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