harbour-core/harbour/source/rdd/dbtotal.prg

/*
 * $Id$
 */

/*
 * Harbour Project source code:
 * __DBTOTAL FUNCTION
 *
 * Copyright 2000 Luiz Rafael Culik <culik@sl.conex.net>
 * 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, 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 "set.ch"
#include "error.ch"

FUNCTION __DBTOTAL( cFile, xKey, aFields, ;
                        xFor, xWhile, nNext, nRec, lRest, rdd, ;
                        nConnection, cdpId)

    LOCAL CurSelect
    LOCAL NewSelect
    LOCAL aNewDbStruct
    LOCAL aGetField
    LOCAL aFieldsSum
    LOCAL lDbTransRecord
    LOCAL xCurKey
    LOCAL bKeyBlock
    LOCAL bForBlock
    LOCAL bWhileBlock
    LOCAL cset
    LOCAL flag_err
    LOCAL err_block
    LOCAL wRec
    LOCAL err

    err_block := Errorblock( { | x | Break( x ) } )
    flag_err  := .F.
    cset      := Set( _SET_CANCEL, .f. )


    IF ( Valtype( xWhile ) == "C" )
        bWhileBlock := "{||" + xWhile + "}"
        bWhileBlock := &bWhileBlock
    ELSE
        IF ( Valtype( xWhile ) != "B" )
            bWhileBlock := { || .t. }
        ELSE
            bWhileBlock := xWhile
            lRest    := .T.
        ENDIF

    ENDIF

    IF ( Valtype( xFor ) == "C" )
        bForBlock := "{||" + xFor + "}"
        bForBlock := &xFor
    ELSE
        IF ( Valtype( xFor ) != "B" )
            bForBlock := { || .t. }
        ELSE
            bForBlock := xFor
        ENDIF

    ENDIF

    Iif( lRest == NIL, .F., lRest )

    IF ( nRec != NIL )
        GOTO nRec
        nNext := 1
    ELSE
        IF ( nNext == NIL )
            nNext := - 1
        ELSE
            lRest := .T.
        ENDIF

        IF ( !lRest )
            GOTO TOP
        ENDIF

    ENDIF

    CurSelect    := SELECT()
    aNewDbStruct := {}
    Aeval( Dbstruct(), { | _1 | Iif( _1[ 2 ] == "M", NIL, Aadd( aNewDbStruct, _1 ) ) } )
    IF ( Empty( aNewDbStruct ) )
        RETURN ( .F. )
    ENDIF

    BEGIN SEQUENCE

        IF ( Empty( xKey ) )
            xKey := Indexkey()
        ENDIF

        IF ( Empty( xKey ) )
            Set( _SET_CANCEL, cset )
            err             := errorNew()
            err:description := "invalid argument"
            err:genCode     := EG_ARG
            Eval( Errorblock(), err )
        ENDIF

        IF ( Valtype( xKey ) == "C" )
            bKeyBlock := "{||" + xKey + "}"
            bKeyBlock := &bKeyBlock
        ELSE
            IF ( Valtype( xKey ) != "B" )
                bKeyBlock := { || .t. }
            ELSE
                bKeyBlock := xKey
            ENDIF

        ENDIF

        aGetField := {}
        Aeval( aFields, { | _1 | Aadd( aGetField, getfield( _1 ) ) } )
        aFieldsSum := Array( Len( aGetField ) )

        dbCreate( cFile, aNewDbStruct, rdd, .T., "", cdpId, nConnection )
        NewSelect := SELECT()
        SELECT( CurSelect )

        WHILE ( !Eof() .and. nNext != 0 .and. Eval( bWhileBlock ) )
            lDbTransRecord := .F.
            Afill( aFieldsSum, 0 )
            xCurKey := Eval( bKeyBlock )
            WHILE ( !Eof() .and. nNext -- != 0 .and. Eval( bWhileBlock ) .and. ;
                   xCurKey == Eval( bKeyBlock ) ;
                   )
                IF ( Eval( bForBlock ) )
                    IF ( !lDbTransRecord )

                        wRec := dbRead()
                        SELECT( NewSelect )
                        Dbappend()
                        dbwrite( wRec )

                        SELECT( CurSelect )

                        lDbTransRecord := .T.
                    ENDIF

                    Aeval( aGetField, { | _1, _2 | aFieldsSum[ _2 ] := aFieldsSum[ _2 ] + ;
                                        Eval( _1 ) ;
                                        } ;
                                        )
                ENDIF

                SKIP
            ENDDO

            IF ( lDbTransRecord )
                SELECT( NewSelect )
                Aeval( aGetField, { | _1, _2 | Eval( _1, aFieldsSum[ _2 ] ) } )
                SELECT( CurSelect )
            ENDIF

        ENDDO

    RECOVER USING err
        flag_err := .t.

    ENDSEQUENCE

    IF ( NewSelect != NIL )
        SELECT( NewSelect )
        CLOSE
    ENDIF

    SELECT( CurSelect )
    Set( _SET_CANCEL, cset )
    Errorblock( err_block )
    IF ( flag_err )
        err:operation += "/__DBTOTAL"
        Eval( Errorblock(), err )

    ENDIF

RETURN ( .t. )

STATIC FUNCTION GETFIELD( cField )

    LOCAL nPos
    LOCAL SelectFromField
    LOCAL CurSelect
    LOCAL err
    LOCAL lErr
    CurSelect := SELECT()

    IF ( ( nPos := At( "->", cField ) ) > 0 )
        SelectFromField := Left( cField, nPos - 1 )
        IF ( Select( SelectFromField ) != CurSelect )
            err           := ErrorNew()
            err:severity  := ES_ERROR
            err:gencode   := EG_SYNTAX
            err:subsystem := "DBCMD"
            err:candefaul := .T.
            err:operation := cField
            err:subcode   := 1101
            lErr        := Eval( Errorblock(), err )
            IF ( Valtype( lErr ) != "L" .or. lErr )
            ENDIF

            BREAK( err )
        ENDIF

        cField := Substr( cField, nPos + 2 )
    ENDIF

RETURN ( Fieldblock( cField ) )

STATIC FUNCTION DbWrite( w )

    LOCAL ncount

    FOR ncount := 1 TO Len( w )
        Fieldput( ncount, w[ ncount ] )
    NEXT

RETURN nil

STATIC FUNCTION DbRead()

    LOCAL aRec   := {}
    LOCAL nCount

    FOR nCount := 1 TO FCount()
        IF ( FieldType( nCount ) != "M" )
            AAdd( aRec, Fieldget( nCount ) )
        ENDIF
    NEXT

RETURN aRec