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                         [],
  65                         [ '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 = [ '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                 if ( HTMLFileCache::useFileCache( $this->getContext() ) ) {
 109                         $cache = new HTMLFileCache( $this->getTitle(), 'history' );
 110                         if ( !$cache->isCacheGood( /* Assume up to date */ ) ) {
 111                                 ob_start( [ &$cache, 'saveToFileCache' ] );
 112                         }
 113                 }
 114
 115                 // Setup page variables.
 116                 $out->setFeedAppendQuery( 'action=history' );
 117                 $out->addModules( 'mediawiki.action.history' );
 118                 $out->addModuleStyles( [
 119                         'mediawiki.action.history.styles',
 120                         'mediawiki.special.changeslist',
 121                 ] );
 122                 if ( $config->get( 'UseMediaWikiUIEverywhere' ) ) {
 123                         $out = $this->getOutput();
 124                         $out->addModuleStyles( [
 125                                 'mediawiki.ui.input',
 126                                 'mediawiki.ui.checkbox',
 127                         ] );
 128                 }
 129
 130                 // Handle atom/RSS feeds.
 131                 $feedType = $request->getVal( 'feed' );
 132                 if ( $feedType ) {
 133                         $this->feed( $feedType );
 134
 135                         return;
 136                 }
 137
 138                 $this->addHelpLink( '//meta.wikimedia.org/wiki/Special:MyLanguage/Help:Page_history', true );
 139
 140                 // Fail nicely if article doesn't exist.
 141                 if ( !$this->page->exists() ) {
 142                         global $wgSend404Code;
 143                         if ( $wgSend404Code ) {
 144                                 $out->setStatusCode( 404 );
 145                         }
 146                         $out->addWikiMsg( 'nohistory' );
 147                         # show deletion/move log if there is an entry
 148                         LogEventsList::showLogExtract(
 149                                 $out,
 150                                 [ 'delete', 'move' ],
 151                                 $this->getTitle(),
 152                                 '',
 153                                 [ 'lim' => 10,
 154                                         'conds' => [ "log_action != 'revision'" ],
 155                                         'showIfEmpty' => false,
 156                                         'msgKey' => [ 'moveddeleted-notice' ]
 157                                 ]
 158                         );
 159
 160                         return;
 161                 }
 162
 163                 /**
 164                  * Add date selector to quickly get to a certain time
 165                  */
 166                 $year = $request->getInt( 'year' );
 167                 $month = $request->getInt( 'month' );
 168                 $tagFilter = $request->getVal( 'tagfilter' );
 169                 $tagSelector = ChangeTags::buildTagFilterSelector( $tagFilter );
 170
 171                 /**
 172                  * Option to show only revisions that have been (partially) hidden via RevisionDelete
 173                  */
 174                 if ( $request->getBool( 'deleted' ) ) {
 175                         $conds = [ 'rev_deleted != 0' ];
 176                 } else {
 177                         $conds = [];
 178                 }
 179                 if ( $this->getUser()->isAllowed( 'deletedhistory' ) ) {
 180                         $checkDeleted = Xml::checkLabel( $this->msg( 'history-show-deleted' )->text(),
 181                                 'deleted', 'mw-show-deleted-only', $request->getBool( 'deleted' ) ) . "\n";
 182                 } else {
 183                         $checkDeleted = '';
 184                 }
 185
 186                 // Add the general form
 187                 $action = htmlspecialchars( wfScript() );
 188                 $out->addHTML(
 189                         "<form action=\"$action\" method=\"get\" id=\"mw-history-searchform\">" .
 190                         Xml::fieldset(
 191                                 $this->msg( 'history-fieldset-title' )->text(),
 192                                 false,
 193                                 [ 'id' => 'mw-history-search' ]
 194                         ) .
 195                         Html::hidden( 'title', $this->getTitle()->getPrefixedDBkey() ) . "\n" .
 196                         Html::hidden( 'action', 'history' ) . "\n" .
 197                         Xml::dateMenu(
 198                                 ( $year == null ? MWTimestamp::getLocalInstance()->format( 'Y' ) : $year ),
 199                                 $month
 200                         ) . '&#160;' .
 201                         ( $tagSelector ? ( implode( '&#160;', $tagSelector ) . '&#160;' ) : '' ) .
 202                         $checkDeleted .
 203                         Html::submitButton(
 204                                 $this->msg( 'historyaction-submit' )->text(),
 205                                 [],
 206                                 [ 'mw-ui-progressive' ]
 207                         ) . "\n" .
 208                         '</fieldset></form>'
 209                 );
 210
 211                 Hooks::run( 'PageHistoryBeforeList', [ &$this->page, $this->getContext() ] );
 212
 213                 // Create and output the list.
 214                 $pager = new HistoryPager( $this, $year, $month, $tagFilter, $conds );
 215                 $out->addHTML(
 216                         $pager->getNavigationBar() .
 217                         $pager->getBody() .
 218                         $pager->getNavigationBar()
 219                 );
 220                 $out->preventClickjacking( $pager->getPreventClickjacking() );
 221
 222         }
 223
 224         /**
 225          * Fetch an array of revisions, specified by a given limit, offset and
 226          * direction. This is now only used by the feeds. It was previously
 227          * used by the main UI but that's now handled by the pager.
 228          *
 229          * @param int $limit The limit number of revisions to get
 230          * @param int $offset
 231          * @param int $direction Either self::DIR_PREV or self::DIR_NEXT
 232          * @return ResultWrapper
 233          */
 234         function fetchRevisions( $limit, $offset, $direction ) {
 235                 // Fail if article doesn't exist.
 236                 if ( !$this->getTitle()->exists() ) {
 237                         return new FakeResultWrapper( [] );
 238                 }
 239
 240                 $dbr = wfGetDB( DB_REPLICA );
 241
 242                 if ( $direction === self::DIR_PREV ) {
 243                         list( $dirs, $oper ) = [ "ASC", ">=" ];
 244                 } else { /* $direction === self::DIR_NEXT */
 245                         list( $dirs, $oper ) = [ "DESC", "<=" ];
 246                 }
 247
 248                 if ( $offset ) {
 249                         $offsets = [ "rev_timestamp $oper " . $dbr->addQuotes( $dbr->timestamp( $offset ) ) ];
 250                 } else {
 251                         $offsets = [];
 252                 }
 253
 254                 $page_id = $this->page->getId();
 255
 256                 return $dbr->select( 'revision',
 257                         Revision::selectFields(),
 258                         array_merge( [ 'rev_page' => $page_id ], $offsets ),
 259                         __METHOD__,
 260                         [ 'ORDER BY' => "rev_timestamp $dirs",
 261                                 'USE INDEX' => 'page_timestamp', 'LIMIT' => $limit ]
 262                 );
 263         }
 264
 265         /**
 266          * Output a subscription feed listing recent edits to this page.
 267          *
 268          * @param string $type Feed type
 269          */
 270         function feed( $type ) {
 271                 if ( !FeedUtils::checkFeedOutput( $type ) ) {
 272                         return;
 273                 }
 274                 $request = $this->getRequest();
 275
 276                 $feedClasses = $this->context->getConfig()->get( 'FeedClasses' );
 277                 /** @var RSSFeed|AtomFeed $feed */
 278                 $feed = new $feedClasses[$type](
 279                         $this->getTitle()->getPrefixedText() . ' - ' .
 280                         $this->msg( 'history-feed-title' )->inContentLanguage()->text(),
 281                         $this->msg( 'history-feed-description' )->inContentLanguage()->text(),
 282                         $this->getTitle()->getFullURL( 'action=history' )
 283                 );
 284
 285                 // Get a limit on number of feed entries. Provide a sane default
 286                 // of 10 if none is defined (but limit to $wgFeedLimit max)
 287                 $limit = $request->getInt( 'limit', 10 );
 288                 $limit = min(
 289                         max( $limit, 1 ),
 290                         $this->context->getConfig()->get( 'FeedLimit' )
 291                 );
 292
 293                 $items = $this->fetchRevisions( $limit, 0, self::DIR_NEXT );
 294
 295                 // Generate feed elements enclosed between header and footer.
 296                 $feed->outHeader();
 297                 if ( $items->numRows() ) {
 298                         foreach ( $items as $row ) {
 299                                 $feed->outItem( $this->feedItem( $row ) );
 300                         }
 301                 } else {
 302                         $feed->outItem( $this->feedEmpty() );
 303                 }
 304                 $feed->outFooter();
 305         }
 306
 307         function feedEmpty() {
 308                 return new FeedItem(
 309                         $this->msg( 'nohistory' )->inContentLanguage()->text(),
 310                         $this->msg( 'history-feed-empty' )->inContentLanguage()->parseAsBlock(),
 311                         $this->getTitle()->getFullURL(),
 312                         wfTimestamp( TS_MW ),
 313                         '',
 314                         $this->getTitle()->getTalkPage()->getFullURL()
 315                 );
 316         }
 317
 318         /**
 319          * Generate a FeedItem object from a given revision table row
 320          * Borrows Recent Changes' feed generation functions for formatting;
 321          * includes a diff to the previous revision (if any).
 322          *
 323          * @param stdClass|array $row Database row
 324          * @return FeedItem
 325          */
 326         function feedItem( $row ) {
 327                 $rev = new Revision( $row );
 328                 $rev->setTitle( $this->getTitle() );
 329                 $text = FeedUtils::formatDiffRow(
 330                         $this->getTitle(),
 331                         $this->getTitle()->getPreviousRevisionID( $rev->getId() ),
 332                         $rev->getId(),
 333                         $rev->getTimestamp(),
 334                         $rev->getComment()
 335                 );
 336                 if ( $rev->getComment() == '' ) {
 337                         global $wgContLang;
 338                         $title = $this->msg( 'history-feed-item-nocomment',
 339                                 $rev->getUserText(),
 340                                 $wgContLang->timeanddate( $rev->getTimestamp() ),
 341                                 $wgContLang->date( $rev->getTimestamp() ),
 342                                 $wgContLang->time( $rev->getTimestamp() ) )->inContentLanguage()->text();
 343                 } else {
 344                         $title = $rev->getUserText() .
 345                                 $this->msg( 'colon-separator' )->inContentLanguage()->text() .
 346                                 FeedItem::stripComment( $rev->getComment() );
 347                 }
 348
 349                 return new FeedItem(
 350                         $title,
 351                         $text,
 352                         $this->getTitle()->getFullURL( 'diff=' . $rev->getId() . '&oldid=prev' ),
 353                         $rev->getTimestamp(),
 354                         $rev->getUserText(),
 355                         $this->getTitle()->getTalkPage()->getFullURL()
 356                 );
 357         }
 358 }
 359
 360 /**
 361  * @ingroup Pager
 362  * @ingroup Actions
 363  */
 364 class HistoryPager extends ReverseChronologicalPager {
 365         /**
 366          * @var bool|stdClass
 367          */
 368         public $lastRow = false;
 369
 370         public $counter, $historyPage, $buttons, $conds;
 371
 372         protected $oldIdChecked;
 373
 374         protected $preventClickjacking = false;
 375         /**
 376          * @var array
 377          */
 378         protected $parentLens;
 379
 380         /** @var bool Whether to show the tag editing UI */
 381         protected $showTagEditUI;
 382
 383         /**
 384          * @param HistoryAction $historyPage
 385          * @param string $year
 386          * @param string $month
 387          * @param string $tagFilter
 388          * @param array $conds
 389          */
 390         function __construct( $historyPage, $year = '', $month = '', $tagFilter = '', $conds = [] ) {
 391                 parent::__construct( $historyPage->getContext() );
 392                 $this->historyPage = $historyPage;
 393                 $this->tagFilter = $tagFilter;
 394                 $this->getDateCond( $year, $month );
 395                 $this->conds = $conds;
 396                 $this->showTagEditUI = ChangeTags::showTagEditingUI( $this->getUser() );
 397         }
 398
 399         // For hook compatibility...
 400         function getArticle() {
 401                 return $this->historyPage->getArticle();
 402         }
 403
 404         function getSqlComment() {
 405                 if ( $this->conds ) {
 406                         return 'history page filtered'; // potentially slow, see CR r58153
 407                 } else {
 408                         return 'history page unfiltered';
 409                 }
 410         }
 411
 412         function getQueryInfo() {
 413                 $queryInfo = [
 414                         'tables' => [ 'revision', 'user' ],
 415                         'fields' => array_merge( Revision::selectFields(), Revision::selectUserFields() ),
 416                         'conds' => array_merge(
 417                                 [ 'rev_page' => $this->getWikiPage()->getId() ],
 418                                 $this->conds ),
 419                         'options' => [ 'USE INDEX' => [ 'revision' => 'page_timestamp' ] ],
 420                         'join_conds' => [ 'user' => Revision::userJoinCond() ],
 421                 ];
 422                 ChangeTags::modifyDisplayQuery(
 423                         $queryInfo['tables'],
 424                         $queryInfo['fields'],
 425                         $queryInfo['conds'],
 426                         $queryInfo['join_conds'],
 427                         $queryInfo['options'],
 428                         $this->tagFilter
 429                 );
 430                 Hooks::run( 'PageHistoryPager::getQueryInfo', [ &$this, &$queryInfo ] );
 431
 432                 return $queryInfo;
 433         }
 434
 435         function getIndexField() {
 436                 return 'rev_timestamp';
 437         }
 438
 439         /**
 440          * @param stdClass $row
 441          * @return string
 442          */
 443         function formatRow( $row ) {
 444                 if ( $this->lastRow ) {
 445                         $latest = ( $this->counter == 1 && $this->mIsFirst );
 446                         $firstInList = $this->counter == 1;
 447                         $this->counter++;
 448
 449                         $notifTimestamp = $this->getConfig()->get( 'ShowUpdatedMarker' )
 450                                 ? $this->getTitle()->getNotificationTimestamp( $this->getUser() )
 451                                 : false;
 452
 453                         $s = $this->historyLine(
 454                                 $this->lastRow, $row, $notifTimestamp, $latest, $firstInList );
 455                 } else {
 456                         $s = '';
 457                 }
 458                 $this->lastRow = $row;
 459
 460                 return $s;
 461         }
 462
 463         function doBatchLookups() {
 464                 if ( !Hooks::run( 'PageHistoryPager::doBatchLookups', [ $this, $this->mResult ] ) ) {
 465                         return;
 466                 }
 467
 468                 # Do a link batch query
 469                 $this->mResult->seek( 0 );
 470                 $batch = new LinkBatch();
 471                 $revIds = [];
 472                 foreach ( $this->mResult as $row ) {
 473                         if ( $row->rev_parent_id ) {
 474                                 $revIds[] = $row->rev_parent_id;
 475                         }
 476                         if ( !is_null( $row->user_name ) ) {
 477                                 $batch->add( NS_USER, $row->user_name );
 478                                 $batch->add( NS_USER_TALK, $row->user_name );
 479                         } else { # for anons or usernames of imported revisions
 480                                 $batch->add( NS_USER, $row->rev_user_text );
 481                                 $batch->add( NS_USER_TALK, $row->rev_user_text );
 482                         }
 483                 }
 484                 $this->parentLens = Revision::getParentLengths( $this->mDb, $revIds );
 485                 $batch->execute();
 486                 $this->mResult->seek( 0 );
 487         }
 488
 489         /**
 490          * Creates begin of history list with a submit button
 491          *
 492          * @return string HTML output
 493          */
 494         function getStartBody() {
 495                 $this->lastRow = false;
 496                 $this->counter = 1;
 497                 $this->oldIdChecked = 0;
 498
 499                 $this->getOutput()->wrapWikiMsg( "<div class='mw-history-legend'>\n$1\n</div>", 'histlegend' );
 500                 $s = Html::openElement( 'form', [ 'action' => wfScript(),
 501                         'id' => 'mw-history-compare' ] ) . "\n";
 502                 $s .= Html::hidden( 'title', $this->getTitle()->getPrefixedDBkey() ) . "\n";
 503                 $s .= Html::hidden( 'action', 'historysubmit' ) . "\n";
 504                 $s .= Html::hidden( 'type', 'revision' ) . "\n";
 505
 506                 // Button container stored in $this->buttons for re-use in getEndBody()
 507                 $this->buttons = '<div>';
 508                 $className = 'historysubmit mw-history-compareselectedversions-button';
 509                 $attrs = [ 'class' => $className ]
 510                         + Linker::tooltipAndAccesskeyAttribs( 'compareselectedversions' );
 511                 $this->buttons .= $this->submitButton( $this->msg( 'compareselectedversions' )->text(),
 512                         $attrs
 513                 ) . "\n";
 514
 515                 $user = $this->getUser();
 516                 $actionButtons = '';
 517                 if ( $user->isAllowed( 'deleterevision' ) ) {
 518                         $actionButtons .= $this->getRevisionButton( 'revisiondelete', 'showhideselectedversions' );
 519                 }
 520                 if ( $this->showTagEditUI ) {
 521                         $actionButtons .= $this->getRevisionButton( 'editchangetags', 'history-edit-tags' );
 522                 }
 523                 if ( $actionButtons ) {
 524                         $this->buttons .= Xml::tags( 'div', [ 'class' =>
 525                                 'mw-history-revisionactions' ], $actionButtons );
 526                 }
 527
 528                 if ( $user->isAllowed( 'deleterevision' ) || $this->showTagEditUI ) {
 529                         $this->buttons .= ( new ListToggle( $this->getOutput() ) )->getHTML();
 530                 }
 531
 532                 $this->buttons .= '</div>';
 533
 534                 $s .= $this->buttons;
 535                 $s .= '<ul id="pagehistory">' . "\n";
 536
 537                 return $s;
 538         }
 539
 540         private function getRevisionButton( $name, $msg ) {
 541                 $this->preventClickjacking();
 542                 # Note bug #20966, <button> is non-standard in IE<8
 543                 $element = Html::element(
 544                         'button',
 545                         [
 546                                 'type' => 'submit',
 547                                 'name' => $name,
 548                                 'value' => '1',
 549                                 'class' => "historysubmit mw-history-$name-button",
 550                         ],
 551                         $this->msg( $msg )->text()
 552                 ) . "\n";
 553                 return $element;
 554         }
 555
 556         function getEndBody() {
 557                 if ( $this->lastRow ) {
 558                         $latest = $this->counter == 1 && $this->mIsFirst;
 559                         $firstInList = $this->counter == 1;
 560                         if ( $this->mIsBackwards ) {
 561                                 # Next row is unknown, but for UI reasons, probably exists if an offset has been specified
 562                                 if ( $this->mOffset == '' ) {
 563                                         $next = null;
 564                                 } else {
 565                                         $next = 'unknown';
 566                                 }
 567                         } else {
 568                                 # The next row is the past-the-end row
 569                                 $next = $this->mPastTheEndRow;
 570                         }
 571                         $this->counter++;
 572
 573                         $notifTimestamp = $this->getConfig()->get( 'ShowUpdatedMarker' )
 574                                 ? $this->getTitle()->getNotificationTimestamp( $this->getUser() )
 575                                 : false;
 576
 577                         $s = $this->historyLine(
 578                                 $this->lastRow, $next, $notifTimestamp, $latest, $firstInList );
 579                 } else {
 580                         $s = '';
 581                 }
 582                 $s .= "</ul>\n";
 583                 # Add second buttons only if there is more than one rev
 584                 if ( $this->getNumRows() > 2 ) {
 585                         $s .= $this->buttons;
 586                 }
 587                 $s .= '</form>';
 588
 589                 return $s;
 590         }
 591
 592         /**
 593          * Creates a submit button
 594          *
 595          * @param string $message Text of the submit button, will be escaped
 596          * @param array $attributes Attributes
 597          * @return string HTML output for the submit button
 598          */
 599         function submitButton( $message, $attributes = [] ) {
 600                 # Disable submit button if history has 1 revision only
 601                 if ( $this->getNumRows() > 1 ) {
 602                         return Html::submitButton( $message, $attributes );
 603                 } else {
 604                         return '';
 605                 }
 606         }
 607
 608         /**
 609          * Returns a row from the history printout.
 610          *
 611          * @todo document some more, and maybe clean up the code (some params redundant?)
 612          *
 613          * @param stdClass $row The database row corresponding to the previous line.
 614          * @param mixed $next The database row corresponding to the next line
 615          *   (chronologically previous)
 616          * @param bool|string $notificationtimestamp
 617          * @param bool $latest Whether this row corresponds to the page's latest revision.
 618          * @param bool $firstInList Whether this row corresponds to the first
 619          *   displayed on this history page.
 620          * @return string HTML output for the row
 621          */
 622         function historyLine( $row, $next, $notificationtimestamp = false,
 623                 $latest = false, $firstInList = false ) {
 624                 $rev = new Revision( $row );
 625                 $rev->setTitle( $this->getTitle() );
 626
 627                 if ( is_object( $next ) ) {
 628                         $prevRev = new Revision( $next );
 629                         $prevRev->setTitle( $this->getTitle() );
 630                 } else {
 631                         $prevRev = null;
 632                 }
 633
 634                 $curlink = $this->curLink( $rev, $latest );
 635                 $lastlink = $this->lastLink( $rev, $next );
 636                 $curLastlinks = $curlink . $this->historyPage->message['pipe-separator'] . $lastlink;
 637                 $histLinks = Html::rawElement(
 638                         'span',
 639                         [ 'class' => 'mw-history-histlinks' ],
 640                         $this->msg( 'parentheses' )->rawParams( $curLastlinks )->escaped()
 641                 );
 642
 643                 $diffButtons = $this->diffButtons( $rev, $firstInList );
 644                 $s = $histLinks . $diffButtons;
 645
 646                 $link = $this->revLink( $rev );
 647                 $classes = [];
 648
 649                 $del = '';
 650                 $user = $this->getUser();
 651                 $canRevDelete = $user->isAllowed( 'deleterevision' );
 652                 // Show checkboxes for each revision, to allow for revision deletion and
 653                 // change tags
 654                 if ( $canRevDelete || $this->showTagEditUI ) {
 655                         $this->preventClickjacking();
 656                         // If revision was hidden from sysops and we don't need the checkbox
 657                         // for anything else, disable it
 658                         if ( !$this->showTagEditUI && !$rev->userCan( Revision::DELETED_RESTRICTED, $user ) ) {
 659                                 $del = Xml::check( 'deleterevisions', false, [ 'disabled' => 'disabled' ] );
 660                         // Otherwise, enable the checkbox...
 661                         } else {
 662                                 $del = Xml::check( 'showhiderevisions', false,
 663                                         [ 'name' => 'ids[' . $rev->getId() . ']' ] );
 664                         }
 665                 // User can only view deleted revisions...
 666                 } elseif ( $rev->getVisibility() && $user->isAllowed( 'deletedhistory' ) ) {
 667                         // If revision was hidden from sysops, disable the link
 668                         if ( !$rev->userCan( Revision::DELETED_RESTRICTED, $user ) ) {
 669                                 $del = Linker::revDeleteLinkDisabled( false );
 670                         // Otherwise, show the link...
 671                         } else {
 672                                 $query = [ 'type' => 'revision',
 673                                         'target' => $this->getTitle()->getPrefixedDBkey(), 'ids' => $rev->getId() ];
 674                                 $del .= Linker::revDeleteLink( $query,
 675                                         $rev->isDeleted( Revision::DELETED_RESTRICTED ), false );
 676                         }
 677                 }
 678                 if ( $del ) {
 679                         $s .= " $del ";
 680                 }
 681
 682                 $lang = $this->getLanguage();
 683                 $dirmark = $lang->getDirMark();
 684
 685                 $s .= " $link";
 686                 $s .= $dirmark;
 687                 $s .= " <span class='history-user'>" .
 688                         Linker::revUserTools( $rev, true ) . "</span>";
 689                 $s .= $dirmark;
 690
 691                 if ( $rev->isMinor() ) {
 692                         $s .= ' ' . ChangesList::flag( 'minor', $this->getContext() );
 693                 }
 694
 695                 # Sometimes rev_len isn't populated
 696                 if ( $rev->getSize() !== null ) {
 697                         # Size is always public data
 698                         $prevSize = isset( $this->parentLens[$row->rev_parent_id] )
 699                                 ? $this->parentLens[$row->rev_parent_id]
 700                                 : 0;
 701                         $sDiff = ChangesList::showCharacterDifference( $prevSize, $rev->getSize() );
 702                         $fSize = Linker::formatRevisionSize( $rev->getSize() );
 703                         $s .= ' <span class="mw-changeslist-separator">. .</span> ' . "$fSize $sDiff";
 704                 }
 705
 706                 # Text following the character difference is added just before running hooks
 707                 $s2 = Linker::revComment( $rev, false, true );
 708
 709                 if ( $notificationtimestamp && ( $row->rev_timestamp >= $notificationtimestamp ) ) {
 710                         $s2 .= ' <span class="updatedmarker">' . $this->msg( 'updatedmarker' )->escaped() . '</span>';
 711                         $classes[] = 'mw-history-line-updated';
 712                 }
 713
 714                 $tools = [];
 715
 716                 # Rollback and undo links
 717                 if ( $prevRev && $this->getTitle()->quickUserCan( 'edit', $user ) ) {
 718                         if ( $latest && $this->getTitle()->quickUserCan( 'rollback', $user ) ) {
 719                                 // Get a rollback link without the brackets
 720                                 $rollbackLink = Linker::generateRollback(
 721                                         $rev,
 722                                         $this->getContext(),
 723                                         [ 'verify', 'noBrackets' ]
 724                                 );
 725                                 if ( $rollbackLink ) {
 726                                         $this->preventClickjacking();
 727                                         $tools[] = $rollbackLink;
 728                                 }
 729                         }
 730
 731                         if ( !$rev->isDeleted( Revision::DELETED_TEXT )
 732                                 && !$prevRev->isDeleted( Revision::DELETED_TEXT )
 733                         ) {
 734                                 # Create undo tooltip for the first (=latest) line only
 735                                 $undoTooltip = $latest
 736                                         ? [ 'title' => $this->msg( 'tooltip-undo' )->text() ]
 737                                         : [];
 738                                 $undolink = Linker::linkKnown(
 739                                         $this->getTitle(),
 740                                         $this->msg( 'editundo' )->escaped(),
 741                                         $undoTooltip,
 742                                         [
 743                                                 'action' => 'edit',
 744                                                 'undoafter' => $prevRev->getId(),
 745                                                 'undo' => $rev->getId()
 746                                         ]
 747                                 );
 748                                 $tools[] = "<span class=\"mw-history-undo\">{$undolink}</span>";
 749                         }
 750                 }
 751                 // Allow extension to add their own links here
 752                 Hooks::run( 'HistoryRevisionTools', [ $rev, &$tools, $prevRev, $user ] );
 753
 754                 if ( $tools ) {
 755                         $s2 .= ' ' . $this->msg( 'parentheses' )->rawParams( $lang->pipeList( $tools ) )->escaped();
 756                 }
 757
 758                 # Tags
 759                 list( $tagSummary, $newClasses ) = ChangeTags::formatSummaryRow(
 760                         $row->ts_tags,
 761                         'history',
 762                         $this->getContext()
 763                 );
 764                 $classes = array_merge( $classes, $newClasses );
 765                 if ( $tagSummary !== '' ) {
 766                         $s2 .= " $tagSummary";
 767                 }
 768
 769                 # Include separator between character difference and following text
 770                 if ( $s2 !== '' ) {
 771                         $s .= ' <span class="mw-changeslist-separator">. .</span> ' . $s2;
 772                 }
 773
 774                 Hooks::run( 'PageHistoryLineEnding', [ $this, &$row, &$s, &$classes ] );
 775
 776                 $attribs = [];
 777                 if ( $classes ) {
 778                         $attribs['class'] = implode( ' ', $classes );
 779                 }
 780
 781                 return Xml::tags( 'li', $attribs, $s ) . "\n";
 782         }
 783
 784         /**
 785          * Create a link to view this revision of the page
 786          *
 787          * @param Revision $rev
 788          * @return string
 789          */
 790         function revLink( $rev ) {
 791                 $date = $this->getLanguage()->userTimeAndDate( $rev->getTimestamp(), $this->getUser() );
 792                 $date = htmlspecialchars( $date );
 793                 if ( $rev->userCan( Revision::DELETED_TEXT, $this->getUser() ) ) {
 794                         $link = Linker::linkKnown(
 795                                 $this->getTitle(),
 796                                 $date,
 797                                 [ 'class' => 'mw-changeslist-date' ],
 798                                 [ 'oldid' => $rev->getId() ]
 799                         );
 800                 } else {
 801                         $link = $date;
 802                 }
 803                 if ( $rev->isDeleted( Revision::DELETED_TEXT ) ) {
 804                         $link = "<span class=\"history-deleted\">$link</span>";
 805                 }
 806
 807                 return $link;
 808         }
 809
 810         /**
 811          * Create a diff-to-current link for this revision for this page
 812          *
 813          * @param Revision $rev
 814          * @param bool $latest This is the latest revision of the page?
 815          * @return string
 816          */
 817         function curLink( $rev, $latest ) {
 818                 $cur = $this->historyPage->message['cur'];
 819                 if ( $latest || !$rev->userCan( Revision::DELETED_TEXT, $this->getUser() ) ) {
 820                         return $cur;
 821                 } else {
 822                         return Linker::linkKnown(
 823                                 $this->getTitle(),
 824                                 $cur,
 825                                 [],
 826                                 [
 827                                         'diff' => $this->getWikiPage()->getLatest(),
 828                                         'oldid' => $rev->getId()
 829                                 ]
 830                         );
 831                 }
 832         }
 833
 834         /**
 835          * Create a diff-to-previous link for this revision for this page.
 836          *
 837          * @param Revision $prevRev The revision being displayed
 838          * @param stdClass|string|null $next The next revision in list (that is
 839          *        the previous one in chronological order).
 840          *        May either be a row, "unknown" or null.
 841          * @return string
 842          */
 843         function lastLink( $prevRev, $next ) {
 844                 $last = $this->historyPage->message['last'];
 845
 846                 if ( $next === null ) {
 847                         # Probably no next row
 848                         return $last;
 849                 }
 850
 851                 if ( $next === 'unknown' ) {
 852                         # Next row probably exists but is unknown, use an oldid=prev link
 853                         return Linker::linkKnown(
 854                                 $this->getTitle(),
 855                                 $last,
 856                                 [],
 857                                 [
 858                                         'diff' => $prevRev->getId(),
 859                                         'oldid' => 'prev'
 860                                 ]
 861                         );
 862                 }
 863
 864                 $nextRev = new Revision( $next );
 865
 866                 if ( !$prevRev->userCan( Revision::DELETED_TEXT, $this->getUser() )
 867                         || !$nextRev->userCan( Revision::DELETED_TEXT, $this->getUser() )
 868                 ) {
 869                         return $last;
 870                 }
 871
 872                 return Linker::linkKnown(
 873                         $this->getTitle(),
 874                         $last,
 875                         [],
 876                         [
 877                                 'diff' => $prevRev->getId(),
 878                                 'oldid' => $next->rev_id
 879                         ]
 880                 );
 881         }
 882
 883         /**
 884          * Create radio buttons for page history
 885          *
 886          * @param Revision $rev
 887          * @param bool $firstInList Is this version the first one?
 888          *
 889          * @return string HTML output for the radio buttons
 890          */
 891         function diffButtons( $rev, $firstInList ) {
 892                 if ( $this->getNumRows() > 1 ) {
 893                         $id = $rev->getId();
 894                         $radio = [ 'type' => 'radio', 'value' => $id ];
 895                         /** @todo Move title texts to javascript */
 896                         if ( $firstInList ) {
 897                                 $first = Xml::element( 'input',
 898                                         array_merge( $radio, [
 899                                                 'style' => 'visibility:hidden',
 900                                                 'name' => 'oldid',
 901                                                 'id' => 'mw-oldid-null' ] )
 902                                 );
 903                                 $checkmark = [ 'checked' => 'checked' ];
 904                         } else {
 905                                 # Check visibility of old revisions
 906                                 if ( !$rev->userCan( Revision::DELETED_TEXT, $this->getUser() ) ) {
 907                                         $radio['disabled'] = 'disabled';
 908                                         $checkmark = []; // We will check the next possible one
 909                                 } elseif ( !$this->oldIdChecked ) {
 910                                         $checkmark = [ 'checked' => 'checked' ];
 911                                         $this->oldIdChecked = $id;
 912                                 } else {
 913                                         $checkmark = [];
 914                                 }
 915                                 $first = Xml::element( 'input',
 916                                         array_merge( $radio, $checkmark, [
 917                                                 'name' => 'oldid',
 918                                                 'id' => "mw-oldid-$id" ] ) );
 919                                 $checkmark = [];
 920                         }
 921                         $second = Xml::element( 'input',
 922                                 array_merge( $radio, $checkmark, [
 923                                         'name' => 'diff',
 924                                         'id' => "mw-diff-$id" ] ) );
 925
 926                         return $first . $second;
 927                 } else {
 928                         return '';
 929                 }
 930         }
 931
 932         /**
 933          * This is called if a write operation is possible from the generated HTML
 934          * @param bool $enable
 935          */
 936         function preventClickjacking( $enable = true ) {
 937                 $this->preventClickjacking = $enable;
 938         }
 939
 940         /**
 941          * Get the "prevent clickjacking" flag
 942          * @return bool
 943          */
 944         function getPreventClickjacking() {
 945                 return $this->preventClickjacking;
 946         }
 947
 948 }