1 files changed, 304 insertions, 0 deletions
diff --git a/www/wiki/extensions/SemanticMediaWiki/src/SQLStore/RequestOptionsProc.php b/www/wiki/extensions/SemanticMediaWiki/src/SQLStore/RequestOptionsProc.php
new file mode 100644
index 00000000..8a8cc949
--- /dev/null
+++ b/www/wiki/extensions/SemanticMediaWiki/src/SQLStore/RequestOptionsProc.php
@@ -0,0 +1,304 @@
+<?php
+
+namespace SMW\SQLStore;
+
+use SMW\DIWikiPage;
+use SMW\Store;
+use SMWDIBlob as DIBlob;
+use SMWRequestOptions as RequestOptions;
+use SMWStringCondition as StringCondition;
+
+/**
+ * @license GNU GPL v2+
+ * @since 2.3
+ *
+ * @author Markus Krötzsch
+ * @author mwjames
+ */
+class RequestOptionsProc {
+
+	/**
+	 * Transform input parameters into a suitable array of SQL options.
+	 * The parameter $valuecol defines the string name of the column to which
+	 * sorting requests etc. are to be applied.
+	 *
+	 * @since 1.8
+	 *
+	 * @param RequestOptions|null $requestOptions
+	 * @param string $valueCol
+	 *
+	 * @return array
+	 */
+	public static function getSQLOptions( RequestOptions $requestOptions = null, $valueCol = '' ) {
+		$sqlConds = [];
+
+		if ( $requestOptions === null ) {
+			return $sqlConds;
+		}
+
+		if ( $requestOptions->getLimit() > 0 ) {
+			$sqlConds['LIMIT'] = $requestOptions->getLimit();
+		}
+
+		if ( $requestOptions->getOffset() > 0 ) {
+			$sqlConds['OFFSET'] = $requestOptions->getOffset();
+		}
+
+		if ( ( $valueCol !== '' ) && ( $requestOptions->sort ) ) {
+			$sqlConds['ORDER BY'] = $requestOptions->ascending ? $valueCol : $valueCol . ' DESC';
+		}
+
+		if ( $requestOptions->getOption( 'GROUP BY' ) ) {
+			$sqlConds['GROUP BY'] = $requestOptions->getOption( 'GROUP BY' );
+		}
+
+		if ( $requestOptions->getOption( 'DISTINCT' ) ) {
+			$sqlConds['DISTINCT'] = $requestOptions->getOption( 'DISTINCT' );
+		}
+
+		// Avoid a possible filesort (likely caused by ORDER BY) when limit is
+		// less than 2
+		if ( $requestOptions->limit < 2 || $requestOptions->getOption( 'ORDER BY' ) === false ) {
+			unset( $sqlConds['ORDER BY'] );
+		}
+
+		return $sqlConds;
+	}
+
+	/**
+	 * Transform input parameters into a suitable string of additional SQL
+	 * conditions. The parameter $valuecol defines the string name of the
+	 * column to which value restrictions etc. are to be applied.
+	 *
+	 * @since 1.8
+	 *
+	 * @param Store $store
+	 * @param RequestOptions|null $requestOptions
+	 * @param string $valueCol name of SQL column to which conditions apply
+	 * @param string $labelCol name of SQL column to which string conditions apply, if any
+	 * @param boolean $addAnd indicate whether the string should begin with " AND " if non-empty
+	 *
+	 * @return string
+	 */
+	public static function getSQLConditions( Store $store, RequestOptions $requestOptions = null, $valueCol = '', $labelCol = '', $addAnd = true ) {
+		$sqlConds = '';
+
+		if ( $requestOptions === null ) {
+			return $sqlConds;
+		}
+
+		$connection = $store->getConnection( 'mw.db' );
+
+		// Apply value boundary
+		if ( ( $valueCol !== '' ) && ( $requestOptions->boundary !== null ) ) {
+
+			if ( $requestOptions->ascending ) {
+				$op = $requestOptions->include_boundary ? ' >= ' : ' > ';
+			} else {
+				$op = $requestOptions->include_boundary ? ' <= ' : ' < ';
+			}
+
+			$sqlConds .= ( $addAnd ? ' AND ' : '' ) . $valueCol . $op . $connection->addQuotes( $requestOptions->boundary );
+		}
+
+		// Apply string conditions
+		if ( $labelCol !== '' ) {
+			foreach ( $requestOptions->getStringConditions() as $strcond ) {
+				$string = str_replace( '_', '\_', $strcond->string );
+				$condition = 'LIKE';
+
+				switch ( $strcond->condition ) {
+					case StringCondition::COND_PRE:
+						$string .= '%';
+					break;
+					case StringCondition::COND_POST:
+						$string = '%' . $string;
+					break;
+					case StringCondition::COND_MID:
+						$string = '%' . $string . '%';
+					break;
+					case StringCondition::COND_EQ:
+						$string = $strcond->string;
+						$condition = '=';
+					break;
+				}
+
+				$conditionOperator = $strcond->isOr ? ' OR ' : ' AND ';
+
+				if ( $strcond->isNot ) {
+					$sqlConds = " ($sqlConds) AND ($labelCol NOT $condition ". $connection->addQuotes( $string ) . ") ";
+				} else {
+					$sqlConds .= ( ( $addAnd || ( $sqlConds !== '' ) ) ? $conditionOperator : '' ) . "$labelCol $condition " . $connection->addQuotes( $string );
+				}
+			}
+		}
+
+		foreach ( $requestOptions->getExtraConditions() as $extraCondition ) {
+
+			$expr = $addAnd ? 'AND' : '';
+
+			if ( is_array( $extraCondition ) ) {
+				foreach ( $extraCondition as $k => $v ) {
+					$expr = $k;
+					$extraCondition = $v;
+				}
+			}
+
+			$sqlConds .= ( ( $addAnd || ( $sqlConds !== '' ) ) ? " $expr " : '' ) . $extraCondition;
+		}
+
+		return $sqlConds;
+	}
+
+	/**
+	 * Not in all cases can requestoptions be forwarded to the DB using
+	 * getSQLConditions() and getSQLOptions(): some data comes from caches
+	 * that do not respect the options yet. This method takes an array of
+	 * results (SMWDataItem objects) *of the same type* and applies the
+	 * given requestoptions as appropriate.
+	 *
+	 * @since 1.8
+	 *
+	 * @param Store $store
+	 * @param array $data array of SMWDataItem objects
+	 * @param SMWRequestOptions|null $requestoptions
+	 *
+	 * @return SMWDataItem[]
+	 */
+	public static function applyRequestOptions( Store $store, array $data, RequestOptions $requestOptions = null ) {
+
+		if ( $data === [] || $requestOptions === null ) {
+			return $data;
+		}
+
+		$result = [];
+		$sortres = [];
+
+		$sampleDataItem = reset( $data );
+		$isNumeric = is_numeric( $sampleDataItem->getSortKey() );
+
+		$i = 0;
+
+		foreach ( $data as $item ) {
+
+			list( $label, $value ) = self::getSortKeyForItem( $store, $item );
+
+			$keepDataValue = self::applyBoundaryConditions( $requestOptions, $value, $isNumeric );
+			$keepDataValue = self::applyStringConditions( $requestOptions, $label, $keepDataValue );
+
+			if ( $keepDataValue ) {
+				$result[$i] = $item;
+				$sortres[$i] = $value;
+				$i++;
+			}
+		}
+
+		self::applySortRestriction( $requestOptions, $result, $sortres, $isNumeric );
+		self::applyLimitRestriction( $requestOptions, $result );
+
+		return $result;
+	}
+
+	private static function applyStringConditions( $requestOptions, $label, $keepDataValue ) {
+
+		foreach ( $requestOptions->getStringConditions() as $strcond ) { // apply string conditions
+			switch ( $strcond->condition ) {
+				case StringCondition::STRCOND_PRE:
+					$keepDataValue = $keepDataValue && ( strpos( $label, $strcond->string ) === 0 );
+					break;
+				case StringCondition::STRCOND_POST:
+					$keepDataValue = $keepDataValue && ( strpos( strrev( $label ), strrev( $strcond->string ) ) === 0 );
+					break;
+				case StringCondition::STRCOND_MID:
+					$keepDataValue = $keepDataValue && ( strpos( $label, $strcond->string ) !== false );
+					break;
+			}
+		}
+
+		return $keepDataValue;
+	}
+
+	private static function applyBoundaryConditions( $requestOptions, $value, $isNumeric ) {
+		$keepDataValue = true; // keep datavalue only if this remains true
+
+		if ( $requestOptions->boundary === null ) {
+			return $keepDataValue;
+		}
+
+		// apply value boundary
+		$strc = $isNumeric ? 0 : strcmp( $value, $requestOptions->boundary );
+
+		if ( $requestOptions->ascending ) {
+			if ( $requestOptions->include_boundary ) {
+				$keepDataValue = $isNumeric ? ( $value >= $requestOptions->boundary ) : ( $strc >= 0 );
+			} else {
+				$keepDataValue = $isNumeric ? ( $value > $requestOptions->boundary ) : ( $strc > 0 );
+			}
+		} else {
+			if ( $requestOptions->include_boundary ) {
+				$keepDataValue = $isNumeric ? ( $value <= $requestOptions->boundary ) : ( $strc <= 0 );
+			} else {
+				$keepDataValue = $isNumeric ? ( $value < $requestOptions->boundary ) : ( $strc < 0 );
+			}
+		}
+
+		return $keepDataValue;
+	}
+
+	private static function getSortKeyForItem( $store, $item ) {
+
+		if ( $item instanceof DIWikiPage ) {
+			$label = $store->getWikiPageSortKey( $item );
+			$value = $label;
+		} else {
+			$label = ( $item instanceof DIBlob ) ? $item->getString() : '';
+			$value = $item->getSortKey();
+		}
+
+		return [ $label, $value ];
+	}
+
+	private static function applySortRestriction( $requestOptions, &$result, $sortres, $isNumeric ) {
+
+		if ( !$requestOptions->sort ) {
+			return null;
+		}
+
+		$flag = $isNumeric ? SORT_NUMERIC : SORT_LOCALE_STRING;
+
+		// SORT_NATURAL is selected on n-asc, n-desc
+		if ( isset( $requestOptions->natural ) ) {
+			$flag = SORT_NATURAL;
+		}
+
+		if ( $requestOptions->ascending ) {
+			asort( $sortres, $flag );
+		} else {
+			arsort( $sortres, $flag );
+		}
+
+		$newres = [];
+
+		foreach ( $sortres as $key => $value ) {
+			$newres[] = $result[$key];
+		}
+
+		$result = $newres;
+	}
+
+	private static function applyLimitRestriction( $requestOptions, &$result ) {
+
+		// In case of a `conditionConstraint` the restriction is set forth by the
+		// SELECT statement.
+		if ( isset( $requestOptions->conditionConstraint ) ) {
+			return $result;
+		}
+
+		if ( $requestOptions->limit > 0 ) {
+			return $result = array_slice( $result, $requestOptions->offset, $requestOptions->limit );
+		}
+
+		$result = array_slice( $result, $requestOptions->offset );
+	}
+
+}