1 files changed, 137 insertions, 0 deletions
diff --git a/www/wiki/extensions/SemanticMediaWiki/src/Exporter/Element/ExpElement.php b/www/wiki/extensions/SemanticMediaWiki/src/Exporter/Element/ExpElement.php
new file mode 100644
index 00000000..1e37f10d
--- /dev/null
+++ b/www/wiki/extensions/SemanticMediaWiki/src/Exporter/Element/ExpElement.php
@@ -0,0 +1,137 @@
+<?php
+
+namespace SMW\Exporter\Element;
+
+use RuntimeException;
+use SMW\Exporter\Element;
+use SMWDataItem as DataItem;
+
+/**
+ * ExpElement is a class for representing single elements that appear in
+ * exported data, such as individual resources, data literals, or blank nodes.
+ *
+ * A single element for export, e.g. a data literal, instance name, or blank
+ * node. This abstract base class declares the basic common functionality of
+ * export elements (which is not much, really).
+ * @note This class should not be instantiated directly.
+ *
+ * @license GNU GPL v2+
+ * @since 2.2
+ *
+ * @author Markus Krötzsch
+ * @author mwjames
+ */
+abstract class ExpElement implements Element {
+
+	/**
+	 * The DataItem that this export element is associated with, if
+	 * any. Might be unset if not given yet.
+	 *
+	 * @var DataItem|null
+	 */
+	protected $dataItem;
+
+	/**
+	 * @since 1.6
+	 *
+	 * @param DataItem|null $dataItem
+	 */
+	public function __construct( DataItem $dataItem = null ) {
+		$this->dataItem = $dataItem;
+	}
+
+	/**
+	 * Get a DataItem object that represents the contents of this export
+	 * element in SMW, or null if no such data item could be found.
+	 *
+	 * @return DataItem|null
+	 */
+	public function getDataItem() {
+		return $this->dataItem;
+	}
+
+	/**
+	 * @since 2.2
+	 *
+	 * @return string
+	 */
+	public function getHash() {
+		return md5( json_encode( $this->getSerialization() ) );
+	}
+
+	/**
+	 * @since  2.2
+	 *
+	 * @return array
+	 */
+	public function getSerialization() {
+
+		$dataItem = null;
+
+		if ( $this->getDataItem() !== null ) {
+			$dataItem = [
+				'type' => $this->getDataItem()->getDIType(),
+				'item' => $this->getDataItem()->getSerialization()
+			];
+		}
+
+		return [
+			'dataitem' => $dataItem
+		];
+	}
+
+	/**
+	 * @see ExpElement::newFromSerialization
+	 */
+	protected static function deserialize( $serialization ) {
+
+		$dataItem = null;
+
+		if ( !array_key_exists( 'dataitem', $serialization ) ) {
+			throw new RuntimeException( "The serialization format is missing a dataitem element" );
+		}
+
+		// If it is null, isset will ignore it
+		if ( isset( $serialization['dataitem'] ) ) {
+			$dataItem = DataItem::newFromSerialization(
+				$serialization['dataitem']['type'],
+				$serialization['dataitem']['item']
+			);
+		}
+
+		return $dataItem;
+	}
+
+	/**
+	 * @since  2.2
+	 *
+	 * @param array $serialization
+	 *
+	 * @return ExpElement
+	 */
+	public static function newFromSerialization( array $serialization ) {
+
+		if ( !isset( $serialization['type'] ) ) {
+			throw new RuntimeException( "The serialization format is missing a type element" );
+		}
+
+		switch ( $serialization['type'] ) {
+			case Element::TYPE_RESOURCE:
+				$elementClass = ExpResource::class;
+				break;
+			case Element::TYPE_NSRESOURCE:
+				$elementClass = ExpNsResource::class;
+				break;
+			case Element::TYPE_LITERAL:
+				$elementClass = ExpLiteral::class;
+				break;
+			default:
+				throw new RuntimeException( "Unknown type" );
+		}
+
+		$serialization['dataitem'] = self::deserialize( $serialization );
+
+		return $elementClass::deserialize( $serialization );
+	}
+
+}