Geeklog: system/classes/timezoneconfig.class.php@3125f1336c8c

     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     * Set the user's preferred timezone

    89     *

    90     * Note that does nothing if $_CONF['timezone'] is empty, i.e. if no

    91     * system timezone is defined, we don't set a user timezone either.

    92     *

    93     * @return void

    94     * @static

    95     *

    96     */

    97     function setUserTimeZone()

    98     {

    99         global $_CONF;

   101         if (! empty($_CONF['timezone'])) {

   102             $tz = TimeZoneConfig::getUserTimeZone();

   103             if (! empty($tz)) {

   104                 TimeZoneConfig::setSystemTimeZone($tz);

   105             }

   106         }

   107     }

   109     /**

   110     * Get the user's preferred timezone

   111     *

   112     * @return   string  name of the timezone

   113     * @static

   114     *

   115     */

   116     function getUserTimeZone()

   117     {

   118         global $_CONF, $_USER;

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

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

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

   123         }

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

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

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

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

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

   130             $timezone = @date_default_timezone_get();

   131         } else {

   132             require_once 'Date/TimeZone.php';

   134             $tz_obj = Date_TimeZone::getDefault();

   135             $timezone = $tz_obj->id;

   136         }

   138         return $timezone;

   139     }

   141     /**

   142     * Provide a dropdown menu of the available timezones

   143     *

   144     * @return   string  HTML for the dropdown

   145     * @static

   146     *

   147     */

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

   149     {

   150         $timezones = TimeZoneConfig::listAvailableTimeZones();

   152         $selection = '<select';

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

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

   155         }

   156         $selection .= '>' . LB;

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

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

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

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

   162             }

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

   164         }

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

   167         return $selection;

   168     }

   170     /**

   171     * Provide a list of available timezones

   172     *

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

   174     * @static

   175     *

   176     */

   177     function listAvailableTimeZones()

   178     {

   179         $timezones = array();

   181         // use only timezones that contain one of these

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

   183                          'Atlantic', 'Australia', 'Europe', 'Indian', 'Pacific',

   184                          'UTC');

   186         // check if we can use the DateTimeZone class

   187         $useDateTimeZone = false;

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

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

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

   191                 $useDateTimeZone = true;

   192             }

   193         }

   195         if ($useDateTimeZone) {

   197             $T = DateTimeZone::listAbbreviations();

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

   199                 $shortname = strtoupper($tzid);

   200                 foreach ($entries as $data) {

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

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

   203                         continue;

   204                     }

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

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

   208                     if ($hours > 0) {

   209                         $hours = "+$hours";

   210                     }

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

   213                     $tzcode = htmlspecialchars($tzcode);

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

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

   216                 }

   217             }

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

   221             require_once 'Date/TimeZone.php';

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

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

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

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

   228                     continue;

   229                 }

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

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

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

   233                     // supported - skip

   234                     continue;

   235                 }

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

   238                 $tzcode = htmlspecialchars($tzcode);

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

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

   241                 if ($hours > 0) {

   242                     $hours = "+$hours";

   243                 }

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

   246                 $timezones[$tzid] = $formattedTimezone;

   247             }

   249         }

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

   253         return $timezones;

   254     }

   256     /**

   257     * Helper method: Sort timezone entries

   258     *

   259     * @param    string  $tz1    first timezone

   260     * @param    string  $tz2    second timezone

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

   262     * @static

   263     * @access   private

   264     *

   265     */

   266     function _sort_by_timezone($tz1, $tz2)

   267     {

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

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

   271         // compare offsets

   272         $o1 = $p1[0];

   273         $o2 = $p2[0];

   274         if ($o1 != $o2) {

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

   276         }

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

   279         array_shift($p1);

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

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

   282         $x1 = array_shift($p1);

   283         $p1[] = $x1;

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

   286         array_shift($p2);

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

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

   289         $x2 = array_shift($p2);

   290         $p2[] = $x2;

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

   293         return strcmp($tz1, $tz2);

   294     }

   296 }

   298 ?>

author	Dirk Haun <dirk@haun-online.de>
	Sun, 20 Sep 2009 19:07:20 +0200
branch	HEAD
changeset 7432	3125f1336c8c
parent 7431	ecdf072e268e
child 7444	252d8d24012d
permissions	-rw-r--r--