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