1 files changed, 153 insertions, 0 deletions
diff --git a/www/wiki/includes/search/SearchIndexFieldDefinition.php b/www/wiki/includes/search/SearchIndexFieldDefinition.php
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+++ b/www/wiki/includes/search/SearchIndexFieldDefinition.php
@@ -0,0 +1,153 @@
+<?php
+
+/**
+ * Basic infrastructure of the field definition.
+ *
+ * Specific engines should extend this class and at at least,
+ * override the getMapping method, but can reuse other parts.
+ *
+ * @since 1.28
+ */
+abstract class SearchIndexFieldDefinition implements SearchIndexField {
+
+	/**
+	 * Name of the field
+	 *
+	 * @var string
+	 */
+	protected $name;
+
+	/**
+	 * Type of the field, one of the constants above
+	 *
+	 * @var int
+	 */
+	protected $type;
+
+	/**
+	 * Bit flags for the field.
+	 *
+	 * @var int
+	 */
+	protected $flags = 0;
+
+	/**
+	 * Subfields
+	 * @var SearchIndexFieldDefinition[]
+	 */
+	protected $subfields = [];
+
+	/**
+	 * @var callable
+	 */
+	private $mergeCallback;
+
+	/**
+	 * @param string $name Field name
+	 * @param int $type Index type
+	 */
+	public function __construct( $name, $type ) {
+		$this->name = $name;
+		$this->type = $type;
+	}
+
+	/**
+	 * Get field name
+	 * @return string
+	 */
+	public function getName() {
+		return $this->name;
+	}
+
+	/**
+	 * Get index type
+	 * @return int
+	 */
+	public function getIndexType() {
+		return $this->type;
+	}
+
+	/**
+	 * Set global flag for this field.
+	 *
+	 * @param int $flag Bit flag to set/unset
+	 * @param bool $unset True if flag should be unset, false by default
+	 * @return $this
+	 */
+	public function setFlag( $flag, $unset = false ) {
+		if ( $unset ) {
+			$this->flags &= ~$flag;
+		} else {
+			$this->flags |= $flag;
+		}
+		return $this;
+	}
+
+	/**
+	 * Check if flag is set.
+	 * @param int $flag
+	 * @return int 0 if unset, !=0 if set
+	 */
+	public function checkFlag( $flag ) {
+		return $this->flags & $flag;
+	}
+
+	/**
+	 * Merge two field definitions if possible.
+	 *
+	 * @param SearchIndexField $that
+	 * @return SearchIndexField|false New definition or false if not mergeable.
+	 */
+	public function merge( SearchIndexField $that ) {
+		if ( !empty( $this->mergeCallback ) ) {
+			return call_user_func( $this->mergeCallback, $this, $that );
+		}
+		// TODO: which definitions may be compatible?
+		if ( ( $that instanceof self ) && $this->type === $that->type &&
+			$this->flags === $that->flags && $this->type !== self::INDEX_TYPE_NESTED
+		) {
+			return $that;
+		}
+		return false;
+	}
+
+	/**
+	 * Get subfields
+	 * @return SearchIndexFieldDefinition[]
+	 */
+	public function getSubfields() {
+		return $this->subfields;
+	}
+
+	/**
+	 * Set subfields
+	 * @param SearchIndexFieldDefinition[] $subfields
+	 * @return $this
+	 */
+	public function setSubfields( array $subfields ) {
+		$this->subfields = $subfields;
+		return $this;
+	}
+
+	/**
+	 * @param SearchEngine $engine
+	 *
+	 * @return array
+	 */
+	abstract public function getMapping( SearchEngine $engine );
+
+	/**
+	 * Set field-specific merge strategy.
+	 * @param callable $callback
+	 */
+	public function setMergeCallback( $callback ) {
+		$this->mergeCallback = $callback;
+	}
+
+	/**
+	 * @inheritDoc
+	 */
+	public function getEngineHints( SearchEngine $engine ) {
+		return [];
+	}
+}