Introduce Type\MetaRecordIndexInterface

Uses by meta filter API to address clearly an object related
meta record #56

inc/Import/Type/MetaRecordIndexInterface.php

@@ -0,0 +1,35 @@
+<?php # -*- coding: utf-8 -*-
+
+namespace W2M\Import\Type;
+
+/**
+ * Interface MetaRecordIndexInterface
+ *
+ * Describes a »pointer« to a concrete ImportMeta record
+ *
+ * @package W2M\Import\Type
+ */
+interface MetaRecordIndexInterface {
+
+	/**
+	 * The type the meta data belongs to
+	 *
+	 * @return string
+	 */
+	public function type();
+
+	/**
+	 * @return int
+	 */
+	public function object_id();
+
+	/**
+	 * @return string
+	 */
+	public function key();
+
+	/**
+	 * @return int
+	 */
+	public function index();
+}

inc/Import/Type/WpMetaRecordIndex.php

@@ -0,0 +1,75 @@
+<?php # -*- coding: utf-8 -*-
+
+namespace W2M\Import\Type;
+
+class WpMetaRecordIndex implements MetaRecordIndexInterface {
+
+	/**
+	 * @var string
+	 */
+	private $type = '';
+
+	/**
+	 * @var string
+	 */
+	private $key = '';
+
+	/**
+	 * @var int
+	 */
+	private $object_id = 0;
+
+	/**
+	 * @var int
+	 */
+	private $index = 0;
+
+	/**
+	 * @param $key
+	 * @param $object_id
+	 * @param int $index
+	 * @param string $type
+	 */
+	public function __construct( $key, $object_id, $index = 0, $type = 'post' ) {
+
+		$this->key       = (string) $key;
+		$this->object_id = (int) $object_id;
+		$this->index     = (int) $index;
+		$this->type      = (string) $type;
+	}
+
+	/**
+	 * The type the meta data belongs to
+	 *
+	 * @return string
+	 */
+	public function type() {
+
+		return $this->type;
+	}
+
+	/**
+	 * @return int
+	 */
+	public function object_id() {
+
+		return $this->object_id;
+	}
+
+	/**
+	 * @return string
+	 */
+	public function key() {
+
+		return $this->key;
+	}
+
+	/**
+	 * @return int
+	 */
+	public function index() {
+
+		return $this->index;
+	}
+
+}