Do not remove associated Project BOM entries if part is deleted

Instead the part name is put into the name field. This fixes issue #1068

Author: jbtronics

src/Entity/Parts/PartTraits/ProjectTrait.php

@@ -15,7 +15,7 @@ trait ProjectTrait
     /**
      * @var Collection<ProjectBOMEntry> $project_bom_entries
      */
-    #[ORM\OneToMany(mappedBy: 'part', targetEntity: ProjectBOMEntry::class, cascade: ['remove'], orphanRemoval: true)]
+    #[ORM\OneToMany(targetEntity: ProjectBOMEntry::class, mappedBy: 'part')]
     protected Collection $project_bom_entries;
 
     /**

src/EntityListeners/PartProjectBOMEntryUnlinkListener.php

@@ -0,0 +1,59 @@
+<?php
+/*
+ * This file is part of Part-DB (https://github.com/Part-DB/Part-DB-symfony).
+ *
+ *  Copyright (C) 2019 - 2025 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 Affero General Public License as published
+ *  by the Free Software Foundation, either version 3 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 Affero General Public License for more details.
+ *
+ *  You should have received a copy of the GNU Affero General Public License
+ *  along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+declare(strict_types=1);
+
+
+namespace App\EntityListeners;
+
+use App\Entity\Parts\Part;
+use Doctrine\Bundle\DoctrineBundle\Attribute\AsEntityListener;
+use Doctrine\ORM\Event\PreRemoveEventArgs;
+
+/**
+ * If an part is deleted, this listener makes sure that all ProjectBOMEntries that reference this part, are updated
+ * to not reference the part anymore, but instead store the part name in the name field.
+ */
+#[AsEntityListener(event: "preRemove", entity: Part::class)]
+class PartProjectBOMEntryUnlinkListener
+{
+    public function preRemove(Part $part, PreRemoveEventArgs $event): void
+    {
+        // Iterate over all ProjectBOMEntries that use this part and put the part name into the name field
+        foreach ($part->getProjectBomEntries() as $bom_entry) {
+            $old_name = $bom_entry->getName();
+            if ($old_name === null || trim($old_name) === '') {
+                $bom_entry->setName($part->getName());
+            } else {
+                $bom_entry->setName($old_name . ' (' . $part->getName() . ')');
+            }
+
+            $old_comment = $bom_entry->getComment();
+            if ($old_comment === null || trim($old_comment) === '') {
+                $bom_entry->setComment('Part was deleted: ' . $part->getName());
+            } else {
+                $bom_entry->setComment($old_comment . "\n\n Part was deleted: " . $part->getName());
+            }
+
+            //Remove the part reference
+            $bom_entry->setPart(null);
+        }
+    }
+}