Allow hotlinking images

src/ThumbnailHelper.php

@@ -9,6 +9,22 @@ namespace dokuwiki\plugin\luxtools;
  */
 class ThumbnailHelper
 {
+    /**
+     * Check if a string is a HTTP/HTTPS URL.
+     *
+     * @param string $url
+     * @return bool
+     */
+    public static function isRemoteUrl(string $url): bool
+    {
+        if ($url === '') return false;
+        $parts = @parse_url($url);
+        if (!is_array($parts)) return false;
+        if (empty($parts['scheme']) || empty($parts['host'])) return false;
+        $scheme = strtolower((string)$parts['scheme']);
+        return in_array($scheme, ['http', 'https'], true);
+    }
+
     /**
      * Get thumbnail URL and metadata for rendering.
      *