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 = HTMLFileCache::newFromTitle( $this->getTitle(), 'history' );
 114                         if ( !$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                 $out->addHTML(
 185                         "<form action=\"$action\" method=\"get\" id=\"mw-history-searchform\">" .
 186                         Xml::fieldset(
 187                                 $this->msg( 'history-fieldset-title' )->text(),
 188                                 false,
 189                                 array( 'id' => 'mw-history-search' )
 190                         ) .
 191                         Html::hidden( 'title', $this->getTitle()->getPrefixedDBkey() ) . "\n" .
 192                         Html::hidden( 'action', 'history' ) . "\n" .
 193                         Xml::dateMenu(
 194                                 ( $year == null ? MWTimestamp::getLocalInstance()->format( 'Y' ) : $year ),
 195                                 $month
 196                         ) . '&#160;' .
 197                         ( $tagSelector ? ( implode( '&#160;', $tagSelector ) . '&#160;' ) : '' ) .
 198                         $checkDeleted .
 199                         Xml::submitButton( $this->msg( 'allpagessubmit' )->text() ) . "\n" .
 200                         '</fieldset></form>'
 201                 );
 202
 203                 wfRunHooks( 'PageHistoryBeforeList', array( &$this->page, $this->getContext() ) );
 204
 205                 // Create and output the list.
 206                 $pager = new HistoryPager( $this, $year, $month, $tagFilter, $conds );
 207                 $out->addHTML(
 208                         $pager->getNavigationBar() .
 209                         $pager->getBody() .
 210                         $pager->getNavigationBar()
 211                 );
 212                 $out->preventClickjacking( $pager->getPreventClickjacking() );
 213
 214                 wfProfileOut( __METHOD__ );
 215         }
 216
 217         /**
 218          * Fetch an array of revisions, specified by a given limit, offset and
 219          * direction. This is now only used by the feeds. It was previously
 220          * used by the main UI but that's now handled by the pager.
 221          *
 222          * @param int $limit The limit number of revisions to get
 223          * @param int $offset
 224          * @param int $direction Either self::DIR_PREV or self::DIR_NEXT
 225          * @return ResultWrapper
 226          */
 227         function fetchRevisions( $limit, $offset, $direction ) {
 228                 // Fail if article doesn't exist.
 229                 if ( !$this->getTitle()->exists() ) {
 230                         return new FakeResultWrapper( array() );
 231                 }
 232
 233                 $dbr = wfGetDB( DB_SLAVE );
 234
 235                 if ( $direction === self::DIR_PREV ) {
 236                         list( $dirs, $oper ) = array( "ASC", ">=" );
 237                 } else { /* $direction === self::DIR_NEXT */
 238                         list( $dirs, $oper ) = array( "DESC", "<=" );
 239                 }
 240
 241                 if ( $offset ) {
 242                         $offsets = array( "rev_timestamp $oper " . $dbr->addQuotes( $dbr->timestamp( $offset ) ) );
 243                 } else {
 244                         $offsets = array();
 245                 }
 246
 247                 $page_id = $this->page->getId();
 248
 249                 return $dbr->select( 'revision',
 250                         Revision::selectFields(),
 251                         array_merge( array( 'rev_page' => $page_id ), $offsets ),
 252                         __METHOD__,
 253                         array( 'ORDER BY' => "rev_timestamp $dirs",
 254                                 'USE INDEX' => 'page_timestamp', 'LIMIT' => $limit )
 255                 );
 256         }
 257
 258         /**
 259          * Output a subscription feed listing recent edits to this page.
 260          *
 261          * @param string $type Feed type
 262          */
 263         function feed( $type ) {
 264                 if ( !FeedUtils::checkFeedOutput( $type ) ) {
 265                         return;
 266                 }
 267                 $request = $this->getRequest();
 268
 269                 $feedClasses = $this->context->getConfig()->get( 'FeedClasses' );
 270                 /** @var RSSFeed|AtomFeed $feed */
 271                 $feed = new $feedClasses[$type](
 272                         $this->getTitle()->getPrefixedText() . ' - ' .
 273                         $this->msg( 'history-feed-title' )->inContentLanguage()->text(),
 274                         $this->msg( 'history-feed-description' )->inContentLanguage()->text(),
 275                         $this->getTitle()->getFullURL( 'action=history' )
 276                 );
 277
 278                 // Get a limit on number of feed entries. Provide a sane default
 279                 // of 10 if none is defined (but limit to $wgFeedLimit max)
 280                 $limit = $request->getInt( 'limit', 10 );
 281                 $limit = min(
 282                         max( $limit, 1 ),
 283                         $this->context->getConfig()->get( 'FeedLimit' )
 284                 );
 285
 286                 $items = $this->fetchRevisions( $limit, 0, self::DIR_NEXT );
 287
 288                 // Generate feed elements enclosed between header and footer.
 289                 $feed->outHeader();
 290                 if ( $items->numRows() ) {
 291                         foreach ( $items as $row ) {
 292                                 $feed->outItem( $this->feedItem( $row ) );
 293                         }
 294                 } else {
 295                         $feed->outItem( $this->feedEmpty() );
 296                 }
 297                 $feed->outFooter();
 298         }
 299
 300         function feedEmpty() {
 301                 return new FeedItem(
 302                         $this->msg( 'nohistory' )->inContentLanguage()->text(),
 303                         $this->msg( 'history-feed-empty' )->inContentLanguage()->parseAsBlock(),
 304                         $this->getTitle()->getFullURL(),
 305                         wfTimestamp( TS_MW ),
 306                         '',
 307                         $this->getTitle()->getTalkPage()->getFullURL()
 308                 );
 309         }
 310
 311         /**
 312          * Generate a FeedItem object from a given revision table row
 313          * Borrows Recent Changes' feed generation functions for formatting;
 314          * includes a diff to the previous revision (if any).
 315          *
 316          * @param stdClass|array $row Database row
 317          * @return FeedItem
 318          */
 319         function feedItem( $row ) {
 320                 $rev = new Revision( $row );
 321                 $rev->setTitle( $this->getTitle() );
 322                 $text = FeedUtils::formatDiffRow(
 323                         $this->getTitle(),
 324                         $this->getTitle()->getPreviousRevisionID( $rev->getId() ),
 325                         $rev->getId(),
 326                         $rev->getTimestamp(),
 327                         $rev->getComment()
 328                 );
 329                 if ( $rev->getComment() == '' ) {
 330                         global $wgContLang;
 331                         $title = $this->msg( 'history-feed-item-nocomment',
 332                                 $rev->getUserText(),
 333                                 $wgContLang->timeanddate( $rev->getTimestamp() ),
 334                                 $wgContLang->date( $rev->getTimestamp() ),
 335                                 $wgContLang->time( $rev->getTimestamp() ) )->inContentLanguage()->text();
 336                 } else {
 337                         $title = $rev->getUserText() .
 338                                 $this->msg( 'colon-separator' )->inContentLanguage()->text() .
 339                                 FeedItem::stripComment( $rev->getComment() );
 340                 }
 341
 342                 return new FeedItem(
 343                         $title,
 344                         $text,
 345                         $this->getTitle()->getFullURL( 'diff=' . $rev->getId() . '&oldid=prev' ),
 346                         $rev->getTimestamp(),
 347                         $rev->getUserText(),
 348                         $this->getTitle()->getTalkPage()->getFullURL()
 349                 );
 350         }
 351 }
 352
 353 /**
 354  * @ingroup Pager
 355  * @ingroup Actions
 356  */
 357 class HistoryPager extends ReverseChronologicalPager {
 358         /**
 359          * @var bool|stdClass
 360          */
 361         public $lastRow = false;
 362
 363         public $counter, $historyPage, $buttons, $conds;
 364
 365         protected $oldIdChecked;
 366
 367         protected $preventClickjacking = false;
 368         /**
 369          * @var array
 370          */
 371         protected $parentLens;
 372
 373         /**
 374          * @param HistoryAction $historyPage
 375          * @param string $year
 376          * @param string $month
 377          * @param string $tagFilter
 378          * @param array $conds
 379          */
 380         function __construct( $historyPage, $year = '', $month = '', $tagFilter = '', $conds = array() ) {
 381                 parent::__construct( $historyPage->getContext() );
 382                 $this->historyPage = $historyPage;
 383                 $this->tagFilter = $tagFilter;
 384                 $this->getDateCond( $year, $month );
 385                 $this->conds = $conds;
 386         }
 387
 388         // For hook compatibility...
 389         function getArticle() {
 390                 return $this->historyPage->getArticle();
 391         }
 392
 393         function getSqlComment() {
 394                 if ( $this->conds ) {
 395                         return 'history page filtered'; // potentially slow, see CR r58153
 396                 } else {
 397                         return 'history page unfiltered';
 398                 }
 399         }
 400
 401         function getQueryInfo() {
 402                 $queryInfo = array(
 403                         'tables' => array( 'revision', 'user' ),
 404                         'fields' => array_merge( Revision::selectFields(), Revision::selectUserFields() ),
 405                         'conds' => array_merge(
 406                                 array( 'rev_page' => $this->getWikiPage()->getId() ),
 407                                 $this->conds ),
 408                         'options' => array( 'USE INDEX' => array( 'revision' => 'page_timestamp' ) ),
 409                         'join_conds' => array( 'user' => Revision::userJoinCond() ),
 410                 );
 411                 ChangeTags::modifyDisplayQuery(
 412                         $queryInfo['tables'],
 413                         $queryInfo['fields'],
 414                         $queryInfo['conds'],
 415                         $queryInfo['join_conds'],
 416                         $queryInfo['options'],
 417                         $this->tagFilter
 418                 );
 419                 wfRunHooks( 'PageHistoryPager::getQueryInfo', array( &$this, &$queryInfo ) );
 420
 421                 return $queryInfo;
 422         }
 423
 424         function getIndexField() {
 425                 return 'rev_timestamp';
 426         }
 427
 428         /**
 429          * @param stdClass $row
 430          * @return string
 431          */
 432         function formatRow( $row ) {
 433                 if ( $this->lastRow ) {
 434                         $latest = ( $this->counter == 1 && $this->mIsFirst );
 435                         $firstInList = $this->counter == 1;
 436                         $this->counter++;
 437                         $s = $this->historyLine( $this->lastRow, $row,
 438                                 $this->getTitle()->getNotificationTimestamp( $this->getUser() ), $latest, $firstInList );
 439                 } else {
 440                         $s = '';
 441                 }
 442                 $this->lastRow = $row;
 443
 444                 return $s;
 445         }
 446
 447         function doBatchLookups() {
 448                 # Do a link batch query
 449                 $this->mResult->seek( 0 );
 450                 $batch = new LinkBatch();
 451                 $revIds = array();
 452                 foreach ( $this->mResult as $row ) {
 453                         if ( $row->rev_parent_id ) {
 454                                 $revIds[] = $row->rev_parent_id;
 455                         }
 456                         if ( !is_null( $row->user_name ) ) {
 457                                 $batch->add( NS_USER, $row->user_name );
 458                                 $batch->add( NS_USER_TALK, $row->user_name );
 459                         } else { # for anons or usernames of imported revisions
 460                                 $batch->add( NS_USER, $row->rev_user_text );
 461                                 $batch->add( NS_USER_TALK, $row->rev_user_text );
 462                         }
 463                 }
 464                 $this->parentLens = Revision::getParentLengths( $this->mDb, $revIds );
 465                 $batch->execute();
 466                 $this->mResult->seek( 0 );
 467         }
 468
 469         /**
 470          * Creates begin of history list with a submit button
 471          *
 472          * @return string HTML output
 473          */
 474         function getStartBody() {
 475                 $this->lastRow = false;
 476                 $this->counter = 1;
 477                 $this->oldIdChecked = 0;
 478
 479                 $this->getOutput()->wrapWikiMsg( "<div class='mw-history-legend'>\n$1\n</div>", 'histlegend' );
 480                 $s = Html::openElement( 'form', array( 'action' => wfScript(),
 481                         'id' => 'mw-history-compare' ) ) . "\n";
 482                 $s .= Html::hidden( 'title', $this->getTitle()->getPrefixedDBkey() ) . "\n";
 483                 $s .= Html::hidden( 'action', 'historysubmit' ) . "\n";
 484
 485                 // Button container stored in $this->buttons for re-use in getEndBody()
 486                 $this->buttons = '<div>';
 487                 $className = 'historysubmit mw-history-compareselectedversions-button';
 488                 if ( $this->getConfig()->get( 'UseMediaWikiUIEverywhere' ) ) {
 489                         $className .= ' mw-ui-button mw-ui-constructive';
 490                 }
 491                 $this->buttons .= $this->submitButton( $this->msg( 'compareselectedversions' )->text(),
 492                         array( 'class' => $className )
 493                                 + Linker::tooltipAndAccesskeyAttribs( 'compareselectedversions' )
 494                 ) . "\n";
 495
 496                 if ( $this->getUser()->isAllowed( 'deleterevision' ) ) {
 497                         $this->buttons .= $this->getRevisionButton( 'revisiondelete', 'showhideselectedversions' );
 498                 }
 499                 $this->buttons .= '</div>';
 500
 501                 $s .= $this->buttons;
 502                 $s .= '<ul id="pagehistory">' . "\n";
 503
 504                 return $s;
 505         }
 506
 507         private function getRevisionButton( $name, $msg ) {
 508                 $this->preventClickjacking();
 509                 # Note bug #20966, <button> is non-standard in IE<8
 510                 $element = Html::element(
 511                         'button',
 512                         array(
 513                                 'type' => 'submit',
 514                                 'name' => $name,
 515                                 'value' => '1',
 516                                 'class' => "historysubmit mw-history-$name-button",
 517                         ),
 518                         $this->msg( $msg )->text()
 519                 ) . "\n";
 520                 return $element;
 521         }
 522
 523         function getEndBody() {
 524                 if ( $this->lastRow ) {
 525                         $latest = $this->counter == 1 && $this->mIsFirst;
 526                         $firstInList = $this->counter == 1;
 527                         if ( $this->mIsBackwards ) {
 528                                 # Next row is unknown, but for UI reasons, probably exists if an offset has been specified
 529                                 if ( $this->mOffset == '' ) {
 530                                         $next = null;
 531                                 } else {
 532                                         $next = 'unknown';
 533                                 }
 534                         } else {
 535                                 # The next row is the past-the-end row
 536                                 $next = $this->mPastTheEndRow;
 537                         }
 538                         $this->counter++;
 539                         $s = $this->historyLine( $this->lastRow, $next,
 540                                 $this->getTitle()->getNotificationTimestamp( $this->getUser() ), $latest, $firstInList );
 541                 } else {
 542                         $s = '';
 543                 }
 544                 $s .= "</ul>\n";
 545                 # Add second buttons only if there is more than one rev
 546                 if ( $this->getNumRows() > 2 ) {
 547                         $s .= $this->buttons;
 548                 }
 549                 $s .= '</form>';
 550
 551                 return $s;
 552         }
 553
 554         /**
 555          * Creates a submit button
 556          *
 557          * @param string $message Text of the submit button, will be escaped
 558          * @param array $attributes Attributes
 559          * @return string HTML output for the submit button
 560          */
 561         function submitButton( $message, $attributes = array() ) {
 562                 # Disable submit button if history has 1 revision only
 563                 if ( $this->getNumRows() > 1 ) {
 564                         return Xml::submitButton( $message, $attributes );
 565                 } else {
 566                         return '';
 567                 }
 568         }
 569
 570         /**
 571          * Returns a row from the history printout.
 572          *
 573          * @todo document some more, and maybe clean up the code (some params redundant?)
 574          *
 575          * @param stdClass $row The database row corresponding to the previous line.
 576          * @param mixed $next The database row corresponding to the next line
 577          *   (chronologically previous)
 578          * @param bool|string $notificationtimestamp
 579          * @param bool $latest Whether this row corresponds to the page's latest revision.
 580          * @param bool $firstInList Whether this row corresponds to the first
 581          *   displayed on this history page.
 582          * @return string HTML output for the row
 583          */
 584         function historyLine( $row, $next, $notificationtimestamp = false,
 585                 $latest = false, $firstInList = false ) {
 586                 $rev = new Revision( $row );
 587                 $rev->setTitle( $this->getTitle() );
 588
 589                 if ( is_object( $next ) ) {
 590                         $prevRev = new Revision( $next );
 591                         $prevRev->setTitle( $this->getTitle() );
 592                 } else {
 593                         $prevRev = null;
 594                 }
 595
 596                 $curlink = $this->curLink( $rev, $latest );
 597                 $lastlink = $this->lastLink( $rev, $next );
 598                 $curLastlinks = $curlink . $this->historyPage->message['pipe-separator'] . $lastlink;
 599                 $histLinks = Html::rawElement(
 600                         'span',
 601                         array( 'class' => 'mw-history-histlinks' ),
 602                         $this->msg( 'parentheses' )->rawParams( $curLastlinks )->escaped()
 603                 );
 604
 605                 $diffButtons = $this->diffButtons( $rev, $firstInList );
 606                 $s = $histLinks . $diffButtons;
 607
 608                 $link = $this->revLink( $rev );
 609                 $classes = array();
 610
 611                 $del = '';
 612                 $user = $this->getUser();
 613                 // Show checkboxes for each revision
 614                 if ( $user->isAllowed( 'deleterevision' ) ) {
 615                         $this->preventClickjacking();
 616                         // If revision was hidden from sysops, disable the checkbox
 617                         if ( !$rev->userCan( Revision::DELETED_RESTRICTED, $user ) ) {
 618                                 $del = Xml::check( 'deleterevisions', false, array( 'disabled' => 'disabled' ) );
 619                         // Otherwise, enable the checkbox...
 620                         } else {
 621                                 $del = Xml::check( 'showhiderevisions', false,
 622                                         array( 'name' => 'ids[' . $rev->getId() . ']' ) );
 623                         }
 624                 // User can only view deleted revisions...
 625                 } elseif ( $rev->getVisibility() && $user->isAllowed( 'deletedhistory' ) ) {
 626                         // If revision was hidden from sysops, disable the link
 627                         if ( !$rev->userCan( Revision::DELETED_RESTRICTED, $user ) ) {
 628                                 $del = Linker::revDeleteLinkDisabled( false );
 629                         // Otherwise, show the link...
 630                         } else {
 631                                 $query = array( 'type' => 'revision',
 632                                         'target' => $this->getTitle()->getPrefixedDBkey(), 'ids' => $rev->getId() );
 633                                 $del .= Linker::revDeleteLink( $query,
 634                                         $rev->isDeleted( Revision::DELETED_RESTRICTED ), false );
 635                         }
 636                 }
 637                 if ( $del ) {
 638                         $s .= " $del ";
 639                 }
 640
 641                 $lang = $this->getLanguage();
 642                 $dirmark = $lang->getDirMark();
 643
 644                 $s .= " $link";
 645                 $s .= $dirmark;
 646                 $s .= " <span class='history-user'>" .
 647                         Linker::revUserTools( $rev, true ) . "</span>";
 648                 $s .= $dirmark;
 649
 650                 if ( $rev->isMinor() ) {
 651                         $s .= ' ' . ChangesList::flag( 'minor' );
 652                 }
 653
 654                 # Sometimes rev_len isn't populated
 655                 if ( $rev->getSize() !== null ) {
 656                         # Size is always public data
 657                         $prevSize = isset( $this->parentLens[$row->rev_parent_id] )
 658                                 ? $this->parentLens[$row->rev_parent_id]
 659                                 : 0;
 660                         $sDiff = ChangesList::showCharacterDifference( $prevSize, $rev->getSize() );
 661                         $fSize = Linker::formatRevisionSize( $rev->getSize() );
 662                         $s .= ' <span class="mw-changeslist-separator">. .</span> ' . "$fSize $sDiff";
 663                 }
 664
 665                 # Text following the character difference is added just before running hooks
 666                 $s2 = Linker::revComment( $rev, false, true );
 667
 668                 if ( $notificationtimestamp && ( $row->rev_timestamp >= $notificationtimestamp ) ) {
 669                         $s2 .= ' <span class="updatedmarker">' . $this->msg( 'updatedmarker' )->escaped() . '</span>';
 670                         $classes[] = 'mw-history-line-updated';
 671                 }
 672
 673                 $tools = array();
 674
 675                 # Rollback and undo links
 676                 if ( $prevRev && $this->getTitle()->quickUserCan( 'edit', $user ) ) {
 677                         if ( $latest && $this->getTitle()->quickUserCan( 'rollback', $user ) ) {
 678                                 // Get a rollback link without the brackets
 679                                 $rollbackLink = Linker::generateRollback(
 680                                         $rev,
 681                                         $this->getContext(),
 682                                         array( 'verify', 'noBrackets' )
 683                                 );
 684                                 if ( $rollbackLink ) {
 685                                         $this->preventClickjacking();
 686                                         $tools[] = $rollbackLink;
 687                                 }
 688                         }
 689
 690                         if ( !$rev->isDeleted( Revision::DELETED_TEXT )
 691                                 && !$prevRev->isDeleted( Revision::DELETED_TEXT )
 692                         ) {
 693                                 # Create undo tooltip for the first (=latest) line only
 694                                 $undoTooltip = $latest
 695                                         ? array( 'title' => $this->msg( 'tooltip-undo' )->text() )
 696                                         : array();
 697                                 $undolink = Linker::linkKnown(
 698                                         $this->getTitle(),
 699                                         $this->msg( 'editundo' )->escaped(),
 700                                         $undoTooltip,
 701                                         array(
 702                                                 'action' => 'edit',
 703                                                 'undoafter' => $prevRev->getId(),
 704                                                 'undo' => $rev->getId()
 705                                         )
 706                                 );
 707                                 $tools[] = "<span class=\"mw-history-undo\">{$undolink}</span>";
 708                         }
 709                 }
 710                 // Allow extension to add their own links here
 711                 wfRunHooks( 'HistoryRevisionTools', array( $rev, &$tools ) );
 712
 713                 if ( $tools ) {
 714                         $s2 .= ' ' . $this->msg( 'parentheses' )->rawParams( $lang->pipeList( $tools ) )->escaped();
 715                 }
 716
 717                 # Tags
 718                 list( $tagSummary, $newClasses ) = ChangeTags::formatSummaryRow( $row->ts_tags, 'history' );
 719                 $classes = array_merge( $classes, $newClasses );
 720                 if ( $tagSummary !== '' ) {
 721                         $s2 .= " $tagSummary";
 722                 }
 723
 724                 # Include separator between character difference and following text
 725                 if ( $s2 !== '' ) {
 726                         $s .= ' <span class="mw-changeslist-separator">. .</span> ' . $s2;
 727                 }
 728
 729                 wfRunHooks( 'PageHistoryLineEnding', array( $this, &$row, &$s, &$classes ) );
 730
 731                 $attribs = array();
 732                 if ( $classes ) {
 733                         $attribs['class'] = implode( ' ', $classes );
 734                 }
 735
 736                 return Xml::tags( 'li', $attribs, $s ) . "\n";
 737         }
 738
 739         /**
 740          * Create a link to view this revision of the page
 741          *
 742          * @param Revision $rev
 743          * @return string
 744          */
 745         function revLink( $rev ) {
 746                 $date = $this->getLanguage()->userTimeAndDate( $rev->getTimestamp(), $this->getUser() );
 747                 $date = htmlspecialchars( $date );
 748                 if ( $rev->userCan( Revision::DELETED_TEXT, $this->getUser() ) ) {
 749                         $link = Linker::linkKnown(
 750                                 $this->getTitle(),
 751                                 $date,
 752                                 array( 'class' => 'mw-changeslist-date' ),
 753                                 array( 'oldid' => $rev->getId() )
 754                         );
 755                 } else {
 756                         $link = $date;
 757                 }
 758                 if ( $rev->isDeleted( Revision::DELETED_TEXT ) ) {
 759                         $link = "<span class=\"history-deleted\">$link</span>";
 760                 }
 761
 762                 return $link;
 763         }
 764
 765         /**
 766          * Create a diff-to-current link for this revision for this page
 767          *
 768          * @param Revision $rev
 769          * @param bool $latest This is the latest revision of the page?
 770          * @return string
 771          */
 772         function curLink( $rev, $latest ) {
 773                 $cur = $this->historyPage->message['cur'];
 774                 if ( $latest || !$rev->userCan( Revision::DELETED_TEXT, $this->getUser() ) ) {
 775                         return $cur;
 776                 } else {
 777                         return Linker::linkKnown(
 778                                 $this->getTitle(),
 779                                 $cur,
 780                                 array(),
 781                                 array(
 782                                         'diff' => $this->getWikiPage()->getLatest(),
 783                                         'oldid' => $rev->getId()
 784                                 )
 785                         );
 786                 }
 787         }
 788
 789         /**
 790          * Create a diff-to-previous link for this revision for this page.
 791          *
 792          * @param Revision $prevRev The revision being displayed
 793          * @param stdClass|string|null $next The next revision in list (that is
 794          *        the previous one in chronological order).
 795          *        May either be a row, "unknown" or null.
 796          * @return string
 797          */
 798         function lastLink( $prevRev, $next ) {
 799                 $last = $this->historyPage->message['last'];
 800
 801                 if ( $next === null ) {
 802                         # Probably no next row
 803                         return $last;
 804                 }
 805
 806                 if ( $next === 'unknown' ) {
 807                         # Next row probably exists but is unknown, use an oldid=prev link
 808                         return Linker::linkKnown(
 809                                 $this->getTitle(),
 810                                 $last,
 811                                 array(),
 812                                 array(
 813                                         'diff' => $prevRev->getId(),
 814                                         'oldid' => 'prev'
 815                                 )
 816                         );
 817                 }
 818
 819                 $nextRev = new Revision( $next );
 820
 821                 if ( !$prevRev->userCan( Revision::DELETED_TEXT, $this->getUser() )
 822                         || !$nextRev->userCan( Revision::DELETED_TEXT, $this->getUser() )
 823                 ) {
 824                         return $last;
 825                 }
 826
 827                 return Linker::linkKnown(
 828                         $this->getTitle(),
 829                         $last,
 830                         array(),
 831                         array(
 832                                 'diff' => $prevRev->getId(),
 833                                 'oldid' => $next->rev_id
 834                         )
 835                 );
 836         }
 837
 838         /**
 839          * Create radio buttons for page history
 840          *
 841          * @param Revision $rev
 842          * @param bool $firstInList Is this version the first one?
 843          *
 844          * @return string HTML output for the radio buttons
 845          */
 846         function diffButtons( $rev, $firstInList ) {
 847                 if ( $this->getNumRows() > 1 ) {
 848                         $id = $rev->getId();
 849                         $radio = array( 'type' => 'radio', 'value' => $id );
 850                         /** @todo Move title texts to javascript */
 851                         if ( $firstInList ) {
 852                                 $first = Xml::element( 'input',
 853                                         array_merge( $radio, array(
 854                                                 'style' => 'visibility:hidden',
 855                                                 'name' => 'oldid',
 856                                                 'id' => 'mw-oldid-null' ) )
 857                                 );
 858                                 $checkmark = array( 'checked' => 'checked' );
 859                         } else {
 860                                 # Check visibility of old revisions
 861                                 if ( !$rev->userCan( Revision::DELETED_TEXT, $this->getUser() ) ) {
 862                                         $radio['disabled'] = 'disabled';
 863                                         $checkmark = array(); // We will check the next possible one
 864                                 } elseif ( !$this->oldIdChecked ) {
 865                                         $checkmark = array( 'checked' => 'checked' );
 866                                         $this->oldIdChecked = $id;
 867                                 } else {
 868                                         $checkmark = array();
 869                                 }
 870                                 $first = Xml::element( 'input',
 871                                         array_merge( $radio, $checkmark, array(
 872                                                 'name' => 'oldid',
 873                                                 'id' => "mw-oldid-$id" ) ) );
 874                                 $checkmark = array();
 875                         }
 876                         $second = Xml::element( 'input',
 877                                 array_merge( $radio, $checkmark, array(
 878                                         'name' => 'diff',
 879                                         'id' => "mw-diff-$id" ) ) );
 880
 881                         return $first . $second;
 882                 } else {
 883                         return '';
 884                 }
 885         }
 886
 887         /**
 888          * This is called if a write operation is possible from the generated HTML
 889          * @param bool $enable
 890          */
 891         function preventClickjacking( $enable = true ) {
 892                 $this->preventClickjacking = $enable;
 893         }
 894
 895         /**
 896          * Get the "prevent clickjacking" flag
 897          * @return bool
 898          */
 899         function getPreventClickjacking() {
 900                 return $this->preventClickjacking;
 901         }
 902 }