Added the possibility to delete AttachmentTypes recusivly.

src/Services/StructuralElementRecursionHelper.php

@@ -0,0 +1,102 @@
+<?php
+/**
+ *
+ * part-db version 0.1
+ * Copyright (C) 2005 Christoph Lechner
+ * http://www.cl-projects.de/
+ *
+ * part-db version 0.2+
+ * Copyright (C) 2009 K. Jacobs and others (see authors.php)
+ * http://code.google.com/p/part-db/
+ *
+ * Part-DB Version 0.4+
+ * Copyright (C) 2016 - 2019 Jan Böhmer
+ * https://github.com/jbtronics
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA
+ *
+ */
+
+namespace App\Services;
+
+
+use App\Entity\StructuralDBElement;
+use Doctrine\ORM\EntityManagerInterface;
+
+class StructuralElementRecursionHelper
+{
+
+    protected $em;
+
+    public function __construct(EntityManagerInterface $em)
+    {
+        $this->em = $em;
+    }
+
+    /**
+     * Executes an function (callable) recursivly for $element and every of its children.
+     *
+     * @param StructuralDBElement $element The element on which the func should be executed
+     * @param callable $func The function which should be executed for each element.
+     * $func has the signature function(StructuralDBElement $element) : void
+     * @param int $max_depth The maximum depth for which should be recursivly called. So if this is set to 5, after the
+     * 5th level the execution is stopped.
+     * @param bool $call_from_bottom If set to true the bottom elements (elements with high level) will be called first.
+     * Set to false if you want to call the top elements first.
+     */
+    public function execute(StructuralDBElement $element, callable $func, int $max_depth = -1, $call_from_bottom = true) : void
+    {
+        //Cancel if we reached our maximal allowed level. Must be zero because -1 is infinity levels
+        if ($max_depth == 0) {
+            return;
+        }
+
+        //Get children of the current class:
+        $children = $element->getChildren();
+
+        //If we should call from top we execute the func here.
+        if (!$call_from_bottom) {
+            $func($element);
+        }
+
+        foreach ($children as $child) {
+            $this->execute($child, $func, $max_depth - 1);
+        }
+
+        //Otherwise we call it here
+        if ($call_from_bottom) {
+            $func($element);
+        }
+    }
+
+    /**
+     * Deletes the $element and all its subelements recursivly.
+     * @param StructuralDBElement $element The element which should be deleted.
+     * @param bool $flush When set to true the changes will also be flushed to DB. Set to false if you want to flush
+     * later.
+     */
+    public function delete(StructuralDBElement $element, bool $flush = true) : void
+    {
+        $em = $this->em;
+
+        $this->execute($element, static function(StructuralDBElement $element) use ($em) {
+            $em->remove($element);
+        });
+
+        if($flush) {
+            $em->flush();
+        }
+    }
+}