Data.php

<?PHP
/*- 
 * Copyright (c) 2017 Etienne Bagnoud <etienne@artisan-numerique.ch>
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */
Namespace artnum;

class Data {
   /* Convert string/datetime into ISO 8601 string, UTC with Z ending */
   function datetime ($value) {
      if (!($value instanceof \DateTime)) {
         if (is_null($value) || empty($value)) { return $value; }
         if (is_integer($value) || is_numeric($value)) { $value = '@' . strval($value); }
         if (!is_string($value)) { return $value; }

         try {
            $dt = new \DateTime($value);
            $dt->setTimeZone(new \DateTimeZone('UTC'));
            $value = $dt->format('c');
         } catch (\Exception $e) {
            return $value;
         }

      }
      $ret = preg_replace('/Z$/', '+00:00', $value);
      if (!is_null($ret)) {
         return $ret;
      }

      return $value;
   }
}

?>