/*
 * $Id$
 */

/*
 * xHarbour Project source code:
 * Text file reading functions
 *
 * Copyright 2003 Marcelo Lombardo - lombardo@uol.com.br
 * http://www.xharbour.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, 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 software; see the file COPYING.  If not, write to
 * the Free Software Foundation, Inc., 59 Temple Place, Suite 330,
 * Boston, MA 02111-1307 USA (or visit the web site http://www.gnu.org/).
 *
 * 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 <ctype.h>

#include "hbapi.h"
#include "hbapifs.h"
#include "hb_io.h"
#include "hbset.h"
#include "hbapiitm.h"
#include "hbapierr.h"

#define READING_BLOCK      4096

BYTE * hb_fsReadLine( FHANDLE hFileHandle, LONG *plBuffLen, char ** Term, int * iTermSizes, USHORT iTerms, BOOL * bFound, BOOL *bEOF  )
{
   USHORT uiPosTerm = 0, iPos, uiPosition;
   USHORT nTries;
   LONG lRead = 0, lOffset, lSize;
   BYTE * pBuff;

   HB_TRACE(HB_TR_DEBUG, ("hb_fsReadLine(%p, %ld, %p, %p, %hu, %i, %i)", hFileHandle, *plBuffLen, Term, iTermSizes, iTerms, *bFound, *bEOF ));

   *bFound  = 0;
   *bEOF    = 0;
   nTries   = 0;
   lOffset  = 0;
   lSize   = *plBuffLen;

   if( *plBuffLen < 10 )
   {
      *plBuffLen = READING_BLOCK;
   }

   pBuff = (BYTE*) hb_xgrab( *plBuffLen );

   do
   {
      if(nTries>0)
      {
         /* pBuff can be enlarged to hold the line as needed.. */
         lSize = ( *plBuffLen * ( nTries + 1 ) ) + 1;
         pBuff = (BYTE *) hb_xrealloc( pBuff, lSize );
         lOffset += lRead;
      }

      /* read from file */
      lRead = hb_fsReadLarge( hFileHandle, pBuff + lOffset, lSize-lOffset );

      /* scan the read buffer */

      if (lRead>0)
      {
         for( iPos=0; iPos<lRead; iPos++ )
         {
            for( uiPosTerm=0;uiPosTerm < iTerms;uiPosTerm++)
            {
               /* Compare with the LAST terminator byte */
               if( pBuff[lOffset+iPos] == Term[uiPosTerm][iTermSizes[uiPosTerm]-1] && (iTermSizes[uiPosTerm]-1) <= (iPos+lOffset) )
               {
                  *bFound = 1;

                  for(uiPosition=0; uiPosition < (iTermSizes[uiPosTerm]-1); uiPosition++)
                  {
                     if(Term[uiPosTerm][uiPosition] != pBuff[ lOffset+(iPos-iTermSizes[uiPosTerm])+uiPosition+1 ])
                     {
                        *bFound = 0;
                        break;
                     }
                  }

                  if( *bFound )
                  {
                     break;
                  }
               }
            }

            if(*bFound)
            {
               break;
            }
         }

         if( *bFound )
         {
            *plBuffLen = lOffset + iPos - iTermSizes[ uiPosTerm ] + 1;

            pBuff[ *plBuffLen ] = '\0';

            /* Set handle pointer in the end of the line */
            hb_fsSeek( hFileHandle, (((lRead-((LONG)iPos)))*-1)+1, FS_RELATIVE );

            return( pBuff );
         }
      }
      else
      {
         if( !*bFound )
         {
            if( nTries == 0 )
            {
               pBuff[0] = '\0';
               *plBuffLen = 0;
            }
            else
            {
               pBuff[ lOffset + lRead ] = '\0';
               *plBuffLen = lOffset + lRead;
            }

            *bEOF = 1;
         }
      }

      nTries++;
   }
   while ((!*bFound) && lRead > 0 );

   return( pBuff );
}

/* PRG level fReadLine( <Handle>, <@buffer>, [<aTerminators | cTerminator>], [<nReadingBlock>] ) */

HB_FUNC( HB_FREADLINE )
{
   PHB_ITEM pTerm1;
   PHB_ITEM Opt = hb_itemNew( NULL );
   FHANDLE hFileHandle  = (FHANDLE) hb_parnl( 1 );
   char ** Term;
   BYTE * pBuffer;
   int * iTermSizes;
   LONG lSize = hb_parnl(4);
   USHORT i, iTerms;
   BOOL bFound, bEOF;

   if( ( !ISBYREF( 2 ) ) || ( !ISNUM( 1 ) ) )
   {
      hb_errRT_BASE_SubstR( EG_ARG, 3012, NULL, "FREADLINE", 4, hb_paramError(1), hb_paramError(2), hb_paramError(3), hb_paramError(4) );
      return;
   }

   if( ISARRAY( 3 ) || ISCHAR( 3 ) )
   {
      if( ISARRAY( 3 ) )
      {
         pTerm1  = hb_param( 3, HB_IT_ARRAY );
         iTerms = (int) hb_arrayLen(pTerm1);

         if( iTerms <= 0 )
         {
            hb_errRT_BASE_SubstR( EG_ARG, 3012, NULL, "FREADLINE", 4,
               hb_paramError(1), hb_paramError(2),
               hb_paramError(3), hb_paramError(4) );
            return;
         }

         Term   = (char**) hb_xgrab( sizeof(char*) * iTerms );
         iTermSizes = (int *) hb_xgrab( sizeof(int) * iTerms );

         hb_itemClear( Opt );

         for(i=0;i<iTerms;i++)
         {
            hb_arrayGet( pTerm1, i + 1, Opt );
            Term[i]       = (char *) hb_itemGetCPtr(Opt);
            iTermSizes[i] = hb_itemGetCLen(Opt);
         }
      }
      else
      {
         pTerm1        = hb_param( 3, HB_IT_STRING );
         Term          = (char**) hb_xgrab( sizeof(char*) );
         iTermSizes    = (int *) hb_xgrab( sizeof(int) );
         Term[0]       = (char *) hb_itemGetCPtr(pTerm1);
         iTermSizes[0] = hb_itemGetCLen(pTerm1);
         iTerms        = 1;
      }
   }
   else
   {
      Term          = (char**) hb_xgrab( sizeof(char*) );
      iTermSizes    = (int *) hb_xgrab( sizeof(int) );
      Term[0]       = (char *) "\r\n";    /* Should be preplaced with the default EOL sequence */
      iTerms        = 1;
      iTermSizes[0] = 2;
   }

   if( lSize == 0 )
   {
      lSize = READING_BLOCK ;
   }

   pBuffer = hb_fsReadLine( hFileHandle, &lSize, Term, iTermSizes, iTerms, &bFound, &bEOF  );

   if( ! hb_storclen_buffer( (char*) pBuffer, lSize, 2 ) )
      hb_xfree( pBuffer );

   hb_retnl( bEOF ? -1 : 0 );
   hb_xfree( Term );
   hb_xfree( iTermSizes );

   hb_itemRelease( Opt );
}