includes/CategoryPage.php

   1 <?php
   2 /**
   3  * Class for viewing MediaWiki category description pages.
   4  * Modelled after ImagePage.php.
   5  *
   6  * @file
   7  */
   8
   9 if ( !defined( 'MEDIAWIKI' ) )
  10         die( 1 );
  11
  12 /**
  13  * Special handling for category description pages, showing pages,
  14  * subcategories and file that belong to the category
  15  */
  16 class CategoryPage extends Article {
  17         # Subclasses can change this to override the viewer class.
  18         protected $mCategoryViewerClass = 'CategoryViewer';
  19
  20         protected function newPage( Title $title ) {
  21                 // Overload mPage with a category-specific page
  22                 return new WikiCategoryPage( $title );
  23         }
  24
  25         /**
  26          * Constructor from a page id
  27          * @param $id Int article ID to load
  28          */
  29         public static function newFromID( $id ) {
  30                 $t = Title::newFromID( $id );
  31                 # @todo FIXME: Doesn't inherit right
  32                 return $t == null ? null : new self( $t );
  33                 # return $t == null ? null : new static( $t ); // PHP 5.3
  34         }
  35
  36         function view() {
  37                 $request = $this->getContext()->getRequest();
  38                 $diff = $request->getVal( 'diff' );
  39                 $diffOnly = $request->getBool( 'diffonly',
  40                         $this->getContext()->getUser()->getOption( 'diffonly' ) );
  41
  42                 if ( isset( $diff ) && $diffOnly ) {
  43                         return parent::view();
  44                 }
  45
  46                 if ( !wfRunHooks( 'CategoryPageView', array( &$this ) ) ) {
  47                         return;
  48                 }
  49
  50                 if ( NS_CATEGORY == $this->mTitle->getNamespace() ) {
  51                         $this->openShowCategory();
  52                 }
  53
  54                 parent::view();
  55
  56                 if ( NS_CATEGORY == $this->mTitle->getNamespace() ) {
  57                         $this->closeShowCategory();
  58                 }
  59         }
  60
  61         function openShowCategory() {
  62                 # For overloading
  63         }
  64
  65         function closeShowCategory() {
  66                 // Use these as defaults for back compat --catrope
  67                 $request = $this->getContext()->getRequest();
  68                 $oldFrom = $request->getVal( 'from' );
  69                 $oldUntil = $request->getVal( 'until' );
  70
  71                 $reqArray = $request->getValues();
  72
  73                 $from = $until = array();
  74                 foreach ( array( 'page', 'subcat', 'file' ) as $type ) {
  75                         $from[$type] = $request->getVal( "{$type}from", $oldFrom );
  76                         $until[$type] = $request->getVal( "{$type}until", $oldUntil );
  77
  78                         // Do not want old-style from/until propagating in nav links.
  79                         if ( !isset( $reqArray["{$type}from"] ) && isset( $reqArray["from"] ) ) {
  80                                 $reqArray["{$type}from"] = $reqArray["from"];
  81                         }
  82                         if ( !isset( $reqArray["{$type}to"] ) && isset( $reqArray["to"] ) ) {
  83                                 $reqArray["{$type}to"] = $reqArray["to"];
  84                         }
  85                 }
  86
  87                 unset( $reqArray["from"] );
  88                 unset( $reqArray["to"] );
  89
  90                 $viewer = new $this->mCategoryViewerClass( $this->mTitle, $this->getContext(), $from, $until, $reqArray );
  91                 $this->getContext()->getOutput()->addHTML( $viewer->getHTML() );
  92         }
  93 }
  94
  95 class CategoryViewer {
  96         var $limit, $from, $until,
  97                 $articles, $articles_start_char,
  98                 $children, $children_start_char,
  99                 $showGallery, $imgsNoGalley,
 100                 $imgsNoGallery_start_char,
 101                 $imgsNoGallery;
 102
 103         /**
 104          * @var
 105          */
 106         var $nextPage;
 107
 108         /**
 109          * @var Array
 110          */
 111         var $flip;
 112
 113         /**
 114          * @var Title
 115          */
 116         var $title;
 117
 118         /**
 119          * @var Collation
 120          */
 121         var $collation;
 122
 123         /**
 124          * @var ImageGallery
 125          */
 126         var $gallery;
 127
 128         /**
 129          * Category object for this page
 130          * @var Category
 131          */
 132         private $cat;
 133
 134         /**
 135          * The original query array, to be used in generating paging links.
 136          * @var array
 137          */
 138         private $query;
 139
 140         /**
 141          * Context object
 142          * @var IContextSource
 143          */
 144         protected $context;
 145
 146         /**
 147          * Constructor
 148          *
 149          * @since 1.19 $context is a second, required parameter
 150          * @param $title Title
 151          * @param $context IContextSource
 152          * @param $from String
 153          * @param $until String
 154          * @param $query Array
 155          */
 156         function __construct( $title, IContextSource $context, $from = '', $until = '', $query = array() ) {
 157                 global $wgCategoryPagingLimit;
 158                 $this->title = $title;
 159                 $this->context = $context;
 160                 $this->from = $from;
 161                 $this->until = $until;
 162                 $this->limit = $wgCategoryPagingLimit;
 163                 $this->cat = Category::newFromTitle( $title );
 164                 $this->query = $query;
 165                 $this->collation = Collation::singleton();
 166                 unset( $this->query['title'] );
 167         }
 168
 169         /**
 170          * Format the category data list.
 171          *
 172          * @return string HTML output
 173          */
 174         public function getHTML() {
 175                 global $wgCategoryMagicGallery;
 176                 wfProfileIn( __METHOD__ );
 177
 178                 $this->showGallery = $wgCategoryMagicGallery && !$this->context->getOutput()->mNoGallery;
 179
 180                 $this->clearCategoryState();
 181                 $this->doCategoryQuery();
 182                 $this->finaliseCategoryState();
 183
 184                 $r = $this->getSubcategorySection() .
 185                         $this->getPagesSection() .
 186                         $this->getImageSection();
 187
 188                 if ( $r == '' ) {
 189                         // If there is no category content to display, only
 190                         // show the top part of the navigation links.
 191                         // @todo FIXME: Cannot be completely suppressed because it
 192                         //        is unknown if 'until' or 'from' makes this
 193                         //        give 0 results.
 194                         $r = $r . $this->getCategoryTop();
 195                 } else {
 196                         $r = $this->getCategoryTop() .
 197                                 $r .
 198                                 $this->getCategoryBottom();
 199                 }
 200
 201                 // Give a proper message if category is empty
 202                 if ( $r == '' ) {
 203                         $r = wfMsgExt( 'category-empty', array( 'parse' ) );
 204                 }
 205
 206                 $lang = $this->getLang();
 207                 $langAttribs = array( 'lang' => $lang->getCode(), 'dir' => $lang->getDir() );
 208                 # put a div around the headings which are in the user language
 209                 $r = Html::openElement( 'div', $langAttribs ) . $r . '</div>';
 210
 211                 wfProfileOut( __METHOD__ );
 212                 return $r;
 213         }
 214
 215         function clearCategoryState() {
 216                 $this->articles = array();
 217                 $this->articles_start_char = array();
 218                 $this->children = array();
 219                 $this->children_start_char = array();
 220                 if ( $this->showGallery ) {
 221                         $this->gallery = new ImageGallery();
 222                         $this->gallery->setHideBadImages();
 223                 } else {
 224                         $this->imgsNoGallery = array();
 225                         $this->imgsNoGallery_start_char = array();
 226                 }
 227         }
 228
 229         /**
 230          * Add a subcategory to the internal lists, using a Category object
 231          */
 232         function addSubcategoryObject( Category $cat, $sortkey, $pageLength ) {
 233                 // Subcategory; strip the 'Category' namespace from the link text.
 234                 $title = $cat->getTitle();
 235
 236                 $link = Linker::link( $title, htmlspecialchars( $title->getText() ) );
 237                 if ( $title->isRedirect() ) {
 238                         // This didn't used to add redirect-in-category, but might
 239                         // as well be consistent with the rest of the sections
 240                         // on a category page.
 241                         $link = '<span class="redirect-in-category">' . $link . '</span>';
 242                 }
 243                 $this->children[] = $link;
 244
 245                 $this->children_start_char[] =
 246                         $this->getSubcategorySortChar( $cat->getTitle(), $sortkey );
 247         }
 248
 249         /**
 250          * Add a subcategory to the internal lists, using a title object
 251          * @deprecated since 1.17 kept for compatibility, please use addSubcategoryObject instead
 252          */
 253         function addSubcategory( Title $title, $sortkey, $pageLength ) {
 254                 $this->addSubcategoryObject( Category::newFromTitle( $title ), $sortkey, $pageLength );
 255         }
 256
 257         /**
 258         * Get the character to be used for sorting subcategories.
 259         * If there's a link from Category:A to Category:B, the sortkey of the resulting
 260         * entry in the categorylinks table is Category:A, not A, which it SHOULD be.
 261         * Workaround: If sortkey == "Category:".$title, than use $title for sorting,
 262         * else use sortkey...
 263         *
 264         * @param Title $title
 265         * @param string $sortkey The human-readable sortkey (before transforming to icu or whatever).
 266         */
 267         function getSubcategorySortChar( $title, $sortkey ) {
 268                 if ( $title->getPrefixedText() == $sortkey ) {
 269                         $word = $title->getDBkey();
 270                 } else {
 271                         $word = $sortkey;
 272                 }
 273
 274                 $firstChar = $this->collation->getFirstLetter( $word );
 275
 276                 return $this->getLang()->convert( $firstChar );
 277         }
 278
 279         /**
 280          * Add a page in the image namespace
 281          */
 282         function addImage( Title $title, $sortkey, $pageLength, $isRedirect = false ) {
 283                 if ( $this->showGallery ) {
 284                         $flip = $this->flip['file'];
 285                         if ( $flip ) {
 286                                 $this->gallery->insert( $title );
 287                         } else {
 288                                 $this->gallery->add( $title );
 289                         }
 290                 } else {
 291                         $link = Linker::link( $title );
 292                         if ( $isRedirect ) {
 293                                 // This seems kind of pointless given 'mw-redirect' class,
 294                                 // but keeping for back-compatibility with user css.
 295                                 $link = '<span class="redirect-in-category">' . $link . '</span>';
 296                         }
 297                         $this->imgsNoGallery[] = $link;
 298
 299                         $this->imgsNoGallery_start_char[] = $this->getLang()->convert(
 300                                 $this->collation->getFirstLetter( $sortkey ) );
 301                 }
 302         }
 303
 304         /**
 305          * Add a miscellaneous page
 306          */
 307         function addPage( $title, $sortkey, $pageLength, $isRedirect = false ) {
 308                 $link = Linker::link( $title );
 309                 if ( $isRedirect ) {
 310                         // This seems kind of pointless given 'mw-redirect' class,
 311                         // but keeping for back-compatiability with user css.
 312                         $link = '<span class="redirect-in-category">' . $link . '</span>';
 313                 }
 314                 $this->articles[] = $link;
 315
 316                 $this->articles_start_char[] = $this->getLang()->convert->convert(
 317                         $this->collation->getFirstLetter( $sortkey ) );
 318         }
 319
 320         function finaliseCategoryState() {
 321                 if ( $this->flip['subcat'] ) {
 322                         $this->children            = array_reverse( $this->children );
 323                         $this->children_start_char = array_reverse( $this->children_start_char );
 324                 }
 325                 if ( $this->flip['page'] ) {
 326                         $this->articles            = array_reverse( $this->articles );
 327                         $this->articles_start_char = array_reverse( $this->articles_start_char );
 328                 }
 329                 if ( !$this->showGallery && $this->flip['file'] ) {
 330                         $this->imgsNoGallery            = array_reverse( $this->imgsNoGallery );
 331                         $this->imgsNoGallery_start_char = array_reverse( $this->imgsNoGallery_start_char );
 332                 }
 333         }
 334
 335         function doCategoryQuery() {
 336                 $dbr = wfGetDB( DB_SLAVE, 'category' );
 337
 338                 $this->nextPage = array(
 339                         'page' => null,
 340                         'subcat' => null,
 341                         'file' => null,
 342                 );
 343                 $this->flip = array( 'page' => false, 'subcat' => false, 'file' => false );
 344
 345                 foreach ( array( 'page', 'subcat', 'file' ) as $type ) {
 346                         # Get the sortkeys for start/end, if applicable.  Note that if
 347                         # the collation in the database differs from the one
 348                         # set in $wgCategoryCollation, pagination might go totally haywire.
 349                         $extraConds = array( 'cl_type' => $type );
 350                         if ( $this->from[$type] !== null ) {
 351                                 $extraConds[] = 'cl_sortkey >= '
 352                                         . $dbr->addQuotes( $this->collation->getSortKey( $this->from[$type] ) );
 353                         } elseif ( $this->until[$type] !== null ) {
 354                                 $extraConds[] = 'cl_sortkey < '
 355                                         . $dbr->addQuotes( $this->collation->getSortKey( $this->until[$type] ) );
 356                                 $this->flip[$type] = true;
 357                         }
 358
 359                         $res = $dbr->select(
 360                                 array( 'page', 'categorylinks', 'category' ),
 361                                 array( 'page_id', 'page_title', 'page_namespace', 'page_len',
 362                                         'page_is_redirect', 'cl_sortkey', 'cat_id', 'cat_title',
 363                                         'cat_subcats', 'cat_pages', 'cat_files',
 364                                         'cl_sortkey_prefix', 'cl_collation' ),
 365                                 array_merge( array( 'cl_to' => $this->title->getDBkey() ),  $extraConds ),
 366                                 __METHOD__,
 367                                 array(
 368                                         'USE INDEX' => array( 'categorylinks' => 'cl_sortkey' ),
 369                                         'LIMIT' => $this->limit + 1,
 370                                         'ORDER BY' => $this->flip[$type] ? 'cl_sortkey DESC' : 'cl_sortkey',
 371                                 ),
 372                                 array(
 373                                         'categorylinks'  => array( 'INNER JOIN', 'cl_from = page_id' ),
 374                                         'category' => array( 'LEFT JOIN', 'cat_title = page_title AND page_namespace = ' . NS_CATEGORY )
 375                                 )
 376                         );
 377
 378                         $count = 0;
 379                         foreach ( $res as $row ) {
 380                                 $title = Title::newFromRow( $row );
 381                                 if ( $row->cl_collation === '' ) {
 382                                         // Hack to make sure that while updating from 1.16 schema
 383                                         // and db is inconsistent, that the sky doesn't fall.
 384                                         // See r83544. Could perhaps be removed in a couple decades...
 385                                         $humanSortkey = $row->cl_sortkey;
 386                                 } else {
 387                                         $humanSortkey = $title->getCategorySortkey( $row->cl_sortkey_prefix );
 388                                 }
 389
 390                                 if ( ++$count > $this->limit ) {
 391                                         # We've reached the one extra which shows that there
 392                                         # are additional pages to be had. Stop here...
 393                                         $this->nextPage[$type] = $humanSortkey;
 394                                         break;
 395                                 }
 396
 397                                 if ( $title->getNamespace() == NS_CATEGORY ) {
 398                                         $cat = Category::newFromRow( $row, $title );
 399                                         $this->addSubcategoryObject( $cat, $humanSortkey, $row->page_len );
 400                                 } elseif ( $title->getNamespace() == NS_FILE ) {
 401                                         $this->addImage( $title, $humanSortkey, $row->page_len, $row->page_is_redirect );
 402                                 } else {
 403                                         $this->addPage( $title, $humanSortkey, $row->page_len, $row->page_is_redirect );
 404                                 }
 405                         }
 406                 }
 407         }
 408
 409         function getCategoryTop() {
 410                 $r = $this->getCategoryBottom();
 411                 return $r === ''
 412                         ? $r
 413                         : "<br style=\"clear:both;\"/>\n" . $r;
 414         }
 415
 416         function getSubcategorySection() {
 417                 # Don't show subcategories section if there are none.
 418                 $r = '';
 419                 $rescnt = count( $this->children );
 420                 $dbcnt = $this->cat->getSubcatCount();
 421                 $countmsg = $this->getCountMessage( $rescnt, $dbcnt, 'subcat' );
 422
 423                 if ( $rescnt > 0 ) {
 424                         # Showing subcategories
 425                         $r .= "<div id=\"mw-subcategories\">\n";
 426                         $r .= '<h2>' . wfMsg( 'subcategories' ) . "</h2>\n";
 427                         $r .= $countmsg;
 428                         $r .= $this->getSectionPagingLinks( 'subcat' );
 429                         $r .= $this->formatList( $this->children, $this->children_start_char );
 430                         $r .= $this->getSectionPagingLinks( 'subcat' );
 431                         $r .= "\n</div>";
 432                 }
 433                 return $r;
 434         }
 435
 436         function getPagesSection() {
 437                 $ti = htmlspecialchars( $this->title->getText() );
 438                 # Don't show articles section if there are none.
 439                 $r = '';
 440
 441                 # @todo FIXME: Here and in the other two sections: we don't need to bother
 442                 # with this rigamarole if the entire category contents fit on one page
 443                 # and have already been retrieved.  We can just use $rescnt in that
 444                 # case and save a query and some logic.
 445                 $dbcnt = $this->cat->getPageCount() - $this->cat->getSubcatCount()
 446                         - $this->cat->getFileCount();
 447                 $rescnt = count( $this->articles );
 448                 $countmsg = $this->getCountMessage( $rescnt, $dbcnt, 'article' );
 449
 450                 if ( $rescnt > 0 ) {
 451                         $r = "<div id=\"mw-pages\">\n";
 452                         $r .= '<h2>' . wfMsg( 'category_header', $ti ) . "</h2>\n";
 453                         $r .= $countmsg;
 454                         $r .= $this->getSectionPagingLinks( 'page' );
 455                         $r .= $this->formatList( $this->articles, $this->articles_start_char );
 456                         $r .= $this->getSectionPagingLinks( 'page' );
 457                         $r .= "\n</div>";
 458                 }
 459                 return $r;
 460         }
 461
 462         function getImageSection() {
 463                 $r = '';
 464                 $rescnt = $this->showGallery ? $this->gallery->count() : count( $this->imgsNoGallery );
 465                 if ( $rescnt > 0 ) {
 466                         $dbcnt = $this->cat->getFileCount();
 467                         $countmsg = $this->getCountMessage( $rescnt, $dbcnt, 'file' );
 468
 469                         $r .= "<div id=\"mw-category-media\">\n";
 470                         $r .= '<h2>' . wfMsg( 'category-media-header', htmlspecialchars( $this->title->getText() ) ) . "</h2>\n";
 471                         $r .= $countmsg;
 472                         $r .= $this->getSectionPagingLinks( 'file' );
 473                         if ( $this->showGallery ) {
 474                                 $r .= $this->gallery->toHTML();
 475                         } else {
 476                                 $r .= $this->formatList( $this->imgsNoGallery, $this->imgsNoGallery_start_char );
 477                         }
 478                         $r .= $this->getSectionPagingLinks( 'file' );
 479                         $r .= "\n</div>";
 480                 }
 481                 return $r;
 482         }
 483
 484         /**
 485          * Get the paging links for a section (subcats/pages/files), to go at the top and bottom
 486          * of the output.
 487          *
 488          * @param $type String: 'page', 'subcat', or 'file'
 489          * @return String: HTML output, possibly empty if there are no other pages
 490          */
 491         private function getSectionPagingLinks( $type ) {
 492                 if ( $this->until[$type] !== null ) {
 493                         return $this->pagingLinks( $this->nextPage[$type], $this->until[$type], $type );
 494                 } elseif ( $this->nextPage[$type] !== null || $this->from[$type] !== null ) {
 495                         return $this->pagingLinks( $this->from[$type], $this->nextPage[$type], $type );
 496                 } else {
 497                         return '';
 498                 }
 499         }
 500
 501         function getCategoryBottom() {
 502                 return '';
 503         }
 504
 505         /**
 506          * Format a list of articles chunked by letter, either as a
 507          * bullet list or a columnar format, depending on the length.
 508          *
 509          * @param $articles Array
 510          * @param $articles_start_char Array
 511          * @param $cutoff Int
 512          * @return String
 513          * @private
 514          */
 515         function formatList( $articles, $articles_start_char, $cutoff = 6 ) {
 516                 $list = '';
 517                 if ( count ( $articles ) > $cutoff ) {
 518                         $list = self::columnList( $articles, $articles_start_char );
 519                 } elseif ( count( $articles ) > 0 ) {
 520                         // for short lists of articles in categories.
 521                         $list = self::shortList( $articles, $articles_start_char );
 522                 }
 523
 524                 $pageLang = $this->title->getPageLanguage();
 525                 $attribs = array( 'lang' => $pageLang->getCode(), 'dir' => $pageLang->getDir(),
 526                         'class' => 'mw-content-'.$pageLang->getDir() );
 527                 $list = Html::rawElement( 'div', $attribs, $list );
 528
 529                 return $list;
 530         }
 531
 532         /**
 533          * Format a list of articles chunked by letter in a three-column
 534          * list, ordered vertically.
 535          *
 536          * TODO: Take the headers into account when creating columns, so they're
 537          * more visually equal.
 538          *
 539          * More distant TODO: Scrap this and use CSS columns, whenever IE finally
 540          * supports those.
 541          *
 542          * @param $articles Array
 543          * @param $articles_start_char Array
 544          * @return String
 545          * @private
 546          */
 547         static function columnList( $articles, $articles_start_char ) {
 548                 $columns = array_combine( $articles, $articles_start_char );
 549                 # Split into three columns
 550                 $columns = array_chunk( $columns, ceil( count( $columns ) / 3 ), true /* preserve keys */ );
 551
 552                 $ret = '<table width="100%"><tr valign="top"><td>';
 553                 $prevchar = null;
 554
 555                 foreach ( $columns as $column ) {
 556                         $colContents = array();
 557
 558                         # Kind of like array_flip() here, but we keep duplicates in an
 559                         # array instead of dropping them.
 560                         foreach ( $column as $article => $char ) {
 561                                 if ( !isset( $colContents[$char] ) ) {
 562                                         $colContents[$char] = array();
 563                                 }
 564                                 $colContents[$char][] = $article;
 565                         }
 566
 567                         $first = true;
 568                         foreach ( $colContents as $char => $articles ) {
 569                                 $ret .= '<h3>' . htmlspecialchars( $char );
 570                                 if ( $first && $char === $prevchar ) {
 571                                         # We're continuing a previous chunk at the top of a new
 572                                         # column, so add " cont." after the letter.
 573                                         $ret .= ' ' . wfMsgHtml( 'listingcontinuesabbrev' );
 574                                 }
 575                                 $ret .= "</h3>\n";
 576
 577                                 $ret .= '<ul><li>';
 578                                 $ret .= implode( "</li>\n<li>", $articles );
 579                                 $ret .= '</li></ul>';
 580
 581                                 $first = false;
 582                                 $prevchar = $char;
 583                         }
 584
 585                         $ret .= "</td>\n<td>";
 586                 }
 587
 588                 $ret .= '</td></tr></table>';
 589                 return $ret;
 590         }
 591
 592         /**
 593          * Format a list of articles chunked by letter in a bullet list.
 594          * @param $articles Array
 595          * @param $articles_start_char Array
 596          * @return String
 597          * @private
 598          */
 599         static function shortList( $articles, $articles_start_char ) {
 600                 $r = '<h3>' . htmlspecialchars( $articles_start_char[0] ) . "</h3>\n";
 601                 $r .= '<ul><li>' . $articles[0] . '</li>';
 602                 for ( $index = 1; $index < count( $articles ); $index++ ) {
 603                         if ( $articles_start_char[$index] != $articles_start_char[$index - 1] ) {
 604                                 $r .= "</ul><h3>" . htmlspecialchars( $articles_start_char[$index] ) . "</h3>\n<ul>";
 605                         }
 606
 607                         $r .= "<li>{$articles[$index]}</li>";
 608                 }
 609                 $r .= '</ul>';
 610                 return $r;
 611         }
 612
 613         /**
 614          * Create paging links, as a helper method to getSectionPagingLinks().
 615          *
 616          * @param $first String The 'until' parameter for the generated URL
 617          * @param $last String The 'from' parameter for the genererated URL
 618          * @param $type String A prefix for parameters, 'page' or 'subcat' or
 619          *     'file'
 620          * @return String HTML
 621          */
 622         private function pagingLinks( $first, $last, $type = '' ) {
 623                 global $wgLang;
 624
 625                 $limitText = $this->getLang()->formatNum( $this->limit );
 626
 627                 $prevLink = wfMsgExt( 'prevn', array( 'escape', 'parsemag' ), $limitText );
 628
 629                 if ( $first != '' ) {
 630                         $prevQuery = $this->query;
 631                         $prevQuery["{$type}until"] = $first;
 632                         unset( $prevQuery["{$type}from"] );
 633                         $prevLink = Linker::linkKnown(
 634                                 $this->addFragmentToTitle( $this->title, $type ),
 635                                 $prevLink,
 636                                 array(),
 637                                 $prevQuery
 638                         );
 639                 }
 640
 641                 $nextLink = wfMsgExt( 'nextn', array( 'escape', 'parsemag' ), $limitText );
 642
 643                 if ( $last != '' ) {
 644                         $lastQuery = $this->query;
 645                         $lastQuery["{$type}from"] = $last;
 646                         unset( $lastQuery["{$type}until"] );
 647                         $nextLink = Linker::linkKnown(
 648                                 $this->addFragmentToTitle( $this->title, $type ),
 649                                 $nextLink,
 650                                 array(),
 651                                 $lastQuery
 652                         );
 653                 }
 654
 655                 return "($prevLink) ($nextLink)";
 656         }
 657
 658         /**
 659          * Takes a title, and adds the fragment identifier that
 660          * corresponds to the correct segment of the category.
 661          *
 662          * @param Title $title: The title (usually $this->title)
 663          * @param String $section: Which section
 664          */
 665         private function addFragmentToTitle( $title, $section ) {
 666                 switch ( $section ) {
 667                         case 'page':
 668                                 $fragment = 'mw-pages';
 669                                 break;
 670                         case 'subcat':
 671                                 $fragment = 'mw-subcategories';
 672                                 break;
 673                         case 'file':
 674                                 $fragment = 'mw-category-media';
 675                                 break;
 676                         default:
 677                                 throw new MWException( __METHOD__ .
 678                                         " Invalid section $section." );
 679                 }
 680
 681                 return Title::makeTitle( $title->getNamespace(),
 682                         $title->getDBkey(), $fragment );
 683         }
 684         /**
 685          * What to do if the category table conflicts with the number of results
 686          * returned?  This function says what. Each type is considered independently
 687          * of the other types.
 688          *
 689          * Note for grepping: uses the messages category-article-count,
 690          * category-article-count-limited, category-subcat-count,
 691          * category-subcat-count-limited, category-file-count,
 692          * category-file-count-limited.
 693          *
 694          * @param $rescnt Int: The number of items returned by our database query.
 695          * @param $dbcnt Int: The number of items according to the category table.
 696          * @param $type String: 'subcat', 'article', or 'file'
 697          * @return String: A message giving the number of items, to output to HTML.
 698          */
 699         private function getCountMessage( $rescnt, $dbcnt, $type ) {
 700                 # There are three cases:
 701                 #   1) The category table figure seems sane.  It might be wrong, but
 702                 #      we can't do anything about it if we don't recalculate it on ev-
 703                 #      ery category view.
 704                 #   2) The category table figure isn't sane, like it's smaller than the
 705                 #      number of actual results, *but* the number of results is less
 706                 #      than $this->limit and there's no offset.  In this case we still
 707                 #      know the right figure.
 708                 #   3) We have no idea.
 709
 710                 # Check if there's a "from" or "until" for anything
 711
 712                 // This is a little ugly, but we seem to use different names
 713                 // for the paging types then for the messages.
 714                 if ( $type === 'article' ) {
 715                         $pagingType = 'page';
 716                 } else {
 717                         $pagingType = $type;
 718                 }
 719
 720                 $fromOrUntil = false;
 721                 if ( $this->from[$pagingType] !== null || $this->until[$pagingType] !== null ) {
 722                         $fromOrUntil = true;
 723                 }
 724
 725                 if ( $dbcnt == $rescnt || ( ( $rescnt == $this->limit || $fromOrUntil )
 726                         && $dbcnt > $rescnt ) ) {
 727                         # Case 1: seems sane.
 728                         $totalcnt = $dbcnt;
 729                 } elseif ( $rescnt < $this->limit && !$fromOrUntil ) {
 730                         # Case 2: not sane, but salvageable.  Use the number of results.
 731                         # Since there are fewer than 200, we can also take this opportunity
 732                         # to refresh the incorrect category table entry -- which should be
 733                         # quick due to the small number of entries.
 734                         $totalcnt = $rescnt;
 735                         $this->cat->refreshCounts();
 736                 } else {
 737                         # Case 3: hopeless.  Don't give a total count at all.
 738                         return wfMsgExt( "category-$type-count-limited", 'parse',
 739                                 $this->getLang()->formatNum( $rescnt ) );
 740                 }
 741                 return wfMsgExt(
 742                         "category-$type-count",
 743                         'parse',
 744                         $this->getLang()->formatNum( $rescnt ),
 745                         $this->getLang()->formatNum( $totalcnt )
 746                 );
 747         }
 748
 749         /**
 750          * Returns a language object from the context
 751          *
 752          * @return Language
 753          */
 754         protected function getLang() {
 755                 return $this->context->getLang();
 756         }
 757 }