includes/actions/HistoryAction.php

   1 <?php
   2 /**
   3  * Page history
   4  *
   5  * Split off from Article.php and Skin.php, 2003-12-22
   6  *
   7  * This program is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License as published by
   9  * the Free Software Foundation; either version 2 of the License, or
  10  * (at your option) any later version.
  11  *
  12  * This program is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  15  * GNU General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU General Public License along
  18  * with this program; if not, write to the Free Software Foundation, Inc.,
  19  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  20  * http://www.gnu.org/copyleft/gpl.html
  21  *
  22  * @file
  23  * @ingroup Actions
  24  */
  25
  26 /**
  27  * This class handles printing the history page for an article. In order to
  28  * be efficient, it uses timestamps rather than offsets for paging, to avoid
  29  * costly LIMIT,offset queries.
  30  *
  31  * Construct it by passing in an Article, and call $h->history() to print the
  32  * history.
  33  *
  34  * @ingroup Actions
  35  */
  36 class HistoryAction extends FormlessAction {
  37         const DIR_PREV = 0;
  38         const DIR_NEXT = 1;
  39
  40         /** @var array Array of message keys and strings */
  41         public $message;
  42
  43         public function getName() {
  44                 return 'history';
  45         }
  46
  47         public function requiresWrite() {
  48                 return false;
  49         }
  50
  51         public function requiresUnblock() {
  52                 return false;
  53         }
  54
  55         protected function getPageTitle() {
  56                 return $this->msg( 'history-title', $this->getTitle()->getPrefixedText() )->text();
  57         }
  58
  59         protected function getDescription() {
  60                 // Creation of a subtitle link pointing to [[Special:Log]]
  61                 return Linker::linkKnown(
  62                         SpecialPage::getTitleFor( 'Log' ),
  63                         $this->msg( 'viewpagelogs' )->escaped(),
  64                         array(),
  65                         array( 'page' => $this->getTitle()->getPrefixedText() )
  66                 );
  67         }
  68
  69         /**
  70          * Get the Article object we are working on.
  71          * @return Page
  72          */
  73         public function getArticle() {
  74                 return $this->page;
  75         }
  76
  77         /**
  78          * As we use the same small set of messages in various methods and that
  79          * they are called often, we call them once and save them in $this->message
  80          */
  81         private function preCacheMessages() {
  82                 // Precache various messages
  83                 if ( !isset( $this->message ) ) {
  84                         $msgs = array( 'cur', 'last', 'pipe-separator' );
  85                         foreach ( $msgs as $msg ) {
  86                                 $this->message[$msg] = $this->msg( $msg )->escaped();
  87                         }
  88                 }
  89         }
  90
  91         /**
  92          * Print the history page for an article.
  93          */
  94         function onView() {
  95                 $out = $this->getOutput();
  96                 $request = $this->getRequest();
  97
  98                 /**
  99                  * Allow client caching.
 100                  */
 101                 if ( $out->checkLastModified( $this->page->getTouched() ) ) {
 102                         return; // Client cache fresh and headers sent, nothing more to do.
 103                 }
 104
 105                 wfProfileIn( __METHOD__ );
 106
 107                 $this->preCacheMessages();
 108                 $config = $this->context->getConfig();
 109
 110                 # Fill in the file cache if not set already
 111                 $useFileCache = $config->get( 'UseFileCache' );
 112                 if ( $useFileCache && HTMLFileCache::useFileCache( $this->getContext() ) ) {
 113                         $cache = new HTMLFileCache( $this->getTitle(), 'history' );
 114                         if ( !$cache->isCacheGood( /* Assume up to date */ ) ) {
 115                                 ob_start( array( &$cache, 'saveToFileCache' ) );
 116                         }
 117                 }
 118
 119                 // Setup page variables.
 120                 $out->setFeedAppendQuery( 'action=history' );
 121                 $out->addModules( 'mediawiki.action.history' );
 122                 if ( $config->get( 'UseMediaWikiUIEverywhere' ) ) {
 123                         $out = $this->getOutput();
 124                         $out->addModuleStyles( array(
 125                                 'mediawiki.ui.input',
 126                                 'mediawiki.ui.checkbox',
 127                         ) );
 128                 }
 129
 130                 // Handle atom/RSS feeds.
 131                 $feedType = $request->getVal( 'feed' );
 132                 if ( $feedType ) {
 133                         $this->feed( $feedType );
 134                         wfProfileOut( __METHOD__ );
 135
 136                         return;
 137                 }
 138
 139                 // Fail nicely if article doesn't exist.
 140                 if ( !$this->page->exists() ) {
 141                         $out->addWikiMsg( 'nohistory' );
 142                         # show deletion/move log if there is an entry
 143                         LogEventsList::showLogExtract(
 144                                 $out,
 145                                 array( 'delete', 'move' ),
 146                                 $this->getTitle(),
 147                                 '',
 148                                 array( 'lim' => 10,
 149                                         'conds' => array( "log_action != 'revision'" ),
 150                                         'showIfEmpty' => false,
 151                                         'msgKey' => array( 'moveddeleted-notice' )
 152                                 )
 153                         );
 154                         wfProfileOut( __METHOD__ );
 155
 156                         return;
 157                 }
 158
 159                 /**
 160                  * Add date selector to quickly get to a certain time
 161                  */
 162                 $year = $request->getInt( 'year' );
 163                 $month = $request->getInt( 'month' );
 164                 $tagFilter = $request->getVal( 'tagfilter' );
 165                 $tagSelector = ChangeTags::buildTagFilterSelector( $tagFilter );
 166
 167                 /**
 168                  * Option to show only revisions that have been (partially) hidden via RevisionDelete
 169                  */
 170                 if ( $request->getBool( 'deleted' ) ) {
 171                         $conds = array( 'rev_deleted != 0' );
 172                 } else {
 173                         $conds = array();
 174                 }
 175                 if ( $this->getUser()->isAllowed( 'deletedhistory' ) ) {
 176                         $checkDeleted = Xml::checkLabel( $this->msg( 'history-show-deleted' )->text(),
 177                                 'deleted', 'mw-show-deleted-only', $request->getBool( 'deleted' ) ) . "\n";
 178                 } else {
 179                         $checkDeleted = '';
 180                 }
 181
 182                 // Add the general form
 183                 $action = htmlspecialchars( wfScript() );
 184                 $className = 'historysubmit mw-history-compareselectedversions-button';
 185                 $out->addHTML(
 186                         "<form action=\"$action\" method=\"get\" id=\"mw-history-searchform\">" .
 187                         Xml::fieldset(
 188                                 $this->msg( 'history-fieldset-title' )->text(),
 189                                 false,
 190                                 array( 'id' => 'mw-history-search' )
 191                         ) .
 192                         Html::hidden( 'title', $this->getTitle()->getPrefixedDBkey() ) . "\n" .
 193                         Html::hidden( 'action', 'history' ) . "\n" .
 194                         Xml::dateMenu(
 195                                 ( $year == null ? MWTimestamp::getLocalInstance()->format( 'Y' ) : $year ),
 196                                 $month
 197                         ) . '&#160;' .
 198                         ( $tagSelector ? ( implode( '&#160;', $tagSelector ) . '&#160;' ) : '' ) .
 199                         $checkDeleted .
 200                         Html::submitButton(
 201                                 $this->msg( 'allpagessubmit' )->text(),
 202                                 $attrs,
 203                                 array( 'mw-ui-progressive' )
 204                         ) . "\n" .
 205                         '</fieldset></form>'
 206                 );
 207
 208                 wfRunHooks( 'PageHistoryBeforeList', array( &$this->page, $this->getContext() ) );
 209
 210                 // Create and output the list.
 211                 $pager = new HistoryPager( $this, $year, $month, $tagFilter, $conds );
 212                 $out->addHTML(
 213                         $pager->getNavigationBar() .
 214                         $pager->getBody() .
 215                         $pager->getNavigationBar()
 216                 );
 217                 $out->preventClickjacking( $pager->getPreventClickjacking() );
 218
 219                 wfProfileOut( __METHOD__ );
 220         }
 221
 222         /**
 223          * Fetch an array of revisions, specified by a given limit, offset and
 224          * direction. This is now only used by the feeds. It was previously
 225          * used by the main UI but that's now handled by the pager.
 226          *
 227          * @param int $limit The limit number of revisions to get
 228          * @param int $offset
 229          * @param int $direction Either self::DIR_PREV or self::DIR_NEXT
 230          * @return ResultWrapper
 231          */
 232         function fetchRevisions( $limit, $offset, $direction ) {
 233                 // Fail if article doesn't exist.
 234                 if ( !$this->getTitle()->exists() ) {
 235                         return new FakeResultWrapper( array() );
 236                 }
 237
 238                 $dbr = wfGetDB( DB_SLAVE );
 239
 240                 if ( $direction === self::DIR_PREV ) {
 241                         list( $dirs, $oper ) = array( "ASC", ">=" );
 242                 } else { /* $direction === self::DIR_NEXT */
 243                         list( $dirs, $oper ) = array( "DESC", "<=" );
 244                 }
 245
 246                 if ( $offset ) {
 247                         $offsets = array( "rev_timestamp $oper " . $dbr->addQuotes( $dbr->timestamp( $offset ) ) );
 248                 } else {
 249                         $offsets = array();
 250                 }
 251
 252                 $page_id = $this->page->getId();
 253
 254                 return $dbr->select( 'revision',
 255                         Revision::selectFields(),
 256                         array_merge( array( 'rev_page' => $page_id ), $offsets ),
 257                         __METHOD__,
 258                         array( 'ORDER BY' => "rev_timestamp $dirs",
 259                                 'USE INDEX' => 'page_timestamp', 'LIMIT' => $limit )
 260                 );
 261         }
 262
 263         /**
 264          * Output a subscription feed listing recent edits to this page.
 265          *
 266          * @param string $type Feed type
 267          */
 268         function feed( $type ) {
 269                 if ( !FeedUtils::checkFeedOutput( $type ) ) {
 270                         return;
 271                 }
 272                 $request = $this->getRequest();
 273
 274                 $feedClasses = $this->context->getConfig()->get( 'FeedClasses' );
 275                 /** @var RSSFeed|AtomFeed $feed */
 276                 $feed = new $feedClasses[$type](
 277                         $this->getTitle()->getPrefixedText() . ' - ' .
 278                         $this->msg( 'history-feed-title' )->inContentLanguage()->text(),
 279                         $this->msg( 'history-feed-description' )->inContentLanguage()->text(),
 280                         $this->getTitle()->getFullURL( 'action=history' )
 281                 );
 282
 283                 // Get a limit on number of feed entries. Provide a sane default
 284                 // of 10 if none is defined (but limit to $wgFeedLimit max)
 285                 $limit = $request->getInt( 'limit', 10 );
 286                 $limit = min(
 287                         max( $limit, 1 ),
 288                         $this->context->getConfig()->get( 'FeedLimit' )
 289                 );
 290
 291                 $items = $this->fetchRevisions( $limit, 0, self::DIR_NEXT );
 292
 293                 // Generate feed elements enclosed between header and footer.
 294                 $feed->outHeader();
 295                 if ( $items->numRows() ) {
 296                         foreach ( $items as $row ) {
 297                                 $feed->outItem( $this->feedItem( $row ) );
 298                         }
 299                 } else {
 300                         $feed->outItem( $this->feedEmpty() );
 301                 }
 302                 $feed->outFooter();
 303         }
 304
 305         function feedEmpty() {
 306                 return new FeedItem(
 307                         $this->msg( 'nohistory' )->inContentLanguage()->text(),
 308                         $this->msg( 'history-feed-empty' )->inContentLanguage()->parseAsBlock(),
 309                         $this->getTitle()->getFullURL(),
 310                         wfTimestamp( TS_MW ),
 311                         '',
 312                         $this->getTitle()->getTalkPage()->getFullURL()
 313                 );
 314         }
 315
 316         /**
 317          * Generate a FeedItem object from a given revision table row
 318          * Borrows Recent Changes' feed generation functions for formatting;
 319          * includes a diff to the previous revision (if any).
 320          *
 321          * @param stdClass|array $row Database row
 322          * @return FeedItem
 323          */
 324         function feedItem( $row ) {
 325                 $rev = new Revision( $row );
 326                 $rev->setTitle( $this->getTitle() );
 327                 $text = FeedUtils::formatDiffRow(
 328                         $this->getTitle(),
 329                         $this->getTitle()->getPreviousRevisionID( $rev->getId() ),
 330                         $rev->getId(),
 331                         $rev->getTimestamp(),
 332                         $rev->getComment()
 333                 );
 334                 if ( $rev->getComment() == '' ) {
 335                         global $wgContLang;
 336                         $title = $this->msg( 'history-feed-item-nocomment',
 337                                 $rev->getUserText(),
 338                                 $wgContLang->timeanddate( $rev->getTimestamp() ),
 339                                 $wgContLang->date( $rev->getTimestamp() ),
 340                                 $wgContLang->time( $rev->getTimestamp() ) )->inContentLanguage()->text();
 341                 } else {
 342                         $title = $rev->getUserText() .
 343                                 $this->msg( 'colon-separator' )->inContentLanguage()->text() .
 344                                 FeedItem::stripComment( $rev->getComment() );
 345                 }
 346
 347                 return new FeedItem(
 348                         $title,
 349                         $text,
 350                         $this->getTitle()->getFullURL( 'diff=' . $rev->getId() . '&oldid=prev' ),
 351                         $rev->getTimestamp(),
 352                         $rev->getUserText(),
 353                         $this->getTitle()->getTalkPage()->getFullURL()
 354                 );
 355         }
 356 }
 357
 358 /**
 359  * @ingroup Pager
 360  * @ingroup Actions
 361  */
 362 class HistoryPager extends ReverseChronologicalPager {
 363         /**
 364          * @var bool|stdClass
 365          */
 366         public $lastRow = false;
 367
 368         public $counter, $historyPage, $buttons, $conds;
 369
 370         protected $oldIdChecked;
 371
 372         protected $preventClickjacking = false;
 373         /**
 374          * @var array
 375          */
 376         protected $parentLens;
 377
 378         /**
 379          * @param HistoryAction $historyPage
 380          * @param string $year
 381          * @param string $month
 382          * @param string $tagFilter
 383          * @param array $conds
 384          */
 385         function __construct( $historyPage, $year = '', $month = '', $tagFilter = '', $conds = array() ) {
 386                 parent::__construct( $historyPage->getContext() );
 387                 $this->historyPage = $historyPage;
 388                 $this->tagFilter = $tagFilter;
 389                 $this->getDateCond( $year, $month );
 390                 $this->conds = $conds;
 391         }
 392
 393         // For hook compatibility...
 394         function getArticle() {
 395                 return $this->historyPage->getArticle();
 396         }
 397
 398         function getSqlComment() {
 399                 if ( $this->conds ) {
 400                         return 'history page filtered'; // potentially slow, see CR r58153
 401                 } else {
 402                         return 'history page unfiltered';
 403                 }
 404         }
 405
 406         function getQueryInfo() {
 407                 $queryInfo = array(
 408                         'tables' => array( 'revision', 'user' ),
 409                         'fields' => array_merge( Revision::selectFields(), Revision::selectUserFields() ),
 410                         'conds' => array_merge(
 411                                 array( 'rev_page' => $this->getWikiPage()->getId() ),
 412                                 $this->conds ),
 413                         'options' => array( 'USE INDEX' => array( 'revision' => 'page_timestamp' ) ),
 414                         'join_conds' => array( 'user' => Revision::userJoinCond() ),
 415                 );
 416                 ChangeTags::modifyDisplayQuery(
 417                         $queryInfo['tables'],
 418                         $queryInfo['fields'],
 419                         $queryInfo['conds'],
 420                         $queryInfo['join_conds'],
 421                         $queryInfo['options'],
 422                         $this->tagFilter
 423                 );
 424                 wfRunHooks( 'PageHistoryPager::getQueryInfo', array( &$this, &$queryInfo ) );
 425
 426                 return $queryInfo;
 427         }
 428
 429         function getIndexField() {
 430                 return 'rev_timestamp';
 431         }
 432
 433         /**
 434          * @param stdClass $row
 435          * @return string
 436          */
 437         function formatRow( $row ) {
 438                 if ( $this->lastRow ) {
 439                         $latest = ( $this->counter == 1 && $this->mIsFirst );
 440                         $firstInList = $this->counter == 1;
 441                         $this->counter++;
 442                         $s = $this->historyLine( $this->lastRow, $row,
 443                                 $this->getTitle()->getNotificationTimestamp( $this->getUser() ), $latest, $firstInList );
 444                 } else {
 445                         $s = '';
 446                 }
 447                 $this->lastRow = $row;
 448
 449                 return $s;
 450         }
 451
 452         function doBatchLookups() {
 453                 # Do a link batch query
 454                 $this->mResult->seek( 0 );
 455                 $batch = new LinkBatch();
 456                 $revIds = array();
 457                 foreach ( $this->mResult as $row ) {
 458                         if ( $row->rev_parent_id ) {
 459                                 $revIds[] = $row->rev_parent_id;
 460                         }
 461                         if ( !is_null( $row->user_name ) ) {
 462                                 $batch->add( NS_USER, $row->user_name );
 463                                 $batch->add( NS_USER_TALK, $row->user_name );
 464                         } else { # for anons or usernames of imported revisions
 465                                 $batch->add( NS_USER, $row->rev_user_text );
 466                                 $batch->add( NS_USER_TALK, $row->rev_user_text );
 467                         }
 468                 }
 469                 $this->parentLens = Revision::getParentLengths( $this->mDb, $revIds );
 470                 $batch->execute();
 471                 $this->mResult->seek( 0 );
 472         }
 473
 474         /**
 475          * Creates begin of history list with a submit button
 476          *
 477          * @return string HTML output
 478          */
 479         function getStartBody() {
 480                 $this->lastRow = false;
 481                 $this->counter = 1;
 482                 $this->oldIdChecked = 0;
 483
 484                 $this->getOutput()->wrapWikiMsg( "<div class='mw-history-legend'>\n$1\n</div>", 'histlegend' );
 485                 $s = Html::openElement( 'form', array( 'action' => wfScript(),
 486                         'id' => 'mw-history-compare' ) ) . "\n";
 487                 $s .= Html::hidden( 'title', $this->getTitle()->getPrefixedDBkey() ) . "\n";
 488                 $s .= Html::hidden( 'action', 'historysubmit' ) . "\n";
 489
 490                 // Button container stored in $this->buttons for re-use in getEndBody()
 491                 $this->buttons = '<div>';
 492                 $className = 'historysubmit mw-history-compareselectedversions-button';
 493                 $attrs = array( 'class' => $className )
 494                         + Linker::tooltipAndAccesskeyAttribs( 'compareselectedversions' );
 495                 $this->buttons .= $this->submitButton( $this->msg( 'compareselectedversions' )->text(),
 496                         $attrs
 497                 ) . "\n";
 498
 499                 if ( $this->getUser()->isAllowed( 'deleterevision' ) ) {
 500                         $this->buttons .= $this->getRevisionButton( 'revisiondelete', 'showhideselectedversions' );
 501                 }
 502                 $this->buttons .= '</div>';
 503
 504                 $s .= $this->buttons;
 505                 $s .= '<ul id="pagehistory">' . "\n";
 506
 507                 return $s;
 508         }
 509
 510         private function getRevisionButton( $name, $msg ) {
 511                 $this->preventClickjacking();
 512                 # Note bug #20966, <button> is non-standard in IE<8
 513                 $element = Html::element(
 514                         'button',
 515                         array(
 516                                 'type' => 'submit',
 517                                 'name' => $name,
 518                                 'value' => '1',
 519                                 'class' => "historysubmit mw-history-$name-button",
 520                         ),
 521                         $this->msg( $msg )->text()
 522                 ) . "\n";
 523                 return $element;
 524         }
 525
 526         function getEndBody() {
 527                 if ( $this->lastRow ) {
 528                         $latest = $this->counter == 1 && $this->mIsFirst;
 529                         $firstInList = $this->counter == 1;
 530                         if ( $this->mIsBackwards ) {
 531                                 # Next row is unknown, but for UI reasons, probably exists if an offset has been specified
 532                                 if ( $this->mOffset == '' ) {
 533                                         $next = null;
 534                                 } else {
 535                                         $next = 'unknown';
 536                                 }
 537                         } else {
 538                                 # The next row is the past-the-end row
 539                                 $next = $this->mPastTheEndRow;
 540                         }
 541                         $this->counter++;
 542                         $s = $this->historyLine( $this->lastRow, $next,
 543                                 $this->getTitle()->getNotificationTimestamp( $this->getUser() ), $latest, $firstInList );
 544                 } else {
 545                         $s = '';
 546                 }
 547                 $s .= "</ul>\n";
 548                 # Add second buttons only if there is more than one rev
 549                 if ( $this->getNumRows() > 2 ) {
 550                         $s .= $this->buttons;
 551                 }
 552                 $s .= '</form>';
 553
 554                 return $s;
 555         }
 556
 557         /**
 558          * Creates a submit button
 559          *
 560          * @param string $message Text of the submit button, will be escaped
 561          * @param array $attributes Attributes
 562          * @return string HTML output for the submit button
 563          */
 564         function submitButton( $message, $attributes = array() ) {
 565                 # Disable submit button if history has 1 revision only
 566                 if ( $this->getNumRows() > 1 ) {
 567                         return Html::submitButton( $message, $attributes );
 568                 } else {
 569                         return '';
 570                 }
 571         }
 572
 573         /**
 574          * Returns a row from the history printout.
 575          *
 576          * @todo document some more, and maybe clean up the code (some params redundant?)
 577          *
 578          * @param stdClass $row The database row corresponding to the previous line.
 579          * @param mixed $next The database row corresponding to the next line
 580          *   (chronologically previous)
 581          * @param bool|string $notificationtimestamp
 582          * @param bool $latest Whether this row corresponds to the page's latest revision.
 583          * @param bool $firstInList Whether this row corresponds to the first
 584          *   displayed on this history page.
 585          * @return string HTML output for the row
 586          */
 587         function historyLine( $row, $next, $notificationtimestamp = false,
 588                 $latest = false, $firstInList = false ) {
 589                 $rev = new Revision( $row );
 590                 $rev->setTitle( $this->getTitle() );
 591
 592                 if ( is_object( $next ) ) {
 593                         $prevRev = new Revision( $next );
 594                         $prevRev->setTitle( $this->getTitle() );
 595                 } else {
 596                         $prevRev = null;
 597                 }
 598
 599                 $curlink = $this->curLink( $rev, $latest );
 600                 $lastlink = $this->lastLink( $rev, $next );
 601                 $curLastlinks = $curlink . $this->historyPage->message['pipe-separator'] . $lastlink;
 602                 $histLinks = Html::rawElement(
 603                         'span',
 604                         array( 'class' => 'mw-history-histlinks' ),
 605                         $this->msg( 'parentheses' )->rawParams( $curLastlinks )->escaped()
 606                 );
 607
 608                 $diffButtons = $this->diffButtons( $rev, $firstInList );
 609                 $s = $histLinks . $diffButtons;
 610
 611                 $link = $this->revLink( $rev );
 612                 $classes = array();
 613
 614                 $del = '';
 615                 $user = $this->getUser();
 616                 // Show checkboxes for each revision
 617                 if ( $user->isAllowed( 'deleterevision' ) ) {
 618                         $this->preventClickjacking();
 619                         // If revision was hidden from sysops, disable the checkbox
 620                         if ( !$rev->userCan( Revision::DELETED_RESTRICTED, $user ) ) {
 621                                 $del = Xml::check( 'deleterevisions', false, array( 'disabled' => 'disabled' ) );
 622                         // Otherwise, enable the checkbox...
 623                         } else {
 624                                 $del = Xml::check( 'showhiderevisions', false,
 625                                         array( 'name' => 'ids[' . $rev->getId() . ']' ) );
 626                         }
 627                 // User can only view deleted revisions...
 628                 } elseif ( $rev->getVisibility() && $user->isAllowed( 'deletedhistory' ) ) {
 629                         // If revision was hidden from sysops, disable the link
 630                         if ( !$rev->userCan( Revision::DELETED_RESTRICTED, $user ) ) {
 631                                 $del = Linker::revDeleteLinkDisabled( false );
 632                         // Otherwise, show the link...
 633                         } else {
 634                                 $query = array( 'type' => 'revision',
 635                                         'target' => $this->getTitle()->getPrefixedDBkey(), 'ids' => $rev->getId() );
 636                                 $del .= Linker::revDeleteLink( $query,
 637                                         $rev->isDeleted( Revision::DELETED_RESTRICTED ), false );
 638                         }
 639                 }
 640                 if ( $del ) {
 641                         $s .= " $del ";
 642                 }
 643
 644                 $lang = $this->getLanguage();
 645                 $dirmark = $lang->getDirMark();
 646
 647                 $s .= " $link";
 648                 $s .= $dirmark;
 649                 $s .= " <span class='history-user'>" .
 650                         Linker::revUserTools( $rev, true ) . "</span>";
 651                 $s .= $dirmark;
 652
 653                 if ( $rev->isMinor() ) {
 654                         $s .= ' ' . ChangesList::flag( 'minor' );
 655                 }
 656
 657                 # Sometimes rev_len isn't populated
 658                 if ( $rev->getSize() !== null ) {
 659                         # Size is always public data
 660                         $prevSize = isset( $this->parentLens[$row->rev_parent_id] )
 661                                 ? $this->parentLens[$row->rev_parent_id]
 662                                 : 0;
 663                         $sDiff = ChangesList::showCharacterDifference( $prevSize, $rev->getSize() );
 664                         $fSize = Linker::formatRevisionSize( $rev->getSize() );
 665                         $s .= ' <span class="mw-changeslist-separator">. .</span> ' . "$fSize $sDiff";
 666                 }
 667
 668                 # Text following the character difference is added just before running hooks
 669                 $s2 = Linker::revComment( $rev, false, true );
 670
 671                 if ( $notificationtimestamp && ( $row->rev_timestamp >= $notificationtimestamp ) ) {
 672                         $s2 .= ' <span class="updatedmarker">' . $this->msg( 'updatedmarker' )->escaped() . '</span>';
 673                         $classes[] = 'mw-history-line-updated';
 674                 }
 675
 676                 $tools = array();
 677
 678                 # Rollback and undo links
 679                 if ( $prevRev && $this->getTitle()->quickUserCan( 'edit', $user ) ) {
 680                         if ( $latest && $this->getTitle()->quickUserCan( 'rollback', $user ) ) {
 681                                 // Get a rollback link without the brackets
 682                                 $rollbackLink = Linker::generateRollback(
 683                                         $rev,
 684                                         $this->getContext(),
 685                                         array( 'verify', 'noBrackets' )
 686                                 );
 687                                 if ( $rollbackLink ) {
 688                                         $this->preventClickjacking();
 689                                         $tools[] = $rollbackLink;
 690                                 }
 691                         }
 692
 693                         if ( !$rev->isDeleted( Revision::DELETED_TEXT )
 694                                 && !$prevRev->isDeleted( Revision::DELETED_TEXT )
 695                         ) {
 696                                 # Create undo tooltip for the first (=latest) line only
 697                                 $undoTooltip = $latest
 698                                         ? array( 'title' => $this->msg( 'tooltip-undo' )->text() )
 699                                         : array();
 700                                 $undolink = Linker::linkKnown(
 701                                         $this->getTitle(),
 702                                         $this->msg( 'editundo' )->escaped(),
 703                                         $undoTooltip,
 704                                         array(
 705                                                 'action' => 'edit',
 706                                                 'undoafter' => $prevRev->getId(),
 707                                                 'undo' => $rev->getId()
 708                                         )
 709                                 );
 710                                 $tools[] = "<span class=\"mw-history-undo\">{$undolink}</span>";
 711                         }
 712                 }
 713                 // Allow extension to add their own links here
 714                 wfRunHooks( 'HistoryRevisionTools', array( $rev, &$tools ) );
 715
 716                 if ( $tools ) {
 717                         $s2 .= ' ' . $this->msg( 'parentheses' )->rawParams( $lang->pipeList( $tools ) )->escaped();
 718                 }
 719
 720                 # Tags
 721                 list( $tagSummary, $newClasses ) = ChangeTags::formatSummaryRow( $row->ts_tags, 'history' );
 722                 $classes = array_merge( $classes, $newClasses );
 723                 if ( $tagSummary !== '' ) {
 724                         $s2 .= " $tagSummary";
 725                 }
 726
 727                 # Include separator between character difference and following text
 728                 if ( $s2 !== '' ) {
 729                         $s .= ' <span class="mw-changeslist-separator">. .</span> ' . $s2;
 730                 }
 731
 732                 wfRunHooks( 'PageHistoryLineEnding', array( $this, &$row, &$s, &$classes ) );
 733
 734                 $attribs = array();
 735                 if ( $classes ) {
 736                         $attribs['class'] = implode( ' ', $classes );
 737                 }
 738
 739                 return Xml::tags( 'li', $attribs, $s ) . "\n";
 740         }
 741
 742         /**
 743          * Create a link to view this revision of the page
 744          *
 745          * @param Revision $rev
 746          * @return string
 747          */
 748         function revLink( $rev ) {
 749                 $date = $this->getLanguage()->userTimeAndDate( $rev->getTimestamp(), $this->getUser() );
 750                 $date = htmlspecialchars( $date );
 751                 if ( $rev->userCan( Revision::DELETED_TEXT, $this->getUser() ) ) {
 752                         $link = Linker::linkKnown(
 753                                 $this->getTitle(),
 754                                 $date,
 755                                 array( 'class' => 'mw-changeslist-date' ),
 756                                 array( 'oldid' => $rev->getId() )
 757                         );
 758                 } else {
 759                         $link = $date;
 760                 }
 761                 if ( $rev->isDeleted( Revision::DELETED_TEXT ) ) {
 762                         $link = "<span class=\"history-deleted\">$link</span>";
 763                 }
 764
 765                 return $link;
 766         }
 767
 768         /**
 769          * Create a diff-to-current link for this revision for this page
 770          *
 771          * @param Revision $rev
 772          * @param bool $latest This is the latest revision of the page?
 773          * @return string
 774          */
 775         function curLink( $rev, $latest ) {
 776                 $cur = $this->historyPage->message['cur'];
 777                 if ( $latest || !$rev->userCan( Revision::DELETED_TEXT, $this->getUser() ) ) {
 778                         return $cur;
 779                 } else {
 780                         return Linker::linkKnown(
 781                                 $this->getTitle(),
 782                                 $cur,
 783                                 array(),
 784                                 array(
 785                                         'diff' => $this->getWikiPage()->getLatest(),
 786                                         'oldid' => $rev->getId()
 787                                 )
 788                         );
 789                 }
 790         }
 791
 792         /**
 793          * Create a diff-to-previous link for this revision for this page.
 794          *
 795          * @param Revision $prevRev The revision being displayed
 796          * @param stdClass|string|null $next The next revision in list (that is
 797          *        the previous one in chronological order).
 798          *        May either be a row, "unknown" or null.
 799          * @return string
 800          */
 801         function lastLink( $prevRev, $next ) {
 802                 $last = $this->historyPage->message['last'];
 803
 804                 if ( $next === null ) {
 805                         # Probably no next row
 806                         return $last;
 807                 }
 808
 809                 if ( $next === 'unknown' ) {
 810                         # Next row probably exists but is unknown, use an oldid=prev link
 811                         return Linker::linkKnown(
 812                                 $this->getTitle(),
 813                                 $last,
 814                                 array(),
 815                                 array(
 816                                         'diff' => $prevRev->getId(),
 817                                         'oldid' => 'prev'
 818                                 )
 819                         );
 820                 }
 821
 822                 $nextRev = new Revision( $next );
 823
 824                 if ( !$prevRev->userCan( Revision::DELETED_TEXT, $this->getUser() )
 825                         || !$nextRev->userCan( Revision::DELETED_TEXT, $this->getUser() )
 826                 ) {
 827                         return $last;
 828                 }
 829
 830                 return Linker::linkKnown(
 831                         $this->getTitle(),
 832                         $last,
 833                         array(),
 834                         array(
 835                                 'diff' => $prevRev->getId(),
 836                                 'oldid' => $next->rev_id
 837                         )
 838                 );
 839         }
 840
 841         /**
 842          * Create radio buttons for page history
 843          *
 844          * @param Revision $rev
 845          * @param bool $firstInList Is this version the first one?
 846          *
 847          * @return string HTML output for the radio buttons
 848          */
 849         function diffButtons( $rev, $firstInList ) {
 850                 if ( $this->getNumRows() > 1 ) {
 851                         $id = $rev->getId();
 852                         $radio = array( 'type' => 'radio', 'value' => $id );
 853                         /** @todo Move title texts to javascript */
 854                         if ( $firstInList ) {
 855                                 $first = Xml::element( 'input',
 856                                         array_merge( $radio, array(
 857                                                 'style' => 'visibility:hidden',
 858                                                 'name' => 'oldid',
 859                                                 'id' => 'mw-oldid-null' ) )
 860                                 );
 861                                 $checkmark = array( 'checked' => 'checked' );
 862                         } else {
 863                                 # Check visibility of old revisions
 864                                 if ( !$rev->userCan( Revision::DELETED_TEXT, $this->getUser() ) ) {
 865                                         $radio['disabled'] = 'disabled';
 866                                         $checkmark = array(); // We will check the next possible one
 867                                 } elseif ( !$this->oldIdChecked ) {
 868                                         $checkmark = array( 'checked' => 'checked' );
 869                                         $this->oldIdChecked = $id;
 870                                 } else {
 871                                         $checkmark = array();
 872                                 }
 873                                 $first = Xml::element( 'input',
 874                                         array_merge( $radio, $checkmark, array(
 875                                                 'name' => 'oldid',
 876                                                 'id' => "mw-oldid-$id" ) ) );
 877                                 $checkmark = array();
 878                         }
 879                         $second = Xml::element( 'input',
 880                                 array_merge( $radio, $checkmark, array(
 881                                         'name' => 'diff',
 882                                         'id' => "mw-diff-$id" ) ) );
 883
 884                         return $first . $second;
 885                 } else {
 886                         return '';
 887                 }
 888         }
 889
 890         /**
 891          * This is called if a write operation is possible from the generated HTML
 892          * @param bool $enable
 893          */
 894         function preventClickjacking( $enable = true ) {
 895                 $this->preventClickjacking = $enable;
 896         }
 897
 898         /**
 899          * Get the "prevent clickjacking" flag
 900          * @return bool
 901          */
 902         function getPreventClickjacking() {
 903                 return $this->preventClickjacking;
 904         }
 905 }