public function getAssignmentAttribute()
    {
        if (! $this->exists) {
            return static::ALL_PAGES;
        }

        $count = $this->menuPivot()->count();
        if ($count === 0) {
            return static::NO_PAGES;
        } elseif ($count > 1) {
            return static::SELECTED_PAGES;
        } elseif ($count === 1) {
            $pivot = $this->menuPivot()->first();
            if ($pivot->menu_id > 0) {
                return static::SELECTED_PAGES;
            }
        }

        return static::ALL_PAGES;
    }