Geeklog: system/classes/timezoneconfig.class.php@ecdf072e268e

     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         static $system_timezone = '';

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

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

    62         }

    64         if (! empty($tz)) {

    65             if ($tz != $system_timezone) {

    66                 if (function_exists('date_default_timezone_set')) {

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

    68                         date_default_timezone_set('UTC');

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

    70                         $system_timezone = 'UTC';

    71                     } else {

    72                         $system_timezone = $tz;

    73                     }

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

    75                     // aka "Timezone Hack"

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

    77                     $system_timezone = $tz;

    78                 }

    79             }

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

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

    82             $system_timezone = @date_default_timezone_get();

    83             date_default_timezone_set($system_timezone);

    84         }

    85     }

    87     /**

    88     * Get the user's preferred timezone

    89     *

    90     * @return   string  name of the timezone

    91     * @static

    92     *

    93     */

    94     function getUserTimeZone()

    95     {

    96         global $_CONF, $_USER;

    98         // handle like the theme cookie, i.e. use if user is not logged in

    99         if (isset($_COOKIE[$_CONF['cookie_tzid']]) && empty($_USER['tzid'])) {

   100             $_USER['tzid'] = $_COOKIE[$_CONF['cookie_tzid']];

   101         }

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

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

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

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

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

   108             $timezone = @date_default_timezone_get();

   109         } else {

   110             require_once 'Date/TimeZone.php';

   112             $tz_obj = Date_TimeZone::getDefault();

   113             $timezone = $tz_obj->id;

   114         }

   116         return $timezone;

   117     }

   119     /**

   120     * Provide a dropdown menu of the available timezones

   121     *

   122     * @return   string  HTML for the dropdown

   123     * @static

   124     *

   125     */

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

   127     {

   128         $timezones = TimeZoneConfig::listAvailableTimeZones();

   130         $selection = '<select';

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

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

   133         }

   134         $selection .= '>' . LB;

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

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

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

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

   140             }

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

   142         }

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

   145         return $selection;

   146     }

   148     /**

   149     * Provide a list of available timezones

   150     *

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

   152     * @static

   153     *

   154     */

   155     function listAvailableTimeZones()

   156     {

   157         $timezones = array();

   159         // use only timezones that contain one of these

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

   161                          'Atlantic', 'Australia', 'Europe', 'Indian', 'Pacific',

   162                          'UTC');

   164         // check if we can use the DateTimeZone class

   165         $useDateTimeZone = false;

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

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

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

   169                 $useDateTimeZone = true;

   170             }

   171         }

   173         if ($useDateTimeZone) {

   175             $T = DateTimeZone::listAbbreviations();

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

   177                 $shortname = strtoupper($tzid);

   178                 foreach ($entries as $data) {

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

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

   181                         continue;

   182                     }

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

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

   186                     if ($hours > 0) {

   187                         $hours = "+$hours";

   188                     }

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

   191                     $tzcode = htmlspecialchars($tzcode);

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

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

   194                 }

   195             }

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

   199             require_once 'Date/TimeZone.php';

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

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

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

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

   206                     continue;

   207                 }

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

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

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

   211                     // supported - skip

   212                     continue;

   213                 }

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

   216                 $tzcode = htmlspecialchars($tzcode);

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

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

   219                 if ($hours > 0) {

   220                     $hours = "+$hours";

   221                 }

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

   224                 $timezones[$tzid] = $formattedTimezone;

   225             }

   227         }

   229         uasort($timezones, array('TimeZoneConfig', '_sort_by_timezone'));

   231         return $timezones;

   232     }

   234     /**

   235     * Helper method: Sort timezone entries

   236     *

   237     * @param    string  $tz1    first timezone

   238     * @param    string  $tz2    second timezone

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

   240     * @static

   241     * @access   private

   242     *

   243     */

   244     function _sort_by_timezone($tz1, $tz2)

   245     {

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

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

   249         // compare offsets

   250         $o1 = $p1[0];

   251         $o2 = $p2[0];

   252         if ($o1 != $o2) {

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

   254         }

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

   257         array_shift($p1);

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

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

   260         $x1 = array_shift($p1);

   261         $p1[] = $x1;

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

   264         array_shift($p2);

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

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

   267         $x2 = array_shift($p2);

   268         $p2[] = $x2;

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

   271         return strcmp($tz1, $tz2);

   272     }

   274 }

   276 ?>

author	Dirk Haun <dirk@haun-online.de>
	Sun, 20 Sep 2009 17:06:57 +0200
branch	HEAD
changeset 7431	ecdf072e268e
parent 7430	a053d9023368
child 7432	3125f1336c8c
permissions	-rw-r--r--