Allow to reference events from event

This might be useful to allow editors and integrators to create
something like "you might also be interested in" or "related events".

Classes/Domain/Model/Event.php

@@ -217,6 +217,11 @@ class Event extends AbstractEntity
      */
     protected $partner;
 
+    /**
+     * @var \TYPO3\CMS\Extbase\Persistence\ObjectStorage<Event>
+     */
+    protected $referencesEvents;
+
     /**
      * @var int
      */
@@ -251,6 +256,7 @@ class Event extends AbstractEntity
     protected function initStorageObjects()
     {
         $this->dates = new ObjectStorage();
+        $this->referencesEvents = new ObjectStorage();
     }
 
     /**
@@ -674,6 +680,14 @@ class Event extends AbstractEntity
         return $this->partner;
     }
 
+    /**
+     * @return ObjectStorage<Event>
+     */
+    public function getReferencesEvents(): ObjectStorage
+    {
+        return $this->referencesEvents;
+    }
+
     /**
      * @param \Wrm\Events\Domain\Model\Organizer $organizer
      * @return void

Configuration/TCA/tx_events_domain_model_event.php

@@ -63,6 +63,7 @@ return [
                     region,
                     partner,
                     categories,
+                    references_events,
                     pages,
                 --div--;' . $l10nPath . ':tx_events_domain_model_event.tabs.media,
                     images,
@@ -524,6 +525,21 @@ return [
             ],
         ],
 
+        'references_events' => [
+            'exclude' => true,
+            'label' => $l10nPath . ':tx_events_domain_model_event.references_events',
+            'config' => [
+                'type' => 'group',
+                'internal_type' => 'db',
+                'allowed' => 'tx_events_domain_model_event',
+                'suggestOptions' => [
+                    'tx_events_domain_model_event' => [
+                        'searchCondition' => 'tx_events_domain_model_event.sys_language_uid IN (0, -1)',
+                    ],
+                ],
+            ],
+        ],
+
         'partner' => [
             'exclude' => true,
             'label' => $l10nPath . ':tx_events_domain_model_event.partner',

Resources/Private/Language/de.locallang_csh_event.xlf

@@ -159,6 +159,10 @@
                 <source>Partner</source>
                 <target>Partner</target>
             </trans-unit>
+            <trans-unit id="tx_events_domain_model_event.references_events">
+                <source>Related Events</source>
+                <target>Ähnliche Veranstaltungen</target>
+            </trans-unit>
         </body>
     </file>
 </xliff>

Resources/Private/Language/locallang_csh_event.xlf

@@ -117,6 +117,9 @@
             <trans-unit id="tx_events_domain_model_event.partner">
                 <source>Partner</source>
             </trans-unit>
+            <trans-unit id="tx_events_domain_model_event.references_events">
+                <source>Related Events</source>
+            </trans-unit>
         </body>
     </file>
 </xliff>

ext_tables.sql

@@ -32,6 +32,7 @@ CREATE TABLE tx_events_domain_model_event (
 	organizer int(11) unsigned DEFAULT '0',
 	partner text,
 	region int(11) unsigned DEFAULT '0',
+	references_events text,
     KEY dataHandler (l10n_parent, t3ver_oid, deleted, t3ver_wsid, t3ver_state)
 );