includes/CategoryPage.php

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