A lot of things.

Service/Club/ApproverService.php

@@ -0,0 +1,64 @@
+<?php
+
+namespace RomhackPlaza\Master\Service\Club;
+
+use RomhackPlaza\Master\Entity\Club;
+use XF\App;
+use XF\Entity\Forum;
+use XF\Entity\Node;
+use XF\Service\AbstractService;
+use XF\Util\File;
+
+class ApproverService extends AbstractService
+{
+
+    /**
+     * @var Club
+     */
+    protected $club;
+
+    public function __construct(App $app, Club $club)
+    {
+        parent::__construct($app);
+
+        $this->club = $club;
+    }
+
+    public function approve(): bool
+    {
+        if( $this->club->club_state !== 'moderated' ) {
+            return false;
+        }
+
+        $this->club->club_state = 'visible';
+        $this->club->save();
+
+        /** @var Node $node */
+        $node = $this->em()->create('XF:Node');
+
+        $node->node_type_id = 'Forum';
+        $node->title = $this->club->title;
+        $node->description = $this->club->description;
+        $node->parent_node_id = \XF::options()->rhpz_club_node_id ?? 0;
+        $node->display_order = 1;
+        $node->save();
+
+        /** @var Forum $forum */
+        $forum = $this->em()->create('XF:Forum');
+        $forum->node_id = $node->node_id;
+        $forum->allow_posting = true;
+        $forum->save();
+
+        $this->club->node_id = $node->node_id;
+        $this->club->save();
+
+        $user = $this->club->User;
+        if( $user ){
+            /** @var ModeratorService $modManage */
+            $modManage = \XF::app()->service('RomhackPlaza\Master:Club\Moderator', $this->club, $user );
+            $modManage->addModerator( $error );
+        }
+
+        return true;
+    }
+}