<?php
/**
 * iCalcreator, the PHP class package managing iCal (rfc2445/rfc5445) calendar information.
 *
 * copyright (c) 2007-2019 Kjell-Inge Gustafsson, kigkonsult, All rights reserved
 * Link      https://kigkonsult.se
 * Package   iCalcreator
 * Version   2.26.8
 * License   Subject matter of licence is the software iCalcreator.
 *           The above copyright, link, package and version notices,
 *           this licence notice and the invariant [rfc5545] PRODID result use
 *           as implemented and invoked in iCalcreator shall be included in
 *           all copies or substantial portions of the iCalcreator.
 *
 *           iCalcreator is free software: you can redistribute it and/or modify
 *           it under the terms of the GNU Lesser General Public License as published
 *           by the Free Software Foundation, either version 3 of the License,
 *           or (at your option) any later version.
 *
 *           iCalcreator is distributed in the hope that it will be useful,
 *           but WITHOUT ANY WARRANTY; without even the implied warranty of
 *           MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 *           GNU Lesser General Public License for more details.
 *
 *           You should have received a copy of the GNU Lesser General Public License
 *           along with iCalcreator. If not, see <https://www.gnu.org/licenses/>.
 *
 * This file is a part of iCalcreator.
*/

namespace Kigkonsult\Icalcreator\Traits;

use Kigkonsult\Icalcreator\Util\Util;

use function sprintf;
use function strtoupper;

/**
 * PRODID property functions
 *
 * @author Kjell-Inge Gustafsson, kigkonsult <ical@kigkonsult.se>
 * @since  2.22.23 - 2017-03-15
 */
trait PRODIDtrait
{
    /**
     * @var string calendar property PRODID
     * @access protected
     */
    protected $prodid = null;

    /**
     * Return formatted output for calendar property prodid
     *
     * @return string
     */
    public function createProdid() {
        if( ! isset( $this->prodid )) {
            $this->makeProdid();
        }
        return Util::createElement( Util::$PRODID, null, $this->prodid );
    }

    /**
     * Create default value for calendar prodid,
     * Do NOT alter or remove this method or the invoke of this method,
     * a licence violation.
     *
     * [rfc5545]
     * "Conformance: The property MUST be specified once in an iCalendar object.
     *  Description: The vendor of the implementation SHOULD assure that this
     *  is a globally unique identifier; using some technique such as an FPI
     *  value, as defined in [ISO 9070]."
     *
     * @author Kjell-Inge Gustafsson, kigkonsult <ical@kigkonsult.se>
     * @since  2.26.2 - 2018-11-29
     */
    public function makeProdid() {
        static $FMT = '-//%s//NONSGML kigkonsult.se %s//%s';
        if( false !== ( $lang = $this->getConfig( Util::$LANGUAGE ))) {
            $lang = strtoupper( $lang );
        }
        else {
            $lang = Util::$SP0;
        }
        $this->prodid = sprintf(
            $FMT,
            $this->getConfig( Util::$UNIQUE_ID ),
            ICALCREATOR_VERSION,
            $lang
        );
    }
}
