Expose $wgMaxArticleSize in siteinfo query api

[mediawiki.git] / includes / specials / SpecialMovepage.php

<?php
/**
 * Implements Special:Movepage
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License along
 * with this program; if not, write to the Free Software Foundation, Inc.,
 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
 * http://www.gnu.org/copyleft/gpl.html
 *
 * @file
 * @ingroup SpecialPage
 */

/**
 * A special page that allows users to change page titles
 *
 * @ingroup SpecialPage
 */
class MovePageForm extends UnlistedSpecialPage {
        /** @var Title */
        protected $oldTitle = null;

        /** @var Title */
        protected $newTitle;

        /** @var string Text input */
        protected $reason;

        // Checks

        /** @var bool */
        protected $moveTalk;

        /** @var bool */
        protected $deleteAndMove;

        /** @var bool */
        protected $moveSubpages;

        /** @var bool */
        protected $fixRedirects;

        /** @var bool */
        protected $leaveRedirect;

        /** @var bool */
        protected $moveOverShared;

        private $watch = false;

        public function __construct() {
                parent::__construct( 'Movepage' );
        }

        public function doesWrites() {
                return true;
        }

        public function execute( $par ) {
                $this->useTransactionalTimeLimit();

                $this->checkReadOnly();

                $this->setHeaders();
                $this->outputHeader();

                $request = $this->getRequest();
                $target = !is_null( $par ) ? $par : $request->getVal( 'target' );

                // Yes, the use of getVal() and getText() is wanted, see bug 20365

                $oldTitleText = $request->getVal( 'wpOldTitle', $target );
                $this->oldTitle = Title::newFromText( $oldTitleText );

                if ( !$this->oldTitle ) {
                        // Either oldTitle wasn't passed, or newFromText returned null
                        throw new ErrorPageError( 'notargettitle', 'notargettext' );
                }
                if ( !$this->oldTitle->exists() ) {
                        throw new ErrorPageError( 'nopagetitle', 'nopagetext' );
                }

                $newTitleTextMain = $request->getText( 'wpNewTitleMain' );
                $newTitleTextNs = $request->getInt( 'wpNewTitleNs', $this->oldTitle->getNamespace() );
                // Backwards compatibility for forms submitting here from other sources
                // which is more common than it should be..
                $newTitleText_bc = $request->getText( 'wpNewTitle' );
                $this->newTitle = strlen( $newTitleText_bc ) > 0
                        ? Title::newFromText( $newTitleText_bc )
                        : Title::makeTitleSafe( $newTitleTextNs, $newTitleTextMain );

                $user = $this->getUser();

                # Check rights
                $permErrors = $this->oldTitle->getUserPermissionsErrors( 'move', $user );
                if ( count( $permErrors ) ) {
                        // Auto-block user's IP if the account was "hard" blocked
                        DeferredUpdates::addCallableUpdate( function() use ( $user ) {
                                $user->spreadAnyEditBlock();
                        } );
                        throw new PermissionsError( 'move', $permErrors );
                }

                $def = !$request->wasPosted();

                $this->reason = $request->getText( 'wpReason' );
                $this->moveTalk = $request->getBool( 'wpMovetalk', $def );
                $this->fixRedirects = $request->getBool( 'wpFixRedirects', $def );
                $this->leaveRedirect = $request->getBool( 'wpLeaveRedirect', $def );
                $this->moveSubpages = $request->getBool( 'wpMovesubpages' );
                $this->deleteAndMove = $request->getBool( 'wpDeleteAndMove' );
                $this->moveOverShared = $request->getBool( 'wpMoveOverSharedFile' );
                $this->watch = $request->getCheck( 'wpWatch' ) && $user->isLoggedIn();

                if ( 'submit' == $request->getVal( 'action' ) && $request->wasPosted()
                        && $user->matchEditToken( $request->getVal( 'wpEditToken' ) )
                ) {
                        $this->doSubmit();
                } else {
                        $this->showForm( [] );
                }
        }

        /**
         * Show the form
         *
         * @param array $err Error messages. Each item is an error message.
         *    It may either be a string message name or array message name and
         *    parameters, like the second argument to OutputPage::wrapWikiMsg().
         */
        function showForm( $err ) {
                global $wgContLang;

                $this->getSkin()->setRelevantTitle( $this->oldTitle );

                $out = $this->getOutput();
                $out->setPageTitle( $this->msg( 'move-page', $this->oldTitle->getPrefixedText() ) );
                $out->addModules( 'mediawiki.special.movePage' );
                $out->addModuleStyles( 'mediawiki.special.movePage.styles' );
                $this->addHelpLink( 'Help:Moving a page' );

                $out->addWikiMsg( $this->getConfig()->get( 'FixDoubleRedirects' ) ?
                        'movepagetext' :
                        'movepagetext-noredirectfixer'
                );

                if ( $this->oldTitle->getNamespace() == NS_USER && !$this->oldTitle->isSubpage() ) {
                        $out->wrapWikiMsg(
                                "<div class=\"warningbox mw-moveuserpage-warning\">\n$1\n</div>",
                                'moveuserpage-warning'
                        );
                } elseif ( $this->oldTitle->getNamespace() == NS_CATEGORY ) {
                        $out->wrapWikiMsg(
                                "<div class=\"warningbox mw-movecategorypage-warning\">\n$1\n</div>",
                                'movecategorypage-warning'
                        );
                }

                $deleteAndMove = false;
                $moveOverShared = false;

                $newTitle = $this->newTitle;

                if ( !$newTitle ) {
                        # Show the current title as a default
                        # when the form is first opened.
                        $newTitle = $this->oldTitle;
                } elseif ( !count( $err ) ) {
                        # If a title was supplied, probably from the move log revert
                        # link, check for validity. We can then show some diagnostic
                        # information and save a click.
                        $newerr = $this->oldTitle->isValidMoveOperation( $newTitle );
                        if ( is_array( $newerr ) ) {
                                $err = $newerr;
                        }
                }

                $user = $this->getUser();

                if ( count( $err ) == 1 && isset( $err[0][0] ) && $err[0][0] == 'articleexists'
                        && $newTitle->quickUserCan( 'delete', $user )
                ) {
                        $out->wrapWikiMsg(
                                "<div class='warningbox'>\n$1\n</div>\n",
                                [ 'delete_and_move_text', $newTitle->getPrefixedText() ]
                        );
                        $deleteAndMove = true;
                        $err = [];
                }

                if ( count( $err ) == 1 && isset( $err[0][0] ) && $err[0][0] == 'file-exists-sharedrepo'
                        && $user->isAllowed( 'reupload-shared' )
                ) {
                        $out->wrapWikiMsg(
                                "<div class='warningbox'>\n$1\n</div>\n",
                                [
                                        'move-over-sharedrepo',
                                        $newTitle->getPrefixedText()
                                ]
                        );
                        $moveOverShared = true;
                        $err = [];
                }

                $oldTalk = $this->oldTitle->getTalkPage();
                $oldTitleSubpages = $this->oldTitle->hasSubpages();
                $oldTitleTalkSubpages = $this->oldTitle->getTalkPage()->hasSubpages();

                $canMoveSubpage = ( $oldTitleSubpages || $oldTitleTalkSubpages ) &&
                        !count( $this->oldTitle->getUserPermissionsErrors( 'move-subpages', $user ) );

                # We also want to be able to move assoc. subpage talk-pages even if base page
                # has no associated talk page, so || with $oldTitleTalkSubpages.
                $considerTalk = !$this->oldTitle->isTalkPage() &&
                        ( $oldTalk->exists()
                                || ( $oldTitleTalkSubpages && $canMoveSubpage ) );

                $dbr = wfGetDB( DB_SLAVE );
                if ( $this->getConfig()->get( 'FixDoubleRedirects' ) ) {
                        $hasRedirects = $dbr->selectField( 'redirect', '1',
                                [
                                        'rd_namespace' => $this->oldTitle->getNamespace(),
                                        'rd_title' => $this->oldTitle->getDBkey(),
                                ], __METHOD__ );
                } else {
                        $hasRedirects = false;
                }

                if ( count( $err ) ) {
                        $out->addHTML( "<div class='errorbox'>\n" );
                        $action_desc = $this->msg( 'action-move' )->plain();
                        $out->addWikiMsg( 'permissionserrorstext-withaction', count( $err ), $action_desc );

                        if ( count( $err ) == 1 ) {
                                $errMsg = $err[0];
                                $errMsgName = array_shift( $errMsg );

                                if ( $errMsgName == 'hookaborted' ) {
                                        $out->addHTML( "<p>{$errMsg[0]}</p>\n" );
                                } else {
                                        $out->addWikiMsgArray( $errMsgName, $errMsg );
                                }
                        } else {
                                $errStr = [];

                                foreach ( $err as $errMsg ) {
                                        if ( $errMsg[0] == 'hookaborted' ) {
                                                $errStr[] = $errMsg[1];
                                        } else {
                                                $errMsgName = array_shift( $errMsg );
                                                $errStr[] = $this->msg( $errMsgName, $errMsg )->parse();
                                        }
                                }

                                $out->addHTML( '<ul><li>' . implode( "</li>\n<li>", $errStr ) . "</li></ul>\n" );
                        }
                        $out->addHTML( "</div>\n" );
                }

                if ( $this->oldTitle->isProtected( 'move' ) ) {
                        # Is the title semi-protected?
                        if ( $this->oldTitle->isSemiProtected( 'move' ) ) {
                                $noticeMsg = 'semiprotectedpagemovewarning';
                                $classes[] = 'mw-textarea-sprotected';
                        } else {
                                # Then it must be protected based on static groups (regular)
                                $noticeMsg = 'protectedpagemovewarning';
                                $classes[] = 'mw-textarea-protected';
                        }
                        $out->addHTML( "<div class='mw-warning-with-logexcerpt'>\n" );
                        $out->addWikiMsg( $noticeMsg );
                        LogEventsList::showLogExtract(
                                $out,
                                'protect',
                                $this->oldTitle,
                                '',
                                [ 'lim' => 1 ]
                        );
                        $out->addHTML( "</div>\n" );
                }

                // Byte limit (not string length limit) for wpReason and wpNewTitleMain
                // is enforced in the mediawiki.special.movePage module

                $immovableNamespaces = [];
                foreach ( array_keys( $this->getLanguage()->getNamespaces() ) as $nsId ) {
                        if ( !MWNamespace::isMovable( $nsId ) ) {
                                $immovableNamespaces[] = $nsId;
                        }
                }

                $handler = ContentHandler::getForTitle( $this->oldTitle );

                $out->enableOOUI();
                $fields = [];

                $fields[] = new OOUI\FieldLayout(
                        new MediaWiki\Widget\ComplexTitleInputWidget( [
                                'id' => 'wpNewTitle',
                                'namespace' => [
                                        'id' => 'wpNewTitleNs',
                                        'name' => 'wpNewTitleNs',
                                        'value' => $newTitle->getNamespace(),
                                        'exclude' => $immovableNamespaces,
                                ],
                                'title' => [
                                        'id' => 'wpNewTitleMain',
                                        'name' => 'wpNewTitleMain',
                                        'value' => $wgContLang->recodeForEdit( $newTitle->getText() ),
                                        // Inappropriate, since we're expecting the user to input a non-existent page's title
                                        'suggestions' => false,
                                ],
                                'infusable' => true,
                        ] ),
                        [
                                'label' => $this->msg( 'newtitle' )->text(),
                                'align' => 'top',
                        ]
                );

                $fields[] = new OOUI\FieldLayout(
                        new OOUI\TextInputWidget( [
                                'name' => 'wpReason',
                                'id' => 'wpReason',
                                'maxLength' => 200,
                                'infusable' => true,
                                'value' => $this->reason,
                        ] ),
                        [
                                'label' => $this->msg( 'movereason' )->text(),
                                'align' => 'top',
                        ]
                );

                if ( $considerTalk ) {
                        $fields[] = new OOUI\FieldLayout(
                                new OOUI\CheckboxInputWidget( [
                                        'name' => 'wpMovetalk',
                                        'id' => 'wpMovetalk',
                                        'value' => '1',
                                        'selected' => $this->moveTalk,
                                ] ),
                                [
                                        'label' => $this->msg( 'movetalk' )->text(),
                                        'help' => new OOUI\HtmlSnippet( $this->msg( 'movepagetalktext' )->parseAsBlock() ),
                                        'align' => 'inline',
                                        'infusable' => true,
                                ]
                        );
                }

                if ( $user->isAllowed( 'suppressredirect' ) ) {
                        if ( $handler->supportsRedirects() ) {
                                $isChecked = $this->leaveRedirect;
                                $isDisabled = false;
                        } else {
                                $isChecked = false;
                                $isDisabled = true;
                        }
                        $fields[] = new OOUI\FieldLayout(
                                new OOUI\CheckboxInputWidget( [
                                        'name' => 'wpLeaveRedirect',
                                        'id' => 'wpLeaveRedirect',
                                        'value' => '1',
                                        'selected' => $isChecked,
                                        'disabled' => $isDisabled,
                                ] ),
                                [
                                        'label' => $this->msg( 'move-leave-redirect' )->text(),
                                        'align' => 'inline',
                                ]
                        );
                }

                if ( $hasRedirects ) {
                        $fields[] = new OOUI\FieldLayout(
                                new OOUI\CheckboxInputWidget( [
                                        'name' => 'wpFixRedirects',
                                        'id' => 'wpFixRedirects',
                                        'value' => '1',
                                        'selected' => $this->fixRedirects,
                                ] ),
                                [
                                        'label' => $this->msg( 'fix-double-redirects' )->text(),
                                        'align' => 'inline',
                                ]
                        );
                }

                if ( $canMoveSubpage ) {
                        $maximumMovedPages = $this->getConfig()->get( 'MaximumMovedPages' );
                        $fields[] = new OOUI\FieldLayout(
                                new OOUI\CheckboxInputWidget( [
                                        'name' => 'wpMovesubpages',
                                        'id' => 'wpMovesubpages',
                                        'value' => '1',
                                        # Don't check the box if we only have talk subpages to
                                        # move and we aren't moving the talk page.
                                        'selected' => $this->moveSubpages && ( $this->oldTitle->hasSubpages() || $this->moveTalk ),
                                ] ),
                                [
                                        'label' => new OOUI\HtmlSnippet(
                                                $this->msg(
                                                        ( $this->oldTitle->hasSubpages()
                                                                ? 'move-subpages'
                                                                : 'move-talk-subpages' )
                                                )->numParams( $maximumMovedPages )->params( $maximumMovedPages )->parse()
                                        ),
                                        'align' => 'inline',
                                ]
                        );
                }

                # Don't allow watching if user is not logged in
                if ( $user->isLoggedIn() ) {
                        $watchChecked = $user->isLoggedIn() && ( $this->watch || $user->getBoolOption( 'watchmoves' )
                                || $user->isWatched( $this->oldTitle ) );
                        $fields[] = new OOUI\FieldLayout(
                                new OOUI\CheckboxInputWidget( [
                                        'name' => 'wpWatch',
                                        'id' => 'watch', # ew
                                        'value' => '1',
                                        'selected' => $watchChecked,
                                ] ),
                                [
                                        'label' => $this->msg( 'move-watch' )->text(),
                                        'align' => 'inline',
                                ]
                        );
                }

                $hiddenFields = '';
                if ( $moveOverShared ) {
                        $hiddenFields .= Html::hidden( 'wpMoveOverSharedFile', '1' );
                }

                if ( $deleteAndMove ) {
                        $fields[] = new OOUI\FieldLayout(
                                new OOUI\CheckboxInputWidget( [
                                        'name' => 'wpDeleteAndMove',
                                        'id' => 'wpDeleteAndMove',
                                        'value' => '1',
                                ] ),
                                [
                                        'label' => $this->msg( 'delete_and_move_confirm' )->text(),
                                        'align' => 'inline',
                                ]
                        );
                }

                $fields[] = new OOUI\FieldLayout(
                        new OOUI\ButtonInputWidget( [
                                'name' => 'wpMove',
                                'value' => $this->msg( 'movepagebtn' )->text(),
                                'label' => $this->msg( 'movepagebtn' )->text(),
                                'flags' => [ 'constructive', 'primary' ],
                                'type' => 'submit',
                        ] ),
                        [
                                'align' => 'top',
                        ]
                );

                $fieldset = new OOUI\FieldsetLayout( [
                        'label' => $this->msg( 'move-page-legend' )->text(),
                        'id' => 'mw-movepage-table',
                        'items' => $fields,
                ] );

                $form = new OOUI\FormLayout( [
                        'method' => 'post',
                        'action' => $this->getPageTitle()->getLocalURL( 'action=submit' ),
                        'id' => 'movepage',
                ] );
                $form->appendContent(
                        $fieldset,
                        new OOUI\HtmlSnippet(
                                $hiddenFields .
                                Html::hidden( 'wpOldTitle', $this->oldTitle->getPrefixedText() ) .
                                Html::hidden( 'wpEditToken', $user->getEditToken() )
                        )
                );

                $out->addHTML(
                        new OOUI\PanelLayout( [
                                'classes' => [ 'movepage-wrapper' ],
                                'expanded' => false,
                                'padded' => true,
                                'framed' => true,
                                'content' => $form,
                        ] )
                );

                $this->showLogFragment( $this->oldTitle );
                $this->showSubpages( $this->oldTitle );
        }

        function doSubmit() {
                $user = $this->getUser();

                if ( $user->pingLimiter( 'move' ) ) {
                        throw new ThrottledError;
                }

                $ot = $this->oldTitle;
                $nt = $this->newTitle;

                # don't allow moving to pages with # in
                if ( !$nt || $nt->hasFragment() ) {
                        $this->showForm( [ [ 'badtitletext' ] ] );

                        return;
                }

                # Show a warning if the target file exists on a shared repo
                if ( $nt->getNamespace() == NS_FILE
                        && !( $this->moveOverShared && $user->isAllowed( 'reupload-shared' ) )
                        && !RepoGroup::singleton()->getLocalRepo()->findFile( $nt )
                        && wfFindFile( $nt )
                ) {
                        $this->showForm( [ [ 'file-exists-sharedrepo' ] ] );

                        return;
                }

                # Delete to make way if requested
                if ( $this->deleteAndMove ) {
                        $permErrors = $nt->getUserPermissionsErrors( 'delete', $user );
                        if ( count( $permErrors ) ) {
                                # Only show the first error
                                $this->showForm( $permErrors );

                                return;
                        }

                        $reason = $this->msg( 'delete_and_move_reason', $ot )->inContentLanguage()->text();

                        // Delete an associated image if there is
                        if ( $nt->getNamespace() == NS_FILE ) {
                                $file = wfLocalFile( $nt );
                                $file->load( File::READ_LATEST );
                                if ( $file->exists() ) {
                                        $file->delete( $reason, false, $user );
                                }
                        }

                        $error = ''; // passed by ref
                        $page = WikiPage::factory( $nt );
                        $deleteStatus = $page->doDeleteArticleReal( $reason, false, 0, true, $error, $user );
                        if ( !$deleteStatus->isGood() ) {
                                $this->showForm( $deleteStatus->getErrorsArray() );

                                return;
                        }
                }

                $handler = ContentHandler::getForTitle( $ot );

                if ( !$handler->supportsRedirects() ) {
                        $createRedirect = false;
                } elseif ( $user->isAllowed( 'suppressredirect' ) ) {
                        $createRedirect = $this->leaveRedirect;
                } else {
                        $createRedirect = true;
                }

                # Do the actual move.
                $mp = new MovePage( $ot, $nt );
                $valid = $mp->isValidMove();
                if ( !$valid->isOK() ) {
                        $this->showForm( $valid->getErrorsArray() );
                        return;
                }

                $permStatus = $mp->checkPermissions( $user, $this->reason );
                if ( !$permStatus->isOK() ) {
                        $this->showForm( $permStatus->getErrorsArray() );
                        return;
                }

                $status = $mp->move( $user, $this->reason, $createRedirect );
                if ( !$status->isOK() ) {
                        $this->showForm( $status->getErrorsArray() );
                        return;
                }

                if ( $this->getConfig()->get( 'FixDoubleRedirects' ) && $this->fixRedirects ) {
                        DoubleRedirectJob::fixRedirects( 'move', $ot, $nt );
                }

                $out = $this->getOutput();
                $out->setPageTitle( $this->msg( 'pagemovedsub' ) );

                $linkRenderer = $this->getLinkRenderer();
                $oldLink = $linkRenderer->makeLink(
                        $ot,
                        null,
                        [ 'id' => 'movepage-oldlink' ],
                        [ 'redirect' => 'no' ]
                );
                $newLink = $linkRenderer->makeKnownLink(
                        $nt,
                        null,
                        [ 'id' => 'movepage-newlink' ]
                );
                $oldText = $ot->getPrefixedText();
                $newText = $nt->getPrefixedText();

                if ( $ot->exists() ) {
                        // NOTE: we assume that if the old title exists, it's because it was re-created as
                        // a redirect to the new title. This is not safe, but what we did before was
                        // even worse: we just determined whether a redirect should have been created,
                        // and reported that it was created if it should have, without any checks.
                        // Also note that isRedirect() is unreliable because of bug 37209.
                        $msgName = 'movepage-moved-redirect';
                } else {
                        $msgName = 'movepage-moved-noredirect';
                }

                $out->addHTML( $this->msg( 'movepage-moved' )->rawParams( $oldLink,
                        $newLink )->params( $oldText, $newText )->parseAsBlock() );
                $out->addWikiMsg( $msgName );

                Hooks::run( 'SpecialMovepageAfterMove', [ &$this, &$ot, &$nt ] );

                # Now we move extra pages we've been asked to move: subpages and talk
                # pages.  First, if the old page or the new page is a talk page, we
                # can't move any talk pages: cancel that.
                if ( $ot->isTalkPage() || $nt->isTalkPage() ) {
                        $this->moveTalk = false;
                }

                if ( count( $ot->getUserPermissionsErrors( 'move-subpages', $user ) ) ) {
                        $this->moveSubpages = false;
                }

                /**
                 * Next make a list of id's.  This might be marginally less efficient
                 * than a more direct method, but this is not a highly performance-cri-
                 * tical code path and readable code is more important here.
                 *
                 * If the target namespace doesn't allow subpages, moving with subpages
                 * would mean that you couldn't move them back in one operation, which
                 * is bad.
                 * @todo FIXME: A specific error message should be given in this case.
                 */

                // @todo FIXME: Use Title::moveSubpages() here
                $dbr = wfGetDB( DB_MASTER );
                if ( $this->moveSubpages && (
                        MWNamespace::hasSubpages( $nt->getNamespace() ) || (
                                $this->moveTalk
                                        && MWNamespace::hasSubpages( $nt->getTalkPage()->getNamespace() )
                        )
                ) ) {
                        $conds = [
                                'page_title' . $dbr->buildLike( $ot->getDBkey() . '/', $dbr->anyString() )
                                        . ' OR page_title = ' . $dbr->addQuotes( $ot->getDBkey() )
                        ];
                        $conds['page_namespace'] = [];
                        if ( MWNamespace::hasSubpages( $nt->getNamespace() ) ) {
                                $conds['page_namespace'][] = $ot->getNamespace();
                        }
                        if ( $this->moveTalk &&
                                MWNamespace::hasSubpages( $nt->getTalkPage()->getNamespace() )
                        ) {
                                $conds['page_namespace'][] = $ot->getTalkPage()->getNamespace();
                        }
                } elseif ( $this->moveTalk ) {
                        $conds = [
                                'page_namespace' => $ot->getTalkPage()->getNamespace(),
                                'page_title' => $ot->getDBkey()
                        ];
                } else {
                        # Skip the query
                        $conds = null;
                }

                $extraPages = [];
                if ( !is_null( $conds ) ) {
                        $extraPages = TitleArray::newFromResult(
                                $dbr->select( 'page',
                                        [ 'page_id', 'page_namespace', 'page_title' ],
                                        $conds,
                                        __METHOD__
                                )
                        );
                }

                $extraOutput = [];
                $count = 1;
                foreach ( $extraPages as $oldSubpage ) {
                        if ( $ot->equals( $oldSubpage ) || $nt->equals( $oldSubpage ) ) {
                                # Already did this one.
                                continue;
                        }

                        $newPageName = preg_replace(
                                '#^' . preg_quote( $ot->getDBkey(), '#' ) . '#',
                                StringUtils::escapeRegexReplacement( $nt->getDBkey() ), # bug 21234
                                $oldSubpage->getDBkey()
                        );

                        if ( $oldSubpage->isSubpage() && ( $ot->isTalkPage() xor $nt->isTalkPage() ) ) {
                                // Moving a subpage from a subject namespace to a talk namespace or vice-versa
                                $newNs = $nt->getNamespace();
                        } elseif ( $oldSubpage->isTalkPage() ) {
                                $newNs = $nt->getTalkPage()->getNamespace();
                        } else {
                                $newNs = $nt->getSubjectPage()->getNamespace();
                        }

                        # Bug 14385: we need makeTitleSafe because the new page names may
                        # be longer than 255 characters.
                        $newSubpage = Title::makeTitleSafe( $newNs, $newPageName );
                        if ( !$newSubpage ) {
                                $oldLink = $linkRenderer->makeKnownLink( $oldSubpage );
                                $extraOutput[] = $this->msg( 'movepage-page-unmoved' )->rawParams( $oldLink )
                                        ->params( Title::makeName( $newNs, $newPageName ) )->escaped();
                                continue;
                        }

                        # This was copy-pasted from Renameuser, bleh.
                        if ( $newSubpage->exists() && !$oldSubpage->isValidMoveTarget( $newSubpage ) ) {
                                $link = $linkRenderer->makeKnownLink( $newSubpage );
                                $extraOutput[] = $this->msg( 'movepage-page-exists' )->rawParams( $link )->escaped();
                        } else {
                                $success = $oldSubpage->moveTo( $newSubpage, true, $this->reason, $createRedirect );

                                if ( $success === true ) {
                                        if ( $this->fixRedirects ) {
                                                DoubleRedirectJob::fixRedirects( 'move', $oldSubpage, $newSubpage );
                                        }
                                        $oldLink = $linkRenderer->makeLink(
                                                $oldSubpage,
                                                null,
                                                [],
                                                [ 'redirect' => 'no' ]
                                        );

                                        $newLink = $linkRenderer->makeKnownLink( $newSubpage );
                                        $extraOutput[] = $this->msg( 'movepage-page-moved' )
                                                ->rawParams( $oldLink, $newLink )->escaped();
                                        ++$count;

                                        $maximumMovedPages = $this->getConfig()->get( 'MaximumMovedPages' );
                                        if ( $count >= $maximumMovedPages ) {
                                                $extraOutput[] = $this->msg( 'movepage-max-pages' )
                                                        ->numParams( $maximumMovedPages )->escaped();
                                                break;
                                        }
                                } else {
                                        $oldLink = $linkRenderer->makeKnownLink( $oldSubpage );
                                        $newLink = $linkRenderer->makeLink( $newSubpage );
                                        $extraOutput[] = $this->msg( 'movepage-page-unmoved' )
                                                ->rawParams( $oldLink, $newLink )->escaped();
                                }
                        }
                }

                if ( $extraOutput !== [] ) {
                        $out->addHTML( "<ul>\n<li>" . implode( "</li>\n<li>", $extraOutput ) . "</li>\n</ul>" );
                }

                # Deal with watches (we don't watch subpages)
                WatchAction::doWatchOrUnwatch( $this->watch, $ot, $user );
                WatchAction::doWatchOrUnwatch( $this->watch, $nt, $user );
        }

        function showLogFragment( $title ) {
                $moveLogPage = new LogPage( 'move' );
                $out = $this->getOutput();
                $out->addHTML( Xml::element( 'h2', null, $moveLogPage->getName()->text() ) );
                LogEventsList::showLogExtract( $out, 'move', $title );
        }

        function showSubpages( $title ) {
                if ( !MWNamespace::hasSubpages( $title->getNamespace() ) ) {
                        return;
                }

                $subpages = $title->getSubpages();
                $count = $subpages instanceof TitleArray ? $subpages->count() : 0;

                $out = $this->getOutput();
                $out->wrapWikiMsg( '== $1 ==', [ 'movesubpage', $count ] );

                # No subpages.
                if ( $count == 0 ) {
                        $out->addWikiMsg( 'movenosubpage' );

                        return;
                }

                $out->addWikiMsg( 'movesubpagetext', $this->getLanguage()->formatNum( $count ) );
                $out->addHTML( "<ul>\n" );

                $linkRenderer = $this->getLinkRenderer();
                foreach ( $subpages as $subpage ) {
                        $link = $linkRenderer->makeLink( $subpage );
                        $out->addHTML( "<li>$link</li>\n" );
                }
                $out->addHTML( "</ul>\n" );
        }

        /**
         * Return an array of subpages beginning with $search that this special page will accept.
         *
         * @param string $search Prefix to search for
         * @param int $limit Maximum number of results to return (usually 10)
         * @param int $offset Number of results to skip (usually 0)
         * @return string[] Matching subpages
         */
        public function prefixSearchSubpages( $search, $limit, $offset ) {
                return $this->prefixSearchString( $search, $limit, $offset );
        }

        protected function getGroupName() {
                return 'pagetools';
        }
}