includes/actions/HistoryAction.php

   1 <?php
   2 /**
   3  * Page history
   4  *
   5  * Split off from Article.php and Skin.php, 2003-12-22
   6  *
   7  * This program is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License as published by
   9  * the Free Software Foundation; either version 2 of the License, or
  10  * (at your option) any later version.
  11  *
  12  * This program is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  15  * GNU General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU General Public License along
  18  * with this program; if not, write to the Free Software Foundation, Inc.,
  19  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  20  * http://www.gnu.org/copyleft/gpl.html
  21  *
  22  * @file
  23  * @ingroup Actions
  24  */
  25
  26 /**
  27  * This class handles printing the history page for an article. In order to
  28  * be efficient, it uses timestamps rather than offsets for paging, to avoid
  29  * costly LIMIT,offset queries.
  30  *
  31  * Construct it by passing in an Article, and call $h->history() to print the
  32  * history.
  33  *
  34  * @ingroup Actions
  35  */
  36 class HistoryAction extends FormlessAction {
  37         const DIR_PREV = 0;
  38         const DIR_NEXT = 1;
  39
  40         /** @var array Array of message keys and strings */
  41         public $message;
  42
  43         public function getName() {
  44                 return 'history';
  45         }
  46
  47         public function requiresWrite() {
  48                 return false;
  49         }
  50
  51         public function requiresUnblock() {
  52                 return false;
  53         }
  54
  55         protected function getPageTitle() {
  56                 return $this->msg( 'history-title', $this->getTitle()->getPrefixedText() )->text();
  57         }
  58
  59         protected function getDescription() {
  60                 // Creation of a subtitle link pointing to [[Special:Log]]
  61                 return Linker::linkKnown(
  62                         SpecialPage::getTitleFor( 'Log' ),
  63                         $this->msg( 'viewpagelogs' )->escaped(),
  64                         array(),
  65                         array( 'page' => $this->getTitle()->getPrefixedText() )
  66                 );
  67         }
  68
  69         /**
  70          * @return WikiPage|Article|ImagePage|CategoryPage|Page The Article object we are working on.
  71          */
  72         public function getArticle() {
  73                 return $this->page;
  74         }
  75
  76         /**
  77          * As we use the same small set of messages in various methods and that
  78          * they are called often, we call them once and save them in $this->message
  79          */
  80         private function preCacheMessages() {
  81                 // Precache various messages
  82                 if ( !isset( $this->message ) ) {
  83                         $msgs = array( 'cur', 'last', 'pipe-separator' );
  84                         foreach ( $msgs as $msg ) {
  85                                 $this->message[$msg] = $this->msg( $msg )->escaped();
  86                         }
  87                 }
  88         }
  89
  90         /**
  91          * Print the history page for an article.
  92          */
  93         function onView() {
  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                 $this->preCacheMessages();
 105                 $config = $this->context->getConfig();
 106
 107                 # Fill in the file cache if not set already
 108                 $useFileCache = $config->get( 'UseFileCache' );
 109                 if ( $useFileCache && HTMLFileCache::useFileCache( $this->getContext() ) ) {
 110                         $cache = new HTMLFileCache( $this->getTitle(), 'history' );
 111                         if ( !$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                 if ( $config->get( 'UseMediaWikiUIEverywhere' ) ) {
 120                         $out = $this->getOutput();
 121                         $out->addModuleStyles( array(
 122                                 'mediawiki.ui.input',
 123                                 'mediawiki.ui.checkbox',
 124                         ) );
 125                 }
 126
 127                 // Handle atom/RSS feeds.
 128                 $feedType = $request->getVal( 'feed' );
 129                 if ( $feedType ) {
 130                         $this->feed( $feedType );
 131
 132                         return;
 133                 }
 134
 135                 // Fail nicely if article doesn't exist.
 136                 if ( !$this->page->exists() ) {
 137                         $out->addWikiMsg( 'nohistory' );
 138                         # show deletion/move log if there is an entry
 139                         LogEventsList::showLogExtract(
 140                                 $out,
 141                                 array( 'delete', 'move' ),
 142                                 $this->getTitle(),
 143                                 '',
 144                                 array( 'lim' => 10,
 145                                         'conds' => array( "log_action != 'revision'" ),
 146                                         'showIfEmpty' => false,
 147                                         'msgKey' => array( 'moveddeleted-notice' )
 148                                 )
 149                         );
 150
 151                         return;
 152                 }
 153
 154                 /**
 155                  * Add date selector to quickly get to a certain time
 156                  */
 157                 $year = $request->getInt( 'year' );
 158                 $month = $request->getInt( 'month' );
 159                 $tagFilter = $request->getVal( 'tagfilter' );
 160                 $tagSelector = ChangeTags::buildTagFilterSelector( $tagFilter );
 161
 162                 /**
 163                  * Option to show only revisions that have been (partially) hidden via RevisionDelete
 164                  */
 165                 if ( $request->getBool( 'deleted' ) ) {
 166                         $conds = array( 'rev_deleted != 0' );
 167                 } else {
 168                         $conds = array();
 169                 }
 170                 if ( $this->getUser()->isAllowed( 'deletedhistory' ) ) {
 171                         $checkDeleted = Xml::checkLabel( $this->msg( 'history-show-deleted' )->text(),
 172                                 'deleted', 'mw-show-deleted-only', $request->getBool( 'deleted' ) ) . "\n";
 173                 } else {
 174                         $checkDeleted = '';
 175                 }
 176
 177                 // Add the general form
 178                 $action = htmlspecialchars( wfScript() );
 179                 $out->addHTML(
 180                         "<form action=\"$action\" method=\"get\" id=\"mw-history-searchform\">" .
 181                         Xml::fieldset(
 182                                 $this->msg( 'history-fieldset-title' )->text(),
 183                                 false,
 184                                 array( 'id' => 'mw-history-search' )
 185                         ) .
 186                         Html::hidden( 'title', $this->getTitle()->getPrefixedDBkey() ) . "\n" .
 187                         Html::hidden( 'action', 'history' ) . "\n" .
 188                         Xml::dateMenu(
 189                                 ( $year == null ? MWTimestamp::getLocalInstance()->format( 'Y' ) : $year ),
 190                                 $month
 191                         ) . '&#160;' .
 192                         ( $tagSelector ? ( implode( '&#160;', $tagSelector ) . '&#160;' ) : '' ) .
 193                         $checkDeleted .
 194                         Html::submitButton(
 195                                 $this->msg( 'allpagessubmit' )->text(),
 196                                 array(),
 197                                 array( 'mw-ui-progressive' )
 198                         ) . "\n" .
 199                         '</fieldset></form>'
 200                 );
 201
 202                 Hooks::run( 'PageHistoryBeforeList', array( &$this->page, $this->getContext() ) );
 203
 204                 // Create and output the list.
 205                 $pager = new HistoryPager( $this, $year, $month, $tagFilter, $conds );
 206                 $out->addHTML(
 207                         $pager->getNavigationBar() .
 208                         $pager->getBody() .
 209                         $pager->getNavigationBar()
 210                 );
 211                 $out->preventClickjacking( $pager->getPreventClickjacking() );
 212
 213         }
 214
 215         /**
 216          * Fetch an array of revisions, specified by a given limit, offset and
 217          * direction. This is now only used by the feeds. It was previously
 218          * used by the main UI but that's now handled by the pager.
 219          *
 220          * @param int $limit The limit number of revisions to get
 221          * @param int $offset
 222          * @param int $direction Either self::DIR_PREV or self::DIR_NEXT
 223          * @return ResultWrapper
 224          */
 225         function fetchRevisions( $limit, $offset, $direction ) {
 226                 // Fail if article doesn't exist.
 227                 if ( !$this->getTitle()->exists() ) {
 228                         return new FakeResultWrapper( array() );
 229                 }
 230
 231                 $dbr = wfGetDB( DB_SLAVE );
 232
 233                 if ( $direction === self::DIR_PREV ) {
 234                         list( $dirs, $oper ) = array( "ASC", ">=" );
 235                 } else { /* $direction === self::DIR_NEXT */
 236                         list( $dirs, $oper ) = array( "DESC", "<=" );
 237                 }
 238
 239                 if ( $offset ) {
 240                         $offsets = array( "rev_timestamp $oper " . $dbr->addQuotes( $dbr->timestamp( $offset ) ) );
 241                 } else {
 242                         $offsets = array();
 243                 }
 244
 245                 $page_id = $this->page->getId();
 246
 247                 return $dbr->select( 'revision',
 248                         Revision::selectFields(),
 249                         array_merge( array( 'rev_page' => $page_id ), $offsets ),
 250                         __METHOD__,
 251                         array( 'ORDER BY' => "rev_timestamp $dirs",
 252                                 'USE INDEX' => 'page_timestamp', 'LIMIT' => $limit )
 253                 );
 254         }
 255
 256         /**
 257          * Output a subscription feed listing recent edits to this page.
 258          *
 259          * @param string $type Feed type
 260          */
 261         function feed( $type ) {
 262                 if ( !FeedUtils::checkFeedOutput( $type ) ) {
 263                         return;
 264                 }
 265                 $request = $this->getRequest();
 266
 267                 $feedClasses = $this->context->getConfig()->get( 'FeedClasses' );
 268                 /** @var RSSFeed|AtomFeed $feed */
 269                 $feed = new $feedClasses[$type](
 270                         $this->getTitle()->getPrefixedText() . ' - ' .
 271                         $this->msg( 'history-feed-title' )->inContentLanguage()->text(),
 272                         $this->msg( 'history-feed-description' )->inContentLanguage()->text(),
 273                         $this->getTitle()->getFullURL( 'action=history' )
 274                 );
 275
 276                 // Get a limit on number of feed entries. Provide a sane default
 277                 // of 10 if none is defined (but limit to $wgFeedLimit max)
 278                 $limit = $request->getInt( 'limit', 10 );
 279                 $limit = min(
 280                         max( $limit, 1 ),
 281                         $this->context->getConfig()->get( 'FeedLimit' )
 282                 );
 283
 284                 $items = $this->fetchRevisions( $limit, 0, self::DIR_NEXT );
 285
 286                 // Generate feed elements enclosed between header and footer.
 287                 $feed->outHeader();
 288                 if ( $items->numRows() ) {
 289                         foreach ( $items as $row ) {
 290                                 $feed->outItem( $this->feedItem( $row ) );
 291                         }
 292                 } else {
 293                         $feed->outItem( $this->feedEmpty() );
 294                 }
 295                 $feed->outFooter();
 296         }
 297
 298         function feedEmpty() {
 299                 return new FeedItem(
 300                         $this->msg( 'nohistory' )->inContentLanguage()->text(),
 301                         $this->msg( 'history-feed-empty' )->inContentLanguage()->parseAsBlock(),
 302                         $this->getTitle()->getFullURL(),
 303                         wfTimestamp( TS_MW ),
 304                         '',
 305                         $this->getTitle()->getTalkPage()->getFullURL()
 306                 );
 307         }
 308
 309         /**
 310          * Generate a FeedItem object from a given revision table row
 311          * Borrows Recent Changes' feed generation functions for formatting;
 312          * includes a diff to the previous revision (if any).
 313          *
 314          * @param stdClass|array $row Database row
 315          * @return FeedItem
 316          */
 317         function feedItem( $row ) {
 318                 $rev = new Revision( $row );
 319                 $rev->setTitle( $this->getTitle() );
 320                 $text = FeedUtils::formatDiffRow(
 321                         $this->getTitle(),
 322                         $this->getTitle()->getPreviousRevisionID( $rev->getId() ),
 323                         $rev->getId(),
 324                         $rev->getTimestamp(),
 325                         $rev->getComment()
 326                 );
 327                 if ( $rev->getComment() == '' ) {
 328                         global $wgContLang;
 329                         $title = $this->msg( 'history-feed-item-nocomment',
 330                                 $rev->getUserText(),
 331                                 $wgContLang->timeanddate( $rev->getTimestamp() ),
 332                                 $wgContLang->date( $rev->getTimestamp() ),
 333                                 $wgContLang->time( $rev->getTimestamp() ) )->inContentLanguage()->text();
 334                 } else {
 335                         $title = $rev->getUserText() .
 336                                 $this->msg( 'colon-separator' )->inContentLanguage()->text() .
 337                                 FeedItem::stripComment( $rev->getComment() );
 338                 }
 339
 340                 return new FeedItem(
 341                         $title,
 342                         $text,
 343                         $this->getTitle()->getFullURL( 'diff=' . $rev->getId() . '&oldid=prev' ),
 344                         $rev->getTimestamp(),
 345                         $rev->getUserText(),
 346                         $this->getTitle()->getTalkPage()->getFullURL()
 347                 );
 348         }
 349 }
 350
 351 /**
 352  * @ingroup Pager
 353  * @ingroup Actions
 354  */
 355 class HistoryPager extends ReverseChronologicalPager {
 356         /**
 357          * @var bool|stdClass
 358          */
 359         public $lastRow = false;
 360
 361         public $counter, $historyPage, $buttons, $conds;
 362
 363         protected $oldIdChecked;
 364
 365         protected $preventClickjacking = false;
 366         /**
 367          * @var array
 368          */
 369         protected $parentLens;
 370
 371         /**
 372          * @param HistoryAction $historyPage
 373          * @param string $year
 374          * @param string $month
 375          * @param string $tagFilter
 376          * @param array $conds
 377          */
 378         function __construct( $historyPage, $year = '', $month = '', $tagFilter = '', $conds = array() ) {
 379                 parent::__construct( $historyPage->getContext() );
 380                 $this->historyPage = $historyPage;
 381                 $this->tagFilter = $tagFilter;
 382                 $this->getDateCond( $year, $month );
 383                 $this->conds = $conds;
 384         }
 385
 386         // For hook compatibility...
 387         function getArticle() {
 388                 return $this->historyPage->getArticle();
 389         }
 390
 391         function getSqlComment() {
 392                 if ( $this->conds ) {
 393                         return 'history page filtered'; // potentially slow, see CR r58153
 394                 } else {
 395                         return 'history page unfiltered';
 396                 }
 397         }
 398
 399         function getQueryInfo() {
 400                 $queryInfo = array(
 401                         'tables' => array( 'revision', 'user' ),
 402                         'fields' => array_merge( Revision::selectFields(), Revision::selectUserFields() ),
 403                         'conds' => array_merge(
 404                                 array( 'rev_page' => $this->getWikiPage()->getId() ),
 405                                 $this->conds ),
 406                         'options' => array( 'USE INDEX' => array( 'revision' => 'page_timestamp' ) ),
 407                         'join_conds' => array( 'user' => Revision::userJoinCond() ),
 408                 );
 409                 ChangeTags::modifyDisplayQuery(
 410                         $queryInfo['tables'],
 411                         $queryInfo['fields'],
 412                         $queryInfo['conds'],
 413                         $queryInfo['join_conds'],
 414                         $queryInfo['options'],
 415                         $this->tagFilter
 416                 );
 417                 Hooks::run( 'PageHistoryPager::getQueryInfo', array( &$this, &$queryInfo ) );
 418
 419                 return $queryInfo;
 420         }
 421
 422         function getIndexField() {
 423                 return 'rev_timestamp';
 424         }
 425
 426         /**
 427          * @param stdClass $row
 428          * @return string
 429          */
 430         function formatRow( $row ) {
 431                 if ( $this->lastRow ) {
 432                         $latest = ( $this->counter == 1 && $this->mIsFirst );
 433                         $firstInList = $this->counter == 1;
 434                         $this->counter++;
 435
 436                         $notifTimestamp = $this->getConfig()->get( 'ShowUpdatedMarker' )
 437                                 ? $this->getTitle()->getNotificationTimestamp( $this->getUser() )
 438                                 : false;
 439
 440                         $s = $this->historyLine(
 441                                 $this->lastRow, $row, $notifTimestamp, $latest, $firstInList );
 442                 } else {
 443                         $s = '';
 444                 }
 445                 $this->lastRow = $row;
 446
 447                 return $s;
 448         }
 449
 450         function doBatchLookups() {
 451                 # Do a link batch query
 452                 $this->mResult->seek( 0 );
 453                 $batch = new LinkBatch();
 454                 $revIds = array();
 455                 foreach ( $this->mResult as $row ) {
 456                         if ( $row->rev_parent_id ) {
 457                                 $revIds[] = $row->rev_parent_id;
 458                         }
 459                         if ( !is_null( $row->user_name ) ) {
 460                                 $batch->add( NS_USER, $row->user_name );
 461                                 $batch->add( NS_USER_TALK, $row->user_name );
 462                         } else { # for anons or usernames of imported revisions
 463                                 $batch->add( NS_USER, $row->rev_user_text );
 464                                 $batch->add( NS_USER_TALK, $row->rev_user_text );
 465                         }
 466                 }
 467                 $this->parentLens = Revision::getParentLengths( $this->mDb, $revIds );
 468                 $batch->execute();
 469                 $this->mResult->seek( 0 );
 470         }
 471
 472         /**
 473          * Creates begin of history list with a submit button
 474          *
 475          * @return string HTML output
 476          */
 477         function getStartBody() {
 478                 $this->lastRow = false;
 479                 $this->counter = 1;
 480                 $this->oldIdChecked = 0;
 481
 482                 $this->getOutput()->wrapWikiMsg( "<div class='mw-history-legend'>\n$1\n</div>", 'histlegend' );
 483                 $s = Html::openElement( 'form', array( 'action' => wfScript(),
 484                         'id' => 'mw-history-compare' ) ) . "\n";
 485                 $s .= Html::hidden( 'title', $this->getTitle()->getPrefixedDBkey() ) . "\n";
 486                 $s .= Html::hidden( 'action', 'historysubmit' ) . "\n";
 487                 $s .= Html::hidden( 'type', 'revision' ) . "\n";
 488
 489                 // Button container stored in $this->buttons for re-use in getEndBody()
 490                 $this->buttons = '<div>';
 491                 $className = 'historysubmit mw-history-compareselectedversions-button';
 492                 $attrs = array( 'class' => $className )
 493                         + Linker::tooltipAndAccesskeyAttribs( 'compareselectedversions' );
 494                 $this->buttons .= $this->submitButton( $this->msg( 'compareselectedversions' )->text(),
 495                         $attrs
 496                 ) . "\n";
 497
 498                 $user = $this->getUser();
 499                 $actionButtons = '';
 500                 if ( $user->isAllowed( 'deleterevision' ) ) {
 501                         $actionButtons .= $this->getRevisionButton( 'revisiondelete', 'showhideselectedversions' );
 502                 }
 503                 if ( $user->isAllowed( 'changetags' ) ) {
 504                         $actionButtons .= $this->getRevisionButton( 'editchangetags', 'history-edit-tags' );
 505                 }
 506                 if ( $actionButtons ) {
 507                         $this->buttons .= Xml::tags( 'div', array( 'class' =>
 508                                 'mw-history-revisionactions' ), $actionButtons );
 509                 }
 510                 $this->buttons .= '</div>';
 511
 512                 $s .= $this->buttons;
 513                 $s .= '<ul id="pagehistory">' . "\n";
 514
 515                 return $s;
 516         }
 517
 518         private function getRevisionButton( $name, $msg ) {
 519                 $this->preventClickjacking();
 520                 # Note bug #20966, <button> is non-standard in IE<8
 521                 $element = Html::element(
 522                         'button',
 523                         array(
 524                                 'type' => 'submit',
 525                                 'name' => $name,
 526                                 'value' => '1',
 527                                 'class' => "historysubmit mw-history-$name-button",
 528                         ),
 529                         $this->msg( $msg )->text()
 530                 ) . "\n";
 531                 return $element;
 532         }
 533
 534         function getEndBody() {
 535                 if ( $this->lastRow ) {
 536                         $latest = $this->counter == 1 && $this->mIsFirst;
 537                         $firstInList = $this->counter == 1;
 538                         if ( $this->mIsBackwards ) {
 539                                 # Next row is unknown, but for UI reasons, probably exists if an offset has been specified
 540                                 if ( $this->mOffset == '' ) {
 541                                         $next = null;
 542                                 } else {
 543                                         $next = 'unknown';
 544                                 }
 545                         } else {
 546                                 # The next row is the past-the-end row
 547                                 $next = $this->mPastTheEndRow;
 548                         }
 549                         $this->counter++;
 550
 551                         $notifTimestamp = $this->getConfig()->get( 'ShowUpdatedMarker' )
 552                                 ? $this->getTitle()->getNotificationTimestamp( $this->getUser() )
 553                                 : false;
 554
 555                         $s = $this->historyLine(
 556                                 $this->lastRow, $next, $notifTimestamp, $latest, $firstInList );
 557                 } else {
 558                         $s = '';
 559                 }
 560                 $s .= "</ul>\n";
 561                 # Add second buttons only if there is more than one rev
 562                 if ( $this->getNumRows() > 2 ) {
 563                         $s .= $this->buttons;
 564                 }
 565                 $s .= '</form>';
 566
 567                 return $s;
 568         }
 569
 570         /**
 571          * Creates a submit button
 572          *
 573          * @param string $message Text of the submit button, will be escaped
 574          * @param array $attributes Attributes
 575          * @return string HTML output for the submit button
 576          */
 577         function submitButton( $message, $attributes = array() ) {
 578                 # Disable submit button if history has 1 revision only
 579                 if ( $this->getNumRows() > 1 ) {
 580                         return Html::submitButton( $message, $attributes );
 581                 } else {
 582                         return '';
 583                 }
 584         }
 585
 586         /**
 587          * Returns a row from the history printout.
 588          *
 589          * @todo document some more, and maybe clean up the code (some params redundant?)
 590          *
 591          * @param stdClass $row The database row corresponding to the previous line.
 592          * @param mixed $next The database row corresponding to the next line
 593          *   (chronologically previous)
 594          * @param bool|string $notificationtimestamp
 595          * @param bool $latest Whether this row corresponds to the page's latest revision.
 596          * @param bool $firstInList Whether this row corresponds to the first
 597          *   displayed on this history page.
 598          * @return string HTML output for the row
 599          */
 600         function historyLine( $row, $next, $notificationtimestamp = false,
 601                 $latest = false, $firstInList = false ) {
 602                 $rev = new Revision( $row );
 603                 $rev->setTitle( $this->getTitle() );
 604
 605                 if ( is_object( $next ) ) {
 606                         $prevRev = new Revision( $next );
 607                         $prevRev->setTitle( $this->getTitle() );
 608                 } else {
 609                         $prevRev = null;
 610                 }
 611
 612                 $curlink = $this->curLink( $rev, $latest );
 613                 $lastlink = $this->lastLink( $rev, $next );
 614                 $curLastlinks = $curlink . $this->historyPage->message['pipe-separator'] . $lastlink;
 615                 $histLinks = Html::rawElement(
 616                         'span',
 617                         array( 'class' => 'mw-history-histlinks' ),
 618                         $this->msg( 'parentheses' )->rawParams( $curLastlinks )->escaped()
 619                 );
 620
 621                 $diffButtons = $this->diffButtons( $rev, $firstInList );
 622                 $s = $histLinks . $diffButtons;
 623
 624                 $link = $this->revLink( $rev );
 625                 $classes = array();
 626
 627                 $del = '';
 628                 $user = $this->getUser();
 629                 $canRevDelete = $user->isAllowed( 'deleterevision' );
 630                 $canModifyTags = $user->isAllowed( 'changetags' );
 631                 // Show checkboxes for each revision, to allow for revision deletion and
 632                 // change tags
 633                 if ( $canRevDelete || $canModifyTags ) {
 634                         $this->preventClickjacking();
 635                         // If revision was hidden from sysops and we don't need the checkbox
 636                         // for anything else, disable it
 637                         if ( !$canModifyTags && !$rev->userCan( Revision::DELETED_RESTRICTED, $user ) ) {
 638                                 $del = Xml::check( 'deleterevisions', false, array( 'disabled' => 'disabled' ) );
 639                         // Otherwise, enable the checkbox...
 640                         } else {
 641                                 $del = Xml::check( 'showhiderevisions', false,
 642                                         array( 'name' => 'ids[' . $rev->getId() . ']' ) );
 643                         }
 644                 // User can only view deleted revisions...
 645                 } elseif ( $rev->getVisibility() && $user->isAllowed( 'deletedhistory' ) ) {
 646                         // If revision was hidden from sysops, disable the link
 647                         if ( !$rev->userCan( Revision::DELETED_RESTRICTED, $user ) ) {
 648                                 $del = Linker::revDeleteLinkDisabled( false );
 649                         // Otherwise, show the link...
 650                         } else {
 651                                 $query = array( 'type' => 'revision',
 652                                         'target' => $this->getTitle()->getPrefixedDBkey(), 'ids' => $rev->getId() );
 653                                 $del .= Linker::revDeleteLink( $query,
 654                                         $rev->isDeleted( Revision::DELETED_RESTRICTED ), false );
 655                         }
 656                 }
 657                 if ( $del ) {
 658                         $s .= " $del ";
 659                 }
 660
 661                 $lang = $this->getLanguage();
 662                 $dirmark = $lang->getDirMark();
 663
 664                 $s .= " $link";
 665                 $s .= $dirmark;
 666                 $s .= " <span class='history-user'>" .
 667                         Linker::revUserTools( $rev, true ) . "</span>";
 668                 $s .= $dirmark;
 669
 670                 if ( $rev->isMinor() ) {
 671                         $s .= ' ' . ChangesList::flag( 'minor' );
 672                 }
 673
 674                 # Sometimes rev_len isn't populated
 675                 if ( $rev->getSize() !== null ) {
 676                         # Size is always public data
 677                         $prevSize = isset( $this->parentLens[$row->rev_parent_id] )
 678                                 ? $this->parentLens[$row->rev_parent_id]
 679                                 : 0;
 680                         $sDiff = ChangesList::showCharacterDifference( $prevSize, $rev->getSize() );
 681                         $fSize = Linker::formatRevisionSize( $rev->getSize() );
 682                         $s .= ' <span class="mw-changeslist-separator">. .</span> ' . "$fSize $sDiff";
 683                 }
 684
 685                 # Text following the character difference is added just before running hooks
 686                 $s2 = Linker::revComment( $rev, false, true );
 687
 688                 if ( $notificationtimestamp && ( $row->rev_timestamp >= $notificationtimestamp ) ) {
 689                         $s2 .= ' <span class="updatedmarker">' . $this->msg( 'updatedmarker' )->escaped() . '</span>';
 690                         $classes[] = 'mw-history-line-updated';
 691                 }
 692
 693                 $tools = array();
 694
 695                 # Rollback and undo links
 696                 if ( $prevRev && $this->getTitle()->quickUserCan( 'edit', $user ) ) {
 697                         if ( $latest && $this->getTitle()->quickUserCan( 'rollback', $user ) ) {
 698                                 // Get a rollback link without the brackets
 699                                 $rollbackLink = Linker::generateRollback(
 700                                         $rev,
 701                                         $this->getContext(),
 702                                         array( 'verify', 'noBrackets' )
 703                                 );
 704                                 if ( $rollbackLink ) {
 705                                         $this->preventClickjacking();
 706                                         $tools[] = $rollbackLink;
 707                                 }
 708                         }
 709
 710                         if ( !$rev->isDeleted( Revision::DELETED_TEXT )
 711                                 && !$prevRev->isDeleted( Revision::DELETED_TEXT )
 712                         ) {
 713                                 # Create undo tooltip for the first (=latest) line only
 714                                 $undoTooltip = $latest
 715                                         ? array( 'title' => $this->msg( 'tooltip-undo' )->text() )
 716                                         : array();
 717                                 $undolink = Linker::linkKnown(
 718                                         $this->getTitle(),
 719                                         $this->msg( 'editundo' )->escaped(),
 720                                         $undoTooltip,
 721                                         array(
 722                                                 'action' => 'edit',
 723                                                 'undoafter' => $prevRev->getId(),
 724                                                 'undo' => $rev->getId()
 725                                         )
 726                                 );
 727                                 $tools[] = "<span class=\"mw-history-undo\">{$undolink}</span>";
 728                         }
 729                 }
 730                 // Allow extension to add their own links here
 731                 Hooks::run( 'HistoryRevisionTools', array( $rev, &$tools ) );
 732
 733                 if ( $tools ) {
 734                         $s2 .= ' ' . $this->msg( 'parentheses' )->rawParams( $lang->pipeList( $tools ) )->escaped();
 735                 }
 736
 737                 # Tags
 738                 list( $tagSummary, $newClasses ) = ChangeTags::formatSummaryRow( $row->ts_tags, 'history' );
 739                 $classes = array_merge( $classes, $newClasses );
 740                 if ( $tagSummary !== '' ) {
 741                         $s2 .= " $tagSummary";
 742                 }
 743
 744                 # Include separator between character difference and following text
 745                 if ( $s2 !== '' ) {
 746                         $s .= ' <span class="mw-changeslist-separator">. .</span> ' . $s2;
 747                 }
 748
 749                 Hooks::run( 'PageHistoryLineEnding', array( $this, &$row, &$s, &$classes ) );
 750
 751                 $attribs = array();
 752                 if ( $classes ) {
 753                         $attribs['class'] = implode( ' ', $classes );
 754                 }
 755
 756                 return Xml::tags( 'li', $attribs, $s ) . "\n";
 757         }
 758
 759         /**
 760          * Create a link to view this revision of the page
 761          *
 762          * @param Revision $rev
 763          * @return string
 764          */
 765         function revLink( $rev ) {
 766                 $date = $this->getLanguage()->userTimeAndDate( $rev->getTimestamp(), $this->getUser() );
 767                 $date = htmlspecialchars( $date );
 768                 if ( $rev->userCan( Revision::DELETED_TEXT, $this->getUser() ) ) {
 769                         $link = Linker::linkKnown(
 770                                 $this->getTitle(),
 771                                 $date,
 772                                 array( 'class' => 'mw-changeslist-date' ),
 773                                 array( 'oldid' => $rev->getId() )
 774                         );
 775                 } else {
 776                         $link = $date;
 777                 }
 778                 if ( $rev->isDeleted( Revision::DELETED_TEXT ) ) {
 779                         $link = "<span class=\"history-deleted\">$link</span>";
 780                 }
 781
 782                 return $link;
 783         }
 784
 785         /**
 786          * Create a diff-to-current link for this revision for this page
 787          *
 788          * @param Revision $rev
 789          * @param bool $latest This is the latest revision of the page?
 790          * @return string
 791          */
 792         function curLink( $rev, $latest ) {
 793                 $cur = $this->historyPage->message['cur'];
 794                 if ( $latest || !$rev->userCan( Revision::DELETED_TEXT, $this->getUser() ) ) {
 795                         return $cur;
 796                 } else {
 797                         return Linker::linkKnown(
 798                                 $this->getTitle(),
 799                                 $cur,
 800                                 array(),
 801                                 array(
 802                                         'diff' => $this->getWikiPage()->getLatest(),
 803                                         'oldid' => $rev->getId()
 804                                 )
 805                         );
 806                 }
 807         }
 808
 809         /**
 810          * Create a diff-to-previous link for this revision for this page.
 811          *
 812          * @param Revision $prevRev The revision being displayed
 813          * @param stdClass|string|null $next The next revision in list (that is
 814          *        the previous one in chronological order).
 815          *        May either be a row, "unknown" or null.
 816          * @return string
 817          */
 818         function lastLink( $prevRev, $next ) {
 819                 $last = $this->historyPage->message['last'];
 820
 821                 if ( $next === null ) {
 822                         # Probably no next row
 823                         return $last;
 824                 }
 825
 826                 if ( $next === 'unknown' ) {
 827                         # Next row probably exists but is unknown, use an oldid=prev link
 828                         return Linker::linkKnown(
 829                                 $this->getTitle(),
 830                                 $last,
 831                                 array(),
 832                                 array(
 833                                         'diff' => $prevRev->getId(),
 834                                         'oldid' => 'prev'
 835                                 )
 836                         );
 837                 }
 838
 839                 $nextRev = new Revision( $next );
 840
 841                 if ( !$prevRev->userCan( Revision::DELETED_TEXT, $this->getUser() )
 842                         || !$nextRev->userCan( Revision::DELETED_TEXT, $this->getUser() )
 843                 ) {
 844                         return $last;
 845                 }
 846
 847                 return Linker::linkKnown(
 848                         $this->getTitle(),
 849                         $last,
 850                         array(),
 851                         array(
 852                                 'diff' => $prevRev->getId(),
 853                                 'oldid' => $next->rev_id
 854                         )
 855                 );
 856         }
 857
 858         /**
 859          * Create radio buttons for page history
 860          *
 861          * @param Revision $rev
 862          * @param bool $firstInList Is this version the first one?
 863          *
 864          * @return string HTML output for the radio buttons
 865          */
 866         function diffButtons( $rev, $firstInList ) {
 867                 if ( $this->getNumRows() > 1 ) {
 868                         $id = $rev->getId();
 869                         $radio = array( 'type' => 'radio', 'value' => $id );
 870                         /** @todo Move title texts to javascript */
 871                         if ( $firstInList ) {
 872                                 $first = Xml::element( 'input',
 873                                         array_merge( $radio, array(
 874                                                 'style' => 'visibility:hidden',
 875                                                 'name' => 'oldid',
 876                                                 'id' => 'mw-oldid-null' ) )
 877                                 );
 878                                 $checkmark = array( 'checked' => 'checked' );
 879                         } else {
 880                                 # Check visibility of old revisions
 881                                 if ( !$rev->userCan( Revision::DELETED_TEXT, $this->getUser() ) ) {
 882                                         $radio['disabled'] = 'disabled';
 883                                         $checkmark = array(); // We will check the next possible one
 884                                 } elseif ( !$this->oldIdChecked ) {
 885                                         $checkmark = array( 'checked' => 'checked' );
 886                                         $this->oldIdChecked = $id;
 887                                 } else {
 888                                         $checkmark = array();
 889                                 }
 890                                 $first = Xml::element( 'input',
 891                                         array_merge( $radio, $checkmark, array(
 892                                                 'name' => 'oldid',
 893                                                 'id' => "mw-oldid-$id" ) ) );
 894                                 $checkmark = array();
 895                         }
 896                         $second = Xml::element( 'input',
 897                                 array_merge( $radio, $checkmark, array(
 898                                         'name' => 'diff',
 899                                         'id' => "mw-diff-$id" ) ) );
 900
 901                         return $first . $second;
 902                 } else {
 903                         return '';
 904                 }
 905         }
 906
 907         /**
 908          * This is called if a write operation is possible from the generated HTML
 909          * @param bool $enable
 910          */
 911         function preventClickjacking( $enable = true ) {
 912                 $this->preventClickjacking = $enable;
 913         }
 914
 915         /**
 916          * Get the "prevent clickjacking" flag
 917          * @return bool
 918          */
 919         function getPreventClickjacking() {
 920                 return $this->preventClickjacking;
 921         }
 922
 923 }