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                  * Note that this can run a *long* time if there are many revisions to look at.
 133                  * We use "isBigDeletion" to determine if the history is too big to go through.
 134                  * Additionally, only users with 'deleterevision' right can filter for deleted edits.
 135                  */
 136                 if ( $this->title->userCan( 'deleterevision' )
 137                         && ( !$this->article->isBigDeletion() || $this->title->userCan( 'bigdelete' ) ) )
 138                 {
 139                         $conds = ( $wgRequest->getBool( 'deleted' ) )
 140                                 ? array("rev_deleted != '0'")
 141                                 : array();
 142                         $checkDeleted = Xml::checkLabel( wfMsg( 'history-show-deleted' ),
 143                                 'deleted', 'mw-show-deleted-only', $wgRequest->getBool( 'deleted' ) ) . "\n";
 144                 }
 145                 else { # Don't filter and don't add the checkbox for filtering
 146                         $conds = array();
 147                         $checkDeleted = '';
 148                 }
 149
 150                 $action = htmlspecialchars( $wgScript );
 151                 $wgOut->addHTML(
 152                         "<form action=\"$action\" method=\"get\" id=\"mw-history-searchform\">" .
 153                         Xml::fieldset(
 154                                 wfMsg( 'history-fieldset-title' ),
 155                                 false,
 156                                 array( 'id' => 'mw-history-search' )
 157                         ) .
 158                         Xml::hidden( 'title', $this->title->getPrefixedDBKey() ) . "\n" .
 159                         Xml::hidden( 'action', 'history' ) . "\n" .
 160                         Xml::dateMenu( $year, $month ) . '&nbsp;' .
 161                         ( $tagSelector ? ( implode( '&nbsp;', $tagSelector ) . '&nbsp;' ) : '' ) .
 162                         $checkDeleted .
 163                         Xml::submitButton( wfMsg( 'allpagessubmit' ) ) . "\n" .
 164                         '</fieldset></form>'
 165                 );
 166
 167                 wfRunHooks( 'PageHistoryBeforeList', array( &$this->article ) );
 168
 169                 /**
 170                  * Do the list
 171                  */
 172                 $pager = new HistoryPager( $this, $year, $month, $tagFilter, $conds );
 173                 $wgOut->addHTML(
 174                         $pager->getNavigationBar() .
 175                         $pager->getBody() .
 176                         $pager->getNavigationBar()
 177                 );
 178
 179                 wfProfileOut( __METHOD__ );
 180         }
 181
 182         /**
 183          * Fetch an array of revisions, specified by a given limit, offset and
 184          * direction. This is now only used by the feeds. It was previously
 185          * used by the main UI but that's now handled by the pager.
 186          *
 187          * @param $limit Integer: the limit number of revisions to get
 188          * @param $offset Integer
 189          * @param $direction Integer: either HistoryPage::DIR_PREV or HistoryPage::DIR_NEXT
 190          * @return ResultWrapper
 191          */
 192         function fetchRevisions( $limit, $offset, $direction ) {
 193                 $dbr = wfGetDB( DB_SLAVE );
 194
 195                 if( $direction == HistoryPage::DIR_PREV )
 196                         list($dirs, $oper) = array("ASC", ">=");
 197                 else /* $direction == HistoryPage::DIR_NEXT */
 198                         list($dirs, $oper) = array("DESC", "<=");
 199
 200                 if( $offset )
 201                         $offsets = array("rev_timestamp $oper '$offset'");
 202                 else
 203                         $offsets = array();
 204
 205                 $page_id = $this->title->getArticleID();
 206
 207                 return $dbr->select( 'revision',
 208                         Revision::selectFields(),
 209                         array_merge(array("rev_page=$page_id"), $offsets),
 210                         __METHOD__,
 211                         array( 'ORDER BY' => "rev_timestamp $dirs",
 212                                 'USE INDEX' => 'page_timestamp', 'LIMIT' => $limit)
 213                 );
 214         }
 215
 216         /**
 217          * Output a subscription feed listing recent edits to this page.
 218          *
 219          * @param $type String: feed type
 220          */
 221         function feed( $type ) {
 222                 global $wgFeedClasses, $wgRequest, $wgFeedLimit;
 223                 if( !FeedUtils::checkFeedOutput($type) ) {
 224                         return;
 225                 }
 226
 227                 $feed = new $wgFeedClasses[$type](
 228                         $this->title->getPrefixedText() . ' - ' .
 229                         wfMsgForContent( 'history-feed-title' ),
 230                         wfMsgForContent( 'history-feed-description' ),
 231                         $this->title->getFullUrl( 'action=history' )
 232                 );
 233
 234                 // Get a limit on number of feed entries. Provide a sane default
 235                 // of 10 if none is defined (but limit to $wgFeedLimit max)
 236                 $limit = $wgRequest->getInt( 'limit', 10 );
 237                 if( $limit > $wgFeedLimit || $limit < 1 ) {
 238                         $limit = 10;
 239                 }
 240                 $items = $this->fetchRevisions($limit, 0, HistoryPage::DIR_NEXT);
 241
 242                 $feed->outHeader();
 243                 if( $items ) {
 244                         foreach( $items as $row ) {
 245                                 $feed->outItem( $this->feedItem( $row ) );
 246                         }
 247                 } else {
 248                         $feed->outItem( $this->feedEmpty() );
 249                 }
 250                 $feed->outFooter();
 251         }
 252
 253         function feedEmpty() {
 254                 global $wgOut;
 255                 return new FeedItem(
 256                         wfMsgForContent( 'nohistory' ),
 257                         $wgOut->parse( wfMsgForContent( 'history-feed-empty' ) ),
 258                         $this->title->getFullUrl(),
 259                         wfTimestamp( TS_MW ),
 260                         '',
 261                         $this->title->getTalkPage()->getFullUrl()
 262                 );
 263         }
 264
 265         /**
 266          * Generate a FeedItem object from a given revision table row
 267          * Borrows Recent Changes' feed generation functions for formatting;
 268          * includes a diff to the previous revision (if any).
 269          *
 270          * @param $row Object: database row
 271          * @return FeedItem
 272          */
 273         function feedItem( $row ) {
 274                 $rev = new Revision( $row );
 275                 $rev->setTitle( $this->title );
 276                 $text = FeedUtils::formatDiffRow(
 277                         $this->title,
 278                         $this->title->getPreviousRevisionID( $rev->getId() ),
 279                         $rev->getId(),
 280                         $rev->getTimestamp(),
 281                         $rev->getComment()
 282                 );
 283                 if( $rev->getComment() == '' ) {
 284                         global $wgContLang;
 285                         $title = wfMsgForContent( 'history-feed-item-nocomment',
 286                                 $rev->getUserText(),
 287                                 $wgContLang->timeanddate( $rev->getTimestamp() ),
 288                                 $wgContLang->date( $rev->getTimestamp() ),
 289                                 $wgContLang->time( $rev->getTimestamp() )
 290                         );
 291                 } else {
 292                         $title = $rev->getUserText() .
 293                         wfMsgForContent( 'colon-separator' ) .
 294                         FeedItem::stripComment( $rev->getComment() );
 295                 }
 296                 return new FeedItem(
 297                         $title,
 298                         $text,
 299                         $this->title->getFullUrl( 'diff=' . $rev->getId() . '&oldid=prev' ),
 300                         $rev->getTimestamp(),
 301                         $rev->getUserText(),
 302                         $this->title->getTalkPage()->getFullUrl()
 303                 );
 304         }
 305 }
 306
 307 /**
 308  * @ingroup Pager
 309  */
 310 class HistoryPager extends ReverseChronologicalPager {
 311         public $lastRow = false, $counter, $historyPage, $title, $buttons, $conds;
 312         protected $oldIdChecked;
 313
 314         function __construct( $historyPage, $year='', $month='', $tagFilter = '', $conds = array() ) {
 315                 parent::__construct();
 316                 $this->historyPage = $historyPage;
 317                 $this->title = $this->historyPage->title;
 318                 $this->tagFilter = $tagFilter;
 319                 $this->getDateCond( $year, $month );
 320                 $this->conds = $conds;
 321         }
 322
 323         // For hook compatibility...
 324         function getArticle() {
 325                 return $this->historyPage->getArticle();
 326         }
 327
 328         function getQueryInfo() {
 329                 $queryInfo = array(
 330                         'tables'  => array('revision'),
 331                         'fields'  => Revision::selectFields(),
 332                         'conds'   => array_merge(
 333                                 array( 'rev_page' => $this->historyPage->title->getArticleID() ),
 334                                 $this->conds ),
 335                         'options' => array( 'USE INDEX' => array('revision' => 'page_timestamp') ),
 336                         'join_conds' => array( 'tag_summary' => array( 'LEFT JOIN', 'ts_rev_id=rev_id' ) ),
 337                 );
 338                 ChangeTags::modifyDisplayQuery(
 339                         $queryInfo['tables'],
 340                         $queryInfo['fields'],
 341                         $queryInfo['conds'],
 342                         $queryInfo['join_conds'],
 343                         $queryInfo['options'],
 344                         $this->tagFilter
 345                 );
 346                 wfRunHooks( 'PageHistoryPager::getQueryInfo', array( &$this, &$queryInfo ) );
 347                 return $queryInfo;
 348         }
 349
 350         function getIndexField() {
 351                 return 'rev_timestamp';
 352         }
 353
 354         function formatRow( $row ) {
 355                 if( $this->lastRow ) {
 356                         $latest = ($this->counter == 1 && $this->mIsFirst);
 357                         $firstInList = $this->counter == 1;
 358                         $s = $this->historyLine( $this->lastRow, $row, $this->counter++,
 359                                 $this->title->getNotificationTimestamp(), $latest, $firstInList );
 360                 } else {
 361                         $s = '';
 362                 }
 363                 $this->lastRow = $row;
 364                 return $s;
 365         }
 366
 367         /**
 368          * Creates begin of history list with a submit button
 369          *
 370          * @return string HTML output
 371          */
 372         function getStartBody() {
 373                 global $wgScript, $wgUser, $wgOut, $wgContLang;
 374                 $this->lastRow = false;
 375                 $this->counter = 1;
 376                 $this->oldIdChecked = 0;
 377
 378                 $wgOut->wrapWikiMsg( "<div class='mw-history-legend'>\n$1</div>", 'histlegend' );
 379                 $s = Xml::openElement( 'form', array( 'action' => $wgScript,
 380                         'id' => 'mw-history-compare' ) ) . "\n";
 381                 $s .= Xml::hidden( 'title', $this->title->getPrefixedDbKey() ) . "\n";
 382                 $s .= Xml::hidden( 'action', 'historysubmit' ) . "\n";
 383
 384                 $this->buttons = '<div>';
 385                 if( $wgUser->isAllowed('deleterevision') ) {
 386                         $float = $wgContLang->alignEnd();
 387                         # Note bug #20966, <button> is non-standard in IE<8
 388                         $this->buttons .= Xml::element( 'button',
 389                                 array(
 390                                         'type' => 'submit',
 391                                         'name' => 'revisiondelete',
 392                                         'value' => '1',
 393                                         'style' => "float: $float;",
 394                                         'class' => 'mw-history-revisiondelete-button',
 395                                 ),
 396                                 wfMsg( 'showhideselectedversions' )
 397                         ) . "\n";
 398                 }
 399                 $this->buttons .= $this->submitButton( wfMsg( 'compareselectedversions'),
 400                         array(
 401                                 'class'     => 'historysubmit',
 402                                 'accesskey' => wfMsg( 'accesskey-compareselectedversions' ),
 403                                 'title'     => wfMsg( 'tooltip-compareselectedversions' ),
 404                         )
 405                 ) . "\n";
 406                 $this->buttons .= '</div>';
 407                 $s .= $this->buttons . '<ul id="pagehistory">' . "\n";
 408                 return $s;
 409         }
 410
 411         function getEndBody() {
 412                 if( $this->lastRow ) {
 413                         $latest = $this->counter == 1 && $this->mIsFirst;
 414                         $firstInList = $this->counter == 1;
 415                         if( $this->mIsBackwards ) {
 416                                 # Next row is unknown, but for UI reasons, probably exists if an offset has been specified
 417                                 if( $this->mOffset == '' ) {
 418                                         $next = null;
 419                                 } else {
 420                                         $next = 'unknown';
 421                                 }
 422                         } else {
 423                                 # The next row is the past-the-end row
 424                                 $next = $this->mPastTheEndRow;
 425                         }
 426                         $s = $this->historyLine( $this->lastRow, $next, $this->counter++,
 427                                 $this->title->getNotificationTimestamp(), $latest, $firstInList );
 428                 } else {
 429                         $s = '';
 430                 }
 431                 $s .= "</ul>\n";
 432                 # Add second buttons only if there is more than one rev
 433                 if( $this->getNumRows() > 2 ) {
 434                         $s .= $this->buttons;
 435                 }
 436                 $s .= '</form>';
 437                 return $s;
 438         }
 439
 440         /**
 441          * Creates a submit button
 442          *
 443          * @param $message String: text of the submit button, will be escaped
 444          * @param $attributes Array: attributes
 445          * @return String: HTML output for the submit button
 446          */
 447         function submitButton( $message, $attributes = array() ) {
 448                 # Disable submit button if history has 1 revision only
 449                 if( $this->getNumRows() > 1 ) {
 450                         return Xml::submitButton( $message , $attributes );
 451                 } else {
 452                         return '';
 453                 }
 454         }
 455
 456         /**
 457          * Returns a row from the history printout.
 458          *
 459          * @todo document some more, and maybe clean up the code (some params redundant?)
 460          *
 461          * @param $row Object: the database row corresponding to the previous line.
 462          * @param $next Mixed: the database row corresponding to the next line.
 463          * @param $counter Integer: apparently a counter of what row number we're at, counted from the top row = 1.
 464          * @param $notificationtimestamp
 465          * @param $latest Boolean: whether this row corresponds to the page's latest revision.
 466          * @param $firstInList Boolean: whether this row corresponds to the first displayed on this history page.
 467          * @return String: HTML output for the row
 468          */
 469         function historyLine( $row, $next, $counter = '', $notificationtimestamp = false,
 470                 $latest = false, $firstInList = false )
 471         {
 472                 global $wgUser, $wgLang;
 473                 $rev = new Revision( $row );
 474                 $rev->setTitle( $this->title );
 475
 476                 $curlink = $this->curLink( $rev, $latest );
 477                 $lastlink = $this->lastLink( $rev, $next, $counter );
 478                 $diffButtons = $this->diffButtons( $rev, $firstInList, $counter );
 479                 $histLinks = Html::rawElement(
 480                                 'span',
 481                                 array( 'class' => 'mw-history-histlinks' ),
 482                                 '(' . $curlink . $this->historyPage->message['pipe-separator'] . $lastlink . ') '
 483                 );
 484                 $s = $histLinks . $diffButtons;
 485
 486                 $link = $this->revLink( $rev );
 487                 $classes = array();
 488
 489                 $del = '';
 490                 // User can delete revisions...
 491                 if( $wgUser->isAllowed( 'deleterevision' ) ) {
 492                         // If revision was hidden from sysops, disable the checkbox
 493                         if( !$rev->userCan( Revision::DELETED_RESTRICTED ) ) {
 494                                 $del = Xml::check( 'deleterevisions', false, array( 'disabled' => 'disabled' ) );
 495                         // Otherwise, enable the checkbox...
 496                         } else {
 497                                 $del = Xml::check( 'showhiderevisions', false,
 498                                         array( 'name' => 'ids['.$rev->getId().']' ) );
 499                         }
 500                 // User can only view deleted revisions...
 501                 } else if( $rev->getVisibility() && $wgUser->isAllowed( 'deletedhistory' ) ) {
 502                         // If revision was hidden from sysops, disable the link
 503                         if( !$rev->userCan( Revision::DELETED_RESTRICTED ) ) {
 504                                 $cdel = $this->getSkin()->revDeleteLinkDisabled( false );
 505                         // Otherwise, show the link...
 506                         } else {
 507                                 $query = array( 'type' => 'revision',
 508                                         'target' => $this->title->getPrefixedDbkey(), 'ids' => $rev->getId() );
 509                                 $del .= $this->getSkin()->revDeleteLink( $query,
 510                                         $rev->isDeleted( Revision::DELETED_RESTRICTED ), false );
 511                         }
 512                 }
 513                 if( $del ) $s .= " $del ";
 514
 515                 $s .= " $link";
 516                 $s .= " <span class='history-user'>" .
 517                         $this->getSkin()->revUserTools( $rev, true ) . "</span>";
 518
 519                 if( $rev->isMinor() ) {
 520                         $s .= ' ' . ChangesList::flag( 'minor' );
 521                 }
 522
 523                 if( !is_null( $size = $rev->getSize() ) && !$rev->isDeleted( Revision::DELETED_TEXT ) ) {
 524                         $s .= ' ' . $this->getSkin()->formatRevisionSize( $size );
 525                 }
 526
 527                 $s .= $this->getSkin()->revComment( $rev, false, true );
 528
 529                 if( $notificationtimestamp && ($row->rev_timestamp >= $notificationtimestamp) ) {
 530                         $s .= ' <span class="updatedmarker">' .  wfMsgHtml( 'updatedmarker' ) . '</span>';
 531                 }
 532
 533                 $tools = array();
 534
 535                 # Rollback and undo links
 536                 if( !is_null( $next ) && is_object( $next ) ) {
 537                         if( $latest && $this->title->userCan( 'rollback' ) && $this->title->userCan( 'edit' ) ) {
 538                                 $tools[] = '<span class="mw-rollback-link">'.
 539                                         $this->getSkin()->buildRollbackLink( $rev ).'</span>';
 540                         }
 541
 542                         if( $this->title->quickUserCan( 'edit' )
 543                                 && !$rev->isDeleted( Revision::DELETED_TEXT )
 544                                 && !$next->rev_deleted & Revision::DELETED_TEXT )
 545                         {
 546                                 # Create undo tooltip for the first (=latest) line only
 547                                 $undoTooltip = $latest
 548                                         ? array( 'title' => wfMsg( 'tooltip-undo' ) )
 549                                         : array();
 550                                 $undolink = $this->getSkin()->link(
 551                                         $this->title,
 552                                         wfMsgHtml( 'editundo' ),
 553                                         $undoTooltip,
 554                                         array(
 555                                                 'action' => 'edit',
 556                                                 'undoafter' => $next->rev_id,
 557                                                 'undo' => $rev->getId()
 558                                         ),
 559                                         array( 'known', 'noclasses' )
 560                                 );
 561                                 $tools[] = "<span class=\"mw-history-undo\">{$undolink}</span>";
 562                         }
 563                 }
 564
 565                 if( $tools ) {
 566                         $s .= ' (' . $wgLang->pipeList( $tools ) . ')';
 567                 }
 568
 569                 # Tags
 570                 list($tagSummary, $newClasses) = ChangeTags::formatSummaryRow( $row->ts_tags, 'history' );
 571                 $classes = array_merge( $classes, $newClasses );
 572                 $s .= " $tagSummary";
 573
 574                 wfRunHooks( 'PageHistoryLineEnding', array( $this, &$row , &$s, &$classes ) );
 575
 576                 $attribs = array();
 577                 if ( $classes ) {
 578                         $attribs['class'] = implode( ' ', $classes );
 579                 }
 580
 581                 return Xml::tags( 'li', $attribs, $s ) . "\n";
 582         }
 583
 584         /**
 585          * Create a link to view this revision of the page
 586          *
 587          * @param $rev Revision
 588          * @return String
 589          */
 590         function revLink( $rev ) {
 591                 global $wgLang;
 592                 $date = $wgLang->timeanddate( wfTimestamp(TS_MW, $rev->getTimestamp()), true );
 593                 $date = htmlspecialchars( $date );
 594                 if( !$rev->isDeleted( Revision::DELETED_TEXT ) ) {
 595                         $link = $this->getSkin()->link(
 596                                 $this->title,
 597                                 $date,
 598                                 array(),
 599                                 array( 'oldid' => $rev->getId() ),
 600                                 array( 'known', 'noclasses' )
 601                         );
 602                 } else {
 603                         $link = "<span class=\"history-deleted\">$date</span>";
 604                 }
 605                 return $link;
 606         }
 607
 608         /**
 609          * Create a diff-to-current link for this revision for this page
 610          *
 611          * @param $rev Revision
 612          * @param $latest Boolean: this is the latest revision of the page?
 613          * @return String
 614          */
 615         function curLink( $rev, $latest ) {
 616                 $cur = $this->historyPage->message['cur'];
 617                 if( $latest || !$rev->userCan( Revision::DELETED_TEXT ) ) {
 618                         return $cur;
 619                 } else {
 620                         return $this->getSkin()->link(
 621                                 $this->title,
 622                                 $cur,
 623                                 array(),
 624                                 array(
 625                                         'diff' => $this->title->getLatestRevID(),
 626                                         'oldid' => $rev->getId()
 627                                 ),
 628                                 array( 'known', 'noclasses' )
 629                         );
 630                 }
 631         }
 632
 633         /**
 634          * Create a diff-to-previous link for this revision for this page.
 635          *
 636          * @param $prevRev Revision: the previous revision
 637          * @param $next Mixed: the newer revision
 638          * @param $counter Integer: what row on the history list this is
 639          * @return String
 640          */
 641         function lastLink( $prevRev, $next, $counter ) {
 642                 $last = $this->historyPage->message['last'];
 643                 # $next may either be a Row, null, or "unkown"
 644                 $nextRev = is_object($next) ? new Revision( $next ) : $next;
 645                 if( is_null($next) ) {
 646                         # Probably no next row
 647                         return $last;
 648                 } elseif( $next === 'unknown' ) {
 649                         # Next row probably exists but is unknown, use an oldid=prev link
 650                         return $this->getSkin()->link(
 651                                 $this->title,
 652                                 $last,
 653                                 array(),
 654                                 array(
 655                                         'diff' => $prevRev->getId(),
 656                                         'oldid' => 'prev'
 657                                 ),
 658                                 array( 'known', 'noclasses' )
 659                         );
 660                 } elseif( !$prevRev->userCan(Revision::DELETED_TEXT)
 661                         || !$nextRev->userCan(Revision::DELETED_TEXT) )
 662                 {
 663                         return $last;
 664                 } else {
 665                         return $this->getSkin()->link(
 666                                 $this->title,
 667                                 $last,
 668                                 array(),
 669                                 array(
 670                                         'diff' => $prevRev->getId(),
 671                                         'oldid' => $next->rev_id
 672                                 ),
 673                                 array( 'known', 'noclasses' )
 674                         );
 675                 }
 676         }
 677
 678         /**
 679          * Create radio buttons for page history
 680          *
 681          * @param $rev Revision object
 682          * @param $firstInList Boolean: is this version the first one?
 683          * @param $counter Integer: a counter of what row number we're at, counted from the top row = 1.
 684          * @return String: HTML output for the radio buttons
 685          */
 686         function diffButtons( $rev, $firstInList, $counter ) {
 687                 if( $this->getNumRows() > 1 ) {
 688                         $id = $rev->getId();
 689                         $radio = array( 'type'  => 'radio', 'value' => $id );
 690                         /** @todo: move title texts to javascript */
 691                         if( $firstInList ) {
 692                                 $first = Xml::element( 'input',
 693                                         array_merge( $radio, array(
 694                                                 'style' => 'visibility:hidden',
 695                                                 'name'  => 'oldid',
 696                                                 'id' => 'mw-oldid-null' ) )
 697                                 );
 698                                 $checkmark = array( 'checked' => 'checked' );
 699                         } else {
 700                                 # Check visibility of old revisions
 701                                 if( !$rev->userCan( Revision::DELETED_TEXT ) ) {
 702                                         $radio['disabled'] = 'disabled';
 703                                         $checkmark = array(); // We will check the next possible one
 704                                 } else if( $counter == 2 || !$this->oldIdChecked ) {
 705                                         $checkmark = array( 'checked' => 'checked' );
 706                                         $this->oldIdChecked = $id;
 707                                 } else {
 708                                         $checkmark = array();
 709                                 }
 710                                 $first = Xml::element( 'input',
 711                                         array_merge( $radio, $checkmark, array(
 712                                                 'name'  => 'oldid',
 713                                                 'id' => "mw-oldid-$id" ) ) );
 714                                 $checkmark = array();
 715                         }
 716                         $second = Xml::element( 'input',
 717                                 array_merge( $radio, $checkmark, array(
 718                                         'name'  => 'diff',
 719                                         'id' => "mw-diff-$id" ) ) );
 720                         return $first . $second;
 721                 } else {
 722                         return '';
 723                 }
 724         }
 725 }
 726
 727 /**
 728  * Backwards-compatibility aliases
 729  */
 730 class PageHistory extends HistoryPage {}
 731 class PageHistoryPager extends HistoryPager {}