SemanticMediaWiki/includes/storage/SMW_Description.php

Go to the documentation of this file.

<?php
abstract class SMWDescription {

        protected $m_printreqs = array();

        public function getPrintRequests() {
                return $this->m_printreqs;
        }

        public function setPrintRequests( array $printrequests ) {
                $this->m_printreqs = $printrequests;
        }

        public function addPrintRequest( SMWPrintRequest $printrequest ) {
                $this->m_printreqs[] = $printrequest;
        }

        public function prependPrintRequest( SMWPrintRequest $printrequest ) {
                array_unshift( $this->m_printreqs, $printrequest );
        }

        abstract public function getQueryString( $asvalue = false );

        abstract public function isSingleton();

        public function getSize() {
                return 1;
        }

        public function getDepth() {
                return 0;
        }

        public function getQueryFeatures() {
                return 0;
        }

        public function prune( &$maxsize, &$maxdepth, &$log ) {
                if ( ( $maxsize < $this->getSize() ) || ( $maxdepth < $this->getDepth() ) ) {
                        $log[] = $this->getQueryString();
                        
                        $result = new SMWThingDescription();
                        $result->setPrintRequests( $this->getPrintRequests() );
                        
                        return $result;
                } else {
                        $maxsize = $maxsize - $this->getSize();
                        $maxdepth = $maxdepth - $this->getDepth();
                        
                        return $this;
                }
        }
        
}

class SMWThingDescription extends SMWDescription {

        public function getQueryString( $asvalue = false ) {
                return $asvalue ? '+' : '';
        }

        public function isSingleton() {
                return false;
        }

        public function getSize() {
                return 0; // no real condition, no size or depth
        }

        public function prune( &$maxsize, &$maxdepth, &$log ) {
                return $this;
        }

}

class SMWClassDescription extends SMWDescription {
        
        protected $m_diWikiPages;

        public function __construct( $content ) {
                if ( $content instanceof SMWDIWikiPage ) {
                        $this->m_diWikiPages = array( $content );
                } elseif ( is_array( $content ) ) {
                        $this->m_diWikiPages = $content;
                } else {
                        throw new Exception( "SMWClassDescription::__construct(): parameter must be an SMWDIWikiPage object or an array of such objects." );
                }
        }

        public function addDescription( SMWClassDescription $description ) {
                $this->m_diWikiPages = array_merge( $this->m_diWikiPages, $description->getCategories() );
        }

        public function getCategories() {
                return $this->m_diWikiPages;
        }

        public function getQueryString( $asvalue = false ) {
                $first = true;
                foreach ( $this->m_diWikiPages as $wikiPage ) {
                        $wikiValue = SMWDataValueFactory::newDataItemValue( $wikiPage, null );
                        if ( $first ) {
                                $result = '[[' . $wikiValue->getPrefixedText();
                                $first = false;
                        } else {
                                $result .= '||' . $wikiValue->getText();
                        }
                }
                
                $result .= ']]';
                
                if ( $asvalue ) {
                        return ' &lt;q&gt;' . $result . '&lt;/q&gt; ';
                } else {
                        return $result;
                }
        }

        public function isSingleton() {
                return false;
        }

        public function getSize() {
                global $smwgQSubcategoryDepth;
                if ( $smwgQSubcategoryDepth > 0 ) {
                        return 1; // disj. of cats should not cause much effort if we compute cat-hierarchies anyway!
                } else {
                        return count( $this->m_diWikiPages );
                }
        }

        public function getQueryFeatures() {
                if ( count( $this->m_diWikiPages ) > 1 ) {
                        return SMW_CATEGORY_QUERY | SMW_DISJUNCTION_QUERY;
                } else {
                        return SMW_CATEGORY_QUERY;
                }
        }

        public function prune( &$maxsize, &$maxdepth, &$log ) {
                if ( $maxsize >= $this->getSize() ) {
                        $maxsize = $maxsize - $this->getSize();
                        return $this;
                } elseif ( $maxsize <= 0 ) {
                        $log[] = $this->getQueryString();
                        $result = new SMWThingDescription();
                } else {
                        $result = new SMWClassDescription( array_slice( $this->m_diWikiPages, 0, $maxsize ) );
                        $rest = new SMWClassDescription( array_slice( $this->m_diWikiPages, $maxsize ) );
                        
                        $log[] = $rest->getQueryString();
                        $maxsize = 0;
                }
                
                $result->setPrintRequests( $this->getPrintRequests() );
                return $result;
        }

}


class SMWConceptDescription extends SMWDescription {
        
        protected $m_concept;

        public function __construct( SMWDIWikiPage $concept ) {
                $this->m_concept = $concept;
        }

        public function getConcept() {
                return $this->m_concept;
        }

        public function getQueryString( $asvalue = false ) {
                $pageValue = SMWDataValueFactory::newDataItemValue( $this->m_concept, null );
                $result = '[[' . $pageValue->getPrefixedText() . ']]';
                if ( $asvalue ) {
                        return ' &lt;q&gt;' . $result . '&lt;/q&gt; ';
                } else {
                        return $result;
                }
        }

        public function isSingleton() {
                return false;
        }

        public function getQueryFeatures() {
                return SMW_CONCEPT_QUERY;
        }

}


class SMWNamespaceDescription extends SMWDescription {
        
        protected $m_namespace;

        public function __construct( $namespace ) {
                $this->m_namespace = $namespace;
        }

        public function getNamespace() {
                return $this->m_namespace;
        }

        public function getQueryString( $asvalue = false ) {
                global $wgContLang;
                if ( $asvalue ) {
                        return ' &lt;q&gt;[[' . $wgContLang->getNSText( $this->m_namespace ) . ':+]]&lt;/q&gt; ';
                } else {
                        return '[[' . $wgContLang->getNSText( $this->m_namespace ) . ':+]]';
                }
        }

        public function isSingleton() {
                return false;
        }

        public function getQueryFeatures() {
                return SMW_NAMESPACE_QUERY;
        }

}

class SMWValueDescription extends SMWDescription {
        
        protected $m_dataItem;
        protected $m_comparator;
        protected $m_property;

        public function __construct( SMWDataItem $dataItem, $property, $comparator = SMW_CMP_EQ ) {
                $this->m_dataItem = $dataItem;
                $this->m_comparator = $comparator;
                $this->m_property = $property;
        }

        public function getDataValue() {
                return $this->m_dataItem;
        }

        public function getDataItem() {
                return $this->m_dataItem;
        }

        public function getComparator() {
                return $this->m_comparator;
        }

        public function getQueryString( $asvalue = false ) {
                $comparator = SMWQueryLanguage::getStringForComparator( $this->m_comparator );
                $dataValue = SMWDataValueFactory::newDataItemValue( $this->m_dataItem, $this->m_property );
                if ( $asvalue ) {
                        return $comparator . $dataValue->getWikiValue();
                } else { // this only is possible for values of Type:Page
                        if ( $comparator === '' ) { // some extra care for Category: pages
                                return '[[:' . $dataValue->getWikiValue() . ']]';
                        } else {
                                return '[[' . $comparator . $dataValue->getWikiValue() . ']]';
                        }
                }
        }

        public function isSingleton() {
                if ( $this->m_comparator == SMW_CMP_EQ ) {
                        return true;
                } else {
                        return false;
                }
        }

        public function getSize() {
                return 1;
        }

}


class SMWConjunction extends SMWDescription {
        
        protected $m_descriptions;

        public function __construct( $descriptions = array() ) {
                $this->m_descriptions = $descriptions;
        }

        public function getDescriptions() {
                return $this->m_descriptions;
        }

        public function addDescription( SMWDescription $description ) {
                if ( ! ( $description instanceof SMWThingDescription ) ) {
                        if ( $description instanceof SMWConjunction ) { // absorb sub-conjunctions
                                foreach ( $description->getDescriptions() as $subdesc ) {
                                        $this->m_descriptions[] = $subdesc;
                                }
                        } else {
                                $this->m_descriptions[] = $description;
                        }
                        
                        // move print descriptions downwards
                        $this->m_printreqs = array_merge( $this->m_printreqs, $description->getPrintRequests() );
                        $description->setPrintRequests( array() );
                }
        }

        public function getQueryString( $asvalue = false ) {
                $result = '';
                
                foreach ( $this->m_descriptions as $desc ) {
                        $result .= ( $result ? ' ' : '' ) . $desc->getQueryString( false );
                }
                
                if ( $result === '' ) {
                        return $asvalue ? '+' : '';
                } else { // <q> not needed for stand-alone conjunctions (AND binds stronger than OR)
                        return $asvalue ? " &lt;q&gt;{$result}&lt;/q&gt; " : $result;
                }
        }

        public function isSingleton() {
                foreach ( $this->m_descriptions as $d ) {
                        if ( $d->isSingleton() ) {
                                return true;
                        }
                }
                return false;
        }

        public function getSize() {
                $size = 0;

                foreach ( $this->m_descriptions as $desc ) {
                        $size += $desc->getSize();
                }

                return $size;
        }

        public function getDepth() {
                $depth = 0;

                foreach ( $this->m_descriptions as $desc ) {
                        $depth = max( $depth, $desc->getDepth() );
                }

                return $depth;
        }

        public function getQueryFeatures() {
                $result = SMW_CONJUNCTION_QUERY;

                foreach ( $this->m_descriptions as $desc ) {
                        $result = $result | $desc->getQueryFeatures();
                }

                return $result;
        }

        public function prune( &$maxsize, &$maxdepth, &$log ) {
                if ( $maxsize <= 0 ) {
                        $log[] = $this->getQueryString();
                        return new SMWThingDescription();
                }
                
                $prunelog = array();
                $newdepth = $maxdepth;
                $result = new SMWConjunction();
                
                foreach ( $this->m_descriptions as $desc ) {
                        $restdepth = $maxdepth;
                        $result->addDescription( $desc->prune( $maxsize, $restdepth, $prunelog ) );
                        $newdepth = min( $newdepth, $restdepth );
                }
                
                if ( count( $result->getDescriptions() ) > 0 ) {
                        $log = array_merge( $log, $prunelog );
                        $maxdepth = $newdepth;
                        
                        if ( count( $result->getDescriptions() ) == 1 ) { // simplify unary conjunctions!
                                $descriptions = $result->getDescriptions();
                                $result = array_shift( $descriptions );
                        }
                        
                        $result->setPrintRequests( $this->getPrintRequests() );
                        
                        return $result;
                } else {
                        $log[] = $this->getQueryString();
                        
                        $result = new SMWThingDescription();
                        $result->setPrintRequests( $this->getPrintRequests() );
                        
                        return $result;
                }
        }
        
}

class SMWDisjunction extends SMWDescription {
        protected $m_descriptions;
        protected $m_classdesc = null; // contains a single class description if any such disjunct was given;
                                       // disjunctive classes are aggregated therein
        protected $m_true = false; // used if disjunction is trivially true already

        public function __construct( $descriptions = array() ) {
                foreach ( $descriptions as $desc ) {
                        $this->addDescription( $desc );
                }
        }

        public function getDescriptions() {
                return $this->m_descriptions;
        }

        public function addDescription( SMWDescription $description ) {
                if ( $description instanceof SMWThingDescription ) {
                        $this->m_true = true;
                        $this->m_descriptions = array(); // no conditions any more
                        $this->m_classdesc = null;
                }
                
                if ( !$this->m_true ) {
                        if ( $description instanceof SMWClassDescription ) { // combine class descriptions
                                if ( is_null( $this->m_classdesc ) ) { // first class description
                                        $this->m_classdesc = $description;
                                        $this->m_descriptions[] = $description;
                                } else {
                                        $this->m_classdesc->addDescription( $description );
                                }
                        } elseif ( $description instanceof SMWDisjunction ) { // absorb sub-disjunctions
                                foreach ( $description->getDescriptions() as $subdesc ) {
                                        $this->m_descriptions[] = $subdesc;
                                }
                        // } elseif ($description instanceof SMWSomeProperty) {
                        } else {
                                $this->m_descriptions[] = $description;
                        }
                }
                
                // move print descriptions downwards
                $this->m_printreqs = array_merge( $this->m_printreqs, $description->getPrintRequests() );
                $description->setPrintRequests( array() );
        }

        public function getQueryString( $asvalue = false ) {
                if ( $this->m_true ) {
                        return '+';
                }
                
                $result = '';
                $sep = $asvalue ? '||':' OR ';
                
                foreach ( $this->m_descriptions as $desc ) {
                        $subdesc = $desc->getQueryString( $asvalue );
                        
                        if ( $desc instanceof SMWSomeProperty ) { // enclose in <q> for parsing
                                if ( $asvalue ) {
                                        $subdesc = ' &lt;q&gt;[[' . $subdesc . ']]&lt;/q&gt; ';
                                } else {
                                        $subdesc = ' &lt;q&gt;' . $subdesc . '&lt;/q&gt; ';
                                }
                        }
                        
                        $result .= ( $result ? $sep:'' ) . $subdesc;
                }
                if ( $asvalue ) {
                        return $result;
                } else {
                        return ' &lt;q&gt;' . $result . '&lt;/q&gt; ';
                }
        }

        public function isSingleton() {
                if ( count( $this->m_descriptions ) != 1 ) {
                        return false;
                } else {
                        return $this->m_descriptions[0]->isSingleton();
                }
        }

        public function getSize() {
                $size = 0;

                foreach ( $this->m_descriptions as $desc ) {
                        $size += $desc->getSize();
                }

                return $size;
        }

        public function getDepth() {
                $depth = 0;

                foreach ( $this->m_descriptions as $desc ) {
                        $depth = max( $depth, $desc->getDepth() );
                }

                return $depth;
        }

        public function getQueryFeatures() {
                $result = SMW_DISJUNCTION_QUERY;

                foreach ( $this->m_descriptions as $desc ) {
                        $result = $result | $desc->getQueryFeatures();
                }

                return $result;
        }

        public function prune( &$maxsize, &$maxdepth, &$log ) {
                if ( $maxsize <= 0 ) {
                        $log[] = $this->getQueryString();
                        return new SMWThingDescription();
                }

                $prunelog = array();
                $newdepth = $maxdepth;
                $result = new SMWDisjunction();

                foreach ( $this->m_descriptions as $desc ) {
                        $restdepth = $maxdepth;
                        $result->addDescription( $desc->prune( $maxsize, $restdepth, $prunelog ) );
                        $newdepth = min( $newdepth, $restdepth );
                }

                if ( count( $result->getDescriptions() ) > 0 ) {
                        $log = array_merge( $log, $prunelog );
                        $maxdepth = $newdepth;
                        
                        if ( count( $result->getDescriptions() ) == 1 ) { // simplify unary disjunctions!
                                $descriptions = $result->getDescriptions();
                                $result = array_shift( $descriptions );
                        }

                        $result->setPrintRequests( $this->getPrintRequests() );

                        return $result;
                } else {
                        $log[] = $this->getQueryString();

                        $result = new SMWThingDescription();
                        $result->setPrintRequests( $this->getPrintRequests() );

                        return $result;
                }
        }
}

class SMWSomeProperty extends SMWDescription {

        protected $m_description;
        protected $m_property;

        public function __construct( SMWDIProperty $property, SMWDescription $description ) {
                $this->m_property = $property;
                $this->m_description = $description;
        }

        public function getProperty() {
                return $this->m_property;
        }

        public function getDescription() {
                return $this->m_description;
        }

        public function getQueryString( $asvalue = false ) {
                $subdesc = $this->m_description;
                $propertyChainString = $this->m_property->getLabel();
                $propertyname = $propertyChainString;

                while ( ( $propertyname !== '' ) && ( $subdesc instanceof SMWSomeProperty ) ) { // try to use property chain syntax
                        $propertyname = $subdesc->getProperty()->getLabel();
                        if ( $propertyname !== '' ) {
                                $propertyChainString .= '.' . $propertyname;
                                $subdesc = $subdesc->getDescription();
                        }
                }

                if ( $asvalue ) {
                        return '&lt;q&gt;[[' . $propertyChainString . '::' . $subdesc->getQueryString( true ) . ']]&lt;/q&gt;';
                } else {
                        return '[[' . $propertyChainString . '::' . $subdesc->getQueryString( true ) . ']]';
                }
        }

        public function isSingleton() {
                return false;
        }

        public function getSize() {
                return 1 + $this->getDescription()->getSize();
        }

        public function getDepth() {
                return 1 + $this->getDescription()->getDepth();
        }

        public function getQueryFeatures() {
                return SMW_PROPERTY_QUERY | $this->m_description->getQueryFeatures();
        }

        public function prune( &$maxsize, &$maxdepth, &$log ) {
                if ( ( $maxsize <= 0 ) || ( $maxdepth <= 0 ) ) {
                        $log[] = $this->getQueryString();
                        return new SMWThingDescription();
                }

                $maxsize--;
                $maxdepth--;

                $result = new SMWSomeProperty( $this->m_property, $this->m_description->prune( $maxsize, $maxdepth, $log ) );
                $result->setPrintRequests( $this->getPrintRequests() );

                return $result;
        }
        
}

---