1 files changed, 261 insertions, 0 deletions
diff --git a/www/wiki/extensions/SemanticMediaWiki/src/DataValues/Number/UnitConverter.php b/www/wiki/extensions/SemanticMediaWiki/src/DataValues/Number/UnitConverter.php
new file mode 100644
index 00000000..066c8937
--- /dev/null
+++ b/www/wiki/extensions/SemanticMediaWiki/src/DataValues/Number/UnitConverter.php
@@ -0,0 +1,261 @@
+<?php
+
+namespace SMW\DataValues\Number;
+
+use SMW\ApplicationFactory;
+use SMW\CachedPropertyValuesPrefetcher;
+use SMW\DIProperty;
+use SMWDIBlob as DIBlob;
+use SMWNumberValue as NumberValue;
+
+/**
+ * Returns conversion data from a cache instance to enable a responsive query
+ * feedback and eliminate possible repeated DB requests.
+ *
+ * The cache is evicted as soon as the property that contains "Corresponds to"
+ * is altered.
+ *
+ * @license GNU GPL v2+
+ * @since 2.4
+ *
+ * @author mwjames
+ */
+class UnitConverter {
+
+	/**
+	 * @var NumberValue
+	 */
+	private $numberValue;
+
+	/**
+	 * @var CachedPropertyValuesPrefetcher
+	 */
+	private $cachedPropertyValuesPrefetcher;
+
+	/**
+	 * @var array
+	 */
+	private $errors = [];
+
+	/**
+	 * @var array
+	 */
+	private $unitIds = [];
+
+	/**
+	 * @var array
+	 */
+	private $unitFactors = [];
+
+	/**
+	 * @var false|string
+	 */
+	private $mainUnit = false;
+
+	/**
+	 * @var array
+	 */
+	protected $prefixalUnitPreference = [];
+
+	/**
+	 * @since 2.4
+	 *
+	 * @param NumberValue $numberValue
+	 * @param CachedPropertyValuesPrefetcher|null $cachedPropertyValuesPrefetcher
+	 */
+	public function __construct( NumberValue $numberValue, CachedPropertyValuesPrefetcher $cachedPropertyValuesPrefetcher = null ) {
+		$this->numberValue = $numberValue;
+		$this->cachedPropertyValuesPrefetcher = $cachedPropertyValuesPrefetcher;
+
+		if ( $this->cachedPropertyValuesPrefetcher === null ) {
+			$this->cachedPropertyValuesPrefetcher = ApplicationFactory::getInstance()->getCachedPropertyValuesPrefetcher();
+		}
+	}
+
+	/**
+	 * @since 2.4
+	 *
+	 * @return array
+	 */
+	public function getErrors() {
+		return $this->errors;
+	}
+
+	/**
+	 * @since 2.4
+	 *
+	 * @return array
+	 */
+	public function getUnitIds() {
+		return $this->unitIds;
+	}
+
+	/**
+	 * @since 2.4
+	 *
+	 * @return array
+	 */
+	public function getUnitFactors() {
+		return $this->unitFactors;
+	}
+
+	/**
+	 * @since 2.4
+	 *
+	 * @return string
+	 */
+	public function getMainUnit() {
+		return $this->mainUnit;
+	}
+
+	/**
+	 * @since 2.4
+	 *
+	 * @return array
+	 */
+	public function getPrefixalUnitPreference() {
+		return $this->prefixalUnitPreference;
+	}
+
+	/**
+	 * @since 2.4
+	 *
+	 * @param DIProperty $property
+	 */
+	public function fetchConversionData( DIProperty $property ) {
+
+		$this->unitIds = [];
+		$this->unitFactors = [];
+		$this->mainUnit = false;
+		$this->prefixalUnitPreference = [];
+		$this->errors = [];
+
+		$factors = $this->cachedPropertyValuesPrefetcher->getPropertyValues(
+			$property->getDiWikiPage(),
+			new DIProperty( '_CONV' )
+		);
+
+		$this->numberValue->setContextPage( $property->getDiWikiPage() );
+
+		if ( $factors === null || $factors === [] ) { // no custom type
+			return $this->errors[] = 'smw_nounitsdeclared';
+		}
+
+		$number = '';
+		$unit = '';
+		$asPrefix = false;
+
+		foreach ( $factors as $di ) {
+
+			// ignore corrupted data and bogus inputs
+			if ( !( $di instanceof DIBlob ) ||
+			     ( $this->numberValue->parseNumberValue( $di->getString(), $number, $unit, $asPrefix ) != 0 ) ||
+			     ( $number == 0 ) ) {
+				continue;
+			}
+
+			$this->matchUnitAliases(
+				$number,
+				$asPrefix,
+				preg_split( '/\s*,\s*/u', $unit )
+			);
+		}
+
+		// No unit with factor 1? Make empty string the main unit.
+		if ( $this->mainUnit === false ) {
+			$this->mainUnit = '';
+		}
+
+		// Always add an extra empty unit; not as a synonym for the main unit
+		// but as a new unit with ID '' so if users do not give any unit, the
+		// conversion tooltip will still display the main unit for clarity
+		// (the empty unit is never displayed; we filter it when making
+		// conversion values)
+		$this->unitFactors = [ '' => 1 ] + $this->unitFactors;
+		$this->unitIds[''] = '';
+	}
+
+	/**
+	 * @since 2.4
+	 *
+	 * @param DIProperty|null $property
+	 */
+	public function initConversionData( DIProperty $property = null ) {
+
+		if ( $property === null || ( $propertyDiWikiPage = $property->getDiWikiPage() ) === null ) {
+			return;
+		}
+
+		$blobStore = $this->cachedPropertyValuesPrefetcher->getBlobStore();
+
+		// Ensure that when the property page is altered the cache gets
+		// evicted
+		$hash = $this->cachedPropertyValuesPrefetcher->getRootHashFrom(
+			$propertyDiWikiPage
+		);
+
+		$container = $blobStore->read(
+			$hash
+		);
+
+		$key = '--conv';
+
+		if ( $container->has( $key ) ) {
+			$data = $container->get( $key );
+			$this->unitIds = $data['ids'];
+			$this->unitFactors = $data['factors'];
+			$this->mainUnit = $data['main'];
+			$this->prefixalUnitPreference = $data['prefix'];
+			return;
+		}
+
+		$this->fetchConversionData( $property );
+
+		if ( $this->errors !== [] ) {
+			return;
+		}
+
+		$data = [
+			'ids' => $this->unitIds,
+			'factors' => $this->unitFactors,
+			'main' => $this->mainUnit,
+			'prefix' => $this->prefixalUnitPreference
+		];
+
+		$container->set( $key, $data );
+
+		$blobStore->save(
+			$container
+		);
+	}
+
+	private function matchUnitAliases( $number, $asPrefix, array $unitAliases ) {
+		$first = true;
+
+		foreach ( $unitAliases as $unit ) {
+			$unit = $this->numberValue->normalizeUnit( $unit );
+
+			// Legacy match the preserve some behaviour where spaces where normalized
+			// no matter what
+			$normalizedUnit = $this->numberValue->normalizeUnit(
+				str_replace( [ '&nbsp;', '&#160;', '&thinsp;', ' ' ], '', $unit )
+			);
+
+			if ( $first ) {
+				$unitid = $unit;
+				if ( $number == 1 ) { // add main unit to front of array (displayed first)
+					$this->mainUnit = $unit;
+					$this->unitFactors = [ $unit => 1 ] + $this->unitFactors;
+				} else { // non-main units are not ordered (can be modified via display units)
+					$this->unitFactors[$unit] = $number;
+				}
+				$first = false;
+			}
+			// add all known units to m_unitids to simplify checking for them
+			$this->unitIds[$unit] = $unitid;
+			$this->unitIds[$normalizedUnit] = $unitid;
+			$this->prefixalUnitPreference[$unit] = $asPrefix;
+		}
+	}
+
+}