includes/HistoryPage.php

   1 <?php
   2 /**
   3  * Page history
   4  *
   5  * Split off from Article.php and Skin.php, 2003-12-22
   6  * @file
   7  */
   8
   9 /**
  10  * This class handles printing the history page for an article.  In order to
  11  * be efficient, it uses timestamps rather than offsets for paging, to avoid
  12  * costly LIMIT,offset queries.
  13  *
  14  * Construct it by passing in an Article, and call $h->history() to print the
  15  * history.
  16  *
  17  */
  18 class HistoryPage {
  19         const DIR_PREV = 0;
  20         const DIR_NEXT = 1;
  21
  22         var $article, $title, $skin;
  23
  24         /**
  25          * Construct a new HistoryPage.
  26          *
  27          * @param $article Article
  28          */
  29         function __construct( $article ) {
  30                 global $wgUser;
  31                 $this->article = $article;
  32                 $this->title = $article->getTitle();
  33                 $this->skin = $wgUser->getSkin();
  34                 $this->preCacheMessages();
  35         }
  36
  37         function getArticle() {
  38                 return $this->article;
  39         }
  40
  41         function getTitle() {
  42                 return $this->title;
  43         }
  44
  45         /**
  46          * As we use the same small set of messages in various methods and that
  47          * they are called often, we call them once and save them in $this->message
  48          */
  49         function preCacheMessages() {
  50                 // Precache various messages
  51                 if( !isset( $this->message ) ) {
  52                         $msgs = array( 'cur', 'last', 'pipe-separator' );
  53                         foreach( $msgs as $msg ) {
  54                                 $this->message[$msg] = wfMsgExt( $msg, array( 'escapenoentities') );
  55                         }
  56                 }
  57         }
  58
  59         /**
  60          * Print the history page for an article.
  61          * @return nothing
  62          */
  63         function history() {
  64                 global $wgOut, $wgRequest, $wgScript;
  65
  66                 /*
  67                  * Allow client caching.
  68                  */
  69                 if( $wgOut->checkLastModified( $this->article->getTouched() ) )
  70                         return; // Client cache fresh and headers sent, nothing more to do.
  71
  72                 wfProfileIn( __METHOD__ );
  73
  74                 /*
  75                  * Setup page variables.
  76                  */
  77                 $wgOut->setPageTitle( wfMsg( 'history-title', $this->title->getPrefixedText() ) );
  78                 $wgOut->setPageTitleActionText( wfMsg( 'history_short' ) );
  79                 $wgOut->setArticleFlag( false );
  80                 $wgOut->setArticleRelated( true );
  81                 $wgOut->setRobotPolicy( 'noindex,nofollow' );
  82                 $wgOut->setSyndicated( true );
  83                 $wgOut->setFeedAppendQuery( 'action=history' );
  84                 $wgOut->addScriptFile( 'history.js' );
  85
  86                 $logPage = SpecialPage::getTitleFor( 'Log' );
  87                 $logLink = $this->skin->link(
  88                         $logPage,
  89                         wfMsgHtml( 'viewpagelogs' ),
  90                         array(),
  91                         array( 'page' => $this->title->getPrefixedText() ),
  92                         array( 'known', 'noclasses' )
  93                 );
  94                 $wgOut->setSubtitle( $logLink );
  95
  96                 $feedType = $wgRequest->getVal( 'feed' );
  97                 if( $feedType ) {
  98                         wfProfileOut( __METHOD__ );
  99                         return $this->feed( $feedType );
 100                 }
 101
 102                 /*
 103                  * Fail if article doesn't exist.
 104                  */
 105                 if( !$this->title->exists() ) {
 106                         $wgOut->addWikiMsg( 'nohistory' );
 107                         # show deletion/move log if there is an entry
 108                         LogEventsList::showLogExtract(
 109                                 $wgOut,
 110                                 array( 'delete', 'move' ),
 111                                 $this->title->getPrefixedText(),
 112                                 '',
 113                                 array(  'lim' => 10,
 114                                         'conds' => array( "log_action != 'revision'" ),
 115                                         'showIfEmpty' => false,
 116                                         'msgKey' => array( 'moveddeleted-notice' )
 117                                 )
 118                         );
 119                         wfProfileOut( __METHOD__ );
 120                         return;
 121                 }
 122
 123                 /**
 124                  * Add date selector to quickly get to a certain time
 125                  */
 126                 $year = $wgRequest->getInt( 'year' );
 127                 $month = $wgRequest->getInt( 'month' );
 128                 $tagFilter = $wgRequest->getVal( 'tagfilter' );
 129                 $tagSelector = ChangeTags::buildTagFilterSelector( $tagFilter );
 130                 /**
 131                  * Option to show only revisions that have been (partially) hidden via RevisionDelete
 132                  */
 133                 if ( $wgRequest->getBool( 'deleted' ) ) {
 134                         $conds = array("rev_deleted != '0'");
 135                 } else {
 136                         $conds = array();
 137                 }
 138                 $checkDeleted = Xml::checkLabel( wfMsg( 'history-show-deleted' ),
 139                         'deleted', 'mw-show-deleted-only', $wgRequest->getBool( 'deleted' ) ) . "\n";
 140
 141                 $action = htmlspecialchars( $wgScript );
 142                 $wgOut->addHTML(
 143                         "<form action=\"$action\" method=\"get\" id=\"mw-history-searchform\">" .
 144                         Xml::fieldset(
 145                                 wfMsg( 'history-fieldset-title' ),
 146                                 false,
 147                                 array( 'id' => 'mw-history-search' )
 148                         ) .
 149                         Xml::hidden( 'title', $this->title->getPrefixedDBKey() ) . "\n" .
 150                         Xml::hidden( 'action', 'history' ) . "\n" .
 151                         Xml::dateMenu( $year, $month ) . '&nbsp;' .
 152                         ( $tagSelector ? ( implode( '&nbsp;', $tagSelector ) . '&nbsp;' ) : '' ) .
 153                         $checkDeleted .
 154                         Xml::submitButton( wfMsg( 'allpagessubmit' ) ) . "\n" .
 155                         '</fieldset></form>'
 156                 );
 157
 158                 wfRunHooks( 'PageHistoryBeforeList', array( &$this->article ) );
 159
 160                 /**
 161                  * Do the list
 162                  */
 163                 $pager = new HistoryPager( $this, $year, $month, $tagFilter, $conds );
 164                 $wgOut->addHTML(
 165                         $pager->getNavigationBar() .
 166                         $pager->getBody() .
 167                         $pager->getNavigationBar()
 168                 );
 169                 $wgOut->preventClickjacking( $pager->getPreventClickjacking() );
 170
 171                 wfProfileOut( __METHOD__ );
 172         }
 173
 174         /**
 175          * Fetch an array of revisions, specified by a given limit, offset and
 176          * direction. This is now only used by the feeds. It was previously
 177          * used by the main UI but that's now handled by the pager.
 178          *
 179          * @param $limit Integer: the limit number of revisions to get
 180          * @param $offset Integer
 181          * @param $direction Integer: either HistoryPage::DIR_PREV or HistoryPage::DIR_NEXT
 182          * @return ResultWrapper
 183          */
 184         function fetchRevisions( $limit, $offset, $direction ) {
 185                 $dbr = wfGetDB( DB_SLAVE );
 186
 187                 if( $direction == HistoryPage::DIR_PREV )
 188                         list($dirs, $oper) = array("ASC", ">=");
 189                 else /* $direction == HistoryPage::DIR_NEXT */
 190                         list($dirs, $oper) = array("DESC", "<=");
 191
 192                 if( $offset )
 193                         $offsets = array("rev_timestamp $oper '$offset'");
 194                 else
 195                         $offsets = array();
 196
 197                 $page_id = $this->title->getArticleID();
 198
 199                 return $dbr->select( 'revision',
 200                         Revision::selectFields(),
 201                         array_merge(array("rev_page=$page_id"), $offsets),
 202                         __METHOD__,
 203                         array( 'ORDER BY' => "rev_timestamp $dirs",
 204                                 'USE INDEX' => 'page_timestamp', 'LIMIT' => $limit)
 205                 );
 206         }
 207
 208         /**
 209          * Output a subscription feed listing recent edits to this page.
 210          *
 211          * @param $type String: feed type
 212          */
 213         function feed( $type ) {
 214                 global $wgFeedClasses, $wgRequest, $wgFeedLimit;
 215                 if( !FeedUtils::checkFeedOutput($type) ) {
 216                         return;
 217                 }
 218
 219                 $feed = new $wgFeedClasses[$type](
 220                         $this->title->getPrefixedText() . ' - ' .
 221                         wfMsgForContent( 'history-feed-title' ),
 222                         wfMsgForContent( 'history-feed-description' ),
 223                         $this->title->getFullUrl( 'action=history' )
 224                 );
 225
 226                 // Get a limit on number of feed entries. Provide a sane default
 227                 // of 10 if none is defined (but limit to $wgFeedLimit max)
 228                 $limit = $wgRequest->getInt( 'limit', 10 );
 229                 if( $limit > $wgFeedLimit || $limit < 1 ) {
 230                         $limit = 10;
 231                 }
 232                 $items = $this->fetchRevisions($limit, 0, HistoryPage::DIR_NEXT);
 233
 234                 $feed->outHeader();
 235                 if( $items ) {
 236                         foreach( $items as $row ) {
 237                                 $feed->outItem( $this->feedItem( $row ) );
 238                         }
 239                 } else {
 240                         $feed->outItem( $this->feedEmpty() );
 241                 }
 242                 $feed->outFooter();
 243         }
 244
 245         function feedEmpty() {
 246                 global $wgOut;
 247                 return new FeedItem(
 248                         wfMsgForContent( 'nohistory' ),
 249                         $wgOut->parse( wfMsgForContent( 'history-feed-empty' ) ),
 250                         $this->title->getFullUrl(),
 251                         wfTimestamp( TS_MW ),
 252                         '',
 253                         $this->title->getTalkPage()->getFullUrl()
 254                 );
 255         }
 256
 257         /**
 258          * Generate a FeedItem object from a given revision table row
 259          * Borrows Recent Changes' feed generation functions for formatting;
 260          * includes a diff to the previous revision (if any).
 261          *
 262          * @param $row Object: database row
 263          * @return FeedItem
 264          */
 265         function feedItem( $row ) {
 266                 $rev = new Revision( $row );
 267                 $rev->setTitle( $this->title );
 268                 $text = FeedUtils::formatDiffRow(
 269                         $this->title,
 270                         $this->title->getPreviousRevisionID( $rev->getId() ),
 271                         $rev->getId(),
 272                         $rev->getTimestamp(),
 273                         $rev->getComment()
 274                 );
 275                 if( $rev->getComment() == '' ) {
 276                         global $wgContLang;
 277                         $title = wfMsgForContent( 'history-feed-item-nocomment',
 278                                 $rev->getUserText(),
 279                                 $wgContLang->timeanddate( $rev->getTimestamp() ),
 280                                 $wgContLang->date( $rev->getTimestamp() ),
 281                                 $wgContLang->time( $rev->getTimestamp() )
 282                         );
 283                 } else {
 284                         $title = $rev->getUserText() .
 285                         wfMsgForContent( 'colon-separator' ) .
 286                         FeedItem::stripComment( $rev->getComment() );
 287                 }
 288                 return new FeedItem(
 289                         $title,
 290                         $text,
 291                         $this->title->getFullUrl( 'diff=' . $rev->getId() . '&oldid=prev' ),
 292                         $rev->getTimestamp(),
 293                         $rev->getUserText(),
 294                         $this->title->getTalkPage()->getFullUrl()
 295                 );
 296         }
 297 }
 298
 299 /**
 300  * @ingroup Pager
 301  */
 302 class HistoryPager extends ReverseChronologicalPager {
 303         public $lastRow = false, $counter, $historyPage, $title, $buttons, $conds;
 304         protected $oldIdChecked;
 305         protected $preventClickjacking = false;
 306
 307         function __construct( $historyPage, $year='', $month='', $tagFilter = '', $conds = array() ) {
 308                 parent::__construct();
 309                 $this->historyPage = $historyPage;
 310                 $this->title = $this->historyPage->title;
 311                 $this->tagFilter = $tagFilter;
 312                 $this->getDateCond( $year, $month );
 313                 $this->conds = $conds;
 314         }
 315
 316         // For hook compatibility...
 317         function getArticle() {
 318                 return $this->historyPage->getArticle();
 319         }
 320
 321         function getSqlComment() {
 322                 if ( $this->conds ) {
 323                         return 'history page filtered'; // potentially slow, see CR r58153
 324                 } else {
 325                         return 'history page unfiltered';
 326                 }
 327         }
 328
 329         function getQueryInfo() {
 330                 $queryInfo = array(
 331                         'tables'  => array('revision'),
 332                         'fields'  => Revision::selectFields(),
 333                         'conds'   => array_merge(
 334                                 array( 'rev_page' => $this->historyPage->title->getArticleID() ),
 335                                 $this->conds ),
 336                         'options' => array( 'USE INDEX' => array('revision' => 'page_timestamp') ),
 337                         'join_conds' => array( 'tag_summary' => array( 'LEFT JOIN', 'ts_rev_id=rev_id' ) ),
 338                 );
 339                 ChangeTags::modifyDisplayQuery(
 340                         $queryInfo['tables'],
 341                         $queryInfo['fields'],
 342                         $queryInfo['conds'],
 343                         $queryInfo['join_conds'],
 344                         $queryInfo['options'],
 345                         $this->tagFilter
 346                 );
 347                 wfRunHooks( 'PageHistoryPager::getQueryInfo', array( &$this, &$queryInfo ) );
 348                 return $queryInfo;
 349         }
 350
 351         function getIndexField() {
 352                 return 'rev_timestamp';
 353         }
 354
 355         function formatRow( $row ) {
 356                 if( $this->lastRow ) {
 357                         $latest = ($this->counter == 1 && $this->mIsFirst);
 358                         $firstInList = $this->counter == 1;
 359                         $s = $this->historyLine( $this->lastRow, $row, $this->counter++,
 360                                 $this->title->getNotificationTimestamp(), $latest, $firstInList );
 361                 } else {
 362                         $s = '';
 363                 }
 364                 $this->lastRow = $row;
 365                 return $s;
 366         }
 367
 368         /**
 369          * Creates begin of history list with a submit button
 370          *
 371          * @return string HTML output
 372          */
 373         function getStartBody() {
 374                 global $wgScript, $wgUser, $wgOut, $wgContLang;
 375                 $this->lastRow = false;
 376                 $this->counter = 1;
 377                 $this->oldIdChecked = 0;
 378
 379                 $wgOut->wrapWikiMsg( "<div class='mw-history-legend'>\n$1</div>", 'histlegend' );
 380                 $s = Xml::openElement( 'form', array( 'action' => $wgScript,
 381                         'id' => 'mw-history-compare' ) ) . "\n";
 382                 $s .= Xml::hidden( 'title', $this->title->getPrefixedDbKey() ) . "\n";
 383                 $s .= Xml::hidden( 'action', 'historysubmit' ) . "\n";
 384
 385                 $this->buttons = '<div>';
 386                 if( $wgUser->isAllowed('deleterevision') ) {
 387                         $this->preventClickjacking();
 388                         $float = $wgContLang->alignEnd();
 389                         # Note bug #20966, <button> is non-standard in IE<8
 390                         $this->buttons .= Xml::element( 'button',
 391                                 array(
 392                                         'type' => 'submit',
 393                                         'name' => 'revisiondelete',
 394                                         'value' => '1',
 395                                         'style' => "float: $float;",
 396                                         'class' => 'mw-history-revisiondelete-button',
 397                                 ),
 398                                 wfMsg( 'showhideselectedversions' )
 399                         ) . "\n";
 400                 }
 401                 $this->buttons .= $this->submitButton( wfMsg( 'compareselectedversions'),
 402                         array(
 403                                 'class'     => 'historysubmit',
 404                                 'accesskey' => wfMsg( 'accesskey-compareselectedversions' ),
 405                                 'title'     => wfMsg( 'tooltip-compareselectedversions' ),
 406                         )
 407                 ) . "\n";
 408                 $this->buttons .= '</div>';
 409                 $s .= $this->buttons . '<ul id="pagehistory">' . "\n";
 410                 return $s;
 411         }
 412
 413         function getEndBody() {
 414                 if( $this->lastRow ) {
 415                         $latest = $this->counter == 1 && $this->mIsFirst;
 416                         $firstInList = $this->counter == 1;
 417                         if( $this->mIsBackwards ) {
 418                                 # Next row is unknown, but for UI reasons, probably exists if an offset has been specified
 419                                 if( $this->mOffset == '' ) {
 420                                         $next = null;
 421                                 } else {
 422                                         $next = 'unknown';
 423                                 }
 424                         } else {
 425                                 # The next row is the past-the-end row
 426                                 $next = $this->mPastTheEndRow;
 427                         }
 428                         $s = $this->historyLine( $this->lastRow, $next, $this->counter++,
 429                                 $this->title->getNotificationTimestamp(), $latest, $firstInList );
 430                 } else {
 431                         $s = '';
 432                 }
 433                 $s .= "</ul>\n";
 434                 # Add second buttons only if there is more than one rev
 435                 if( $this->getNumRows() > 2 ) {
 436                         $s .= $this->buttons;
 437                 }
 438                 $s .= '</form>';
 439                 return $s;
 440         }
 441
 442         /**
 443          * Creates a submit button
 444          *
 445          * @param $message String: text of the submit button, will be escaped
 446          * @param $attributes Array: attributes
 447          * @return String: HTML output for the submit button
 448          */
 449         function submitButton( $message, $attributes = array() ) {
 450                 # Disable submit button if history has 1 revision only
 451                 if( $this->getNumRows() > 1 ) {
 452                         return Xml::submitButton( $message , $attributes );
 453                 } else {
 454                         return '';
 455                 }
 456         }
 457
 458         /**
 459          * Returns a row from the history printout.
 460          *
 461          * @todo document some more, and maybe clean up the code (some params redundant?)
 462          *
 463          * @param $row Object: the database row corresponding to the previous line.
 464          * @param $next Mixed: the database row corresponding to the next line.
 465          * @param $counter Integer: apparently a counter of what row number we're at, counted from the top row = 1.
 466          * @param $notificationtimestamp
 467          * @param $latest Boolean: whether this row corresponds to the page's latest revision.
 468          * @param $firstInList Boolean: whether this row corresponds to the first displayed on this history page.
 469          * @return String: HTML output for the row
 470          */
 471         function historyLine( $row, $next, $counter = '', $notificationtimestamp = false,
 472                 $latest = false, $firstInList = false )
 473         {
 474                 global $wgUser, $wgLang;
 475                 $rev = new Revision( $row );
 476                 $rev->setTitle( $this->title );
 477
 478                 $curlink = $this->curLink( $rev, $latest );
 479                 $lastlink = $this->lastLink( $rev, $next, $counter );
 480                 $diffButtons = $this->diffButtons( $rev, $firstInList, $counter );
 481                 $histLinks = Html::rawElement(
 482                                 'span',
 483                                 array( 'class' => 'mw-history-histlinks' ),
 484                                 '(' . $curlink . $this->historyPage->message['pipe-separator'] . $lastlink . ') '
 485                 );
 486                 $s = $histLinks . $diffButtons;
 487
 488                 $link = $this->revLink( $rev );
 489                 $classes = array();
 490
 491                 $del = '';
 492                 // User can delete revisions...
 493                 if( $wgUser->isAllowed( 'deleterevision' ) ) {
 494                         $this->preventClickjacking();
 495                         // If revision was hidden from sysops, disable the checkbox
 496                         if( !$rev->userCan( Revision::DELETED_RESTRICTED ) ) {
 497                                 $del = Xml::check( 'deleterevisions', false, array( 'disabled' => 'disabled' ) );
 498                         // Otherwise, enable the checkbox...
 499                         } else {
 500                                 $del = Xml::check( 'showhiderevisions', false,
 501                                         array( 'name' => 'ids['.$rev->getId().']' ) );
 502                         }
 503                 // User can only view deleted revisions...
 504                 } else if( $rev->getVisibility() && $wgUser->isAllowed( 'deletedhistory' ) ) {
 505                         // If revision was hidden from sysops, disable the link
 506                         if( !$rev->userCan( Revision::DELETED_RESTRICTED ) ) {
 507                                 $cdel = $this->getSkin()->revDeleteLinkDisabled( false );
 508                         // Otherwise, show the link...
 509                         } else {
 510                                 $query = array( 'type' => 'revision',
 511                                         'target' => $this->title->getPrefixedDbkey(), 'ids' => $rev->getId() );
 512                                 $del .= $this->getSkin()->revDeleteLink( $query,
 513                                         $rev->isDeleted( Revision::DELETED_RESTRICTED ), false );
 514                         }
 515                 }
 516                 if( $del ) $s .= " $del ";
 517
 518                 $s .= " $link";
 519                 $s .= " <span class='history-user'>" .
 520                         $this->getSkin()->revUserTools( $rev, true ) . "</span>";
 521
 522                 if( $rev->isMinor() ) {
 523                         $s .= ' ' . ChangesList::flag( 'minor' );
 524                 }
 525
 526                 if( !is_null( $size = $rev->getSize() ) && !$rev->isDeleted( Revision::DELETED_TEXT ) ) {
 527                         $s .= ' ' . $this->getSkin()->formatRevisionSize( $size );
 528                 }
 529
 530                 $s .= $this->getSkin()->revComment( $rev, false, true );
 531
 532                 if( $notificationtimestamp && ($row->rev_timestamp >= $notificationtimestamp) ) {
 533                         $s .= ' <span class="updatedmarker">' .  wfMsgHtml( 'updatedmarker' ) . '</span>';
 534                 }
 535
 536                 $tools = array();
 537
 538                 # Rollback and undo links
 539                 if( !is_null( $next ) && is_object( $next ) ) {
 540                         if( $latest && $this->title->userCan( 'rollback' ) && $this->title->userCan( 'edit' ) ) {
 541                                 $this->preventClickjacking();
 542                                 $tools[] = '<span class="mw-rollback-link">'.
 543                                         $this->getSkin()->buildRollbackLink( $rev ).'</span>';
 544                         }
 545
 546                         if( $this->title->quickUserCan( 'edit' )
 547                                 && !$rev->isDeleted( Revision::DELETED_TEXT )
 548                                 && !$next->rev_deleted & Revision::DELETED_TEXT )
 549                         {
 550                                 # Create undo tooltip for the first (=latest) line only
 551                                 $undoTooltip = $latest
 552                                         ? array( 'title' => wfMsg( 'tooltip-undo' ) )
 553                                         : array();
 554                                 $undolink = $this->getSkin()->link(
 555                                         $this->title,
 556                                         wfMsgHtml( 'editundo' ),
 557                                         $undoTooltip,
 558                                         array(
 559                                                 'action' => 'edit',
 560                                                 'undoafter' => $next->rev_id,
 561                                                 'undo' => $rev->getId()
 562                                         ),
 563                                         array( 'known', 'noclasses' )
 564                                 );
 565                                 $tools[] = "<span class=\"mw-history-undo\">{$undolink}</span>";
 566                         }
 567                 }
 568
 569                 if( $tools ) {
 570                         $s .= ' (' . $wgLang->pipeList( $tools ) . ')';
 571                 }
 572
 573                 # Tags
 574                 list($tagSummary, $newClasses) = ChangeTags::formatSummaryRow( $row->ts_tags, 'history' );
 575                 $classes = array_merge( $classes, $newClasses );
 576                 $s .= " $tagSummary";
 577
 578                 wfRunHooks( 'PageHistoryLineEnding', array( $this, &$row , &$s, &$classes ) );
 579
 580                 $attribs = array();
 581                 if ( $classes ) {
 582                         $attribs['class'] = implode( ' ', $classes );
 583                 }
 584
 585                 return Xml::tags( 'li', $attribs, $s ) . "\n";
 586         }
 587
 588         /**
 589          * Create a link to view this revision of the page
 590          *
 591          * @param $rev Revision
 592          * @return String
 593          */
 594         function revLink( $rev ) {
 595                 global $wgLang;
 596                 $date = $wgLang->timeanddate( wfTimestamp(TS_MW, $rev->getTimestamp()), true );
 597                 $date = htmlspecialchars( $date );
 598                 if( !$rev->isDeleted( Revision::DELETED_TEXT ) ) {
 599                         $link = $this->getSkin()->link(
 600                                 $this->title,
 601                                 $date,
 602                                 array(),
 603                                 array( 'oldid' => $rev->getId() ),
 604                                 array( 'known', 'noclasses' )
 605                         );
 606                 } else {
 607                         $link = "<span class=\"history-deleted\">$date</span>";
 608                 }
 609                 return $link;
 610         }
 611
 612         /**
 613          * Create a diff-to-current link for this revision for this page
 614          *
 615          * @param $rev Revision
 616          * @param $latest Boolean: this is the latest revision of the page?
 617          * @return String
 618          */
 619         function curLink( $rev, $latest ) {
 620                 $cur = $this->historyPage->message['cur'];
 621                 if( $latest || !$rev->userCan( Revision::DELETED_TEXT ) ) {
 622                         return $cur;
 623                 } else {
 624                         return $this->getSkin()->link(
 625                                 $this->title,
 626                                 $cur,
 627                                 array(),
 628                                 array(
 629                                         'diff' => $this->title->getLatestRevID(),
 630                                         'oldid' => $rev->getId()
 631                                 ),
 632                                 array( 'known', 'noclasses' )
 633                         );
 634                 }
 635         }
 636
 637         /**
 638          * Create a diff-to-previous link for this revision for this page.
 639          *
 640          * @param $prevRev Revision: the previous revision
 641          * @param $next Mixed: the newer revision
 642          * @param $counter Integer: what row on the history list this is
 643          * @return String
 644          */
 645         function lastLink( $prevRev, $next, $counter ) {
 646                 $last = $this->historyPage->message['last'];
 647                 # $next may either be a Row, null, or "unkown"
 648                 $nextRev = is_object($next) ? new Revision( $next ) : $next;
 649                 if( is_null($next) ) {
 650                         # Probably no next row
 651                         return $last;
 652                 } elseif( $next === 'unknown' ) {
 653                         # Next row probably exists but is unknown, use an oldid=prev link
 654                         return $this->getSkin()->link(
 655                                 $this->title,
 656                                 $last,
 657                                 array(),
 658                                 array(
 659                                         'diff' => $prevRev->getId(),
 660                                         'oldid' => 'prev'
 661                                 ),
 662                                 array( 'known', 'noclasses' )
 663                         );
 664                 } elseif( !$prevRev->userCan(Revision::DELETED_TEXT)
 665                         || !$nextRev->userCan(Revision::DELETED_TEXT) )
 666                 {
 667                         return $last;
 668                 } else {
 669                         return $this->getSkin()->link(
 670                                 $this->title,
 671                                 $last,
 672                                 array(),
 673                                 array(
 674                                         'diff' => $prevRev->getId(),
 675                                         'oldid' => $next->rev_id
 676                                 ),
 677                                 array( 'known', 'noclasses' )
 678                         );
 679                 }
 680         }
 681
 682         /**
 683          * Create radio buttons for page history
 684          *
 685          * @param $rev Revision object
 686          * @param $firstInList Boolean: is this version the first one?
 687          * @param $counter Integer: a counter of what row number we're at, counted from the top row = 1.
 688          * @return String: HTML output for the radio buttons
 689          */
 690         function diffButtons( $rev, $firstInList, $counter ) {
 691                 if( $this->getNumRows() > 1 ) {
 692                         $id = $rev->getId();
 693                         $radio = array( 'type'  => 'radio', 'value' => $id );
 694                         /** @todo: move title texts to javascript */
 695                         if( $firstInList ) {
 696                                 $first = Xml::element( 'input',
 697                                         array_merge( $radio, array(
 698                                                 'style' => 'visibility:hidden',
 699                                                 'name'  => 'oldid',
 700                                                 'id' => 'mw-oldid-null' ) )
 701                                 );
 702                                 $checkmark = array( 'checked' => 'checked' );
 703                         } else {
 704                                 # Check visibility of old revisions
 705                                 if( !$rev->userCan( Revision::DELETED_TEXT ) ) {
 706                                         $radio['disabled'] = 'disabled';
 707                                         $checkmark = array(); // We will check the next possible one
 708                                 } else if( $counter == 2 || !$this->oldIdChecked ) {
 709                                         $checkmark = array( 'checked' => 'checked' );
 710                                         $this->oldIdChecked = $id;
 711                                 } else {
 712                                         $checkmark = array();
 713                                 }
 714                                 $first = Xml::element( 'input',
 715                                         array_merge( $radio, $checkmark, array(
 716                                                 'name'  => 'oldid',
 717                                                 'id' => "mw-oldid-$id" ) ) );
 718                                 $checkmark = array();
 719                         }
 720                         $second = Xml::element( 'input',
 721                                 array_merge( $radio, $checkmark, array(
 722                                         'name'  => 'diff',
 723                                         'id' => "mw-diff-$id" ) ) );
 724                         return $first . $second;
 725                 } else {
 726                         return '';
 727                 }
 728         }
 729
 730         /**
 731          * This is called if a write operation is possible from the generated HTML
 732          */
 733         function preventClickjacking( $enable = true ) {
 734                 $this->preventClickjacking = $enable;
 735         }
 736
 737         /**
 738          * Get the "prevent clickjacking" flag
 739          */
 740         function getPreventClickjacking() {
 741                 return $this->preventClickjacking;
 742         }
 743 }
 744
 745 /**
 746  * Backwards-compatibility aliases
 747  */
 748 class PageHistory extends HistoryPage {}
 749 class PageHistoryPager extends HistoryPager {}