<?php
  /*
   * Project:     MagpieRSS: a simple RSS integration tool
   * File:        rss_utils.inc, utility methods for working with RSS
   * Author:      Kellan Elliott-McCrea <kellan@protest.net>
   * Version:     0.51
   * License:     GPL
   *
   * The lastest version of MagpieRSS can be obtained from:
   * http://magpierss.sourceforge.net
   *
   * For questions, help, comments, discussion, etc., please join the
   * Magpie mailing list:
   * magpierss-general@lists.sourceforge.net
   */
  
  /*======================================================================*\
      Function: parse_w3cdtf
      Purpose:  parse a W3CDTF date into unix epoch
  
      NOTE: http://www.w3.org/TR/NOTE-datetime
  \*======================================================================*/
  
  function parse_w3cdtf ( $date\_str\; )\; \{\; \#\; regex\; to\; match\; wc3dtf$pat = "/(\d{4})-(\d{2})-(\d{2})T(\d{2}):(\d{2})(:(\d{2}))?(?:([-+])(\d{2}):?(\d{2})|(Z))?/";
      
      if ( preg_match( $pat,$date_str, $match\; )\; )\; \{\; list($year, $month,$day, $hours,$minutes, $seconds)\; =\; array($match[1], $match[2],$match[3], $match[4],$match[5], $match[6]);\; \#\; calc\; epoch\; for\; current\; date\; assuming\; GMT$epoch = gmmktime( $hours,$minutes, $seconds,$month, $day,$year);
          
          $offset\; =\; 0;\; if\; ($match[10] == 'Z' ) {
              # zulu time, aka GMT
          }
          else {
              list( $tz\_mod,$tz_hour, $tz\_min\; )\; =\; array($match[8], $match[9],$match[10]);
              
              # zero out the variables
              if ( ! $tz\_hour\; )\; \{$tz_hour = 0; }
              if ( ! $tz\_min\; )\; \{$tz_min = 0; }
          
              $offset\_secs\; =\; (($tz_hour*60)+$tz\_min)*60;\; \#\; is\; timezone\; ahead\; of\; GMT?\; then\; subtract\; offset\; \#\; if\; ($tz_mod == '+' ) {
                  $offset\_secs\; =$offset_secs * -1;
              }
              
              $offset\; =$offset_secs; 
          }
          $epoch\; =$epoch + $offset;\; return$epoch;
      }
      else {
          return -1;
      }
  }
  
  ?>