/*
 * RemAll(), RemLeft() and RemRight() CT3 string functions
 *
 * Copyright 2001 IntTec GmbH, Neunlindenstr 32, 79106 Freiburg, Germany
 *        Author: Martin Vogel <vogel@inttec.de>
 *
 * 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, or (at your option)
 * any later version.
 *
 * 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; see the file LICENSE.txt.  If not, write to
 * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
 * Boston, MA 02110-1301 USA (or visit https://www.gnu.org/licenses/).
 *
 * As a special exception, the Harbour Project gives permission for
 * additional uses of the text contained in its release of Harbour.
 *
 * The exception is that, if you link the Harbour libraries 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 Harbour library code into it.
 *
 * This exception does not however invalidate any other reasons why
 * the executable file might be covered by the GNU General Public License.
 *
 * This exception applies only to the code released by the Harbour
 * Project under the name Harbour.  If you copy code from other
 * Harbour Project or Free Software Foundation releases into a copy of
 * Harbour, as the General Public License permits, the exception does
 * not apply to the code that you add in this way.  To avoid misleading
 * anyone as to the status of such modified files, you must delete
 * this exception notice from them.
 *
 * If you write modifications of your own for Harbour, it is your choice
 * whether to permit this exception to apply to your modifications.
 * If you do not wish that, delete this exception notice.
 *
 */

#include "ct.h"

/* defines */
#define DO_REMOVE_REMALL    0
#define DO_REMOVE_REMLEFT   1
#define DO_REMOVE_REMRIGHT  2

static const HB_ERRCODE sulErrorSubcodes[] =
{
   CT_ERROR_REMALL,
   CT_ERROR_REMLEFT,
   CT_ERROR_REMRIGHT
};

/* helper function for the Rem*() functions */
static void do_remove( int iSwitch )
{
   /* param check */
   if( HB_ISCHAR( 1 ) )
   {
      const char * pcString = hb_parc( 1 );
      HB_SIZE sStrLen = hb_parclen( 1 );
      const char * pcRet;
      HB_SIZE sRetLen;
      char cSearch;

      if( hb_parclen( 2 ) > 0 )
         cSearch = *( hb_parc( 2 ) );
      else if( HB_ISNUM( 2 ) )
         cSearch = ( char ) ( hb_parnl( 2 ) % 256 );
      else
         cSearch = 0x20;

      sRetLen = sStrLen;
      pcRet = pcString;

      if( iSwitch != DO_REMOVE_REMRIGHT )
      {
         while( *pcRet == cSearch && pcRet < ( pcString + sStrLen ) )
         {
            pcRet++;
            sRetLen--;
         }
      }

      if( iSwitch != DO_REMOVE_REMLEFT )
      {
         const char * pc = pcString + sStrLen - 1;

         while( *pc == cSearch && pc >= pcRet )
         {
            pc--;
            sRetLen--;
         }
      }

      if( sRetLen == 0 )
         hb_retc_null();
      else
         hb_retclen( pcRet, sRetLen );
   }
   else
   {
      PHB_ITEM pSubst = NULL;
      int iArgErrorMode = ct_getargerrormode();

      if( iArgErrorMode != CT_ARGERR_IGNORE )
         pSubst = ct_error_subst( ( HB_USHORT ) iArgErrorMode, EG_ARG,
                                  sulErrorSubcodes[ iSwitch ],
                                  NULL, HB_ERR_FUNCNAME, 0,
                                  EF_CANSUBSTITUTE, HB_ERR_ARGS_BASEPARAMS );

      if( pSubst != NULL )
         hb_itemReturnRelease( pSubst );
      else
         hb_retc_null();
   }
}

HB_FUNC( REMALL )
{
   do_remove( DO_REMOVE_REMALL );
}

HB_FUNC( REMLEFT )
{
   do_remove( DO_REMOVE_REMLEFT );
}

HB_FUNC( REMRIGHT )
{
   do_remove( DO_REMOVE_REMRIGHT );
}