public static function deleteUnusedFiles($originalContent, $content)
    {
        $originalFiles = self::findExternalLinks($originalContent);

        $deleted = [];

        if (empty($originalFiles)) {
            return $deleted;
        }

        $currentFiles = self::findExternalLinks($content);

        $diff = array_diff($originalFiles, $currentFiles);
        if (empty($diff)) {
            return $deleted;
        }

        foreach ($diff as $path) {
            // Skip absolute path
            if (strpos($path, 'http') === 0) {
                continue;
            }

            $file = File::find(ASSETS_DIR . $path);
            if ($file) {
                $deleted[] = $path;
                $file->delete();
            }
        }

        return $deleted;
    }