text: /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
  /* ***** BEGIN LICENSE BLOCK *****
   * Version: MPL 1.1/GPL 2.0/LGPL 2.1
   *
   * The contents of this file are subject to the Mozilla Public License Version
   * 1.1 (the "License"); you may not use this file except in compliance with
   * the License. You may obtain a copy of the License at
   * http://www.mozilla.org/MPL/
   *
   * Software distributed under the License is distributed on an "AS IS" basis,
   * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
   * for the specific language governing rights and limitations under the
   * License.
   *
   * The Original Code is mozilla.org code.
   *
   * The Initial Developer of the Original Code is Robert Sayre.
   * Portions created by the Initial Developer are Copyright (C) 2006
   * the Initial Developer. All Rights Reserved.
   *
   * Contributor(s):
   * Flock Inc. <erwan@flock.com>
   *
   * Alternatively, the contents of this file may be used under the terms of
   * either the GNU General Public License Version 2 or later (the "GPL"), or
   * the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
   * in which case the provisions of the GPL or the LGPL are applicable instead
   * of those above. If you wish to allow use of your version of this file only
   * under the terms of either the GPL or the LGPL, and not to allow others to
   * use your version of this file under the terms of the MPL, indicate your
   * decision by deleting the provisions above and replace them with the notice
   * and other provisions required by the GPL or the LGPL. If you do not delete
   * the provisions above, a recipient may use your version of this file under
   * the terms of any one of the MPL, the GPL or the LGPL.
   *
   * ***** END LICENSE BLOCK ***** */
  
  const HOURS_TO_MINUTES = 60;
  const MINUTES_TO_SECONDS = 60;
  const SECONDS_TO_MILLISECONDS = 1000;
  const MINUTES_TO_MILLISECONDS = MINUTES_TO_SECONDS * SECONDS_TO_MILLISECONDS;
  const HOURS_TO_MILLISECONDS = HOURS_TO_MINUTES * MINUTES_TO_MILLISECONDS;
  
  var EXPORTED_SYMBOLS = ["ISO8601DateUtils"];
  
  debug("*** loading ISO8601DateUtils\n");
  
  var ISO8601DateUtils = {
  
    /**
    * XXX Thunderbird's W3C-DTF function
    *
    * Converts a W3C-DTF (subset of ISO 8601) date string to a Javascript
    * date object. W3C-DTF is described in this note:
    * http://www.w3.org/TR/NOTE-datetime IETF is obtained via the Date
    * object's toUTCString() method.  The object's toString() method is
    * insufficient because it spells out timezones on Win32
    * (f.e. "Pacific Standard Time" instead of "PST"), which Mail doesn't
    * grok.  For info, see
    * http://lxr.mozilla.org/mozilla/source/js/src/jsdate.c#1526.
    */
    parse: function ISO8601_parse(aDateString) {
      var dateString = aDateString;
      if (!dateString.match('-')) {
        // Workaround for server sending
        // dates such as: 20030530T11:18:50-08:00
        // instead of: 2003-05-30T11:18:50-08:00
        var year = dateString.slice(0, 4);
        var month = dateString.slice(4, 6);
        var rest = dateString.slice(6, dateString.length);
        dateString = year + "-" + month + "-" + rest;
      }
  
      var parts = dateString.match(/(\d{4})(-(\d{2,3}))?(-(\d{2}))?(T(\d{2}):(\d{2})(:(\d{2})(\.(\d+))?)?(Z|([+-])(\d{2}):(\d{2}))?)?/);
  
      // Here's an example of a W3C-DTF date string and what .match returns for it.
      //
      // date: 2003-05-30T11:18:50.345-08:00
      // date.match returns array values:
      //
      //   0: 2003-05-30T11:18:50-08:00,
      //   1: 2003,
      //   2: -05,
      //   3: 05,
      //   4: -30,
      //   5: 30,
      //   6: T11:18:50-08:00,
      //   7: 11,
      //   8: 18,
      //   9: :50,
      //   10: 50,
      //   11: .345,
      //   12: 345,
      //   13: -08:00,
      //   14: -,
      //   15: 08,
      //   16: 00
  
      // Create a Date object from the date parts.  Note that the Date
      // object apparently can't deal with empty string parameters in lieu
      // of numbers, so optional values (like hours, minutes, seconds, and
      // milliseconds) must be forced to be numbers.
      var date = new Date(parts[1], parts[3] - 1, parts[5], parts[7] || 0,
        parts[8] || 0, parts[10] || 0, parts[12] || 0);
  
      // We now have a value that the Date object thinks is in the local
      // timezone but which actually represents the date/time in the
      // remote timezone (f.e. the value was "10:00 EST", and we have
      // converted it to "10:00 PST" instead of "07:00 PST").  We need to
      // correct that.  To do so, we're going to add the offset between
      // the remote timezone and UTC (to convert the value to UTC), then
      // add the offset between UTC and the local timezone //(to convert
      // the value to the local timezone).
  
      // Ironically, W3C-DTF gives us the offset between UTC and the
      // remote timezone rather than the other way around, while the
      // getTimezoneOffset() method of a Date object gives us the offset
      // between the local timezone and UTC rather than the other way
      // around.  Both of these are the additive inverse (i.e. -x for x)
      // of what we want, so we have to invert them to use them by
      // multipying by -1 (f.e. if "the offset between UTC and the remote
      // timezone" is -5 hours, then "the offset between the remote
      // timezone and UTC" is -5*-1 = 5 hours).
  
      // Note that if the timezone portion of the date/time string is
      // absent (which violates W3C-DTF, although ISO 8601 allows it), we
      // assume the value to be in UTC.
  
      // The offset between the remote timezone and UTC in milliseconds.
      var remoteToUTCOffset = 0;
      if (parts[13] && parts[13] != "Z") {
        var direction = (parts[14] == "+" ? 1 : -1);
        if (parts[15])
          remoteToUTCOffset += direction * parts[15] * HOURS_TO_MILLISECONDS;
        if (parts[16])
          remoteToUTCOffset += direction * parts[16] * MINUTES_TO_MILLISECONDS;
      }
      remoteToUTCOffset = remoteToUTCOffset * -1; // invert it
  
      // The offset between UTC and the local timezone in milliseconds.
      var UTCToLocalOffset = date.getTimezoneOffset() * MINUTES_TO_MILLISECONDS;
      UTCToLocalOffset = UTCToLocalOffset * -1; // invert it
      date.setTime(date.getTime() + remoteToUTCOffset + UTCToLocalOffset);
  
      return date;
    },
  
    create: function ISO8601_create(aDate) {
      function zeropad (s, l) {
        s = s.toString(); // force it to a string
        while (s.length < l) {
          s = '0' + s;
        }
        return s;
      }
  
      var myDate;
      // if d is a number, turn it into a date
      if (typeof aDate == 'number') {
        myDate = new Date()
        myDate.setTime(aDate);
      } else {
        myDate = aDate;
      }
  
      // YYYY-MM-DDThh:mm:ssZ
      var result = zeropad(myDate.getUTCFullYear (), 4) +
                   zeropad(myDate.getUTCMonth () + 1, 2) +
                   zeropad(myDate.getUTCDate (), 2) + 'T' +
                   zeropad(myDate.getUTCHours (), 2) + ':' +
                   zeropad(myDate.getUTCMinutes (), 2) + ':' +
                   zeropad(myDate.getUTCSeconds (), 2) + 'Z';
  
      return result;
    }
  }
  