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 use MediaWiki\MediaWikiServices;
  27 use Wikimedia\Rdbms\ResultWrapper;
  28 use Wikimedia\Rdbms\FakeResultWrapper;
  29
  30 /**
  31  * This class handles printing the history page for an article. In order to
  32  * be efficient, it uses timestamps rather than offsets for paging, to avoid
  33  * costly LIMIT,offset queries.
  34  *
  35  * Construct it by passing in an Article, and call $h->history() to print the
  36  * history.
  37  *
  38  * @ingroup Actions
  39  */
  40 class HistoryAction extends FormlessAction {
  41         const DIR_PREV = 0;
  42         const DIR_NEXT = 1;
  43
  44         /** @var array Array of message keys and strings */
  45         public $message;
  46
  47         public function getName() {
  48                 return 'history';
  49         }
  50
  51         public function requiresWrite() {
  52                 return false;
  53         }
  54
  55         public function requiresUnblock() {
  56                 return false;
  57         }
  58
  59         protected function getPageTitle() {
  60                 return $this->msg( 'history-title', $this->getTitle()->getPrefixedText() )->text();
  61         }
  62
  63         protected function getDescription() {
  64                 // Creation of a subtitle link pointing to [[Special:Log]]
  65                 $linkRenderer = MediaWikiServices::getInstance()->getLinkRenderer();
  66                 $subtitle = $linkRenderer->makeKnownLink(
  67                         SpecialPage::getTitleFor( 'Log' ),
  68                         $this->msg( 'viewpagelogs' )->text(),
  69                         [],
  70                         [ 'page' => $this->getTitle()->getPrefixedText() ]
  71                 );
  72
  73                 $links = [];
  74                 // Allow extensions to add more links
  75                 Hooks::run( 'HistoryPageToolLinks', [ $this->getContext(), $linkRenderer, &$links ] );
  76                 if ( $links ) {
  77                         $subtitle .= ''
  78                                 . $this->msg( 'word-separator' )->escaped()
  79                                 . $this->msg( 'parentheses' )
  80                                         ->rawParams( $this->getLanguage()->pipeList( $links ) )
  81                                         ->escaped();
  82                 }
  83                 return $subtitle;
  84         }
  85
  86         /**
  87          * @return WikiPage|Article|ImagePage|CategoryPage|Page The Article object we are working on.
  88          */
  89         public function getArticle() {
  90                 return $this->page;
  91         }
  92
  93         /**
  94          * As we use the same small set of messages in various methods and that
  95          * they are called often, we call them once and save them in $this->message
  96          */
  97         private function preCacheMessages() {
  98                 // Precache various messages
  99                 if ( !isset( $this->message ) ) {
 100                         $msgs = [ 'cur', 'last', 'pipe-separator' ];
 101                         foreach ( $msgs as $msg ) {
 102                                 $this->message[$msg] = $this->msg( $msg )->escaped();
 103                         }
 104                 }
 105         }
 106
 107         /**
 108          * Print the history page for an article.
 109          */
 110         function onView() {
 111                 $out = $this->getOutput();
 112                 $request = $this->getRequest();
 113
 114                 /**
 115                  * Allow client caching.
 116                  */
 117                 if ( $out->checkLastModified( $this->page->getTouched() ) ) {
 118                         return; // Client cache fresh and headers sent, nothing more to do.
 119                 }
 120
 121                 $this->preCacheMessages();
 122                 $config = $this->context->getConfig();
 123
 124                 # Fill in the file cache if not set already
 125                 if ( HTMLFileCache::useFileCache( $this->getContext() ) ) {
 126                         $cache = new HTMLFileCache( $this->getTitle(), 'history' );
 127                         if ( !$cache->isCacheGood( /* Assume up to date */ ) ) {
 128                                 ob_start( [ &$cache, 'saveToFileCache' ] );
 129                         }
 130                 }
 131
 132                 // Setup page variables.
 133                 $out->setFeedAppendQuery( 'action=history' );
 134                 $out->addModules( 'mediawiki.action.history' );
 135                 $out->addModuleStyles( [
 136                         'mediawiki.action.history.styles',
 137                         'mediawiki.special.changeslist',
 138                 ] );
 139                 if ( $config->get( 'UseMediaWikiUIEverywhere' ) ) {
 140                         $out = $this->getOutput();
 141                         $out->addModuleStyles( [
 142                                 'mediawiki.ui.input',
 143                                 'mediawiki.ui.checkbox',
 144                         ] );
 145                 }
 146
 147                 // Handle atom/RSS feeds.
 148                 $feedType = $request->getVal( 'feed' );
 149                 if ( $feedType ) {
 150                         $this->feed( $feedType );
 151
 152                         return;
 153                 }
 154
 155                 $this->addHelpLink( '//meta.wikimedia.org/wiki/Special:MyLanguage/Help:Page_history', true );
 156
 157                 // Fail nicely if article doesn't exist.
 158                 if ( !$this->page->exists() ) {
 159                         global $wgSend404Code;
 160                         if ( $wgSend404Code ) {
 161                                 $out->setStatusCode( 404 );
 162                         }
 163                         $out->addWikiMsg( 'nohistory' );
 164
 165                         $dbr = wfGetDB( DB_REPLICA );
 166
 167                         # show deletion/move log if there is an entry
 168                         LogEventsList::showLogExtract(
 169                                 $out,
 170                                 [ 'delete', 'move', 'protect' ],
 171                                 $this->getTitle(),
 172                                 '',
 173                                 [ 'lim' => 10,
 174                                         'conds' => [ 'log_action != ' . $dbr->addQuotes( 'revision' ) ],
 175                                         'showIfEmpty' => false,
 176                                         'msgKey' => [ 'moveddeleted-notice' ]
 177                                 ]
 178                         );
 179
 180                         return;
 181                 }
 182
 183                 /**
 184                  * Add date selector to quickly get to a certain time
 185                  */
 186                 $year = $request->getInt( 'year' );
 187                 $month = $request->getInt( 'month' );
 188                 $tagFilter = $request->getVal( 'tagfilter' );
 189                 $tagSelector = ChangeTags::buildTagFilterSelector( $tagFilter, false, $this->getContext() );
 190
 191                 /**
 192                  * Option to show only revisions that have been (partially) hidden via RevisionDelete
 193                  */
 194                 if ( $request->getBool( 'deleted' ) ) {
 195                         $conds = [ 'rev_deleted != 0' ];
 196                 } else {
 197                         $conds = [];
 198                 }
 199                 if ( $this->getUser()->isAllowed( 'deletedhistory' ) ) {
 200                         $checkDeleted = Xml::checkLabel( $this->msg( 'history-show-deleted' )->text(),
 201                                 'deleted', 'mw-show-deleted-only', $request->getBool( 'deleted' ) ) . "\n";
 202                 } else {
 203                         $checkDeleted = '';
 204                 }
 205
 206                 // Add the general form
 207                 $action = htmlspecialchars( wfScript() );
 208                 $content = Html::hidden( 'title', $this->getTitle()->getPrefixedDBkey() ) . "\n";
 209                 $content .= Html::hidden( 'action', 'history' ) . "\n";
 210                 $content .= Xml::dateMenu(
 211                         ( $year == null ? MWTimestamp::getLocalInstance()->format( 'Y' ) : $year ),
 212                         $month
 213                 ) . "\u{00A0}";
 214                 $content .= $tagSelector ? ( implode( "\u{00A0}", $tagSelector ) . "\u{00A0}" ) : '';
 215                 $content .= $checkDeleted . Html::submitButton(
 216                         $this->msg( 'historyaction-submit' )->text(),
 217                         [],
 218                         [ 'mw-ui-progressive' ]
 219                 );
 220                 $out->addHTML(
 221                         "<form action=\"$action\" method=\"get\" id=\"mw-history-searchform\">" .
 222                         Xml::fieldset(
 223                                 $this->msg( 'history-fieldset-title' )->text(),
 224                                 $content,
 225                                 [ 'id' => 'mw-history-search' ]
 226                         ) .
 227                         '</form>'
 228                 );
 229
 230                 Hooks::run( 'PageHistoryBeforeList', [ &$this->page, $this->getContext() ] );
 231
 232                 // Create and output the list.
 233                 $pager = new HistoryPager( $this, $year, $month, $tagFilter, $conds );
 234                 $out->addHTML(
 235                         $pager->getNavigationBar() .
 236                         $pager->getBody() .
 237                         $pager->getNavigationBar()
 238                 );
 239                 $out->preventClickjacking( $pager->getPreventClickjacking() );
 240         }
 241
 242         /**
 243          * Fetch an array of revisions, specified by a given limit, offset and
 244          * direction. This is now only used by the feeds. It was previously
 245          * used by the main UI but that's now handled by the pager.
 246          *
 247          * @param int $limit The limit number of revisions to get
 248          * @param int $offset
 249          * @param int $direction Either self::DIR_PREV or self::DIR_NEXT
 250          * @return ResultWrapper
 251          */
 252         function fetchRevisions( $limit, $offset, $direction ) {
 253                 // Fail if article doesn't exist.
 254                 if ( !$this->getTitle()->exists() ) {
 255                         return new FakeResultWrapper( [] );
 256                 }
 257
 258                 $dbr = wfGetDB( DB_REPLICA );
 259
 260                 if ( $direction === self::DIR_PREV ) {
 261                         list( $dirs, $oper ) = [ "ASC", ">=" ];
 262                 } else { /* $direction === self::DIR_NEXT */
 263                         list( $dirs, $oper ) = [ "DESC", "<=" ];
 264                 }
 265
 266                 if ( $offset ) {
 267                         $offsets = [ "rev_timestamp $oper " . $dbr->addQuotes( $dbr->timestamp( $offset ) ) ];
 268                 } else {
 269                         $offsets = [];
 270                 }
 271
 272                 $page_id = $this->page->getId();
 273
 274                 $revQuery = Revision::getQueryInfo();
 275                 return $dbr->select(
 276                         $revQuery['tables'],
 277                         $revQuery['fields'],
 278                         array_merge( [ 'rev_page' => $page_id ], $offsets ),
 279                         __METHOD__,
 280                         [
 281                                 'ORDER BY' => "rev_timestamp $dirs",
 282                                 'USE INDEX' => [ 'revision' => 'page_timestamp' ],
 283                                 'LIMIT' => $limit
 284                         ],
 285                         $revQuery['joins']
 286                 );
 287         }
 288
 289         /**
 290          * Output a subscription feed listing recent edits to this page.
 291          *
 292          * @param string $type Feed type
 293          */
 294         function feed( $type ) {
 295                 if ( !FeedUtils::checkFeedOutput( $type ) ) {
 296                         return;
 297                 }
 298                 $request = $this->getRequest();
 299
 300                 $feedClasses = $this->context->getConfig()->get( 'FeedClasses' );
 301                 /** @var RSSFeed|AtomFeed $feed */
 302                 $feed = new $feedClasses[$type](
 303                         $this->getTitle()->getPrefixedText() . ' - ' .
 304                         $this->msg( 'history-feed-title' )->inContentLanguage()->text(),
 305                         $this->msg( 'history-feed-description' )->inContentLanguage()->text(),
 306                         $this->getTitle()->getFullURL( 'action=history' )
 307                 );
 308
 309                 // Get a limit on number of feed entries. Provide a sane default
 310                 // of 10 if none is defined (but limit to $wgFeedLimit max)
 311                 $limit = $request->getInt( 'limit', 10 );
 312                 $limit = min(
 313                         max( $limit, 1 ),
 314                         $this->context->getConfig()->get( 'FeedLimit' )
 315                 );
 316
 317                 $items = $this->fetchRevisions( $limit, 0, self::DIR_NEXT );
 318
 319                 // Generate feed elements enclosed between header and footer.
 320                 $feed->outHeader();
 321                 if ( $items->numRows() ) {
 322                         foreach ( $items as $row ) {
 323                                 $feed->outItem( $this->feedItem( $row ) );
 324                         }
 325                 } else {
 326                         $feed->outItem( $this->feedEmpty() );
 327                 }
 328                 $feed->outFooter();
 329         }
 330
 331         function feedEmpty() {
 332                 return new FeedItem(
 333                         $this->msg( 'nohistory' )->inContentLanguage()->text(),
 334                         $this->msg( 'history-feed-empty' )->inContentLanguage()->parseAsBlock(),
 335                         $this->getTitle()->getFullURL(),
 336                         wfTimestamp( TS_MW ),
 337                         '',
 338                         $this->getTitle()->getTalkPage()->getFullURL()
 339                 );
 340         }
 341
 342         /**
 343          * Generate a FeedItem object from a given revision table row
 344          * Borrows Recent Changes' feed generation functions for formatting;
 345          * includes a diff to the previous revision (if any).
 346          *
 347          * @param stdClass|array $row Database row
 348          * @return FeedItem
 349          */
 350         function feedItem( $row ) {
 351                 $rev = new Revision( $row, 0, $this->getTitle() );
 352
 353                 $text = FeedUtils::formatDiffRow(
 354                         $this->getTitle(),
 355                         $this->getTitle()->getPreviousRevisionID( $rev->getId() ),
 356                         $rev->getId(),
 357                         $rev->getTimestamp(),
 358                         $rev->getComment()
 359                 );
 360                 if ( $rev->getComment() == '' ) {
 361                         $contLang = MediaWikiServices::getInstance()->getContentLanguage();
 362                         $title = $this->msg( 'history-feed-item-nocomment',
 363                                 $rev->getUserText(),
 364                                 $contLang->timeanddate( $rev->getTimestamp() ),
 365                                 $contLang->date( $rev->getTimestamp() ),
 366                                 $contLang->time( $rev->getTimestamp() )
 367                         )->inContentLanguage()->text();
 368                 } else {
 369                         $title = $rev->getUserText() .
 370                                 $this->msg( 'colon-separator' )->inContentLanguage()->text() .
 371                                 FeedItem::stripComment( $rev->getComment() );
 372                 }
 373
 374                 return new FeedItem(
 375                         $title,
 376                         $text,
 377                         $this->getTitle()->getFullURL( 'diff=' . $rev->getId() . '&oldid=prev' ),
 378                         $rev->getTimestamp(),
 379                         $rev->getUserText(),
 380                         $this->getTitle()->getTalkPage()->getFullURL()
 381                 );
 382         }
 383 }
 384
 385 /**
 386  * @ingroup Pager
 387  * @ingroup Actions
 388  */
 389 class HistoryPager extends ReverseChronologicalPager {
 390         /**
 391          * @var bool|stdClass
 392          */
 393         public $lastRow = false;
 394
 395         public $counter, $historyPage, $buttons, $conds;
 396
 397         protected $oldIdChecked;
 398
 399         protected $preventClickjacking = false;
 400         /**
 401          * @var array
 402          */
 403         protected $parentLens;
 404
 405         /** @var bool Whether to show the tag editing UI */
 406         protected $showTagEditUI;
 407
 408         /** @var string */
 409         private $tagFilter;
 410
 411         /**
 412          * @param HistoryAction $historyPage
 413          * @param string $year
 414          * @param string $month
 415          * @param string $tagFilter
 416          * @param array $conds
 417          */
 418         public function __construct(
 419                 HistoryAction $historyPage,
 420                 $year = '',
 421                 $month = '',
 422                 $tagFilter = '',
 423                 array $conds = []
 424         ) {
 425                 parent::__construct( $historyPage->getContext() );
 426                 $this->historyPage = $historyPage;
 427                 $this->tagFilter = $tagFilter;
 428                 $this->getDateCond( $year, $month );
 429                 $this->conds = $conds;
 430                 $this->showTagEditUI = ChangeTags::showTagEditingUI( $this->getUser() );
 431         }
 432
 433         // For hook compatibility...
 434         function getArticle() {
 435                 return $this->historyPage->getArticle();
 436         }
 437
 438         function getSqlComment() {
 439                 if ( $this->conds ) {
 440                         return 'history page filtered'; // potentially slow, see CR r58153
 441                 } else {
 442                         return 'history page unfiltered';
 443                 }
 444         }
 445
 446         function getQueryInfo() {
 447                 $revQuery = Revision::getQueryInfo( [ 'user' ] );
 448                 $queryInfo = [
 449                         'tables' => $revQuery['tables'],
 450                         'fields' => $revQuery['fields'],
 451                         'conds' => array_merge(
 452                                 [ 'rev_page' => $this->getWikiPage()->getId() ],
 453                                 $this->conds ),
 454                         'options' => [ 'USE INDEX' => [ 'revision' => 'page_timestamp' ] ],
 455                         'join_conds' => $revQuery['joins'],
 456                 ];
 457                 ChangeTags::modifyDisplayQuery(
 458                         $queryInfo['tables'],
 459                         $queryInfo['fields'],
 460                         $queryInfo['conds'],
 461                         $queryInfo['join_conds'],
 462                         $queryInfo['options'],
 463                         $this->tagFilter
 464                 );
 465
 466                 // Avoid PHP 7.1 warning of passing $this by reference
 467                 $historyPager = $this;
 468                 Hooks::run( 'PageHistoryPager::getQueryInfo', [ &$historyPager, &$queryInfo ] );
 469
 470                 return $queryInfo;
 471         }
 472
 473         function getIndexField() {
 474                 return 'rev_timestamp';
 475         }
 476
 477         /**
 478          * @param stdClass $row
 479          * @return string
 480          */
 481         function formatRow( $row ) {
 482                 if ( $this->lastRow ) {
 483                         $latest = ( $this->counter == 1 && $this->mIsFirst );
 484                         $firstInList = $this->counter == 1;
 485                         $this->counter++;
 486
 487                         $notifTimestamp = $this->getConfig()->get( 'ShowUpdatedMarker' )
 488                                 ? $this->getTitle()->getNotificationTimestamp( $this->getUser() )
 489                                 : false;
 490
 491                         $s = $this->historyLine(
 492                                 $this->lastRow, $row, $notifTimestamp, $latest, $firstInList );
 493                 } else {
 494                         $s = '';
 495                 }
 496                 $this->lastRow = $row;
 497
 498                 return $s;
 499         }
 500
 501         function doBatchLookups() {
 502                 if ( !Hooks::run( 'PageHistoryPager::doBatchLookups', [ $this, $this->mResult ] ) ) {
 503                         return;
 504                 }
 505
 506                 # Do a link batch query
 507                 $this->mResult->seek( 0 );
 508                 $batch = new LinkBatch();
 509                 $revIds = [];
 510                 foreach ( $this->mResult as $row ) {
 511                         if ( $row->rev_parent_id ) {
 512                                 $revIds[] = $row->rev_parent_id;
 513                         }
 514                         if ( !is_null( $row->user_name ) ) {
 515                                 $batch->add( NS_USER, $row->user_name );
 516                                 $batch->add( NS_USER_TALK, $row->user_name );
 517                         } else { # for anons or usernames of imported revisions
 518                                 $batch->add( NS_USER, $row->rev_user_text );
 519                                 $batch->add( NS_USER_TALK, $row->rev_user_text );
 520                         }
 521                 }
 522                 $this->parentLens = Revision::getParentLengths( $this->mDb, $revIds );
 523                 $batch->execute();
 524                 $this->mResult->seek( 0 );
 525         }
 526
 527         /**
 528          * Creates begin of history list with a submit button
 529          *
 530          * @return string HTML output
 531          */
 532         function getStartBody() {
 533                 $this->lastRow = false;
 534                 $this->counter = 1;
 535                 $this->oldIdChecked = 0;
 536
 537                 $this->getOutput()->wrapWikiMsg( "<div class='mw-history-legend'>\n$1\n</div>", 'histlegend' );
 538                 $s = Html::openElement( 'form', [ 'action' => wfScript(),
 539                         'id' => 'mw-history-compare' ] ) . "\n";
 540                 $s .= Html::hidden( 'title', $this->getTitle()->getPrefixedDBkey() ) . "\n";
 541                 $s .= Html::hidden( 'action', 'historysubmit' ) . "\n";
 542                 $s .= Html::hidden( 'type', 'revision' ) . "\n";
 543
 544                 // Button container stored in $this->buttons for re-use in getEndBody()
 545                 $this->buttons = '<div>';
 546                 $className = 'historysubmit mw-history-compareselectedversions-button';
 547                 $attrs = [ 'class' => $className ]
 548                         + Linker::tooltipAndAccesskeyAttribs( 'compareselectedversions' );
 549                 $this->buttons .= $this->submitButton( $this->msg( 'compareselectedversions' )->text(),
 550                         $attrs
 551                 ) . "\n";
 552
 553                 $user = $this->getUser();
 554                 $actionButtons = '';
 555                 if ( $user->isAllowed( 'deleterevision' ) ) {
 556                         $actionButtons .= $this->getRevisionButton( 'revisiondelete', 'showhideselectedversions' );
 557                 }
 558                 if ( $this->showTagEditUI ) {
 559                         $actionButtons .= $this->getRevisionButton( 'editchangetags', 'history-edit-tags' );
 560                 }
 561                 if ( $actionButtons ) {
 562                         $this->buttons .= Xml::tags( 'div', [ 'class' =>
 563                                 'mw-history-revisionactions' ], $actionButtons );
 564                 }
 565
 566                 if ( $user->isAllowed( 'deleterevision' ) || $this->showTagEditUI ) {
 567                         $this->buttons .= ( new ListToggle( $this->getOutput() ) )->getHTML();
 568                 }
 569
 570                 $this->buttons .= '</div>';
 571
 572                 $s .= $this->buttons;
 573                 $s .= '<ul id="pagehistory">' . "\n";
 574
 575                 return $s;
 576         }
 577
 578         private function getRevisionButton( $name, $msg ) {
 579                 $this->preventClickjacking();
 580                 # Note T22966, <button> is non-standard in IE<8
 581                 $element = Html::element(
 582                         'button',
 583                         [
 584                                 'type' => 'submit',
 585                                 'name' => $name,
 586                                 'value' => '1',
 587                                 'class' => "historysubmit mw-history-$name-button",
 588                         ],
 589                         $this->msg( $msg )->text()
 590                 ) . "\n";
 591                 return $element;
 592         }
 593
 594         function getEndBody() {
 595                 if ( $this->lastRow ) {
 596                         $latest = $this->counter == 1 && $this->mIsFirst;
 597                         $firstInList = $this->counter == 1;
 598                         if ( $this->mIsBackwards ) {
 599                                 # Next row is unknown, but for UI reasons, probably exists if an offset has been specified
 600                                 if ( $this->mOffset == '' ) {
 601                                         $next = null;
 602                                 } else {
 603                                         $next = 'unknown';
 604                                 }
 605                         } else {
 606                                 # The next row is the past-the-end row
 607                                 $next = $this->mPastTheEndRow;
 608                         }
 609                         $this->counter++;
 610
 611                         $notifTimestamp = $this->getConfig()->get( 'ShowUpdatedMarker' )
 612                                 ? $this->getTitle()->getNotificationTimestamp( $this->getUser() )
 613                                 : false;
 614
 615                         $s = $this->historyLine(
 616                                 $this->lastRow, $next, $notifTimestamp, $latest, $firstInList );
 617                 } else {
 618                         $s = '';
 619                 }
 620                 $s .= "</ul>\n";
 621                 # Add second buttons only if there is more than one rev
 622                 if ( $this->getNumRows() > 2 ) {
 623                         $s .= $this->buttons;
 624                 }
 625                 $s .= '</form>';
 626
 627                 return $s;
 628         }
 629
 630         /**
 631          * Creates a submit button
 632          *
 633          * @param string $message Text of the submit button, will be escaped
 634          * @param array $attributes
 635          * @return string HTML output for the submit button
 636          */
 637         function submitButton( $message, $attributes = [] ) {
 638                 # Disable submit button if history has 1 revision only
 639                 if ( $this->getNumRows() > 1 ) {
 640                         return Html::submitButton( $message, $attributes );
 641                 } else {
 642                         return '';
 643                 }
 644         }
 645
 646         /**
 647          * Returns a row from the history printout.
 648          *
 649          * @todo document some more, and maybe clean up the code (some params redundant?)
 650          *
 651          * @param stdClass $row The database row corresponding to the previous line.
 652          * @param mixed $next The database row corresponding to the next line
 653          *   (chronologically previous)
 654          * @param bool|string $notificationtimestamp
 655          * @param bool $latest Whether this row corresponds to the page's latest revision.
 656          * @param bool $firstInList Whether this row corresponds to the first
 657          *   displayed on this history page.
 658          * @return string HTML output for the row
 659          */
 660         function historyLine( $row, $next, $notificationtimestamp = false,
 661                 $latest = false, $firstInList = false ) {
 662                 $rev = new Revision( $row, 0, $this->getTitle() );
 663
 664                 if ( is_object( $next ) ) {
 665                         $prevRev = new Revision( $next, 0, $this->getTitle() );
 666                 } else {
 667                         $prevRev = null;
 668                 }
 669
 670                 $curlink = $this->curLink( $rev, $latest );
 671                 $lastlink = $this->lastLink( $rev, $next );
 672                 $curLastlinks = $curlink . $this->historyPage->message['pipe-separator'] . $lastlink;
 673                 $histLinks = Html::rawElement(
 674                         'span',
 675                         [ 'class' => 'mw-history-histlinks' ],
 676                         $this->msg( 'parentheses' )->rawParams( $curLastlinks )->escaped()
 677                 );
 678
 679                 $diffButtons = $this->diffButtons( $rev, $firstInList );
 680                 $s = $histLinks . $diffButtons;
 681
 682                 $link = $this->revLink( $rev );
 683                 $classes = [];
 684
 685                 $del = '';
 686                 $user = $this->getUser();
 687                 $canRevDelete = $user->isAllowed( 'deleterevision' );
 688                 // Show checkboxes for each revision, to allow for revision deletion and
 689                 // change tags
 690                 if ( $canRevDelete || $this->showTagEditUI ) {
 691                         $this->preventClickjacking();
 692                         // If revision was hidden from sysops and we don't need the checkbox
 693                         // for anything else, disable it
 694                         if ( !$this->showTagEditUI && !$rev->userCan( Revision::DELETED_RESTRICTED, $user ) ) {
 695                                 $del = Xml::check( 'deleterevisions', false, [ 'disabled' => 'disabled' ] );
 696                         // Otherwise, enable the checkbox...
 697                         } else {
 698                                 $del = Xml::check( 'showhiderevisions', false,
 699                                         [ 'name' => 'ids[' . $rev->getId() . ']' ] );
 700                         }
 701                 // User can only view deleted revisions...
 702                 } elseif ( $rev->getVisibility() && $user->isAllowed( 'deletedhistory' ) ) {
 703                         // If revision was hidden from sysops, disable the link
 704                         if ( !$rev->userCan( Revision::DELETED_RESTRICTED, $user ) ) {
 705                                 $del = Linker::revDeleteLinkDisabled( false );
 706                         // Otherwise, show the link...
 707                         } else {
 708                                 $query = [ 'type' => 'revision',
 709                                         'target' => $this->getTitle()->getPrefixedDBkey(), 'ids' => $rev->getId() ];
 710                                 $del .= Linker::revDeleteLink( $query,
 711                                         $rev->isDeleted( Revision::DELETED_RESTRICTED ), false );
 712                         }
 713                 }
 714                 if ( $del ) {
 715                         $s .= " $del ";
 716                 }
 717
 718                 $lang = $this->getLanguage();
 719                 $dirmark = $lang->getDirMark();
 720
 721                 $s .= " $link";
 722                 $s .= $dirmark;
 723                 $s .= " <span class='history-user'>" .
 724                         Linker::revUserTools( $rev, true ) . "</span>";
 725                 $s .= $dirmark;
 726
 727                 if ( $rev->isMinor() ) {
 728                         $s .= ' ' . ChangesList::flag( 'minor', $this->getContext() );
 729                 }
 730
 731                 # Sometimes rev_len isn't populated
 732                 if ( $rev->getSize() !== null ) {
 733                         # Size is always public data
 734                         $prevSize = $this->parentLens[$row->rev_parent_id] ?? 0;
 735                         $sDiff = ChangesList::showCharacterDifference( $prevSize, $rev->getSize() );
 736                         $fSize = Linker::formatRevisionSize( $rev->getSize() );
 737                         $s .= ' <span class="mw-changeslist-separator">. .</span> ' . "$fSize $sDiff";
 738                 }
 739
 740                 # Text following the character difference is added just before running hooks
 741                 $s2 = Linker::revComment( $rev, false, true );
 742
 743                 if ( $notificationtimestamp && ( $row->rev_timestamp >= $notificationtimestamp ) ) {
 744                         $s2 .= ' <span class="updatedmarker">' . $this->msg( 'updatedmarker' )->escaped() . '</span>';
 745                         $classes[] = 'mw-history-line-updated';
 746                 }
 747
 748                 $tools = [];
 749
 750                 # Rollback and undo links
 751                 if ( $prevRev && $this->getTitle()->quickUserCan( 'edit', $user ) ) {
 752                         if ( $latest && $this->getTitle()->quickUserCan( 'rollback', $user ) ) {
 753                                 // Get a rollback link without the brackets
 754                                 $rollbackLink = Linker::generateRollback(
 755                                         $rev,
 756                                         $this->getContext(),
 757                                         [ 'verify', 'noBrackets' ]
 758                                 );
 759                                 if ( $rollbackLink ) {
 760                                         $this->preventClickjacking();
 761                                         $tools[] = $rollbackLink;
 762                                 }
 763                         }
 764
 765                         if ( !$rev->isDeleted( Revision::DELETED_TEXT )
 766                                 && !$prevRev->isDeleted( Revision::DELETED_TEXT )
 767                         ) {
 768                                 # Create undo tooltip for the first (=latest) line only
 769                                 $undoTooltip = $latest
 770                                         ? [ 'title' => $this->msg( 'tooltip-undo' )->text() ]
 771                                         : [];
 772                                 $undolink = MediaWikiServices::getInstance()->getLinkRenderer()->makeKnownLink(
 773                                         $this->getTitle(),
 774                                         $this->msg( 'editundo' )->text(),
 775                                         $undoTooltip,
 776                                         [
 777                                                 'action' => 'edit',
 778                                                 'undoafter' => $prevRev->getId(),
 779                                                 'undo' => $rev->getId()
 780                                         ]
 781                                 );
 782                                 $tools[] = "<span class=\"mw-history-undo\">{$undolink}</span>";
 783                         }
 784                 }
 785                 // Allow extension to add their own links here
 786                 Hooks::run( 'HistoryRevisionTools', [ $rev, &$tools, $prevRev, $user ] );
 787
 788                 if ( $tools ) {
 789                         $s2 .= ' ' . $this->msg( 'parentheses' )->rawParams( $lang->pipeList( $tools ) )->escaped();
 790                 }
 791
 792                 # Tags
 793                 list( $tagSummary, $newClasses ) = ChangeTags::formatSummaryRow(
 794                         $row->ts_tags,
 795                         'history',
 796                         $this->getContext()
 797                 );
 798                 $classes = array_merge( $classes, $newClasses );
 799                 if ( $tagSummary !== '' ) {
 800                         $s2 .= " $tagSummary";
 801                 }
 802
 803                 # Include separator between character difference and following text
 804                 if ( $s2 !== '' ) {
 805                         $s .= ' <span class="mw-changeslist-separator">. .</span> ' . $s2;
 806                 }
 807
 808                 $attribs = [ 'data-mw-revid' => $rev->getId() ];
 809
 810                 Hooks::run( 'PageHistoryLineEnding', [ $this, &$row, &$s, &$classes, &$attribs ] );
 811                 $attribs = array_filter( $attribs,
 812                         [ Sanitizer::class, 'isReservedDataAttribute' ],
 813                         ARRAY_FILTER_USE_KEY
 814                 );
 815
 816                 if ( $classes ) {
 817                         $attribs['class'] = implode( ' ', $classes );
 818                 }
 819
 820                 return Xml::tags( 'li', $attribs, $s ) . "\n";
 821         }
 822
 823         /**
 824          * Create a link to view this revision of the page
 825          *
 826          * @param Revision $rev
 827          * @return string
 828          */
 829         function revLink( $rev ) {
 830                 $date = $this->getLanguage()->userTimeAndDate( $rev->getTimestamp(), $this->getUser() );
 831                 if ( $rev->userCan( Revision::DELETED_TEXT, $this->getUser() ) ) {
 832                         $link = MediaWikiServices::getInstance()->getLinkRenderer()->makeKnownLink(
 833                                 $this->getTitle(),
 834                                 $date,
 835                                 [ 'class' => 'mw-changeslist-date' ],
 836                                 [ 'oldid' => $rev->getId() ]
 837                         );
 838                 } else {
 839                         $link = htmlspecialchars( $date );
 840                 }
 841                 if ( $rev->isDeleted( Revision::DELETED_TEXT ) ) {
 842                         $link = "<span class=\"history-deleted\">$link</span>";
 843                 }
 844
 845                 return $link;
 846         }
 847
 848         /**
 849          * Create a diff-to-current link for this revision for this page
 850          *
 851          * @param Revision $rev
 852          * @param bool $latest This is the latest revision of the page?
 853          * @return string
 854          */
 855         function curLink( $rev, $latest ) {
 856                 $cur = $this->historyPage->message['cur'];
 857                 if ( $latest || !$rev->userCan( Revision::DELETED_TEXT, $this->getUser() ) ) {
 858                         return $cur;
 859                 } else {
 860                         return MediaWikiServices::getInstance()->getLinkRenderer()->makeKnownLink(
 861                                 $this->getTitle(),
 862                                 new HtmlArmor( $cur ),
 863                                 [],
 864                                 [
 865                                         'diff' => $this->getWikiPage()->getLatest(),
 866                                         'oldid' => $rev->getId()
 867                                 ]
 868                         );
 869                 }
 870         }
 871
 872         /**
 873          * Create a diff-to-previous link for this revision for this page.
 874          *
 875          * @param Revision $prevRev The revision being displayed
 876          * @param stdClass|string|null $next The next revision in list (that is
 877          *        the previous one in chronological order).
 878          *        May either be a row, "unknown" or null.
 879          * @return string
 880          */
 881         function lastLink( $prevRev, $next ) {
 882                 $last = $this->historyPage->message['last'];
 883
 884                 if ( $next === null ) {
 885                         # Probably no next row
 886                         return $last;
 887                 }
 888
 889                 $linkRenderer = MediaWikiServices::getInstance()->getLinkRenderer();
 890                 if ( $next === 'unknown' ) {
 891                         # Next row probably exists but is unknown, use an oldid=prev link
 892                         return $linkRenderer->makeKnownLink(
 893                                 $this->getTitle(),
 894                                 new HtmlArmor( $last ),
 895                                 [],
 896                                 [
 897                                         'diff' => $prevRev->getId(),
 898                                         'oldid' => 'prev'
 899                                 ]
 900                         );
 901                 }
 902
 903                 $nextRev = new Revision( $next );
 904
 905                 if ( !$prevRev->userCan( Revision::DELETED_TEXT, $this->getUser() )
 906                         || !$nextRev->userCan( Revision::DELETED_TEXT, $this->getUser() )
 907                 ) {
 908                         return $last;
 909                 }
 910
 911                 return $linkRenderer->makeKnownLink(
 912                         $this->getTitle(),
 913                         new HtmlArmor( $last ),
 914                         [],
 915                         [
 916                                 'diff' => $prevRev->getId(),
 917                                 'oldid' => $next->rev_id
 918                         ]
 919                 );
 920         }
 921
 922         /**
 923          * Create radio buttons for page history
 924          *
 925          * @param Revision $rev
 926          * @param bool $firstInList Is this version the first one?
 927          *
 928          * @return string HTML output for the radio buttons
 929          */
 930         function diffButtons( $rev, $firstInList ) {
 931                 if ( $this->getNumRows() > 1 ) {
 932                         $id = $rev->getId();
 933                         $radio = [ 'type' => 'radio', 'value' => $id ];
 934                         /** @todo Move title texts to javascript */
 935                         if ( $firstInList ) {
 936                                 $first = Xml::element( 'input',
 937                                         array_merge( $radio, [
 938                                                 'style' => 'visibility:hidden',
 939                                                 'name' => 'oldid',
 940                                                 'id' => 'mw-oldid-null' ] )
 941                                 );
 942                                 $checkmark = [ 'checked' => 'checked' ];
 943                         } else {
 944                                 # Check visibility of old revisions
 945                                 if ( !$rev->userCan( Revision::DELETED_TEXT, $this->getUser() ) ) {
 946                                         $radio['disabled'] = 'disabled';
 947                                         $checkmark = []; // We will check the next possible one
 948                                 } elseif ( !$this->oldIdChecked ) {
 949                                         $checkmark = [ 'checked' => 'checked' ];
 950                                         $this->oldIdChecked = $id;
 951                                 } else {
 952                                         $checkmark = [];
 953                                 }
 954                                 $first = Xml::element( 'input',
 955                                         array_merge( $radio, $checkmark, [
 956                                                 'name' => 'oldid',
 957                                                 'id' => "mw-oldid-$id" ] ) );
 958                                 $checkmark = [];
 959                         }
 960                         $second = Xml::element( 'input',
 961                                 array_merge( $radio, $checkmark, [
 962                                         'name' => 'diff',
 963                                         'id' => "mw-diff-$id" ] ) );
 964
 965                         return $first . $second;
 966                 } else {
 967                         return '';
 968                 }
 969         }
 970
 971         /**
 972          * This is called if a write operation is possible from the generated HTML
 973          * @param bool $enable
 974          */
 975         function preventClickjacking( $enable = true ) {
 976                 $this->preventClickjacking = $enable;
 977         }
 978
 979         /**
 980          * Get the "prevent clickjacking" flag
 981          * @return bool
 982          */
 983         function getPreventClickjacking() {
 984                 return $this->preventClickjacking;
 985         }
 986
 987 }