASE_ID + HB_LANG_ITEM_ID_ID ] );

      if( iPos == -1 )
      {
         for( iPos = 0; iPos < HB_LANG_MAX_; iPos++ )
         {
            if( s_langList[ iPos ] == NULL )
            {
               s_langList[ iPos ] = lang;
               return TRUE;
            }
         }
      }
      else
      {
         s_langList[ iPos ] = lang;
         return TRUE;
      }
   }

   return FALSE;
}

BOOL hb_langDeRegister( char * pszID )
{
   int iPos;

   HB_TRACE(HB_TR_DEBUG, ("hb_langDeRegister(%s)", pszID));

   iPos = hb_langFindPos( pszID );

   if( iPos != -1 )
   {
      s_langList[ iPos ] = NULL;
      return TRUE;
   }
   else
      return FALSE;
}

PHB_LANG hb_langFind( char * pszID )
{
   int iPos;

   HB_TRACE(HB_TR_DEBUG, ("hb_langFind(%s)", pszID));

   iPos = hb_langFindPos( pszID );

   return ( iPos != -1 ) ? s_langList[ iPos ] : NULL;
}

PHB_LANG hb_langSelect( PHB_LANG lang )
{
   PHB_LANG langOld = s_lang;

   HB_TRACE(HB_TR_DEBUG, ("hb_langSelect(%p)", lang));

   if( lang )
      s_lang = lang;

   return langOld;
}

char * hb_langSelectID( char * pszID )
{
   char * pszIDOld = hb_langID();

   HB_TRACE(HB_TR_DEBUG, ("hb_langSelectID(%s)", pszID));

   hb_langSelect( hb_langFind( pszID ) );

   return pszIDOld;
}

void * hb_langDGetItem( int iIndex )
{
   HB_TRACE(HB_TR_DEBUG, ("hb_langDGetItem(%i)", iIndex));

   if( s_lang && iIndex >= 0 && iIndex < HB_LANG_ITEM_MAX_ )
      return s_lang->pItemList[ iIndex ];
   else
      return NULL;
}

char * hb_langID( void )
{
   HB_TRACE(HB_TR_DEBUG, ("hb_langID()"));

   if( s_lang )
      return ( char * ) hb_langDGetItem( HB_LANG_ITEM_BASE_ID + HB_LANG_ITEM_ID_ID );
   else
      return NULL;
}

/* NOTE: Caller must free the pointer. */

char * hb_langName( void )
{
   char * pszName = ( char * ) hb_xgrab( 128 );

   if( s_lang )
      sprintf( pszName, "Harbour Language: %s %s (%s)", 
         ( char * ) hb_langDGetItem( HB_LANG_ITEM_BASE_ID + HB_LANG_ITEM_ID_ID ),
         ( char * ) hb_langDGetItem( HB_LANG_ITEM_BASE_ID + HB_LANG_ITEM_ID_NAME ),
         ( char * ) hb_langDGetItem( HB_LANG_ITEM_BASE_ID + HB_LANG_ITEM_ID_NAMENAT ) );
   else
      strcpy( pszName, "Harbour Language: (not installed)" );

   return pszName;
}

/* Compatibility interface */

char * hb_langDGetErrorDesc( ULONG ulIndex )
{
   HB_TRACE(HB_TR_DEBUG, ("hb_langDGetErrorDesc(%lu)", ulIndex));

   return ( char * ) hb_langDGetItem( HB_LANG_ITEM_BASE_ERRDESC + ulIndex );
}

/* Harbour interface */

HB_FUNC( HB_LANGSELECT )
{
   hb_retc( hb_langID() );

   hb_langSelectID( hb_parc( 1 ) );
}

HB_FUNC( HB_LANGNAME )
{
   char * pszName = hb_langName();
   hb_retc( pszName );
   hb_xfree( pszName );
}

