includes/specials/SpecialWhatlinkshere.php

   1 <?php
   2 /**
   3  * Implements Special:Whatlinkshere
   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  * @todo Use some variant of Pager or something; the pagination here is lousy.
  22  */
  23
  24 /**
  25  * Implements Special:Whatlinkshere
  26  *
  27  * @ingroup SpecialPage
  28  */
  29 class SpecialWhatLinksHere extends IncludableSpecialPage {
  30         /** @var FormOptions */
  31         protected $opts;
  32
  33         protected $selfTitle;
  34
  35         /** @var Title */
  36         protected $target;
  37
  38         protected $limits = array( 20, 50, 100, 250, 500 );
  39
  40         public function __construct() {
  41                 parent::__construct( 'Whatlinkshere' );
  42         }
  43
  44         function execute( $par ) {
  45                 $out = $this->getOutput();
  46
  47                 $this->setHeaders();
  48                 $this->outputHeader();
  49                 $this->addHelpLink( 'Help:What links here' );
  50
  51                 $opts = new FormOptions();
  52
  53                 $opts->add( 'target', '' );
  54                 $opts->add( 'namespace', '', FormOptions::INTNULL );
  55                 $opts->add( 'limit', $this->getConfig()->get( 'QueryPageDefaultLimit' ) );
  56                 $opts->add( 'from', 0 );
  57                 $opts->add( 'back', 0 );
  58                 $opts->add( 'hideredirs', false );
  59                 $opts->add( 'hidetrans', false );
  60                 $opts->add( 'hidelinks', false );
  61                 $opts->add( 'hideimages', false );
  62                 $opts->add( 'invert', false );
  63
  64                 $opts->fetchValuesFromRequest( $this->getRequest() );
  65                 $opts->validateIntBounds( 'limit', 0, 5000 );
  66
  67                 // Give precedence to subpage syntax
  68                 if ( $par !== null ) {
  69                         $opts->setValue( 'target', $par );
  70                 }
  71
  72                 // Bind to member variable
  73                 $this->opts = $opts;
  74
  75                 $this->target = Title::newFromURL( $opts->getValue( 'target' ) );
  76                 if ( !$this->target ) {
  77                         if ( !$this->including() ) {
  78                                 $out->addHTML( $this->whatlinkshereForm() );
  79                         }
  80
  81                         return;
  82                 }
  83
  84                 $this->getSkin()->setRelevantTitle( $this->target );
  85
  86                 $this->selfTitle = $this->getPageTitle( $this->target->getPrefixedDBkey() );
  87
  88                 $out->setPageTitle( $this->msg( 'whatlinkshere-title', $this->target->getPrefixedText() ) );
  89                 $out->addBacklinkSubtitle( $this->target );
  90                 $this->showIndirectLinks(
  91                         0,
  92                         $this->target,
  93                         $opts->getValue( 'limit' ),
  94                         $opts->getValue( 'from' ),
  95                         $opts->getValue( 'back' )
  96                 );
  97         }
  98
  99         /**
 100          * @param int $level Recursion level
 101          * @param Title $target Target title
 102          * @param int $limit Number of entries to display
 103          * @param int $from Display from this article ID (default: 0)
 104          * @param int $back Display from this article ID at backwards scrolling (default: 0)
 105          */
 106         function showIndirectLinks( $level, $target, $limit, $from = 0, $back = 0 ) {
 107                 $out = $this->getOutput();
 108                 $dbr = wfGetDB( DB_SLAVE );
 109
 110                 $hidelinks = $this->opts->getValue( 'hidelinks' );
 111                 $hideredirs = $this->opts->getValue( 'hideredirs' );
 112                 $hidetrans = $this->opts->getValue( 'hidetrans' );
 113                 $hideimages = $target->getNamespace() != NS_FILE || $this->opts->getValue( 'hideimages' );
 114
 115                 $fetchlinks = ( !$hidelinks || !$hideredirs );
 116
 117                 // Build query conds in concert for all three tables...
 118                 $conds['pagelinks'] = array(
 119                         'pl_namespace' => $target->getNamespace(),
 120                         'pl_title' => $target->getDBkey(),
 121                 );
 122                 $conds['templatelinks'] = array(
 123                         'tl_namespace' => $target->getNamespace(),
 124                         'tl_title' => $target->getDBkey(),
 125                 );
 126                 $conds['imagelinks'] = array(
 127                         'il_to' => $target->getDBkey(),
 128                 );
 129
 130                 $useLinkNamespaceDBFields = $this->getConfig()->get( 'UseLinkNamespaceDBFields' );
 131                 $namespace = $this->opts->getValue( 'namespace' );
 132                 $invert = $this->opts->getValue( 'invert' );
 133                 $nsComparison = ( $invert ? '!= ' : '= ' ) . $dbr->addQuotes( $namespace );
 134                 if ( is_int( $namespace ) ) {
 135                         if ( $useLinkNamespaceDBFields ) {
 136                                 $conds['pagelinks'][] = "pl_from_namespace $nsComparison";
 137                                 $conds['templatelinks'][] = "tl_from_namespace $nsComparison";
 138                                 $conds['imagelinks'][] = "il_from_namespace $nsComparison";
 139                         } else {
 140                                 $conds['pagelinks'][] = "page_namespace $nsComparison";
 141                                 $conds['templatelinks'][] = "page_namespace $nsComparison";
 142                                 $conds['imagelinks'][] = "page_namespace $nsComparison";
 143                         }
 144                 }
 145
 146                 if ( $from ) {
 147                         $conds['templatelinks'][] = "tl_from >= $from";
 148                         $conds['pagelinks'][] = "pl_from >= $from";
 149                         $conds['imagelinks'][] = "il_from >= $from";
 150                 }
 151
 152                 if ( $hideredirs ) {
 153                         $conds['pagelinks']['rd_from'] = null;
 154                 } elseif ( $hidelinks ) {
 155                         $conds['pagelinks'][] = 'rd_from is NOT NULL';
 156                 }
 157
 158                 $queryFunc = function ( $dbr, $table, $fromCol ) use (
 159                         $conds, $target, $limit, $useLinkNamespaceDBFields
 160                 ) {
 161                         // Read an extra row as an at-end check
 162                         $queryLimit = $limit + 1;
 163                         $on = array(
 164                                 "rd_from = $fromCol",
 165                                 'rd_title' => $target->getDBkey(),
 166                                 'rd_interwiki = ' . $dbr->addQuotes( '' ) . ' OR rd_interwiki IS NULL'
 167                         );
 168                         if ( $useLinkNamespaceDBFields ) { // migration check
 169                                 $on['rd_namespace'] = $target->getNamespace();
 170                         }
 171                         // Inner LIMIT is 2X in case of stale backlinks with wrong namespaces
 172                         $subQuery = $dbr->selectSqlText(
 173                                 array( $table, 'page', 'redirect' ),
 174                                 array( $fromCol, 'rd_from' ),
 175                                 $conds[$table],
 176                                 __CLASS__ . '::showIndirectLinks',
 177                                 array( 'ORDER BY' => $fromCol, 'LIMIT' => 2 * $queryLimit ),
 178                                 array(
 179                                         'page' => array( 'INNER JOIN', "$fromCol = page_id" ),
 180                                         'redirect' => array( 'LEFT JOIN', $on )
 181                                 )
 182                         );
 183                         return $dbr->select(
 184                                 array( 'page', 'temp_backlink_range' => "($subQuery)" ),
 185                                 array( 'page_id', 'page_namespace', 'page_title', 'rd_from', 'page_is_redirect' ),
 186                                 array(),
 187                                 __CLASS__ . '::showIndirectLinks',
 188                                 array( 'ORDER BY' => 'page_id', 'LIMIT' => $queryLimit ),
 189                                 array( 'page' => array( 'INNER JOIN', "$fromCol = page_id" ) )
 190                         );
 191                 };
 192
 193                 if ( $fetchlinks ) {
 194                         $plRes = $queryFunc( $dbr, 'pagelinks', 'pl_from' );
 195                 }
 196
 197                 if ( !$hidetrans ) {
 198                         $tlRes = $queryFunc( $dbr, 'templatelinks', 'tl_from' );
 199                 }
 200
 201                 if ( !$hideimages ) {
 202                         $ilRes = $queryFunc( $dbr, 'imagelinks', 'il_from' );
 203                 }
 204
 205                 if ( ( !$fetchlinks || !$plRes->numRows() )
 206                         && ( $hidetrans || !$tlRes->numRows() )
 207                         && ( $hideimages || !$ilRes->numRows() )
 208                 ) {
 209                         if ( 0 == $level ) {
 210                                 if ( !$this->including() ) {
 211                                         $out->addHTML( $this->whatlinkshereForm() );
 212
 213                                         // Show filters only if there are links
 214                                         if ( $hidelinks || $hidetrans || $hideredirs || $hideimages ) {
 215                                                 $out->addHTML( $this->getFilterPanel() );
 216                                         }
 217                                         $errMsg = is_int( $namespace ) ? 'nolinkshere-ns' : 'nolinkshere';
 218                                         $out->addWikiMsg( $errMsg, $this->target->getPrefixedText() );
 219                                         $out->setStatusCode( 404 );
 220                                 }
 221                         }
 222
 223                         return;
 224                 }
 225
 226                 // Read the rows into an array and remove duplicates
 227                 // templatelinks comes second so that the templatelinks row overwrites the
 228                 // pagelinks row, so we get (inclusion) rather than nothing
 229                 if ( $fetchlinks ) {
 230                         foreach ( $plRes as $row ) {
 231                                 $row->is_template = 0;
 232                                 $row->is_image = 0;
 233                                 $rows[$row->page_id] = $row;
 234                         }
 235                 }
 236                 if ( !$hidetrans ) {
 237                         foreach ( $tlRes as $row ) {
 238                                 $row->is_template = 1;
 239                                 $row->is_image = 0;
 240                                 $rows[$row->page_id] = $row;
 241                         }
 242                 }
 243                 if ( !$hideimages ) {
 244                         foreach ( $ilRes as $row ) {
 245                                 $row->is_template = 0;
 246                                 $row->is_image = 1;
 247                                 $rows[$row->page_id] = $row;
 248                         }
 249                 }
 250
 251                 // Sort by key and then change the keys to 0-based indices
 252                 ksort( $rows );
 253                 $rows = array_values( $rows );
 254
 255                 $numRows = count( $rows );
 256
 257                 // Work out the start and end IDs, for prev/next links
 258                 if ( $numRows > $limit ) {
 259                         // More rows available after these ones
 260                         // Get the ID from the last row in the result set
 261                         $nextId = $rows[$limit]->page_id;
 262                         // Remove undisplayed rows
 263                         $rows = array_slice( $rows, 0, $limit );
 264                 } else {
 265                         // No more rows after
 266                         $nextId = false;
 267                 }
 268                 $prevId = $from;
 269
 270                 // use LinkBatch to make sure, that all required data (associated with Titles)
 271                 // is loaded in one query
 272                 $lb = new LinkBatch();
 273                 foreach ( $rows as $row ) {
 274                         $lb->add( $row->page_namespace, $row->page_title );
 275                 }
 276                 $lb->execute();
 277
 278                 if ( $level == 0 ) {
 279                         if ( !$this->including() ) {
 280                                 $out->addHTML( $this->whatlinkshereForm() );
 281                                 $out->addHTML( $this->getFilterPanel() );
 282                                 $out->addWikiMsg( 'linkshere', $this->target->getPrefixedText() );
 283
 284                                 $prevnext = $this->getPrevNext( $prevId, $nextId );
 285                                 $out->addHTML( $prevnext );
 286                         }
 287                 }
 288                 $out->addHTML( $this->listStart( $level ) );
 289                 foreach ( $rows as $row ) {
 290                         $nt = Title::makeTitle( $row->page_namespace, $row->page_title );
 291
 292                         if ( $row->rd_from && $level < 2 ) {
 293                                 $out->addHTML( $this->listItem( $row, $nt, $target, true ) );
 294                                 $this->showIndirectLinks(
 295                                         $level + 1,
 296                                         $nt,
 297                                         $this->getConfig()->get( 'MaxRedirectLinksRetrieved' )
 298                                 );
 299                                 $out->addHTML( Xml::closeElement( 'li' ) );
 300                         } else {
 301                                 $out->addHTML( $this->listItem( $row, $nt, $target ) );
 302                         }
 303                 }
 304
 305                 $out->addHTML( $this->listEnd() );
 306
 307                 if ( $level == 0 ) {
 308                         if ( !$this->including() ) {
 309                                 $out->addHTML( $prevnext );
 310                         }
 311                 }
 312         }
 313
 314         protected function listStart( $level ) {
 315                 return Xml::openElement( 'ul', ( $level ? array() : array( 'id' => 'mw-whatlinkshere-list' ) ) );
 316         }
 317
 318         protected function listItem( $row, $nt, $target, $notClose = false ) {
 319                 $dirmark = $this->getLanguage()->getDirMark();
 320
 321                 # local message cache
 322                 static $msgcache = null;
 323                 if ( $msgcache === null ) {
 324                         static $msgs = array( 'isredirect', 'istemplate', 'semicolon-separator',
 325                                 'whatlinkshere-links', 'isimage', 'edit' );
 326                         $msgcache = array();
 327                         foreach ( $msgs as $msg ) {
 328                                 $msgcache[$msg] = $this->msg( $msg )->escaped();
 329                         }
 330                 }
 331
 332                 if ( $row->rd_from ) {
 333                         $query = array( 'redirect' => 'no' );
 334                 } else {
 335                         $query = array();
 336                 }
 337
 338                 $link = Linker::linkKnown(
 339                         $nt,
 340                         null,
 341                         $row->page_is_redirect ? array( 'class' => 'mw-redirect' ) : array(),
 342                         $query
 343                 );
 344
 345                 // Display properties (redirect or template)
 346                 $propsText = '';
 347                 $props = array();
 348                 if ( $row->rd_from ) {
 349                         $props[] = $msgcache['isredirect'];
 350                 }
 351                 if ( $row->is_template ) {
 352                         $props[] = $msgcache['istemplate'];
 353                 }
 354                 if ( $row->is_image ) {
 355                         $props[] = $msgcache['isimage'];
 356                 }
 357
 358                 Hooks::run( 'WhatLinksHereProps', array( $row, $nt, $target, &$props ) );
 359
 360                 if ( count( $props ) ) {
 361                         $propsText = $this->msg( 'parentheses' )
 362                                 ->rawParams( implode( $msgcache['semicolon-separator'], $props ) )->escaped();
 363                 }
 364
 365                 # Space for utilities links, with a what-links-here link provided
 366                 $wlhLink = $this->wlhLink( $nt, $msgcache['whatlinkshere-links'], $msgcache['edit'] );
 367                 $wlh = Xml::wrapClass(
 368                         $this->msg( 'parentheses' )->rawParams( $wlhLink )->escaped(),
 369                         'mw-whatlinkshere-tools'
 370                 );
 371
 372                 return $notClose ?
 373                         Xml::openElement( 'li' ) . "$link $propsText $dirmark $wlh\n" :
 374                         Xml::tags( 'li', null, "$link $propsText $dirmark $wlh" ) . "\n";
 375         }
 376
 377         protected function listEnd() {
 378                 return Xml::closeElement( 'ul' );
 379         }
 380
 381         protected function wlhLink( Title $target, $text, $editText ) {
 382                 static $title = null;
 383                 if ( $title === null ) {
 384                         $title = $this->getPageTitle();
 385                 }
 386
 387                 // always show a "<- Links" link
 388                 $links = array(
 389                         'links' => Linker::linkKnown(
 390                                 $title,
 391                                 $text,
 392                                 array(),
 393                                 array( 'target' => $target->getPrefixedText() )
 394                         ),
 395                 );
 396
 397                 // if the page is editable, add an edit link
 398                 if (
 399                         // check user permissions
 400                         $this->getUser()->isAllowed( 'edit' ) &&
 401                         // check, if the content model is editable through action=edit
 402                         ContentHandler::getForTitle( $target )->supportsDirectEditing()
 403                 ) {
 404                         $links['edit'] = Linker::linkKnown(
 405                                 $target,
 406                                 $editText,
 407                                 array(),
 408                                 array( 'action' => 'edit' )
 409                         );
 410                 }
 411
 412                 // build the links html
 413                 return $this->getLanguage()->pipeList( $links );
 414         }
 415
 416         function makeSelfLink( $text, $query ) {
 417                 return Linker::linkKnown(
 418                         $this->selfTitle,
 419                         $text,
 420                         array(),
 421                         $query
 422                 );
 423         }
 424
 425         function getPrevNext( $prevId, $nextId ) {
 426                 $currentLimit = $this->opts->getValue( 'limit' );
 427                 $prev = $this->msg( 'whatlinkshere-prev' )->numParams( $currentLimit )->escaped();
 428                 $next = $this->msg( 'whatlinkshere-next' )->numParams( $currentLimit )->escaped();
 429
 430                 $changed = $this->opts->getChangedValues();
 431                 unset( $changed['target'] ); // Already in the request title
 432
 433                 if ( 0 != $prevId ) {
 434                         $overrides = array( 'from' => $this->opts->getValue( 'back' ) );
 435                         $prev = $this->makeSelfLink( $prev, array_merge( $changed, $overrides ) );
 436                 }
 437                 if ( 0 != $nextId ) {
 438                         $overrides = array( 'from' => $nextId, 'back' => $prevId );
 439                         $next = $this->makeSelfLink( $next, array_merge( $changed, $overrides ) );
 440                 }
 441
 442                 $limitLinks = array();
 443                 $lang = $this->getLanguage();
 444                 foreach ( $this->limits as $limit ) {
 445                         $prettyLimit = htmlspecialchars( $lang->formatNum( $limit ) );
 446                         $overrides = array( 'limit' => $limit );
 447                         $limitLinks[] = $this->makeSelfLink( $prettyLimit, array_merge( $changed, $overrides ) );
 448                 }
 449
 450                 $nums = $lang->pipeList( $limitLinks );
 451
 452                 return $this->msg( 'viewprevnext' )->rawParams( $prev, $next, $nums )->escaped();
 453         }
 454
 455         function whatlinkshereForm() {
 456                 // We get nicer value from the title object
 457                 $this->opts->consumeValue( 'target' );
 458                 // Reset these for new requests
 459                 $this->opts->consumeValues( array( 'back', 'from' ) );
 460
 461                 $target = $this->target ? $this->target->getPrefixedText() : '';
 462                 $namespace = $this->opts->consumeValue( 'namespace' );
 463                 $nsinvert = $this->opts->consumeValue( 'invert' );
 464
 465                 # Build up the form
 466                 $f = Xml::openElement( 'form', array( 'action' => wfScript() ) );
 467
 468                 # Values that should not be forgotten
 469                 $f .= Html::hidden( 'title', $this->getPageTitle()->getPrefixedText() );
 470                 foreach ( $this->opts->getUnconsumedValues() as $name => $value ) {
 471                         $f .= Html::hidden( $name, $value );
 472                 }
 473
 474                 $f .= Xml::fieldset( $this->msg( 'whatlinkshere' )->text() );
 475
 476                 # Target input (.mw-searchInput enables suggestions)
 477                 $f .= Xml::inputLabel( $this->msg( 'whatlinkshere-page' )->text(), 'target',
 478                         'mw-whatlinkshere-target', 40, $target, array( 'class' => 'mw-searchInput' ) );
 479
 480                 $f .= ' ';
 481
 482                 # Namespace selector
 483                 $f .= Html::namespaceSelector(
 484                         array(
 485                                 'selected' => $namespace,
 486                                 'all' => '',
 487                                 'label' => $this->msg( 'namespace' )->text()
 488                         ), array(
 489                                 'name' => 'namespace',
 490                                 'id' => 'namespace',
 491                                 'class' => 'namespaceselector',
 492                         )
 493                 );
 494
 495                 $f .= '&#160;' .
 496                         Xml::checkLabel(
 497                                 $this->msg( 'invert' )->text(),
 498                                 'invert',
 499                                 'nsinvert',
 500                                 $nsinvert,
 501                                 array( 'title' => $this->msg( 'tooltip-whatlinkshere-invert' )->text() )
 502                         );
 503
 504                 $f .= ' ';
 505
 506                 # Submit
 507                 $f .= Xml::submitButton( $this->msg( 'allpagessubmit' )->text() );
 508
 509                 # Close
 510                 $f .= Xml::closeElement( 'fieldset' ) . Xml::closeElement( 'form' ) . "\n";
 511
 512                 return $f;
 513         }
 514
 515         /**
 516          * Create filter panel
 517          *
 518          * @return string HTML fieldset and filter panel with the show/hide links
 519          */
 520         function getFilterPanel() {
 521                 $show = $this->msg( 'show' )->escaped();
 522                 $hide = $this->msg( 'hide' )->escaped();
 523
 524                 $changed = $this->opts->getChangedValues();
 525                 unset( $changed['target'] ); // Already in the request title
 526
 527                 $links = array();
 528                 $types = array( 'hidetrans', 'hidelinks', 'hideredirs' );
 529                 if ( $this->target->getNamespace() == NS_FILE ) {
 530                         $types[] = 'hideimages';
 531                 }
 532
 533                 // Combined message keys: 'whatlinkshere-hideredirs', 'whatlinkshere-hidetrans',
 534                 // 'whatlinkshere-hidelinks', 'whatlinkshere-hideimages'
 535                 // To be sure they will be found by grep
 536                 foreach ( $types as $type ) {
 537                         $chosen = $this->opts->getValue( $type );
 538                         $msg = $chosen ? $show : $hide;
 539                         $overrides = array( $type => !$chosen );
 540                         $links[] = $this->msg( "whatlinkshere-{$type}" )->rawParams(
 541                                 $this->makeSelfLink( $msg, array_merge( $changed, $overrides ) ) )->escaped();
 542                 }
 543
 544                 return Xml::fieldset(
 545                         $this->msg( 'whatlinkshere-filters' )->text(),
 546                         $this->getLanguage()->pipeList( $links )
 547                 );
 548         }
 549
 550         /**
 551          * Return an array of subpages beginning with $search that this special page will accept.
 552          *
 553          * @param string $search Prefix to search for
 554          * @param int $limit Maximum number of results to return (usually 10)
 555          * @param int $offset Number of results to skip (usually 0)
 556          * @return string[] Matching subpages
 557          */
 558         public function prefixSearchSubpages( $search, $limit, $offset ) {
 559                 if ( $search === '' ) {
 560                         return array();
 561                 }
 562                 // Autocomplete subpage the same as a normal search
 563                 $prefixSearcher = new StringPrefixSearch;
 564                 $result = $prefixSearcher->search( $search, $limit, array(), $offset );
 565                 return $result;
 566         }
 567
 568         protected function getGroupName() {
 569                 return 'pagetools';
 570         }
 571 }