includes/HistoryPage.php

   1 <?php
   2 /**
   3  * Page history
   4  *
   5  * Split off from Article.php and Skin.php, 2003-12-22
   6  * @file
   7  */
   8
   9 /**
  10  * This class handles printing the history page for an article.  In order to
  11  * be efficient, it uses timestamps rather than offsets for paging, to avoid
  12  * costly LIMIT,offset queries.
  13  *
  14  * Construct it by passing in an Article, and call $h->history() to print the
  15  * history.
  16  *
  17  */
  18 class HistoryPage extends ContextSource {
  19         const DIR_PREV = 0;
  20         const DIR_NEXT = 1;
  21
  22         /** Contains the Page object. Passed on construction. */
  23         protected $article;
  24
  25         /**
  26          * Construct a new HistoryPage.
  27          *
  28          * @param $article Article
  29          */
  30         function __construct( Page $page, IContextSource $context ) {
  31                 $this->article = $page;
  32                 $this->context = clone $context; // don't clobber the main context
  33                 $this->context->setTitle( $page->getTitle() ); // must match
  34                 $this->preCacheMessages();
  35         }
  36
  37         /**
  38          * Get the Article object we are working on.
  39          * @return Page
  40          */
  41         public function getArticle() {
  42                 return $this->article;
  43         }
  44
  45         /**
  46          * As we use the same small set of messages in various methods and that
  47          * they are called often, we call them once and save them in $this->message
  48          */
  49         private function preCacheMessages() {
  50                 // Precache various messages
  51                 if ( !isset( $this->message ) ) {
  52                         $msgs = array( 'cur', 'last', 'pipe-separator' );
  53                         foreach ( $msgs as $msg ) {
  54                                 $this->message[$msg] = wfMsgExt( $msg, array( 'escapenoentities' ) );
  55                         }
  56                 }
  57         }
  58
  59         /**
  60          * Print the history page for an article.
  61          * @return nothing
  62          */
  63         function history() {
  64                 global $wgScript, $wgUseFileCache;
  65                 $out = $this->getOutput();
  66                 $request = $this->getRequest();
  67
  68                 /**
  69                  * Allow client caching.
  70                  */
  71                 if ( $out->checkLastModified( $this->article->getTouched() ) ) {
  72                         return; // Client cache fresh and headers sent, nothing more to do.
  73                 }
  74
  75                 wfProfileIn( __METHOD__ );
  76
  77                 # Fill in the file cache if not set already
  78                 if ( $wgUseFileCache && HTMLFileCache::useFileCache( $this->getContext() ) ) {
  79                         $cache = HTMLFileCache::newFromTitle( $this->getTitle(), 'history' );
  80                         if ( !$cache->isCacheGood( /* Assume up to date */ ) ) {
  81                                 ob_start( array( &$cache, 'saveToFileCache' ) );
  82                         }
  83                 }
  84
  85                 // Setup page variables.
  86                 $out->setPageTitle( wfMsg( 'history-title', $this->getTitle()->getPrefixedText() ) );
  87                 $out->setPageTitleActionText( wfMsg( 'history_short' ) );
  88                 $out->setArticleFlag( false );
  89                 $out->setArticleRelated( true );
  90                 $out->setRobotPolicy( 'noindex,nofollow' );
  91                 $out->setFeedAppendQuery( 'action=history' );
  92                 $out->addModules( array( 'mediawiki.legacy.history', 'mediawiki.action.history' ) );
  93
  94                 // Creation of a subtitle link pointing to [[Special:Log]]
  95                 $logPage = SpecialPage::getTitleFor( 'Log' );
  96                 $logLink = Linker::linkKnown(
  97                         $logPage,
  98                         wfMsgHtml( 'viewpagelogs' ),
  99                         array(),
 100                         array( 'page' => $this->getTitle()->getPrefixedText() )
 101                 );
 102                 $out->setSubtitle( $logLink );
 103
 104                 // Handle atom/RSS feeds.
 105                 $feedType = $request->getVal( 'feed' );
 106                 if ( $feedType ) {
 107                         wfProfileOut( __METHOD__ );
 108                         return $this->feed( $feedType );
 109                 }
 110
 111                 // Fail nicely if article doesn't exist.
 112                 if ( !$this->getTitle()->exists() ) {
 113                         $out->addWikiMsg( 'nohistory' );
 114                         # show deletion/move log if there is an entry
 115                         LogEventsList::showLogExtract(
 116                                 $out,
 117                                 array( 'delete', 'move' ),
 118                                 $this->getTitle(),
 119                                 '',
 120                                 array(  'lim' => 10,
 121                                         'conds' => array( "log_action != 'revision'" ),
 122                                         'showIfEmpty' => false,
 123                                         'msgKey' => array( 'moveddeleted-notice' )
 124                                 )
 125                         );
 126                         wfProfileOut( __METHOD__ );
 127                         return;
 128                 }
 129
 130                 /**
 131                  * Add date selector to quickly get to a certain time
 132                  */
 133                 $year        = $request->getInt( 'year' );
 134                 $month       = $request->getInt( 'month' );
 135                 $tagFilter   = $request->getVal( 'tagfilter' );
 136                 $tagSelector = ChangeTags::buildTagFilterSelector( $tagFilter );
 137
 138                 /**
 139                  * Option to show only revisions that have been (partially) hidden via RevisionDelete
 140                  */
 141                 if ( $request->getBool( 'deleted' ) ) {
 142                         $conds = array( "rev_deleted != '0'" );
 143                 } else {
 144                         $conds = array();
 145                 }
 146                 $checkDeleted = Xml::checkLabel( wfMsg( 'history-show-deleted' ),
 147                         'deleted', 'mw-show-deleted-only', $request->getBool( 'deleted' ) ) . "\n";
 148
 149                 // Add the general form
 150                 $action = htmlspecialchars( $wgScript );
 151                 $out->addHTML(
 152                         "<form action=\"$action\" method=\"get\" id=\"mw-history-searchform\">" .
 153                         Xml::fieldset(
 154                                 wfMsg( 'history-fieldset-title' ),
 155                                 false,
 156                                 array( 'id' => 'mw-history-search' )
 157                         ) .
 158                         Html::hidden( 'title', $this->getTitle()->getPrefixedDBKey() ) . "\n" .
 159                         Html::hidden( 'action', 'history' ) . "\n" .
 160                         Xml::dateMenu( $year, $month ) . '&#160;' .
 161                         ( $tagSelector ? ( implode( '&#160;', $tagSelector ) . '&#160;' ) : '' ) .
 162                         $checkDeleted .
 163                         Xml::submitButton( wfMsg( 'allpagessubmit' ) ) . "\n" .
 164                         '</fieldset></form>'
 165                 );
 166
 167                 wfRunHooks( 'PageHistoryBeforeList', array( &$this->article ) );
 168
 169                 // Create and output the list.
 170                 $pager = new HistoryPager( $this, $year, $month, $tagFilter, $conds );
 171                 $out->addHTML(
 172                         $pager->getNavigationBar() .
 173                         $pager->getBody() .
 174                         $pager->getNavigationBar()
 175                 );
 176                 $out->preventClickjacking( $pager->getPreventClickjacking() );
 177
 178                 wfProfileOut( __METHOD__ );
 179         }
 180
 181         /**
 182          * Fetch an array of revisions, specified by a given limit, offset and
 183          * direction. This is now only used by the feeds. It was previously
 184          * used by the main UI but that's now handled by the pager.
 185          *
 186          * @param $limit Integer: the limit number of revisions to get
 187          * @param $offset Integer
 188          * @param $direction Integer: either HistoryPage::DIR_PREV or HistoryPage::DIR_NEXT
 189          * @return ResultWrapper
 190          */
 191         function fetchRevisions( $limit, $offset, $direction ) {
 192                 $dbr = wfGetDB( DB_SLAVE );
 193
 194                 if ( $direction == HistoryPage::DIR_PREV ) {
 195                         list( $dirs, $oper ) = array( "ASC", ">=" );
 196                 } else { /* $direction == HistoryPage::DIR_NEXT */
 197                         list( $dirs, $oper ) = array( "DESC", "<=" );
 198                 }
 199
 200                 if ( $offset ) {
 201                         $offsets = array( "rev_timestamp $oper '$offset'" );
 202                 } else {
 203                         $offsets = array();
 204                 }
 205
 206                 $page_id = $this->getTitle()->getArticleID();
 207
 208                 return $dbr->select( 'revision',
 209                         Revision::selectFields(),
 210                         array_merge( array( "rev_page=$page_id" ), $offsets ),
 211                         __METHOD__,
 212                         array( 'ORDER BY' => "rev_timestamp $dirs",
 213                                 'USE INDEX' => 'page_timestamp', 'LIMIT' => $limit )
 214                 );
 215         }
 216
 217         /**
 218          * Output a subscription feed listing recent edits to this page.
 219          *
 220          * @param $type String: feed type
 221          */
 222         function feed( $type ) {
 223                 global $wgFeedClasses, $wgFeedLimit;
 224                 if ( !FeedUtils::checkFeedOutput( $type ) ) {
 225                         return;
 226                 }
 227                 $request = $this->getRequest();
 228
 229                 $feed = new $wgFeedClasses[$type](
 230                         $this->getTitle()->getPrefixedText() . ' - ' .
 231                         wfMsgForContent( 'history-feed-title' ),
 232                         wfMsgForContent( 'history-feed-description' ),
 233                         $this->getTitle()->getFullUrl( 'action=history' )
 234                 );
 235
 236                 // Get a limit on number of feed entries. Provide a sane default
 237                 // of 10 if none is defined (but limit to $wgFeedLimit max)
 238                 $limit = $request->getInt( 'limit', 10 );
 239                 if ( $limit > $wgFeedLimit || $limit < 1 ) {
 240                         $limit = 10;
 241                 }
 242                 $items = $this->fetchRevisions( $limit, 0, HistoryPage::DIR_NEXT );
 243
 244                 // Generate feed elements enclosed between header and footer.
 245                 $feed->outHeader();
 246                 if ( $items ) {
 247                         foreach ( $items as $row ) {
 248                                 $feed->outItem( $this->feedItem( $row ) );
 249                         }
 250                 } else {
 251                         $feed->outItem( $this->feedEmpty() );
 252                 }
 253                 $feed->outFooter();
 254         }
 255
 256         function feedEmpty() {
 257                 return new FeedItem(
 258                         wfMsgForContent( 'nohistory' ),
 259                         $this->getOutput()->parse( wfMsgForContent( 'history-feed-empty' ) ),
 260                         $this->getTitle()->getFullUrl(),
 261                         wfTimestamp( TS_MW ),
 262                         '',
 263                         $this->getTitle()->getTalkPage()->getFullUrl()
 264                 );
 265         }
 266
 267         /**
 268          * Generate a FeedItem object from a given revision table row
 269          * Borrows Recent Changes' feed generation functions for formatting;
 270          * includes a diff to the previous revision (if any).
 271          *
 272          * @param $row Object: database row
 273          * @return FeedItem
 274          */
 275         function feedItem( $row ) {
 276                 $rev = new Revision( $row );
 277                 $rev->setTitle( $this->getTitle() );
 278                 $text = FeedUtils::formatDiffRow(
 279                         $this->getTitle(),
 280                         $this->getTitle()->getPreviousRevisionID( $rev->getId() ),
 281                         $rev->getId(),
 282                         $rev->getTimestamp(),
 283                         $rev->getComment()
 284                 );
 285                 if ( $rev->getComment() == '' ) {
 286                         global $wgContLang;
 287                         $title = wfMsgForContent( 'history-feed-item-nocomment',
 288                                 $rev->getUserText(),
 289                                 $wgContLang->timeanddate( $rev->getTimestamp() ),
 290                                 $wgContLang->date( $rev->getTimestamp() ),
 291                                 $wgContLang->time( $rev->getTimestamp() )
 292                         );
 293                 } else {
 294                         $title = $rev->getUserText() .
 295                         wfMsgForContent( 'colon-separator' ) .
 296                         FeedItem::stripComment( $rev->getComment() );
 297                 }
 298                 return new FeedItem(
 299                         $title,
 300                         $text,
 301                         $this->getTitle()->getFullUrl( 'diff=' . $rev->getId() . '&oldid=prev' ),
 302                         $rev->getTimestamp(),
 303                         $rev->getUserText(),
 304                         $this->getTitle()->getTalkPage()->getFullUrl()
 305                 );
 306         }
 307 }
 308
 309 /**
 310  * @ingroup Pager
 311  */
 312 class HistoryPager extends ReverseChronologicalPager {
 313         public $lastRow = false, $counter, $historyPage, $title, $buttons, $conds;
 314         protected $oldIdChecked;
 315         protected $preventClickjacking = false;
 316
 317         function __construct( $historyPage, $year = '', $month = '', $tagFilter = '', $conds = array() ) {
 318                 parent::__construct();
 319                 $this->historyPage = $historyPage;
 320                 $this->title = $this->historyPage->getTitle();
 321                 $this->tagFilter = $tagFilter;
 322                 $this->getDateCond( $year, $month );
 323                 $this->conds = $conds;
 324         }
 325
 326         // For hook compatibility...
 327         function getArticle() {
 328                 return $this->historyPage->getArticle();
 329         }
 330
 331         function getTitle() {
 332                 return $this->title;
 333         }
 334
 335         function getSqlComment() {
 336                 if ( $this->conds ) {
 337                         return 'history page filtered'; // potentially slow, see CR r58153
 338                 } else {
 339                         return 'history page unfiltered';
 340                 }
 341         }
 342
 343         function getQueryInfo() {
 344                 $queryInfo = array(
 345                         'tables'  => array( 'revision', 'user' ),
 346                         'fields'  => array_merge( Revision::selectFields(), Revision::selectUserFields() ),
 347                         'conds'   => array_merge(
 348                                 array( 'rev_page' => $this->title->getArticleID() ),
 349                                 $this->conds ),
 350                         'options' => array( 'USE INDEX' => array( 'revision' => 'page_timestamp' ) ),
 351                         'join_conds' => array(
 352                                 'user'        => array( 'LEFT JOIN', 'rev_user != 0 AND user_id = rev_user' ),
 353                                 'tag_summary' => array( 'LEFT JOIN', 'ts_rev_id=rev_id' ) ),
 354                 );
 355                 ChangeTags::modifyDisplayQuery(
 356                         $queryInfo['tables'],
 357                         $queryInfo['fields'],
 358                         $queryInfo['conds'],
 359                         $queryInfo['join_conds'],
 360                         $queryInfo['options'],
 361                         $this->tagFilter
 362                 );
 363                 wfRunHooks( 'PageHistoryPager::getQueryInfo', array( &$this, &$queryInfo ) );
 364                 return $queryInfo;
 365         }
 366
 367         function getIndexField() {
 368                 return 'rev_timestamp';
 369         }
 370
 371         function formatRow( $row ) {
 372                 if ( $this->lastRow ) {
 373                         $latest = ( $this->counter == 1 && $this->mIsFirst );
 374                         $firstInList = $this->counter == 1;
 375                         $this->counter++;
 376                         $s = $this->historyLine( $this->lastRow, $row,
 377                                 $this->title->getNotificationTimestamp(), $latest, $firstInList );
 378                 } else {
 379                         $s = '';
 380                 }
 381                 $this->lastRow = $row;
 382                 return $s;
 383         }
 384
 385         function doBatchLookups() {
 386                 # Do a link batch query
 387                 $this->mResult->seek( 0 );
 388                 $batch = new LinkBatch();
 389                 # Give some pointers to make (last) links
 390                 foreach ( $this->mResult as $row ) {
 391                         $batch->addObj( Title::makeTitleSafe( NS_USER, $row->user_name ) );
 392                         $batch->addObj( Title::makeTitleSafe( NS_USER_TALK, $row->user_name ) );
 393                 }
 394                 $batch->execute();
 395                 $this->mResult->seek( 0 );
 396         }
 397
 398         /**
 399          * Creates begin of history list with a submit button
 400          *
 401          * @return string HTML output
 402          */
 403         function getStartBody() {
 404                 global $wgScript, $wgUser, $wgOut;
 405                 $this->lastRow = false;
 406                 $this->counter = 1;
 407                 $this->oldIdChecked = 0;
 408
 409                 $wgOut->wrapWikiMsg( "<div class='mw-history-legend'>\n$1\n</div>", 'histlegend' );
 410                 $s = Html::openElement( 'form', array( 'action' => $wgScript,
 411                         'id' => 'mw-history-compare' ) ) . "\n";
 412                 $s .= Html::hidden( 'title', $this->title->getPrefixedDbKey() ) . "\n";
 413                 $s .= Html::hidden( 'action', 'historysubmit' ) . "\n";
 414
 415                 $s .= '<div>' . $this->submitButton( wfMsg( 'compareselectedversions' ),
 416                         array( 'class' => 'historysubmit' ) ) . "\n";
 417
 418                 $this->buttons = '<div>';
 419                 $this->buttons .= $this->submitButton( wfMsg( 'compareselectedversions' ),
 420                         array( 'class' => 'historysubmit' )
 421                                 + Linker::tooltipAndAccesskeyAttribs( 'compareselectedversions' )
 422                 ) . "\n";
 423
 424                 if ( $wgUser->isAllowed( 'deleterevision' ) ) {
 425                         $s .= $this->getRevisionButton( 'revisiondelete', 'showhideselectedversions' );
 426                 }
 427                 $this->buttons .= '</div>';
 428                 $s .= '</div><ul id="pagehistory">' . "\n";
 429                 return $s;
 430         }
 431
 432         private function getRevisionButton( $name, $msg ) {
 433                 $this->preventClickjacking();
 434                 # Note bug #20966, <button> is non-standard in IE<8
 435                 $element = Html::element( 'button',
 436                         array(
 437                                 'type' => 'submit',
 438                                 'name' => $name,
 439                                 'value' => '1',
 440                                 'class' => "mw-history-$name-button",
 441                         ),
 442                         wfMsg( $msg )
 443                 ) . "\n";
 444                 $this->buttons .= $element;
 445                 return $element;
 446         }
 447
 448         function getEndBody() {
 449                 if ( $this->lastRow ) {
 450                         $latest = $this->counter == 1 && $this->mIsFirst;
 451                         $firstInList = $this->counter == 1;
 452                         if ( $this->mIsBackwards ) {
 453                                 # Next row is unknown, but for UI reasons, probably exists if an offset has been specified
 454                                 if ( $this->mOffset == '' ) {
 455                                         $next = null;
 456                                 } else {
 457                                         $next = 'unknown';
 458                                 }
 459                         } else {
 460                                 # The next row is the past-the-end row
 461                                 $next = $this->mPastTheEndRow;
 462                         }
 463                         $this->counter++;
 464                         $s = $this->historyLine( $this->lastRow, $next,
 465                                 $this->title->getNotificationTimestamp(), $latest, $firstInList );
 466                 } else {
 467                         $s = '';
 468                 }
 469                 $s .= "</ul>\n";
 470                 # Add second buttons only if there is more than one rev
 471                 if ( $this->getNumRows() > 2 ) {
 472                         $s .= $this->buttons;
 473                 }
 474                 $s .= '</form>';
 475                 return $s;
 476         }
 477
 478         /**
 479          * Creates a submit button
 480          *
 481          * @param $message String: text of the submit button, will be escaped
 482          * @param $attributes Array: attributes
 483          * @return String: HTML output for the submit button
 484          */
 485         function submitButton( $message, $attributes = array() ) {
 486                 # Disable submit button if history has 1 revision only
 487                 if ( $this->getNumRows() > 1 ) {
 488                         return Xml::submitButton( $message , $attributes );
 489                 } else {
 490                         return '';
 491                 }
 492         }
 493
 494         /**
 495          * Returns a row from the history printout.
 496          *
 497          * @todo document some more, and maybe clean up the code (some params redundant?)
 498          *
 499          * @param $row Object: the database row corresponding to the previous line.
 500          * @param $next Mixed: the database row corresponding to the next line.
 501          * @param $notificationtimestamp
 502          * @param $latest Boolean: whether this row corresponds to the page's latest revision.
 503          * @param $firstInList Boolean: whether this row corresponds to the first displayed on this history page.
 504          * @return String: HTML output for the row
 505          */
 506         function historyLine( $row, $next, $notificationtimestamp = false,
 507                 $latest = false, $firstInList = false )
 508         {
 509                 global $wgUser, $wgLang;
 510                 $rev = new Revision( $row );
 511                 $rev->setTitle( $this->title );
 512
 513                 $curlink = $this->curLink( $rev, $latest );
 514                 $lastlink = $this->lastLink( $rev, $next );
 515                 $diffButtons = $this->diffButtons( $rev, $firstInList );
 516                 $histLinks = Html::rawElement(
 517                                 'span',
 518                                 array( 'class' => 'mw-history-histlinks' ),
 519                                 '(' . $curlink . $this->historyPage->message['pipe-separator'] . $lastlink . ') '
 520                 );
 521                 $s = $histLinks . $diffButtons;
 522
 523                 $link = $this->revLink( $rev );
 524                 $classes = array();
 525
 526                 $del = '';
 527                 // Show checkboxes for each revision
 528                 if ( $wgUser->isAllowed( 'deleterevision' ) ) {
 529                         $this->preventClickjacking();
 530                         // If revision was hidden from sysops, disable the checkbox
 531                         if ( !$rev->userCan( Revision::DELETED_RESTRICTED ) ) {
 532                                 $del = Xml::check( 'deleterevisions', false, array( 'disabled' => 'disabled' ) );
 533                         // Otherwise, enable the checkbox...
 534                         } else {
 535                                 $del = Xml::check( 'showhiderevisions', false,
 536                                         array( 'name' => 'ids[' . $rev->getId() . ']' ) );
 537                         }
 538                 // User can only view deleted revisions...
 539                 } elseif ( $rev->getVisibility() && $wgUser->isAllowed( 'deletedhistory' ) ) {
 540                         // If revision was hidden from sysops, disable the link
 541                         if ( !$rev->userCan( Revision::DELETED_RESTRICTED ) ) {
 542                                 $cdel = Linker::revDeleteLinkDisabled( false );
 543                         // Otherwise, show the link...
 544                         } else {
 545                                 $query = array( 'type' => 'revision',
 546                                         'target' => $this->title->getPrefixedDbkey(), 'ids' => $rev->getId() );
 547                                 $del .= Linker::revDeleteLink( $query,
 548                                         $rev->isDeleted( Revision::DELETED_RESTRICTED ), false );
 549                         }
 550                 }
 551                 if ( $del ) {
 552                         $s .= " $del ";
 553                 }
 554
 555                 $dirmark = $wgLang->getDirMark();
 556
 557                 $s .= " $link";
 558                 $s .= $dirmark;
 559                 $s .= " <span class='history-user'>" .
 560                         Linker::revUserTools( $rev, true ) . "</span>";
 561                 $s .= $dirmark;
 562
 563                 if ( $rev->isMinor() ) {
 564                         $s .= ' ' . ChangesList::flag( 'minor' );
 565                 }
 566
 567                 if ( !is_null( $size = $rev->getSize() ) && !$rev->isDeleted( Revision::DELETED_TEXT ) ) {
 568                         $s .= ' ' . Linker::formatRevisionSize( $size );
 569                 }
 570
 571                 $s .= Linker::revComment( $rev, false, true );
 572
 573                 if ( $notificationtimestamp && ( $row->rev_timestamp >= $notificationtimestamp ) ) {
 574                         $s .= ' <span class="updatedmarker">' .  wfMsgHtml( 'updatedmarker' ) . '</span>';
 575                 }
 576
 577                 $tools = array();
 578
 579                 # Rollback and undo links
 580                 if ( !is_null( $next ) && is_object( $next ) ) {
 581                         if ( $latest && $this->title->userCan( 'rollback' ) && $this->title->userCan( 'edit' ) ) {
 582                                 $this->preventClickjacking();
 583                                 $tools[] = '<span class="mw-rollback-link">' .
 584                                         Linker::buildRollbackLink( $rev ) . '</span>';
 585                         }
 586
 587                         if ( $this->title->quickUserCan( 'edit' )
 588                                 && !$rev->isDeleted( Revision::DELETED_TEXT )
 589                                 && !$next->rev_deleted & Revision::DELETED_TEXT )
 590                         {
 591                                 # Create undo tooltip for the first (=latest) line only
 592                                 $undoTooltip = $latest
 593                                         ? array( 'title' => wfMsg( 'tooltip-undo' ) )
 594                                         : array();
 595                                 $undolink = Linker::linkKnown(
 596                                         $this->title,
 597                                         wfMsgHtml( 'editundo' ),
 598                                         $undoTooltip,
 599                                         array(
 600                                                 'action' => 'edit',
 601                                                 'undoafter' => $next->rev_id,
 602                                                 'undo' => $rev->getId()
 603                                         )
 604                                 );
 605                                 $tools[] = "<span class=\"mw-history-undo\">{$undolink}</span>";
 606                         }
 607                 }
 608
 609                 if ( $tools ) {
 610                         $s .= ' (' . $wgLang->pipeList( $tools ) . ')';
 611                 }
 612
 613                 # Tags
 614                 list( $tagSummary, $newClasses ) = ChangeTags::formatSummaryRow( $row->ts_tags, 'history' );
 615                 $classes = array_merge( $classes, $newClasses );
 616                 $s .= " $tagSummary";
 617
 618                 wfRunHooks( 'PageHistoryLineEnding', array( $this, &$row , &$s, &$classes ) );
 619
 620                 $attribs = array();
 621                 if ( $classes ) {
 622                         $attribs['class'] = implode( ' ', $classes );
 623                 }
 624
 625                 return Xml::tags( 'li', $attribs, $s ) . "\n";
 626         }
 627
 628         /**
 629          * Create a link to view this revision of the page
 630          *
 631          * @param $rev Revision
 632          * @return String
 633          */
 634         function revLink( $rev ) {
 635                 global $wgLang;
 636                 $date = $wgLang->timeanddate( wfTimestamp( TS_MW, $rev->getTimestamp() ), true );
 637                 $date = htmlspecialchars( $date );
 638                 if ( $rev->userCan( Revision::DELETED_TEXT ) ) {
 639                         $link = Linker::linkKnown(
 640                                 $this->title,
 641                                 $date,
 642                                 array(),
 643                                 array( 'oldid' => $rev->getId() )
 644                         );
 645                 } else {
 646                         $link = $date;
 647                 }
 648                 if ( $rev->isDeleted( Revision::DELETED_TEXT ) ) {
 649                         $link = "<span class=\"history-deleted\">$link</span>";
 650                 }
 651                 return $link;
 652         }
 653
 654         /**
 655          * Create a diff-to-current link for this revision for this page
 656          *
 657          * @param $rev Revision
 658          * @param $latest Boolean: this is the latest revision of the page?
 659          * @return String
 660          */
 661         function curLink( $rev, $latest ) {
 662                 $cur = $this->historyPage->message['cur'];
 663                 if ( $latest || !$rev->userCan( Revision::DELETED_TEXT ) ) {
 664                         return $cur;
 665                 } else {
 666                         return Linker::linkKnown(
 667                                 $this->title,
 668                                 $cur,
 669                                 array(),
 670                                 array(
 671                                         'diff' => $this->title->getLatestRevID(),
 672                                         'oldid' => $rev->getId()
 673                                 )
 674                         );
 675                 }
 676         }
 677
 678         /**
 679          * Create a diff-to-previous link for this revision for this page.
 680          *
 681          * @param $prevRev Revision: the previous revision
 682          * @param $next Mixed: the newer revision
 683          * @return String
 684          */
 685         function lastLink( $prevRev, $next ) {
 686                 $last = $this->historyPage->message['last'];
 687                 # $next may either be a Row, null, or "unkown"
 688                 $nextRev = is_object( $next ) ? new Revision( $next ) : $next;
 689                 if ( is_null( $next ) ) {
 690                         # Probably no next row
 691                         return $last;
 692                 } elseif ( $next === 'unknown' ) {
 693                         # Next row probably exists but is unknown, use an oldid=prev link
 694                         return Linker::linkKnown(
 695                                 $this->title,
 696                                 $last,
 697                                 array(),
 698                                 array(
 699                                         'diff' => $prevRev->getId(),
 700                                         'oldid' => 'prev'
 701                                 )
 702                         );
 703                 } elseif ( !$prevRev->userCan( Revision::DELETED_TEXT )
 704                         || !$nextRev->userCan( Revision::DELETED_TEXT ) )
 705                 {
 706                         return $last;
 707                 } else {
 708                         return Linker::linkKnown(
 709                                 $this->title,
 710                                 $last,
 711                                 array(),
 712                                 array(
 713                                         'diff' => $prevRev->getId(),
 714                                         'oldid' => $next->rev_id
 715                                 )
 716                         );
 717                 }
 718         }
 719
 720         /**
 721          * Create radio buttons for page history
 722          *
 723          * @param $rev Revision object
 724          * @param $firstInList Boolean: is this version the first one?
 725          *
 726          * @return String: HTML output for the radio buttons
 727          */
 728         function diffButtons( $rev, $firstInList ) {
 729                 if ( $this->getNumRows() > 1 ) {
 730                         $id = $rev->getId();
 731                         $radio = array( 'type'  => 'radio', 'value' => $id );
 732                         /** @todo: move title texts to javascript */
 733                         if ( $firstInList ) {
 734                                 $first = Xml::element( 'input',
 735                                         array_merge( $radio, array(
 736                                                 'style' => 'visibility:hidden',
 737                                                 'name'  => 'oldid',
 738                                                 'id' => 'mw-oldid-null' ) )
 739                                 );
 740                                 $checkmark = array( 'checked' => 'checked' );
 741                         } else {
 742                                 # Check visibility of old revisions
 743                                 if ( !$rev->userCan( Revision::DELETED_TEXT ) ) {
 744                                         $radio['disabled'] = 'disabled';
 745                                         $checkmark = array(); // We will check the next possible one
 746                                 } elseif ( !$this->oldIdChecked ) {
 747                                         $checkmark = array( 'checked' => 'checked' );
 748                                         $this->oldIdChecked = $id;
 749                                 } else {
 750                                         $checkmark = array();
 751                                 }
 752                                 $first = Xml::element( 'input',
 753                                         array_merge( $radio, $checkmark, array(
 754                                                 'name'  => 'oldid',
 755                                                 'id' => "mw-oldid-$id" ) ) );
 756                                 $checkmark = array();
 757                         }
 758                         $second = Xml::element( 'input',
 759                                 array_merge( $radio, $checkmark, array(
 760                                         'name'  => 'diff',
 761                                         'id' => "mw-diff-$id" ) ) );
 762                         return $first . $second;
 763                 } else {
 764                         return '';
 765                 }
 766         }
 767
 768         /**
 769          * This is called if a write operation is possible from the generated HTML
 770          */
 771         function preventClickjacking( $enable = true ) {
 772                 $this->preventClickjacking = $enable;
 773         }
 774
 775         /**
 776          * Get the "prevent clickjacking" flag
 777          */
 778         function getPreventClickjacking() {
 779                 return $this->preventClickjacking;
 780         }
 781 }
 782
 783 /**
 784  * Backwards-compatibility aliases
 785  */
 786 class PageHistory extends HistoryPage {}
 787 class PageHistoryPager extends HistoryPager {}