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