includes/CategoryViewer.php

   1 <?php
   2 /**
   3  * List and paging of category members.
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation; either version 2 of the License, or
   8  * (at your option) any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License along
  16  * with this program; if not, write to the Free Software Foundation, Inc.,
  17  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  18  * http://www.gnu.org/copyleft/gpl.html
  19  *
  20  * @file
  21  */
  22
  23 class CategoryViewer extends ContextSource {
  24         /** @var int */
  25         public $limit;
  26
  27         /** @var array */
  28         protected $from;
  29
  30         /** @var array */
  31         protected $until;
  32
  33         /** @var string[] */
  34         public $articles;
  35
  36         /** @var array */
  37         public $articles_start_char;
  38
  39         /** @var array */
  40         protected $children;
  41
  42         /** @var array */
  43         protected $children_start_char;
  44
  45         /** @var bool */
  46         protected $showGallery;
  47
  48         /** @var array */
  49         protected $imgsNoGallery_start_char;
  50
  51         /** @var array */
  52         protected $imgsNoGallery;
  53
  54         /** @var array */
  55         protected $nextPage;
  56
  57         /** @var array */
  58         protected $flip;
  59
  60         /** @var Title */
  61         protected $title;
  62
  63         /** @var Collation */
  64         protected $collation;
  65
  66         /** @var ImageGallery */
  67         protected $gallery;
  68
  69         /** @var Category Category object for this page. */
  70         private $cat;
  71
  72         /** @var array The original query array, to be used in generating paging links. */
  73         private $query;
  74
  75         /**
  76          * @since 1.19 $context is a second, required parameter
  77          * @param Title $title
  78          * @param IContextSource $context
  79          * @param array $from An array with keys page, subcat,
  80          *        and file for offset of results of each section (since 1.17)
  81          * @param array $until An array with 3 keys for until of each section (since 1.17)
  82          * @param array $query
  83          */
  84         function __construct( $title, IContextSource $context, $from = array(),
  85                 $until = array(), $query = array()
  86         ) {
  87                 global $wgCategoryPagingLimit;
  88                 $this->title = $title;
  89                 $this->setContext( $context );
  90                 $this->from = $from;
  91                 $this->until = $until;
  92                 $this->limit = $wgCategoryPagingLimit;
  93                 $this->cat = Category::newFromTitle( $title );
  94                 $this->query = $query;
  95                 $this->collation = Collation::singleton();
  96                 unset( $this->query['title'] );
  97         }
  98
  99         /**
 100          * Format the category data list.
 101          *
 102          * @return string HTML output
 103          */
 104         public function getHTML() {
 105                 global $wgCategoryMagicGallery;
 106                 wfProfileIn( __METHOD__ );
 107
 108                 $this->showGallery = $wgCategoryMagicGallery && !$this->getOutput()->mNoGallery;
 109
 110                 $this->clearCategoryState();
 111                 $this->doCategoryQuery();
 112                 $this->finaliseCategoryState();
 113
 114                 $r = $this->getSubcategorySection() .
 115                         $this->getPagesSection() .
 116                         $this->getImageSection();
 117
 118                 if ( $r == '' ) {
 119                         // If there is no category content to display, only
 120                         // show the top part of the navigation links.
 121                         // @todo FIXME: Cannot be completely suppressed because it
 122                         //        is unknown if 'until' or 'from' makes this
 123                         //        give 0 results.
 124                         $r = $r . $this->getCategoryTop();
 125                 } else {
 126                         $r = $this->getCategoryTop() .
 127                                 $r .
 128                                 $this->getCategoryBottom();
 129                 }
 130
 131                 // Give a proper message if category is empty
 132                 if ( $r == '' ) {
 133                         $r = $this->msg( 'category-empty' )->parseAsBlock();
 134                 }
 135
 136                 $lang = $this->getLanguage();
 137                 $langAttribs = array( 'lang' => $lang->getCode(), 'dir' => $lang->getDir() );
 138                 # put a div around the headings which are in the user language
 139                 $r = Html::openElement( 'div', $langAttribs ) . $r . '</div>';
 140
 141                 wfProfileOut( __METHOD__ );
 142                 return $r;
 143         }
 144
 145         function clearCategoryState() {
 146                 $this->articles = array();
 147                 $this->articles_start_char = array();
 148                 $this->children = array();
 149                 $this->children_start_char = array();
 150                 if ( $this->showGallery ) {
 151                         // Note that null for mode is taken to mean use default.
 152                         $mode = $this->getRequest()->getVal( 'gallerymode', null );
 153                         try {
 154                                 $this->gallery = ImageGalleryBase::factory( $mode );
 155                         } catch ( MWException $e ) {
 156                                 // User specified something invalid, fallback to default.
 157                                 $this->gallery = ImageGalleryBase::factory();
 158                         }
 159
 160                         $this->gallery->setHideBadImages();
 161                         $this->gallery->setContext( $this->getContext() );
 162                 } else {
 163                         $this->imgsNoGallery = array();
 164                         $this->imgsNoGallery_start_char = array();
 165                 }
 166         }
 167
 168         /**
 169          * Add a subcategory to the internal lists, using a Category object
 170          * @param Category $cat
 171          * @param string $sortkey
 172          * @param int $pageLength
 173          */
 174         function addSubcategoryObject( Category $cat, $sortkey, $pageLength ) {
 175                 // Subcategory; strip the 'Category' namespace from the link text.
 176                 $title = $cat->getTitle();
 177
 178                 $link = Linker::link( $title, htmlspecialchars( $title->getText() ) );
 179                 if ( $title->isRedirect() ) {
 180                         // This didn't used to add redirect-in-category, but might
 181                         // as well be consistent with the rest of the sections
 182                         // on a category page.
 183                         $link = '<span class="redirect-in-category">' . $link . '</span>';
 184                 }
 185                 $this->children[] = $link;
 186
 187                 $this->children_start_char[] =
 188                         $this->getSubcategorySortChar( $cat->getTitle(), $sortkey );
 189         }
 190
 191         /**
 192          * Get the character to be used for sorting subcategories.
 193          * If there's a link from Category:A to Category:B, the sortkey of the resulting
 194          * entry in the categorylinks table is Category:A, not A, which it SHOULD be.
 195          * Workaround: If sortkey == "Category:".$title, than use $title for sorting,
 196          * else use sortkey...
 197          *
 198          * @param Title $title
 199          * @param string $sortkey The human-readable sortkey (before transforming to icu or whatever).
 200          * @return string
 201          */
 202         function getSubcategorySortChar( $title, $sortkey ) {
 203                 global $wgContLang;
 204
 205                 if ( $title->getPrefixedText() == $sortkey ) {
 206                         $word = $title->getDBkey();
 207                 } else {
 208                         $word = $sortkey;
 209                 }
 210
 211                 $firstChar = $this->collation->getFirstLetter( $word );
 212
 213                 return $wgContLang->convert( $firstChar );
 214         }
 215
 216         /**
 217          * Add a page in the image namespace
 218          * @param Title $title
 219          * @param string $sortkey
 220          * @param int $pageLength
 221          * @param bool $isRedirect
 222          */
 223         function addImage( Title $title, $sortkey, $pageLength, $isRedirect = false ) {
 224                 global $wgContLang;
 225                 if ( $this->showGallery ) {
 226                         $flip = $this->flip['file'];
 227                         if ( $flip ) {
 228                                 $this->gallery->insert( $title );
 229                         } else {
 230                                 $this->gallery->add( $title );
 231                         }
 232                 } else {
 233                         $link = Linker::link( $title );
 234                         if ( $isRedirect ) {
 235                                 // This seems kind of pointless given 'mw-redirect' class,
 236                                 // but keeping for back-compatibility with user css.
 237                                 $link = '<span class="redirect-in-category">' . $link . '</span>';
 238                         }
 239                         $this->imgsNoGallery[] = $link;
 240
 241                         $this->imgsNoGallery_start_char[] = $wgContLang->convert(
 242                                 $this->collation->getFirstLetter( $sortkey ) );
 243                 }
 244         }
 245
 246         /**
 247          * Add a miscellaneous page
 248          * @param Title $title
 249          * @param string $sortkey
 250          * @param int $pageLength
 251          * @param bool $isRedirect
 252          */
 253         function addPage( $title, $sortkey, $pageLength, $isRedirect = false ) {
 254                 global $wgContLang;
 255
 256                 $link = Linker::link( $title );
 257                 if ( $isRedirect ) {
 258                         // This seems kind of pointless given 'mw-redirect' class,
 259                         // but keeping for back-compatibility with user css.
 260                         $link = '<span class="redirect-in-category">' . $link . '</span>';
 261                 }
 262                 $this->articles[] = $link;
 263
 264                 $this->articles_start_char[] = $wgContLang->convert(
 265                         $this->collation->getFirstLetter( $sortkey ) );
 266         }
 267
 268         function finaliseCategoryState() {
 269                 if ( $this->flip['subcat'] ) {
 270                         $this->children = array_reverse( $this->children );
 271                         $this->children_start_char = array_reverse( $this->children_start_char );
 272                 }
 273                 if ( $this->flip['page'] ) {
 274                         $this->articles = array_reverse( $this->articles );
 275                         $this->articles_start_char = array_reverse( $this->articles_start_char );
 276                 }
 277                 if ( !$this->showGallery && $this->flip['file'] ) {
 278                         $this->imgsNoGallery = array_reverse( $this->imgsNoGallery );
 279                         $this->imgsNoGallery_start_char = array_reverse( $this->imgsNoGallery_start_char );
 280                 }
 281         }
 282
 283         function doCategoryQuery() {
 284                 $dbr = wfGetDB( DB_SLAVE, 'category' );
 285
 286                 $this->nextPage = array(
 287                         'page' => null,
 288                         'subcat' => null,
 289                         'file' => null,
 290                 );
 291                 $this->flip = array( 'page' => false, 'subcat' => false, 'file' => false );
 292
 293                 foreach ( array( 'page', 'subcat', 'file' ) as $type ) {
 294                         # Get the sortkeys for start/end, if applicable.  Note that if
 295                         # the collation in the database differs from the one
 296                         # set in $wgCategoryCollation, pagination might go totally haywire.
 297                         $extraConds = array( 'cl_type' => $type );
 298                         if ( isset( $this->from[$type] ) && $this->from[$type] !== null ) {
 299                                 $extraConds[] = 'cl_sortkey >= '
 300                                         . $dbr->addQuotes( $this->collation->getSortKey( $this->from[$type] ) );
 301                         } elseif ( isset( $this->until[$type] ) && $this->until[$type] !== null ) {
 302                                 $extraConds[] = 'cl_sortkey < '
 303                                         . $dbr->addQuotes( $this->collation->getSortKey( $this->until[$type] ) );
 304                                 $this->flip[$type] = true;
 305                         }
 306
 307                         $res = $dbr->select(
 308                                 array( 'page', 'categorylinks', 'category' ),
 309                                 array( 'page_id', 'page_title', 'page_namespace', 'page_len',
 310                                         'page_is_redirect', 'cl_sortkey', 'cat_id', 'cat_title',
 311                                         'cat_subcats', 'cat_pages', 'cat_files',
 312                                         'cl_sortkey_prefix', 'cl_collation' ),
 313                                 array_merge( array( 'cl_to' => $this->title->getDBkey() ), $extraConds ),
 314                                 __METHOD__,
 315                                 array(
 316                                         'USE INDEX' => array( 'categorylinks' => 'cl_sortkey' ),
 317                                         'LIMIT' => $this->limit + 1,
 318                                         'ORDER BY' => $this->flip[$type] ? 'cl_sortkey DESC' : 'cl_sortkey',
 319                                 ),
 320                                 array(
 321                                         'categorylinks' => array( 'INNER JOIN', 'cl_from = page_id' ),
 322                                         'category' => array( 'LEFT JOIN', array(
 323                                                 'cat_title = page_title',
 324                                                 'page_namespace' => NS_CATEGORY
 325                                         ))
 326                                 )
 327                         );
 328
 329                         $count = 0;
 330                         foreach ( $res as $row ) {
 331                                 $title = Title::newFromRow( $row );
 332                                 if ( $row->cl_collation === '' ) {
 333                                         // Hack to make sure that while updating from 1.16 schema
 334                                         // and db is inconsistent, that the sky doesn't fall.
 335                                         // See r83544. Could perhaps be removed in a couple decades...
 336                                         $humanSortkey = $row->cl_sortkey;
 337                                 } else {
 338                                         $humanSortkey = $title->getCategorySortkey( $row->cl_sortkey_prefix );
 339                                 }
 340
 341                                 if ( ++$count > $this->limit ) {
 342                                         # We've reached the one extra which shows that there
 343                                         # are additional pages to be had. Stop here...
 344                                         $this->nextPage[$type] = $humanSortkey;
 345                                         break;
 346                                 }
 347
 348                                 if ( $title->getNamespace() == NS_CATEGORY ) {
 349                                         $cat = Category::newFromRow( $row, $title );
 350                                         $this->addSubcategoryObject( $cat, $humanSortkey, $row->page_len );
 351                                 } elseif ( $title->getNamespace() == NS_FILE ) {
 352                                         $this->addImage( $title, $humanSortkey, $row->page_len, $row->page_is_redirect );
 353                                 } else {
 354                                         $this->addPage( $title, $humanSortkey, $row->page_len, $row->page_is_redirect );
 355                                 }
 356                         }
 357                 }
 358         }
 359
 360         /**
 361          * @return string
 362          */
 363         function getCategoryTop() {
 364                 $r = $this->getCategoryBottom();
 365                 return $r === ''
 366                         ? $r
 367                         : "<br style=\"clear:both;\"/>\n" . $r;
 368         }
 369
 370         /**
 371          * @return string
 372          */
 373         function getSubcategorySection() {
 374                 # Don't show subcategories section if there are none.
 375                 $r = '';
 376                 $rescnt = count( $this->children );
 377                 $dbcnt = $this->cat->getSubcatCount();
 378                 $countmsg = $this->getCountMessage( $rescnt, $dbcnt, 'subcat' );
 379
 380                 if ( $rescnt > 0 ) {
 381                         # Showing subcategories
 382                         $r .= "<div id=\"mw-subcategories\">\n";
 383                         $r .= '<h2>' . $this->msg( 'subcategories' )->text() . "</h2>\n";
 384                         $r .= $countmsg;
 385                         $r .= $this->getSectionPagingLinks( 'subcat' );
 386                         $r .= $this->formatList( $this->children, $this->children_start_char );
 387                         $r .= $this->getSectionPagingLinks( 'subcat' );
 388                         $r .= "\n</div>";
 389                 }
 390                 return $r;
 391         }
 392
 393         /**
 394          * @return string
 395          */
 396         function getPagesSection() {
 397                 $ti = wfEscapeWikiText( $this->title->getText() );
 398                 # Don't show articles section if there are none.
 399                 $r = '';
 400
 401                 # @todo FIXME: Here and in the other two sections: we don't need to bother
 402                 # with this rigmarole if the entire category contents fit on one page
 403                 # and have already been retrieved.  We can just use $rescnt in that
 404                 # case and save a query and some logic.
 405                 $dbcnt = $this->cat->getPageCount() - $this->cat->getSubcatCount()
 406                         - $this->cat->getFileCount();
 407                 $rescnt = count( $this->articles );
 408                 $countmsg = $this->getCountMessage( $rescnt, $dbcnt, 'article' );
 409
 410                 if ( $rescnt > 0 ) {
 411                         $r = "<div id=\"mw-pages\">\n";
 412                         $r .= '<h2>' . $this->msg( 'category_header', $ti )->text() . "</h2>\n";
 413                         $r .= $countmsg;
 414                         $r .= $this->getSectionPagingLinks( 'page' );
 415                         $r .= $this->formatList( $this->articles, $this->articles_start_char );
 416                         $r .= $this->getSectionPagingLinks( 'page' );
 417                         $r .= "\n</div>";
 418                 }
 419                 return $r;
 420         }
 421
 422         /**
 423          * @return string
 424          */
 425         function getImageSection() {
 426                 $r = '';
 427                 $rescnt = $this->showGallery ? $this->gallery->count() : count( $this->imgsNoGallery );
 428                 if ( $rescnt > 0 ) {
 429                         $dbcnt = $this->cat->getFileCount();
 430                         $countmsg = $this->getCountMessage( $rescnt, $dbcnt, 'file' );
 431
 432                         $r .= "<div id=\"mw-category-media\">\n";
 433                         $r .= '<h2>' .
 434                                 $this->msg(
 435                                         'category-media-header',
 436                                         wfEscapeWikiText( $this->title->getText() )
 437                                 )->text() .
 438                                 "</h2>\n";
 439                         $r .= $countmsg;
 440                         $r .= $this->getSectionPagingLinks( 'file' );
 441                         if ( $this->showGallery ) {
 442                                 $r .= $this->gallery->toHTML();
 443                         } else {
 444                                 $r .= $this->formatList( $this->imgsNoGallery, $this->imgsNoGallery_start_char );
 445                         }
 446                         $r .= $this->getSectionPagingLinks( 'file' );
 447                         $r .= "\n</div>";
 448                 }
 449                 return $r;
 450         }
 451
 452         /**
 453          * Get the paging links for a section (subcats/pages/files), to go at the top and bottom
 454          * of the output.
 455          *
 456          * @param string $type 'page', 'subcat', or 'file'
 457          * @return string HTML output, possibly empty if there are no other pages
 458          */
 459         private function getSectionPagingLinks( $type ) {
 460                 if ( isset( $this->until[$type] ) && $this->until[$type] !== null ) {
 461                         return $this->pagingLinks( $this->nextPage[$type], $this->until[$type], $type );
 462                 } elseif ( $this->nextPage[$type] !== null
 463                         || ( isset( $this->from[$type] ) && $this->from[$type] !== null )
 464                 ) {
 465                         return $this->pagingLinks( $this->from[$type], $this->nextPage[$type], $type );
 466                 } else {
 467                         return '';
 468                 }
 469         }
 470
 471         /**
 472          * @return string
 473          */
 474         function getCategoryBottom() {
 475                 return '';
 476         }
 477
 478         /**
 479          * Format a list of articles chunked by letter, either as a
 480          * bullet list or a columnar format, depending on the length.
 481          *
 482          * @param array $articles
 483          * @param array $articles_start_char
 484          * @param int $cutoff
 485          * @return string
 486          * @private
 487          */
 488         function formatList( $articles, $articles_start_char, $cutoff = 6 ) {
 489                 $list = '';
 490                 if ( count( $articles ) > $cutoff ) {
 491                         $list = self::columnList( $articles, $articles_start_char );
 492                 } elseif ( count( $articles ) > 0 ) {
 493                         // for short lists of articles in categories.
 494                         $list = self::shortList( $articles, $articles_start_char );
 495                 }
 496
 497                 $pageLang = $this->title->getPageLanguage();
 498                 $attribs = array( 'lang' => $pageLang->getCode(), 'dir' => $pageLang->getDir(),
 499                         'class' => 'mw-content-' . $pageLang->getDir() );
 500                 $list = Html::rawElement( 'div', $attribs, $list );
 501
 502                 return $list;
 503         }
 504
 505         /**
 506          * Format a list of articles chunked by letter in a three-column
 507          * list, ordered vertically.
 508          *
 509          * TODO: Take the headers into account when creating columns, so they're
 510          * more visually equal.
 511          *
 512          * More distant TODO: Scrap this and use CSS columns, whenever IE finally
 513          * supports those.
 514          *
 515          * @param array $articles
 516          * @param string[] $articles_start_char
 517          * @return string
 518          * @private
 519          */
 520         static function columnList( $articles, $articles_start_char ) {
 521                 $columns = array_combine( $articles, $articles_start_char );
 522                 # Split into three columns
 523                 $columns = array_chunk( $columns, ceil( count( $columns ) / 3 ), true /* preserve keys */ );
 524
 525                 $ret = '<table style="width: 100%;"><tr style="vertical-align: top;">';
 526                 $prevchar = null;
 527
 528                 foreach ( $columns as $column ) {
 529                         $ret .= '<td style="width: 33.3%;">';
 530                         $colContents = array();
 531
 532                         # Kind of like array_flip() here, but we keep duplicates in an
 533                         # array instead of dropping them.
 534                         foreach ( $column as $article => $char ) {
 535                                 if ( !isset( $colContents[$char] ) ) {
 536                                         $colContents[$char] = array();
 537                                 }
 538                                 $colContents[$char][] = $article;
 539                         }
 540
 541                         $first = true;
 542                         foreach ( $colContents as $char => $articles ) {
 543                                 # Change space to non-breaking space to keep headers aligned
 544                                 $h3char = $char === ' ' ? '&#160;' : htmlspecialchars( $char );
 545
 546                                 $ret .= '<h3>' . $h3char;
 547                                 if ( $first && $char === $prevchar ) {
 548                                         # We're continuing a previous chunk at the top of a new
 549                                         # column, so add " cont." after the letter.
 550                                         $ret .= ' ' . wfMessage( 'listingcontinuesabbrev' )->escaped();
 551                                 }
 552                                 $ret .= "</h3>\n";
 553
 554                                 $ret .= '<ul><li>';
 555                                 $ret .= implode( "</li>\n<li>", $articles );
 556                                 $ret .= '</li></ul>';
 557
 558                                 $first = false;
 559                                 $prevchar = $char;
 560                         }
 561
 562                         $ret .= "</td>\n";
 563                 }
 564
 565                 $ret .= '</tr></table>';
 566                 return $ret;
 567         }
 568
 569         /**
 570          * Format a list of articles chunked by letter in a bullet list.
 571          * @param array $articles
 572          * @param string[] $articles_start_char
 573          * @return string
 574          * @private
 575          */
 576         static function shortList( $articles, $articles_start_char ) {
 577                 $r = '<h3>' . htmlspecialchars( $articles_start_char[0] ) . "</h3>\n";
 578                 $r .= '<ul><li>' . $articles[0] . '</li>';
 579                 $articleCount = count( $articles );
 580                 for ( $index = 1; $index < $articleCount; $index++ ) {
 581                         if ( $articles_start_char[$index] != $articles_start_char[$index - 1] ) {
 582                                 $r .= "</ul><h3>" . htmlspecialchars( $articles_start_char[$index] ) . "</h3>\n<ul>";
 583                         }
 584
 585                         $r .= "<li>{$articles[$index]}</li>";
 586                 }
 587                 $r .= '</ul>';
 588                 return $r;
 589         }
 590
 591         /**
 592          * Create paging links, as a helper method to getSectionPagingLinks().
 593          *
 594          * @param string $first The 'until' parameter for the generated URL
 595          * @param string $last The 'from' parameter for the generated URL
 596          * @param string $type A prefix for parameters, 'page' or 'subcat' or
 597          *     'file'
 598          * @return string HTML
 599          */
 600         private function pagingLinks( $first, $last, $type = '' ) {
 601                 $prevLink = $this->msg( 'prevn' )->numParams( $this->limit )->escaped();
 602
 603                 if ( $first != '' ) {
 604                         $prevQuery = $this->query;
 605                         $prevQuery["{$type}until"] = $first;
 606                         unset( $prevQuery["{$type}from"] );
 607                         $prevLink = Linker::linkKnown(
 608                                 $this->addFragmentToTitle( $this->title, $type ),
 609                                 $prevLink,
 610                                 array(),
 611                                 $prevQuery
 612                         );
 613                 }
 614
 615                 $nextLink = $this->msg( 'nextn' )->numParams( $this->limit )->escaped();
 616
 617                 if ( $last != '' ) {
 618                         $lastQuery = $this->query;
 619                         $lastQuery["{$type}from"] = $last;
 620                         unset( $lastQuery["{$type}until"] );
 621                         $nextLink = Linker::linkKnown(
 622                                 $this->addFragmentToTitle( $this->title, $type ),
 623                                 $nextLink,
 624                                 array(),
 625                                 $lastQuery
 626                         );
 627                 }
 628
 629                 return $this->msg( 'categoryviewer-pagedlinks' )->rawParams( $prevLink, $nextLink )->escaped();
 630         }
 631
 632         /**
 633          * Takes a title, and adds the fragment identifier that
 634          * corresponds to the correct segment of the category.
 635          *
 636          * @param Title $title The title (usually $this->title)
 637          * @param string $section Which section
 638          * @throws MWException
 639          * @return Title
 640          */
 641         private function addFragmentToTitle( $title, $section ) {
 642                 switch ( $section ) {
 643                         case 'page':
 644                                 $fragment = 'mw-pages';
 645                                 break;
 646                         case 'subcat':
 647                                 $fragment = 'mw-subcategories';
 648                                 break;
 649                         case 'file':
 650                                 $fragment = 'mw-category-media';
 651                                 break;
 652                         default:
 653                                 throw new MWException( __METHOD__ .
 654                                         " Invalid section $section." );
 655                 }
 656
 657                 return Title::makeTitle( $title->getNamespace(),
 658                         $title->getDBkey(), $fragment );
 659         }
 660
 661         /**
 662          * What to do if the category table conflicts with the number of results
 663          * returned?  This function says what. Each type is considered independently
 664          * of the other types.
 665          *
 666          * @param int $rescnt The number of items returned by our database query.
 667          * @param int $dbcnt The number of items according to the category table.
 668          * @param string $type 'subcat', 'article', or 'file'
 669          * @return string A message giving the number of items, to output to HTML.
 670          */
 671         private function getCountMessage( $rescnt, $dbcnt, $type ) {
 672                 // There are three cases:
 673                 //   1) The category table figure seems sane.  It might be wrong, but
 674                 //      we can't do anything about it if we don't recalculate it on ev-
 675                 //      ery category view.
 676                 //   2) The category table figure isn't sane, like it's smaller than the
 677                 //      number of actual results, *but* the number of results is less
 678                 //      than $this->limit and there's no offset.  In this case we still
 679                 //      know the right figure.
 680                 //   3) We have no idea.
 681
 682                 // Check if there's a "from" or "until" for anything
 683
 684                 // This is a little ugly, but we seem to use different names
 685                 // for the paging types then for the messages.
 686                 if ( $type === 'article' ) {
 687                         $pagingType = 'page';
 688                 } else {
 689                         $pagingType = $type;
 690                 }
 691
 692                 $fromOrUntil = false;
 693                 if ( ( isset( $this->from[$pagingType] ) && $this->from[$pagingType] !== null ) ||
 694                         ( isset( $this->until[$pagingType] ) && $this->until[$pagingType] !== null )
 695                 ) {
 696                         $fromOrUntil = true;
 697                 }
 698
 699                 if ( $dbcnt == $rescnt ||
 700                         ( ( $rescnt == $this->limit || $fromOrUntil ) && $dbcnt > $rescnt )
 701                 ) {
 702                         // Case 1: seems sane.
 703                         $totalcnt = $dbcnt;
 704                 } elseif ( $rescnt < $this->limit && !$fromOrUntil ) {
 705                         // Case 2: not sane, but salvageable.  Use the number of results.
 706                         // Since there are fewer than 200, we can also take this opportunity
 707                         // to refresh the incorrect category table entry -- which should be
 708                         // quick due to the small number of entries.
 709                         $totalcnt = $rescnt;
 710                         $category = $this->cat;
 711                         wfGetDB( DB_MASTER )->onTransactionIdle( function() use ( $category ) {
 712                                 $category->refreshCounts();
 713                         } );
 714                 } else {
 715                         // Case 3: hopeless.  Don't give a total count at all.
 716                         // Messages: category-subcat-count-limited, category-article-count-limited,
 717                         // category-file-count-limited
 718                         return $this->msg( "category-$type-count-limited" )->numParams( $rescnt )->parseAsBlock();
 719                 }
 720                 // Messages: category-subcat-count, category-article-count, category-file-count
 721                 return $this->msg( "category-$type-count" )->numParams( $rescnt, $totalcnt )->parseAsBlock();
 722         }
 723 }