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