Merge pull request #1087 - add getVariantBase()

This implements feature request #237 by adding the requested method:
`IItem::getVariantBase()`.

src/MetaModels/IItem.php

@@ -3,7 +3,7 @@
 /**
  * This file is part of MetaModels/core.
  *
- * (c) 2012-2015 The MetaModels team.
+ * (c) 2012-2017 The MetaModels team.
  *
  * For the full copyright and license information, please view the LICENSE
  * file that was distributed with this source code.
@@ -14,7 +14,8 @@
  * @subpackage Core
  * @author     Christian Schiffler <c.schiffler@cyberspectrum.de>
  * @author     Stefan Heimes <stefan_heimes@hotmail.com>
- * @copyright  2012-2015 The MetaModels team.
+ * @author     Richard Henkenjohann <richardhenkenjohann@googlemail.com>
+ * @copyright  2012-2017 The MetaModels team.
  * @license    https://github.com/MetaModels/core/blob/master/LICENSE LGPL-3.0
  * @filesource
  */
@@ -107,10 +108,19 @@ public function isVariantBase();
      *
      * @param \MetaModels\Filter\IFilter $objFilter The filter settings to be applied.
      *
-     * @return \MetaModels\IItems A list of all variants for this item.
+     * @return \MetaModels\IItems|null A list of all variants for this item or null if the item cannot handle variants.
      */
     public function getVariants($objFilter);
 
+    /**
+     * Fetch the meta model variant base for this item.
+     *
+     * Note: For a non-variant item the variant base is the item itself.
+     *
+     * @return IItem The variant base.
+     */
+    public function getVariantBase();
+
     /**
      * Save the current data for every attribute to the data sink.
      *

src/MetaModels/Item.php

@@ -285,7 +285,7 @@ public function isVariantBase()
      *
      * @param IFilter $objFilter The filter settings to be applied.
      *
-     * @return IItems A list of all variants for this item.
+     * @return IItems|null A list of all variants for this item.
      */
     public function getVariants($objFilter)
     {
@@ -296,6 +296,22 @@ public function getVariants($objFilter)
         return null;
     }
 
+    /**
+     * Fetch the meta model variant base for this item.
+     *
+     * Note: For a non-variant item the variant base is the item itself.
+     *
+     * @return IItem The variant base.
+     */
+    public function getVariantBase()
+    {
+        if (!$this->isVariantBase()) {
+            return $this->getMetaModel()->findById($this->get('vargroup'));
+        }
+
+        return $this;
+    }
+
     /**
      * Find all Variants including the variant base.
      *