Geeklog: system/classes/timezoneconfig.class.php@df55886043f2

     1 <?php

     3 /* Reminder: always indent with 4 spaces (no tabs). */

     4 // +---------------------------------------------------------------------------+

     5 // | Geeklog 1.6                                                               |

     6 // +---------------------------------------------------------------------------+

     7 // | timezoneconfig.class.php                                                  |

     8 // |                                                                           |

     9 // | Helper class for time zone handling                                       |

    10 // +---------------------------------------------------------------------------+

    11 // | Copyright (C) 2009 by the following authors:                              |

    12 // |                                                                           |

    13 // | Authors: Dirk Haun             - dirk AT haun-online DOT de               |

    14 // | based on earlier work by Oliver Spiesshofer, Yew Loong, and others        |

    15 // +---------------------------------------------------------------------------+

    16 // |                                                                           |

    17 // | This program is free software; you can redistribute it and/or             |

    18 // | modify it under the terms of the GNU General Public License               |

    19 // | as published by the Free Software Foundation; either version 2            |

    20 // | of the License, or (at your option) any later version.                    |

    21 // |                                                                           |

    22 // | This program is distributed in the hope that it will be useful,           |

    23 // | but WITHOUT ANY WARRANTY; without even the implied warranty of            |

    24 // | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the             |

    25 // | GNU General Public License for more details.                              |

    26 // |                                                                           |

    27 // | You should have received a copy of the GNU General Public License         |

    28 // | along with this program; if not, write to the Free Software Foundation,   |

    29 // | Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.           |

    30 // |                                                                           |

    31 // +---------------------------------------------------------------------------+

    33 /**

    34 * Geeklog Time Zone Config class

    35 *

    36 * A collection of static (for now) methods dealing with time zone handling.

    37 *

    38 * For the original "Timezone Hack" discussion, see

    39 * @link http://www.geeklog.net/forum/viewtopic.php?showtopic=21232

    40 *

    41 * @author Dirk Haun, dirk AT haun-online DOT de

    42 *

    43 */

    44 class TimeZoneConfig {

    46     /**

    47     * Set the system's timezone

    48     *

    49     * @param    string  $tz     timezone to set; use $_CONF['timezone'] if empty

    50     * @return   void

    51     * @static

    52     *

    53     */

    54     function setSystemTimeZone($tz = '')

    55     {

    56         global $_CONF;

    58         if (empty($tz) && !empty($_CONF['timezone'])) {

    59             $tz = $_CONF['timezone'];

    60         }

    62         if (! empty($tz)) {

    63             if (function_exists('date_default_timezone_set')) {

    64                 if (! @date_default_timezone_set($tz)) {

    65                     date_default_timezone_set('UTC');

    66                     COM_errorLog("Timezone '$tz' not valid - using 'UTC' instead", 1);

    67                 }

    68             } elseif (!ini_get('safe_mode') && function_exists('putenv')) {

    69                 // aka "Timezone Hack"

    70                 putenv('TZ=' . $tz);

    71             }

    72         } elseif (function_exists('date_default_timezone_get')) {

    73             // this is not ideal but will stop PHP 5.3.0ff from complaining ...

    74             date_default_timezone_set(@date_default_timezone_get());

    75         }

    76     }

    78     /**

    79     * Get the user's preferred timezone

    80     *

    81     * @return   string  name of the timezone

    82     * @static

    83     *

    84     */

    85     function getUserTimeZone()

    86     {

    87         global $_CONF, $_USER;

    89         if (! empty($_USER['tzid'])) {

    90             $timezone = $_USER['tzid'];

    91         } elseif (! empty($_CONF['timezone'])) {

    92             $timezone = $_CONF['timezone'];

    93         } else {

    94             require_once 'Date/TimeZone.php';

    96             $tz_obj = Date_TimeZone::getDefault();

    97             $timezone = $tz_obj->id;

    98         }

   100         return $timezone;

   101     }

   103     /**

   104     * Provide a dropdown menu of the available timezones

   105     *

   106     * @return   string  HTML for the dropdown

   107     * @static

   108     *

   109     */

   110     function getTimeZoneDropDown($selected = '', $attributes = array())

   111     {

   112         $timezones = TimeZoneConfig::listAvailableTimeZones();

   114         $selection = '<select';

   115         foreach ($attributes as $name => $value) {

   116             $selection .= sprintf(' %s="%s"', $name, $value);

   117         }

   118         $selection .= '>' . LB;

   120         foreach ($timezones as $tzid => $tzdisplay) {

   121             $selection .= '<option value="' . $tzid . '"';

   122             if (!empty($selected) && ($selected == $tzid)) {

   123                 $selection .= ' selected="selected"';

   124             }

   125             $selection .= ">$tzdisplay</option>" . LB;

   126         }

   127         $selection .= '</select>';

   129         return $selection;

   130     }

   132     /**

   133     * Provide a list of available timezones

   134     *

   135     * @return   array   array of (timezone-short-name, timezone-long-name) pairs

   136     * @static

   137     *

   138     */

   139     function listAvailableTimeZones()

   140     {

   141         $timezones = array();

   143         // use only timezones that contain one of these

   144         $useonly = array('Africa', 'America', 'Antarctica', 'Arctic', 'Asia',

   145                          'Atlantic', 'Australia', 'Europe', 'Indian', 'Pacific',

   146                          'UTC');

   148         // check if we can use the DateTimeZone class

   149         $useDateTimeZone = false;

   150         if (class_exists('DateTimeZone') && class_exists('ReflectionClass')) {

   151             $rc = new ReflectionClass('DateTimeZone');

   152             if ($rc->hasMethod('listAbbreviations')) {

   153                 $useDateTimeZone = true;

   154             }

   155         }

   157         if ($useDateTimeZone) {

   159             $T = DateTimeZone::listAbbreviations();

   160             foreach ($T as $tzid => $entries) {

   161                 $shortname = strtoupper($tzid);

   162                 foreach ($entries as $data) {

   163                     $tzcheck = explode('/', $data['timezone_id']);

   164                     if (! in_array($tzcheck[0], $useonly)) {

   165                         continue;

   166                     }

   168                     $hours = $data['offset'] / 3600;

   169                     $hours = ((int) ($hours * 100) / 100);

   170                     if ($hours > 0) {

   171                         $hours = "+$hours";

   172                     }

   174                     $tzcode = str_replace('_', ' ', $data['timezone_id']);

   175                     $tzcode = htmlspecialchars($tzcode);

   176                     $formattedTimezone = "$hours, $shortname ($tzcode)";

   177                     $timezones[$data['timezone_id']] = $formattedTimezone;

   178                 }

   179             }

   181         } else { // DateTimeZone not available - use PEAR Date class

   183             require_once 'Date/TimeZone.php';

   185             $T = $GLOBALS['_DATE_TIMEZONE_DATA'];

   187             foreach ($T as $tzid => $tDetails) {

   188                 $tzcheck = explode('/', $tzid);

   189                 if (! in_array($tzcheck[0], $useonly)) {

   190                     continue;

   191                 }

   192                 if (!empty($tzcheck[1]) &&

   193                         (strpos($tzcheck[1], 'Riyadh') === 0)) {

   194                     // these time zones are based on solar time and not widely

   195                     // supported - skip

   196                     continue;

   197                 }

   199                 $tzcode = str_replace('_', ' ', $tzid);

   200                 $tzcode = htmlspecialchars($tzcode);

   201                 $hours = $tDetails['offset'] / (3600 * 1000);

   202                 $hours = ((int) ($hours * 100) / 100);

   203                 if ($hours > 0) {

   204                     $hours = "+$hours";

   205                 }

   207                 $formattedTimezone = "$hours, {$tDetails['shortname']} ($tzcode)";

   208                 $timezones[$tzid] = $formattedTimezone;

   209             }

   211         }

   213         uasort($timezones, 'TimeZoneConfig::_sort_by_timezone');

   215         return $timezones;

   216     }

   218     /**

   219     * Helper method: Sort timezone entries

   220     *

   221     * @param    string  $tz1    first timezone

   222     * @param    string  $tz2    second timezone

   223     * @return   int             0: equal, <0: first<second, >0: first>second

   224     * @static

   225     * @access   private

   226     *

   227     */

   228     function _sort_by_timezone($tz1, $tz2)

   229     {

   230         $p1 = explode(',', $tz1);

   231         $p2 = explode(',', $tz2);

   233         // compare offsets

   234         $o1 = $p1[0];

   235         $o2 = $p2[0];

   236         if ($o1 != $o2) {

   237             return ($o1 < $o2 ? -1 : 1);

   238         }

   240         // drop offset, pop timezone name, then add it to the end again

   241         array_shift($p1);

   242         $tz1 = trim(implode(',', $p1));

   243         $p1 = explode(' ', $tz1);

   244         $x1 = array_shift($p1);

   245         $p1[] = $x1;

   246         $tz1 = implode(' ', $p1);

   248         array_shift($p2);

   249         $tz2 = trim(implode(',', $p2));

   250         $p2 = explode(' ', $tz2);

   251         $x2 = array_shift($p2);

   252         $p2[] = $x2;

   253         $tz2 = implode(' ', $p2);

   255         return strcmp($tz1, $tz2);

   256     }

   258 }

   260 ?>

author	Dirk Haun <dirk@haun-online.de>
	Sun, 20 Sep 2009 11:00:03 +0200
branch	HEAD
changeset 7428	df55886043f2
child 7429	01f95a3e4545
permissions	-rw-r--r--