public function refreshFields()
    {
        if ($this->id === null) {
            $this->original = [];
            return $this->fields = [];
        }
        
        $this->fields = static::query()->getById($this->id)->fields;
        $this->original = $this->fields;
        
        $this->fieldsAreFetched = true;
        
        return $this->fields;
    }