includes/specials/SpecialMyLanguage.php

   1 <?php
   2 /**
   3  * Implements Special:MyLanguage
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation; either version 2 of the License, or
   8  * (at your option) any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License along
  16  * with this program; if not, write to the Free Software Foundation, Inc.,
  17  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  18  * http://www.gnu.org/copyleft/gpl.html
  19  *
  20  * @file
  21  * @author Niklas Laxström
  22  * @author Siebrand Mazeland
  23  * @copyright Copyright © 2010-2013 Niklas Laxström, Siebrand Mazeland
  24  */
  25
  26 use MediaWiki\MediaWikiServices;
  27
  28 /**
  29  * Unlisted special page just to redirect the user to the translated version of
  30  * a page, if it exists.
  31  *
  32  * Usage: [[Special:MyLanguage/Page name|link text]]
  33  *
  34  * @since 1.24
  35  * @ingroup SpecialPage
  36  */
  37 class SpecialMyLanguage extends RedirectSpecialArticle {
  38         public function __construct() {
  39                 parent::__construct( 'MyLanguage' );
  40         }
  41
  42         /**
  43          * If the special page is a redirect, then get the Title object it redirects to.
  44          * False otherwise.
  45          *
  46          * @param string|null $subpage
  47          * @return Title
  48          */
  49         public function getRedirect( $subpage ) {
  50                 $title = $this->findTitle( $subpage );
  51                 // Go to the main page if given invalid title.
  52                 if ( !$title ) {
  53                         $title = Title::newMainPage();
  54                 }
  55                 return $title;
  56         }
  57
  58         /**
  59          * Assuming the user's interface language is fi. Given input Page, it
  60          * returns Page/fi if it exists, otherwise Page. Given input Page/de,
  61          * it returns Page/fi if it exists, otherwise Page/de if it exists,
  62          * otherwise Page.
  63          *
  64          * @param string|null $subpage
  65          * @return Title|null
  66          */
  67         public function findTitle( $subpage ) {
  68                 // base = title without language code suffix
  69                 // provided = the title as it was given
  70                 $base = $provided = null;
  71                 if ( $subpage !== null ) {
  72                         $provided = Title::newFromText( $subpage );
  73                         $base = $provided;
  74
  75                         if ( $provided && strpos( $subpage, '/' ) !== false ) {
  76                                 $pos = strrpos( $subpage, '/' );
  77                                 $basepage = substr( $subpage, 0, $pos );
  78                                 $code = substr( $subpage, $pos + 1 );
  79                                 if ( strlen( $code ) && Language::isKnownLanguageTag( $code ) ) {
  80                                         $base = Title::newFromText( $basepage );
  81                                 }
  82                         }
  83                 }
  84
  85                 if ( !$base ) {
  86                         // No subpage provided or base page does not exist
  87                         return null;
  88                 }
  89
  90                 if ( $base->isRedirect() ) {
  91                         $page = new WikiPage( $base );
  92                         $base = $page->getRedirectTarget();
  93                 }
  94
  95                 $uiLang = $this->getLanguage();
  96                 $contLang = MediaWikiServices::getInstance()->getContentLanguage();
  97
  98                 if ( $uiLang->equals( $contLang ) ) {
  99                         // Short circuit when the current UI language is the
 100                         // wiki's default language to avoid unnecessary page lookups.
 101                         return $base;
 102                 }
 103
 104                 // Check for a subpage in current UI language
 105                 $proposed = $base->getSubpage( $uiLang->getCode() );
 106                 if ( $proposed && $proposed->exists() ) {
 107                         return $proposed;
 108                 }
 109
 110                 if ( $provided !== $base && $provided->exists() ) {
 111                         // Explicit language code given and the page exists
 112                         return $provided;
 113                 }
 114
 115                 // Check for fallback languages specified by the UI language
 116                 $possibilities = $uiLang->getFallbackLanguages();
 117                 foreach ( $possibilities as $lang ) {
 118                         if ( $lang !== $contLang->getCode() ) {
 119                                 $proposed = $base->getSubpage( $lang );
 120                                 if ( $proposed && $proposed->exists() ) {
 121                                         return $proposed;
 122                                 }
 123                         }
 124                 }
 125
 126                 // When all else has failed, return the base page
 127                 return $base;
 128         }
 129
 130         /**
 131          * Target can identify a specific user's language preference.
 132          *
 133          * @see T109724
 134          * @since 1.27
 135          * @return bool
 136          */
 137         public function personallyIdentifiableTarget() {
 138                 return true;
 139         }
 140 }