Flush the embed client assets when settings are changed

extensions/embed/bootstrap.php

@@ -14,4 +14,5 @@ use Illuminate\Contracts\Events\Dispatcher;
 
 return function (Dispatcher $events) {
     $events->subscribe(Listener\AddEmbedRoute::class);
-};
+    $events->subscribe(Listener\FlushEmbedAssetsWhenSettingsAreChanged::class);
+};

extensions/embed/src/Listener/FlushEmbedAssetsWhenSettingsAreChanged.php

@@ -0,0 +1,58 @@
+<?php
+/*
+ * This file is part of Flarum.
+ *
+ * (c) Toby Zerner <toby.zerner@gmail.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Flarum\Embed\Listener;
+
+use Flarum\Embed\DiscussionController;
+use Flarum\Event\ExtensionWasDisabled;
+use Flarum\Event\ExtensionWasEnabled;
+use Flarum\Event\SettingWasSet;
+use Illuminate\Contracts\Events\Dispatcher;
+
+class FlushEmbedAssetsWhenSettingsAreChanged
+{
+    /**
+     * @var DiscussionController
+     */
+    protected $controller;
+
+    /**
+     * @param DiscussionController $controller
+     */
+    public function __construct(DiscussionController $controller)
+    {
+        $this->controller = $controller;
+    }
+
+    /**
+     * @param Dispatcher $events
+     */
+    public function subscribe(Dispatcher $events)
+    {
+        $events->listen(SettingWasSet::class, [$this, 'flushCss']);
+        $events->listen(ExtensionWasEnabled::class, [$this, 'flushAssets']);
+        $events->listen(ExtensionWasDisabled::class, [$this, 'flushAssets']);
+    }
+
+    /**
+     * @param SettingWasSet $event
+     */
+    public function flushCss(SettingWasSet $event)
+    {
+        if (preg_match('/^theme_|^custom_less$/i', $event->key)) {
+            $this->controller->flushCss();
+        }
+    }
+
+    public function flushAssets()
+    {
+        $this->controller->flushAssets();
+    }
+}