reportdesign/source/core/misc/conditionalexpression.cxx

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  30
  31 #include "conditionalexpression.hxx"
  32
  33 /** === begin UNO includes === **/
  34 /** === end UNO includes === **/
  35
  36 //........................................................................
  37 namespace rptui
  38 {
  39 //........................................................................
  40
  41     /** === begin UNO using === **/
  42     /** === end UNO using === **/
  43
  44     // =============================================================================
  45     // = ConditionalExpression
  46     // =============================================================================
  47     // -----------------------------------------------------------------------------
  48     ConditionalExpression::ConditionalExpression( const sal_Char* _pAsciiPattern )
  49         :m_sPattern( ::rtl::OUString::createFromAscii( _pAsciiPattern ) )
  50     {
  51     }
  52
  53     // -----------------------------------------------------------------------------
  54     ::rtl::OUString ConditionalExpression::assembleExpression( const ::rtl::OUString& _rFieldDataSource, const ::rtl::OUString& _rLHS, const ::rtl::OUString& _rRHS ) const
  55     {
  56         ::rtl::OUString sExpression( m_sPattern );
  57
  58         sal_Int32 nPatternIndex = sExpression.indexOf( '$' );
  59         while ( nPatternIndex > -1 )
  60         {
  61             const ::rtl::OUString* pReplace = NULL;
  62             switch ( sExpression.getStr()[ nPatternIndex + 1 ] )
  63             {
  64             case '$': pReplace = &_rFieldDataSource; break;
  65             case '1': pReplace = &_rLHS; break;
  66             case '2': pReplace = &_rRHS; break;
  67             default: break;
  68             }
  69
  70             if ( pReplace == NULL )
  71             {
  72                 OSL_ENSURE( false, "ConditionalExpression::assembleExpression: illegal pattern!" );
  73                 break;
  74             }
  75
  76             sExpression = sExpression.replaceAt( nPatternIndex, 2, *pReplace );
  77             nPatternIndex = sExpression.indexOf( '$', nPatternIndex + pReplace->getLength() + 1 );
  78         }
  79         return sExpression;
  80     }
  81
  82     // -----------------------------------------------------------------------------
  83     bool ConditionalExpression::matchExpression( const ::rtl::OUString& _rExpression, const ::rtl::OUString& _rFieldDataSource, ::rtl::OUString& _out_rLHS, ::rtl::OUString& _out_rRHS ) const
  84     {
  85         (void)_rExpression;
  86         (void)_rFieldDataSource;
  87         (void)_out_rLHS;
  88         (void)_out_rRHS;
  89
  90         // if we had regular expression, the matching would be pretty easy ...
  91         // just replace $1 and $2 in the pattern with (.*), and then get them with \1 resp. \2.
  92         // Unfortunately, we don't have such a regexp engine ...
  93
  94         // Okay, let's start with replacing all $$ in our pattern with the actual field data source
  95         ::rtl::OUString sMatchExpression( m_sPattern );
  96         const ::rtl::OUString sFieldDataPattern( RTL_CONSTASCII_USTRINGPARAM( "$$" ) );
  97         sal_Int32 nIndex( sMatchExpression.indexOf( sFieldDataPattern ) );
  98         while ( nIndex != -1 )
  99         {
 100             sMatchExpression = sMatchExpression.replaceAt( nIndex, sFieldDataPattern.getLength(), _rFieldDataSource );
 101             nIndex = sMatchExpression.indexOf( sFieldDataPattern, nIndex + _rFieldDataSource.getLength() );
 102         }
 103
 104         const ::rtl::OUString sLHSPattern( RTL_CONSTASCII_USTRINGPARAM( "$1" ) );
 105         const ::rtl::OUString sRHSPattern( RTL_CONSTASCII_USTRINGPARAM( "$2" ) );
 106         sal_Int32 nLHSIndex( sMatchExpression.indexOf( sLHSPattern ) );
 107         sal_Int32 nRHSIndex( sMatchExpression.indexOf( sRHSPattern ) );
 108
 109         // now we should have at most one occurance of $1 and $2, resp.
 110         OSL_ENSURE( sMatchExpression.indexOf( sLHSPattern, nLHSIndex + 1 ) == -1,
 111             "ConditionalExpression::matchExpression: unsupported pattern (more than one LHS occurance)!" );
 112         OSL_ENSURE( sMatchExpression.indexOf( sRHSPattern, nRHSIndex + 1 ) == -1,
 113             "ConditionalExpression::matchExpression: unsupported pattern (more than one RHS occurance)!" );
 114         // Also, an LHS must be present, and precede the RHS (if present)
 115         OSL_ENSURE( ( nLHSIndex != -1 ) && ( ( nLHSIndex < nRHSIndex ) || ( nRHSIndex == -1 ) ),
 116             "ConditionalExpression::matchExpression: no LHS, or an RHS preceeding the LHS - this is not supported!" );
 117
 118         // up to the occurance of the LHS (which must exist, see above), the two expressions
 119         // must be identical
 120         if ( _rExpression.getLength() < nLHSIndex )
 121             return false;
 122         const ::rtl::OUString sExprPart1( _rExpression.copy( 0, nLHSIndex ) );
 123         const ::rtl::OUString sMatchExprPart1( sMatchExpression.copy( 0, nLHSIndex ) );
 124         if ( sExprPart1 != sMatchExprPart1 )
 125             // the left-most expression parts do not match
 126             return false;
 127
 128         // after the occurance of the RHS (or the LHS, if there is no RHS), the two expressions
 129         // must be identical, too
 130         bool bHaveRHS( nRHSIndex != -1 );
 131         sal_Int32 nRightMostIndex( bHaveRHS ? nRHSIndex : nLHSIndex );
 132         const ::rtl::OUString sMatchExprPart3( sMatchExpression.copy( nRightMostIndex + 2 ) );
 133         if ( _rExpression.getLength() < sMatchExprPart3.getLength() )
 134             // the expression is not even long enough to hold the right-most part of the match expression
 135             return false;
 136         const ::rtl::OUString sExprPart3( _rExpression.copy( _rExpression.getLength() - sMatchExprPart3.getLength() ) );
 137         if ( sExprPart3 != sMatchExprPart3 )
 138             // the right-most expression parts do not match
 139             return false;
 140
 141         // if we don't have an RHS, we're done
 142         if ( !bHaveRHS )
 143         {
 144             _out_rLHS = _rExpression.copy( sExprPart1.getLength(), _rExpression.getLength() - sExprPart1.getLength() - sExprPart3.getLength() );
 145             return true;
 146         }
 147
 148         // strip the match expression by its right-most and left-most part, and by the placeholders $1 and $2
 149         sal_Int32 nMatchExprPart2Start( nLHSIndex + sLHSPattern.getLength() );
 150         ::rtl::OUString sMatchExprPart2 = sMatchExpression.copy(
 151             nMatchExprPart2Start,
 152             sMatchExpression.getLength() - nMatchExprPart2Start - sMatchExprPart3.getLength() - 2
 153         );
 154         // strip the expression by its left-most and right-most part
 155         const ::rtl::OUString sExpression( _rExpression.copy(
 156             sExprPart1.getLength(),
 157             _rExpression.getLength() - sExprPart1.getLength() - sExprPart3.getLength()
 158         ) );
 159
 160         sal_Int32 nPart2Index = sExpression.indexOf( sMatchExprPart2 );
 161         if ( nPart2Index == -1 )
 162             // the "middle" part of the match expression does not exist in the expression at all
 163             return false;
 164
 165         OSL_ENSURE( sExpression.indexOf( sMatchExprPart2, nPart2Index + 1 ) == -1,
 166             "ConditionalExpression::matchExpression: ambiguous matching!" );
 167             // if this fires, then we're lost: The middle part exists two times in the expression,
 168             // so we cannot reliably determine what's the LHS and what's the RHS.
 169             // Well, the whole mechanism is flawed, anyway:
 170             // Encoding the field content in the conditional expression will break as soon
 171             // as somebody
 172             // - assigns a Data Field to a control
 173             // - creates a conditional format expression for the control
 174             // - assigns another Data Field to the control
 175             // - opens the Conditional Format Dialog, again
 176             // Here, at the latest, you can see that we need another mechanism, anyway, which does not
 177             // rely on those strange expression building/matching
 178
 179         _out_rLHS = sExpression.copy( 0, nPart2Index );
 180         _out_rRHS = sExpression.copy( nPart2Index + sMatchExprPart2.getLength() );
 181
 182         return true;
 183     }
 184
 185     // =============================================================================
 186     // = ConditionalExpressionFactory
 187     // =============================================================================
 188     // -----------------------------------------------------------------------------
 189     size_t ConditionalExpressionFactory::getKnownConditionalExpressions( ConditionalExpressions& _out_rCondExp )
 190     {
 191         ConditionalExpressions aEmpty;
 192         _out_rCondExp.swap( aEmpty );
 193
 194         _out_rCondExp[ eBetween ]        = PConditionalExpression( new ConditionalExpression( "AND( ( $$ ) >= ( $1 ); ( $$ ) <= ( $2 ) )" ) );
 195         _out_rCondExp[ eNotBetween ]     = PConditionalExpression( new ConditionalExpression( "NOT( AND( ( $$ ) >= ( $1 ); ( $$ ) <= ( $2 ) ) )" ) );
 196         _out_rCondExp[ eEqualTo ]        = PConditionalExpression( new ConditionalExpression( "( $$ ) = ( $1 )" ) );
 197         _out_rCondExp[ eNotEqualTo ]     = PConditionalExpression( new ConditionalExpression( "( $$ ) <> ( $1 )" ) );
 198         _out_rCondExp[ eGreaterThan ]    = PConditionalExpression( new ConditionalExpression( "( $$ ) > ( $1 )" ) );
 199         _out_rCondExp[ eLessThan ]       = PConditionalExpression( new ConditionalExpression( "( $$ ) < ( $1 )" ) );
 200         _out_rCondExp[ eGreaterOrEqual ] = PConditionalExpression( new ConditionalExpression( "( $$ ) >= ( $1 )" ) );
 201         _out_rCondExp[ eLessOrEqual ]    = PConditionalExpression( new ConditionalExpression( "( $$ ) <= ( $1 )" ) );
 202
 203         return _out_rCondExp.size();
 204     }
 205 //........................................................................
 206 } // namespace rptui
 207 //........................................................................