includes/parser/LinkHolderArray.php

   1 <?php
   2 /**
   3  * Holder of replacement pairs for wiki links
   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  * @ingroup Parser
  22  */
  23
  24 /**
  25  * @ingroup Parser
  26  */
  27 class LinkHolderArray {
  28         var $internals = array(), $interwikis = array();
  29         var $size = 0;
  30         var $parent;
  31         protected $tempIdOffset;
  32
  33         function __construct( $parent ) {
  34                 $this->parent = $parent;
  35         }
  36
  37         /**
  38          * Reduce memory usage to reduce the impact of circular references
  39          */
  40         function __destruct() {
  41                 foreach ( $this as $name => $value ) {
  42                         unset( $this->$name );
  43                 }
  44         }
  45
  46         /**
  47          * Don't serialize the parent object, it is big, and not needed when it is
  48          * a parameter to mergeForeign(), which is the only application of
  49          * serializing at present.
  50          *
  51          * Compact the titles, only serialize the text form.
  52          * @return array
  53          */
  54         function __sleep() {
  55                 foreach ( $this->internals as &$nsLinks ) {
  56                         foreach ( $nsLinks as &$entry ) {
  57                                 unset( $entry['title'] );
  58                         }
  59                 }
  60                 unset( $nsLinks );
  61                 unset( $entry );
  62
  63                 foreach ( $this->interwikis as &$entry ) {
  64                         unset( $entry['title'] );
  65                 }
  66                 unset( $entry );
  67
  68                 return array( 'internals', 'interwikis', 'size' );
  69         }
  70
  71         /**
  72          * Recreate the Title objects
  73          */
  74         function __wakeup() {
  75                 foreach ( $this->internals as &$nsLinks ) {
  76                         foreach ( $nsLinks as &$entry ) {
  77                                 $entry['title'] = Title::newFromText( $entry['pdbk'] );
  78                         }
  79                 }
  80                 unset( $nsLinks );
  81                 unset( $entry );
  82
  83                 foreach ( $this->interwikis as &$entry ) {
  84                         $entry['title'] = Title::newFromText( $entry['pdbk'] );
  85                 }
  86                 unset( $entry );
  87         }
  88
  89         /**
  90          * Merge another LinkHolderArray into this one
  91          * @param LinkHolderArray $other
  92          */
  93         function merge( $other ) {
  94                 foreach ( $other->internals as $ns => $entries ) {
  95                         $this->size += count( $entries );
  96                         if ( !isset( $this->internals[$ns] ) ) {
  97                                 $this->internals[$ns] = $entries;
  98                         } else {
  99                                 $this->internals[$ns] += $entries;
 100                         }
 101                 }
 102                 $this->interwikis += $other->interwikis;
 103         }
 104
 105         /**
 106          * Merge a LinkHolderArray from another parser instance into this one. The
 107          * keys will not be preserved. Any text which went with the old
 108          * LinkHolderArray and needs to work with the new one should be passed in
 109          * the $texts array. The strings in this array will have their link holders
 110          * converted for use in the destination link holder. The resulting array of
 111          * strings will be returned.
 112          *
 113          * @param LinkHolderArray $other
 114          * @param array $texts Array of strings
 115          * @return array
 116          */
 117         function mergeForeign( $other, $texts ) {
 118                 $this->tempIdOffset = $idOffset = $this->parent->nextLinkID();
 119                 $maxId = 0;
 120
 121                 # Renumber internal links
 122                 foreach ( $other->internals as $ns => $nsLinks ) {
 123                         foreach ( $nsLinks as $key => $entry ) {
 124                                 $newKey = $idOffset + $key;
 125                                 $this->internals[$ns][$newKey] = $entry;
 126                                 $maxId = $newKey > $maxId ? $newKey : $maxId;
 127                         }
 128                 }
 129                 $texts = preg_replace_callback( '/(<!--LINK \d+:)(\d+)(-->)/',
 130                         array( $this, 'mergeForeignCallback' ), $texts );
 131
 132                 # Renumber interwiki links
 133                 foreach ( $other->interwikis as $key => $entry ) {
 134                         $newKey = $idOffset + $key;
 135                         $this->interwikis[$newKey] = $entry;
 136                         $maxId = $newKey > $maxId ? $newKey : $maxId;
 137                 }
 138                 $texts = preg_replace_callback( '/(<!--IWLINK )(\d+)(-->)/',
 139                         array( $this, 'mergeForeignCallback' ), $texts );
 140
 141                 # Set the parent link ID to be beyond the highest used ID
 142                 $this->parent->setLinkID( $maxId + 1 );
 143                 $this->tempIdOffset = null;
 144                 return $texts;
 145         }
 146
 147         protected function mergeForeignCallback( $m ) {
 148                 return $m[1] . ( $m[2] + $this->tempIdOffset ) . $m[3];
 149         }
 150
 151         /**
 152          * Get a subset of the current LinkHolderArray which is sufficient to
 153          * interpret the given text.
 154          * @param string $text
 155          * @return LinkHolderArray
 156          */
 157         function getSubArray( $text ) {
 158                 $sub = new LinkHolderArray( $this->parent );
 159
 160                 # Internal links
 161                 $pos = 0;
 162                 while ( $pos < strlen( $text ) ) {
 163                         if ( !preg_match( '/<!--LINK (\d+):(\d+)-->/',
 164                                 $text, $m, PREG_OFFSET_CAPTURE, $pos )
 165                         ) {
 166                                 break;
 167                         }
 168                         $ns = $m[1][0];
 169                         $key = $m[2][0];
 170                         $sub->internals[$ns][$key] = $this->internals[$ns][$key];
 171                         $pos = $m[0][1] + strlen( $m[0][0] );
 172                 }
 173
 174                 # Interwiki links
 175                 $pos = 0;
 176                 while ( $pos < strlen( $text ) ) {
 177                         if ( !preg_match( '/<!--IWLINK (\d+)-->/', $text, $m, PREG_OFFSET_CAPTURE, $pos ) ) {
 178                                 break;
 179                         }
 180                         $key = $m[1][0];
 181                         $sub->interwikis[$key] = $this->interwikis[$key];
 182                         $pos = $m[0][1] + strlen( $m[0][0] );
 183                 }
 184                 return $sub;
 185         }
 186
 187         /**
 188          * Returns true if the memory requirements of this object are getting large
 189          * @return bool
 190          */
 191         function isBig() {
 192                 global $wgLinkHolderBatchSize;
 193                 return $this->size > $wgLinkHolderBatchSize;
 194         }
 195
 196         /**
 197          * Clear all stored link holders.
 198          * Make sure you don't have any text left using these link holders, before you call this
 199          */
 200         function clear() {
 201                 $this->internals = array();
 202                 $this->interwikis = array();
 203                 $this->size = 0;
 204         }
 205
 206         /**
 207          * Make a link placeholder. The text returned can be later resolved to a real link with
 208          * replaceLinkHolders(). This is done for two reasons: firstly to avoid further
 209          * parsing of interwiki links, and secondly to allow all existence checks and
 210          * article length checks (for stub links) to be bundled into a single query.
 211          *
 212          * @param Title $nt
 213          * @param string $text
 214          * @param array $query [optional]
 215          * @param string $trail [optional]
 216          * @param string $prefix [optional]
 217          * @return string
 218          */
 219         function makeHolder( $nt, $text = '', $query = array(), $trail = '', $prefix = '' ) {
 220                 wfProfileIn( __METHOD__ );
 221                 if ( !is_object( $nt ) ) {
 222                         # Fail gracefully
 223                         $retVal = "<!-- ERROR -->{$prefix}{$text}{$trail}";
 224                 } else {
 225                         # Separate the link trail from the rest of the link
 226                         list( $inside, $trail ) = Linker::splitTrail( $trail );
 227
 228                         $entry = array(
 229                                 'title' => $nt,
 230                                 'text' => $prefix . $text . $inside,
 231                                 'pdbk' => $nt->getPrefixedDBkey(),
 232                         );
 233                         if ( $query !== array() ) {
 234                                 $entry['query'] = $query;
 235                         }
 236
 237                         if ( $nt->isExternal() ) {
 238                                 // Use a globally unique ID to keep the objects mergable
 239                                 $key = $this->parent->nextLinkID();
 240                                 $this->interwikis[$key] = $entry;
 241                                 $retVal = "<!--IWLINK $key-->{$trail}";
 242                         } else {
 243                                 $key = $this->parent->nextLinkID();
 244                                 $ns = $nt->getNamespace();
 245                                 $this->internals[$ns][$key] = $entry;
 246                                 $retVal = "<!--LINK $ns:$key-->{$trail}";
 247                         }
 248                         $this->size++;
 249                 }
 250                 wfProfileOut( __METHOD__ );
 251                 return $retVal;
 252         }
 253
 254         /**
 255          * Replace <!--LINK--> link placeholders with actual links, in the buffer
 256          *
 257          * @param $text
 258          * @return array Array of link CSS classes, indexed by PDBK.
 259          */
 260         function replace( &$text ) {
 261                 wfProfileIn( __METHOD__ );
 262
 263                 /** @todo FIXME: replaceInternal doesn't return a value */
 264                 $colours = $this->replaceInternal( $text );
 265                 $this->replaceInterwiki( $text );
 266
 267                 wfProfileOut( __METHOD__ );
 268                 return $colours;
 269         }
 270
 271         /**
 272          * Replace internal links
 273          * @param string $text
 274          */
 275         protected function replaceInternal( &$text ) {
 276                 if ( !$this->internals ) {
 277                         return;
 278                 }
 279
 280                 wfProfileIn( __METHOD__ );
 281                 global $wgContLang;
 282
 283                 $colours = array();
 284                 $linkCache = LinkCache::singleton();
 285                 $output = $this->parent->getOutput();
 286
 287                 wfProfileIn( __METHOD__ . '-check' );
 288                 $dbr = wfGetDB( DB_SLAVE );
 289                 $threshold = $this->parent->getOptions()->getStubThreshold();
 290
 291                 # Sort by namespace
 292                 ksort( $this->internals );
 293
 294                 $linkcolour_ids = array();
 295
 296                 # Generate query
 297                 $queries = array();
 298                 foreach ( $this->internals as $ns => $entries ) {
 299                         foreach ( $entries as $entry ) {
 300                                 $title = $entry['title'];
 301                                 $pdbk = $entry['pdbk'];
 302
 303                                 # Skip invalid entries.
 304                                 # Result will be ugly, but prevents crash.
 305                                 if ( is_null( $title ) ) {
 306                                         continue;
 307                                 }
 308
 309                                 # Check if it's a static known link, e.g. interwiki
 310                                 if ( $title->isAlwaysKnown() ) {
 311                                         $colours[$pdbk] = '';
 312                                 } elseif ( $ns == NS_SPECIAL ) {
 313                                         $colours[$pdbk] = 'new';
 314                                 } elseif ( ( $id = $linkCache->getGoodLinkID( $pdbk ) ) != 0 ) {
 315                                         $colours[$pdbk] = Linker::getLinkColour( $title, $threshold );
 316                                         $output->addLink( $title, $id );
 317                                         $linkcolour_ids[$id] = $pdbk;
 318                                 } elseif ( $linkCache->isBadLink( $pdbk ) ) {
 319                                         $colours[$pdbk] = 'new';
 320                                 } else {
 321                                         # Not in the link cache, add it to the query
 322                                         $queries[$ns][] = $title->getDBkey();
 323                                 }
 324                         }
 325                 }
 326                 if ( $queries ) {
 327                         $where = array();
 328                         foreach ( $queries as $ns => $pages ) {
 329                                 $where[] = $dbr->makeList(
 330                                         array(
 331                                                 'page_namespace' => $ns,
 332                                                 'page_title' => $pages,
 333                                         ),
 334                                         LIST_AND
 335                                 );
 336                         }
 337
 338                         $res = $dbr->select(
 339                                 'page',
 340                                 array( 'page_id', 'page_namespace', 'page_title',
 341                                         'page_is_redirect', 'page_len', 'page_latest' ),
 342                                 $dbr->makeList( $where, LIST_OR ),
 343                                 __METHOD__
 344                         );
 345
 346                         # Fetch data and form into an associative array
 347                         # non-existent = broken
 348                         foreach ( $res as $s ) {
 349                                 $title = Title::makeTitle( $s->page_namespace, $s->page_title );
 350                                 $pdbk = $title->getPrefixedDBkey();
 351                                 $linkCache->addGoodLinkObjFromRow( $title, $s );
 352                                 $output->addLink( $title, $s->page_id );
 353                                 # @todo FIXME: Convoluted data flow
 354                                 # The redirect status and length is passed to getLinkColour via the LinkCache
 355                                 # Use formal parameters instead
 356                                 $colours[$pdbk] = Linker::getLinkColour( $title, $threshold );
 357                                 //add id to the extension todolist
 358                                 $linkcolour_ids[$s->page_id] = $pdbk;
 359                         }
 360                         unset( $res );
 361                 }
 362                 if ( count( $linkcolour_ids ) ) {
 363                         //pass an array of page_ids to an extension
 364                         wfRunHooks( 'GetLinkColours', array( $linkcolour_ids, &$colours ) );
 365                 }
 366                 wfProfileOut( __METHOD__ . '-check' );
 367
 368                 # Do a second query for different language variants of links and categories
 369                 if ( $wgContLang->hasVariants() ) {
 370                         $this->doVariants( $colours );
 371                 }
 372
 373                 # Construct search and replace arrays
 374                 wfProfileIn( __METHOD__ . '-construct' );
 375                 $replacePairs = array();
 376                 foreach ( $this->internals as $ns => $entries ) {
 377                         foreach ( $entries as $index => $entry ) {
 378                                 $pdbk = $entry['pdbk'];
 379                                 $title = $entry['title'];
 380                                 $query = isset( $entry['query'] ) ? $entry['query'] : array();
 381                                 $key = "$ns:$index";
 382                                 $searchkey = "<!--LINK $key-->";
 383                                 $displayText = $entry['text'];
 384                                 if ( isset( $entry['selflink'] ) ) {
 385                                         $replacePairs[$searchkey] = Linker::makeSelfLinkObj( $title, $displayText, $query );
 386                                         continue;
 387                                 }
 388                                 if ( $displayText === '' ) {
 389                                         $displayText = null;
 390                                 }
 391                                 if ( !isset( $colours[$pdbk] ) ) {
 392                                         $colours[$pdbk] = 'new';
 393                                 }
 394                                 $attribs = array();
 395                                 if ( $colours[$pdbk] == 'new' ) {
 396                                         $linkCache->addBadLinkObj( $title );
 397                                         $output->addLink( $title, 0 );
 398                                         $type = array( 'broken' );
 399                                 } else {
 400                                         if ( $colours[$pdbk] != '' ) {
 401                                                 $attribs['class'] = $colours[$pdbk];
 402                                         }
 403                                         $type = array( 'known', 'noclasses' );
 404                                 }
 405                                 $replacePairs[$searchkey] = Linker::link( $title, $displayText,
 406                                                 $attribs, $query, $type );
 407                         }
 408                 }
 409                 $replacer = new HashtableReplacer( $replacePairs, 1 );
 410                 wfProfileOut( __METHOD__ . '-construct' );
 411
 412                 # Do the thing
 413                 wfProfileIn( __METHOD__ . '-replace' );
 414                 $text = preg_replace_callback(
 415                         '/(<!--LINK .*?-->)/',
 416                         $replacer->cb(),
 417                         $text
 418                 );
 419
 420                 wfProfileOut( __METHOD__ . '-replace' );
 421                 wfProfileOut( __METHOD__ );
 422         }
 423
 424         /**
 425          * Replace interwiki links
 426          * @param string $text
 427          */
 428         protected function replaceInterwiki( &$text ) {
 429                 if ( empty( $this->interwikis ) ) {
 430                         return;
 431                 }
 432
 433                 wfProfileIn( __METHOD__ );
 434                 # Make interwiki link HTML
 435                 $output = $this->parent->getOutput();
 436                 $replacePairs = array();
 437                 foreach ( $this->interwikis as $key => $link ) {
 438                         $replacePairs[$key] = Linker::link( $link['title'], $link['text'] );
 439                         $output->addInterwikiLink( $link['title'] );
 440                 }
 441                 $replacer = new HashtableReplacer( $replacePairs, 1 );
 442
 443                 $text = preg_replace_callback(
 444                         '/<!--IWLINK (.*?)-->/',
 445                         $replacer->cb(),
 446                         $text );
 447                 wfProfileOut( __METHOD__ );
 448         }
 449
 450         /**
 451          * Modify $this->internals and $colours according to language variant linking rules
 452          * @param array $colours
 453          */
 454         protected function doVariants( &$colours ) {
 455                 global $wgContLang;
 456                 $linkBatch = new LinkBatch();
 457                 $variantMap = array(); // maps $pdbkey_Variant => $keys (of link holders)
 458                 $output = $this->parent->getOutput();
 459                 $linkCache = LinkCache::singleton();
 460                 $threshold = $this->parent->getOptions()->getStubThreshold();
 461                 $titlesToBeConverted = '';
 462                 $titlesAttrs = array();
 463
 464                 // Concatenate titles to a single string, thus we only need auto convert the
 465                 // single string to all variants. This would improve parser's performance
 466                 // significantly.
 467                 foreach ( $this->internals as $ns => $entries ) {
 468                         if ( $ns == NS_SPECIAL ) {
 469                                 continue;
 470                         }
 471                         foreach ( $entries as $index => $entry ) {
 472                                 $pdbk = $entry['pdbk'];
 473                                 // we only deal with new links (in its first query)
 474                                 if ( !isset( $colours[$pdbk] ) || $colours[$pdbk] === 'new' ) {
 475                                         $titlesAttrs[] = array( $index, $entry['title'] );
 476                                         // separate titles with \0 because it would never appears
 477                                         // in a valid title
 478                                         $titlesToBeConverted .= $entry['title']->getText() . "\0";
 479                                 }
 480                         }
 481                 }
 482
 483                 // Now do the conversion and explode string to text of titles
 484                 $titlesAllVariants = $wgContLang->autoConvertToAllVariants( rtrim( $titlesToBeConverted, "\0" ) );
 485                 $allVariantsName = array_keys( $titlesAllVariants );
 486                 foreach ( $titlesAllVariants as &$titlesVariant ) {
 487                         $titlesVariant = explode( "\0", $titlesVariant );
 488                 }
 489
 490                 // Then add variants of links to link batch
 491                 $parentTitle = $this->parent->getTitle();
 492                 foreach ( $titlesAttrs as $i => $attrs ) {
 493                         list( $index, $title ) = $attrs;
 494                         $ns = $title->getNamespace();
 495                         $text = $title->getText();
 496
 497                         foreach ( $allVariantsName as $variantName ) {
 498                                 $textVariant = $titlesAllVariants[$variantName][$i];
 499                                 if ( $textVariant === $text ) {
 500                                         continue;
 501                                 }
 502
 503                                 $variantTitle = Title::makeTitle( $ns, $textVariant );
 504                                 if ( is_null( $variantTitle ) ) {
 505                                         continue;
 506                                 }
 507
 508                                 // Self-link checking for mixed/different variant titles. At this point, we
 509                                 // already know the exact title does not exist, so the link cannot be to a
 510                                 // variant of the current title that exists as a separate page.
 511                                 if ( $variantTitle->equals( $parentTitle ) && !$title->hasFragment() ) {
 512                                         $this->internals[$ns][$index]['selflink'] = true;
 513                                         continue 2;
 514                                 }
 515
 516                                 $linkBatch->addObj( $variantTitle );
 517                                 $variantMap[$variantTitle->getPrefixedDBkey()][] = "$ns:$index";
 518                         }
 519                 }
 520
 521                 // process categories, check if a category exists in some variant
 522                 $categoryMap = array(); // maps $category_variant => $category (dbkeys)
 523                 $varCategories = array(); // category replacements oldDBkey => newDBkey
 524                 foreach ( $output->getCategoryLinks() as $category ) {
 525                         $categoryTitle = Title::makeTitleSafe( NS_CATEGORY, $category );
 526                         $linkBatch->addObj( $categoryTitle );
 527                         $variants = $wgContLang->autoConvertToAllVariants( $category );
 528                         foreach ( $variants as $variant ) {
 529                                 if ( $variant !== $category ) {
 530                                         $variantTitle = Title::makeTitleSafe( NS_CATEGORY, $variant );
 531                                         if ( is_null( $variantTitle ) ) {
 532                                                 continue;
 533                                         }
 534                                         $linkBatch->addObj( $variantTitle );
 535                                         $categoryMap[$variant] = array( $category, $categoryTitle );
 536                                 }
 537                         }
 538                 }
 539
 540                 if ( !$linkBatch->isEmpty() ) {
 541                         // construct query
 542                         $dbr = wfGetDB( DB_SLAVE );
 543                         $varRes = $dbr->select( 'page',
 544                                 array( 'page_id', 'page_namespace', 'page_title',
 545                                         'page_is_redirect', 'page_len', 'page_latest' ),
 546                                 $linkBatch->constructSet( 'page', $dbr ),
 547                                 __METHOD__
 548                         );
 549
 550                         $linkcolour_ids = array();
 551
 552                         // for each found variants, figure out link holders and replace
 553                         foreach ( $varRes as $s ) {
 554
 555                                 $variantTitle = Title::makeTitle( $s->page_namespace, $s->page_title );
 556                                 $varPdbk = $variantTitle->getPrefixedDBkey();
 557                                 $vardbk = $variantTitle->getDBkey();
 558
 559                                 $holderKeys = array();
 560                                 if ( isset( $variantMap[$varPdbk] ) ) {
 561                                         $holderKeys = $variantMap[$varPdbk];
 562                                         $linkCache->addGoodLinkObjFromRow( $variantTitle, $s );
 563                                         $output->addLink( $variantTitle, $s->page_id );
 564                                 }
 565
 566                                 // loop over link holders
 567                                 foreach ( $holderKeys as $key ) {
 568                                         list( $ns, $index ) = explode( ':', $key, 2 );
 569                                         $entry =& $this->internals[$ns][$index];
 570                                         $pdbk = $entry['pdbk'];
 571
 572                                         if ( !isset( $colours[$pdbk] ) || $colours[$pdbk] === 'new' ) {
 573                                                 // found link in some of the variants, replace the link holder data
 574                                                 $entry['title'] = $variantTitle;
 575                                                 $entry['pdbk'] = $varPdbk;
 576
 577                                                 // set pdbk and colour
 578                                                 # @todo FIXME: Convoluted data flow
 579                                                 # The redirect status and length is passed to getLinkColour via the LinkCache
 580                                                 # Use formal parameters instead
 581                                                 $colours[$varPdbk] = Linker::getLinkColour( $variantTitle, $threshold );
 582                                                 $linkcolour_ids[$s->page_id] = $pdbk;
 583                                         }
 584                                 }
 585
 586                                 // check if the object is a variant of a category
 587                                 if ( isset( $categoryMap[$vardbk] ) ) {
 588                                         list( $oldkey, $oldtitle ) = $categoryMap[$vardbk];
 589                                         if ( !isset( $varCategories[$oldkey] ) && !$oldtitle->exists() ) {
 590                                                 $varCategories[$oldkey] = $vardbk;
 591                                         }
 592                                 }
 593                         }
 594                         wfRunHooks( 'GetLinkColours', array( $linkcolour_ids, &$colours ) );
 595
 596                         // rebuild the categories in original order (if there are replacements)
 597                         if ( count( $varCategories ) > 0 ) {
 598                                 $newCats = array();
 599                                 $originalCats = $output->getCategories();
 600                                 foreach ( $originalCats as $cat => $sortkey ) {
 601                                         // make the replacement
 602                                         if ( array_key_exists( $cat, $varCategories ) ) {
 603                                                 $newCats[$varCategories[$cat]] = $sortkey;
 604                                         } else {
 605                                                 $newCats[$cat] = $sortkey;
 606                                         }
 607                                 }
 608                                 $output->setCategoryLinks( $newCats );
 609                         }
 610                 }
 611         }
 612
 613         /**
 614          * Replace <!--LINK--> link placeholders with plain text of links
 615          * (not HTML-formatted).
 616          *
 617          * @param string $text
 618          * @return string
 619          */
 620         function replaceText( $text ) {
 621                 wfProfileIn( __METHOD__ );
 622
 623                 $text = preg_replace_callback(
 624                         '/<!--(LINK|IWLINK) (.*?)-->/',
 625                         array( &$this, 'replaceTextCallback' ),
 626                         $text );
 627
 628                 wfProfileOut( __METHOD__ );
 629                 return $text;
 630         }
 631
 632         /**
 633          * Callback for replaceText()
 634          *
 635          * @param array $matches
 636          * @return string
 637          * @private
 638          */
 639         function replaceTextCallback( $matches ) {
 640                 $type = $matches[1];
 641                 $key = $matches[2];
 642                 if ( $type == 'LINK' ) {
 643                         list( $ns, $index ) = explode( ':', $key, 2 );
 644                         if ( isset( $this->internals[$ns][$index]['text'] ) ) {
 645                                 return $this->internals[$ns][$index]['text'];
 646                         }
 647                 } elseif ( $type == 'IWLINK' ) {
 648                         if ( isset( $this->interwikis[$key]['text'] ) ) {
 649                                 return $this->interwikis[$key]['text'];
 650                         }
 651                 }
 652                 return $matches[0];
 653         }
 654 }