Codeigniter->form_validation->custom callback for check date which supports min date, max date and ensure formatted as YYYY-MM-DD

Codeigniter check_date callback

public function check_date($str)
    {
        $dts = date_create_from_format("Y-m-d", $str);
        if ($dts == FALSE)
        {
            $this->form_validation->set_message('check_date', 'The {field} field is in an unreadable format');
            return false;
        }
        $maxDate = date_create_from_format('Y-m-d', date('Y-m-d', strtotime('+1 day')));
        if ($dts > $maxDate)
        {
            $this->form_validation->set_message('check_date', 'The {field} field cannot be in the future');
            return false;
        }

        $minDate = date_create_from_format('Y-m-d', date('Y-m-d', strtotime("-1 years")));
        if ($dts < $minDate)
        {
            $this->form_validation->set_message('check_date', 'The {field} field cannot be more than 1 year ago');
        }
        
        return true;
    }