phpjs/workbench/datetime/date_parse_from_format.js

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function date_parse_from_format(format, dateArg) {
  // http://kevin.vanzonneveld.net
  // +   original by: Brett Zamir (http://brett-zamir.me)
  // -    depends on: strtotime
  // -    depends on: date
  // -    depends on: date_parse
  // *     example 1: date_parse_from_format('j.n.Y H:iP', '6.1.2009 13:00+01:00');
  // *     returns 1: {year : 2006, month: 12, day: 12, hour: 10, minute: 0, second: 0, fraction: 0.5, warning_count: 0, warnings: [], error_count: 0, errors: [], is_localtime: false, zone_type: 1, zone: -60, is_dst:false}

  var newtime = 0, retObj = {};

  var _dst = function(t) {
    // Calculate Daylight Saving Time (derived from gettimeofday() code)
    var dst = 0;
    var jan1 = new Date(t.getFullYear(), 0, 1, 0, 0, 0, 0);  // jan 1st
    var june1 = new Date(t.getFullYear(), 6, 1, 0, 0, 0, 0); // june 1st
    var temp = jan1.toUTCString();
    var jan2 = new Date(temp.slice(0, temp.lastIndexOf(' ') - 1));
    temp = june1.toUTCString();
    var june2 = new Date(temp.slice(0, temp.lastIndexOf(' ') - 1));
    var std_time_offset = (jan1 - jan2) / (1000 * 60 * 60);
    var daylight_time_offset = (june1 - june2) / (1000 * 60 * 60);

    if (std_time_offset === daylight_time_offset) {
      dst = false; // daylight savings time is NOT observed
    }
    else {
      // positive is southern, negative is northern hemisphere
      var hemisphere = std_time_offset - daylight_time_offset;
      if (hemisphere >= 0) {
        std_time_offset = daylight_time_offset;
      }
      dst = true; // daylight savings time is observed
    }
    return dst;
  };

  try {
    newtime = 0; // fix: needs to use format, dateArg to return a time
    retObj = this.date_parse(newtime);
  }
  catch (e) {
    return false; // Presumably returns false, as with date_parse()
  }

  retObj.is_dst = _dst(newtime);

  // Fix: need to add the following as well
  //zone_type: TIMELIB_ZONETYPE_OFFSET 1, TIMELIB_ZONETYPE_ABBR   2, TIMELIB_ZONETYPE_ID     3
  //zone: -60

  return retObj;
}