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