Move remaining LoadBalancer classes to Rdbms

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

<?php
/**
 * Implements Special:Redirect
 *
 * 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 redirects to: the user for a numeric user id,
 * the file for a given filename, or the page for a given revision id.
 *
 * @ingroup SpecialPage
 * @since 1.22
 */
class SpecialRedirect extends FormSpecialPage {

        /**
         * The type of the redirect (user/file/revision)
         *
         * @var string $mType
         * @example 'user'
         */
        protected $mType;

        /**
         * The identifier/value for the redirect (which id, which file)
         *
         * @var string $mValue
         * @example '42'
         */
        protected $mValue;

        function __construct() {
                parent::__construct( 'Redirect' );
                $this->mType = null;
                $this->mValue = null;
        }

        /**
         * Set $mType and $mValue based on parsed value of $subpage.
         * @param string $subpage
         */
        function setParameter( $subpage ) {
                // parse $subpage to pull out the parts
                $parts = explode( '/', $subpage, 2 );
                $this->mType = count( $parts ) > 0 ? $parts[0] : null;
                $this->mValue = count( $parts ) > 1 ? $parts[1] : null;
        }

        /**
         * Handle Special:Redirect/user/xxxx (by redirecting to User:YYYY)
         *
         * @return string|null Url to redirect to, or null if $mValue is invalid.
         */
        function dispatchUser() {
                if ( !ctype_digit( $this->mValue ) ) {
                        return null;
                }
                $user = User::newFromId( (int)$this->mValue );
                $username = $user->getName(); // load User as side-effect
                if ( $user->isAnon() ) {
                        return null;
                }
                $userpage = Title::makeTitle( NS_USER, $username );

                return $userpage->getFullURL( '', false, PROTO_CURRENT );
        }

        /**
         * Handle Special:Redirect/file/xxxx
         *
         * @return string|null Url to redirect to, or null if $mValue is not found.
         */
        function dispatchFile() {
                $title = Title::makeTitleSafe( NS_FILE, $this->mValue );

                if ( !$title instanceof Title ) {
                        return null;
                }
                $file = wfFindFile( $title );

                if ( !$file || !$file->exists() ) {
                        return null;
                }
                // Default behavior: Use the direct link to the file.
                $url = $file->getUrl();
                $request = $this->getRequest();
                $width = $request->getInt( 'width', -1 );
                $height = $request->getInt( 'height', -1 );

                // If a width is requested...
                if ( $width != -1 ) {
                        $mto = $file->transform( [ 'width' => $width, 'height' => $height ] );
                        // ... and we can
                        if ( $mto && !$mto->isError() ) {
                                // ... change the URL to point to a thumbnail.
                                $url = $mto->getUrl();
                        }
                }

                return $url;
        }

        /**
         * Handle Special:Redirect/revision/xxx
         * (by redirecting to index.php?oldid=xxx)
         *
         * @return string|null Url to redirect to, or null if $mValue is invalid.
         */
        function dispatchRevision() {
                $oldid = $this->mValue;
                if ( !ctype_digit( $oldid ) ) {
                        return null;
                }
                $oldid = (int)$oldid;
                if ( $oldid === 0 ) {
                        return null;
                }

                return wfAppendQuery( wfScript( 'index' ), [
                        'oldid' => $oldid
                ] );
        }

        /**
         * Handle Special:Redirect/page/xxx (by redirecting to index.php?curid=xxx)
         *
         * @return string|null Url to redirect to, or null if $mValue is invalid.
         */
        function dispatchPage() {
                $curid = $this->mValue;
                if ( !ctype_digit( $curid ) ) {
                        return null;
                }
                $curid = (int)$curid;
                if ( $curid === 0 ) {
                        return null;
                }

                return wfAppendQuery( wfScript( 'index' ), [
                        'curid' => $curid
                ] );
        }

        /**
         * Handle Special:Redirect/logid/xxx
         * (by redirecting to index.php?title=Special:Log)
         *
         * @since 1.27
         * @return string|null Url to redirect to, or null if $mValue is invalid.
         */
        function dispatchLog() {
                $logid = $this->mValue;
                if ( !ctype_digit( $logid ) ) {
                        return null;
                }
                $logid = (int)$logid;
                if ( $logid === 0 ) {
                        return null;
                }

                $logparams = [
                        'log_id',
                        'log_timestamp',
                        'log_type',
                        'log_user_text',
                ];

                $dbr = wfGetDB( DB_REPLICA );

                // Gets the nested SQL statement which
                // returns timestamp of the log with the given log ID
                $inner = $dbr->selectSQLText(
                        'logging',
                        [ 'log_timestamp' ],
                        [ 'log_id' => $logid ]
                );

                // Returns all fields mentioned in $logparams of the logs
                // with the same timestamp as the one returned by the statement above
                $logsSameTimestamps = $dbr->select(
                        'logging',
                        $logparams,
                        [ "log_timestamp = ($inner)" ]
                );
                if ( $logsSameTimestamps->numRows() === 0 ) {
                        return null;
                }

                // Stores the row with the same log ID as the one given
                $rowMain = [];
                foreach ( $logsSameTimestamps as $row ) {
                        if ( (int)$row->log_id === $logid ) {
                                $rowMain = $row;
                        }
                }

                array_shift( $logparams );

                // Stores all the rows with the same values in each column
                // as $rowMain
                foreach ( $logparams as $cond ) {
                        $matchedRows = [];
                        foreach ( $logsSameTimestamps as $row ) {
                                if ( $row->$cond === $rowMain->$cond ) {
                                        $matchedRows[] = $row;
                                }
                        }
                        if ( count( $matchedRows ) === 1 ) {
                                break;
                        }
                        $logsSameTimestamps = $matchedRows;
                }
                $query = [ 'title' => 'Special:Log', 'limit' => count( $matchedRows ) ];

                // A map of database field names from table 'logging' to the values of $logparams
                $keys = [
                        'log_timestamp' => 'offset',
                        'log_type' => 'type',
                        'log_user_text' => 'user'
                ];

                foreach ( $logparams as $logKey ) {
                        $query[$keys[$logKey]] = $matchedRows[0]->$logKey;
                }
                $query['offset'] = $query['offset'] + 1;
                $url = $query;

                return wfAppendQuery( wfScript( 'index' ), $url );
        }

        /**
         * Use appropriate dispatch* method to obtain a redirection URL,
         * and either: redirect, set a 404 error code and error message,
         * or do nothing (if $mValue wasn't set) allowing the form to be
         * displayed.
         *
         * @return bool True if a redirect was successfully handled.
         */
        function dispatch() {
                // the various namespaces supported by Special:Redirect
                switch ( $this->mType ) {
                        case 'user':
                                $url = $this->dispatchUser();
                                break;
                        case 'file':
                                $url = $this->dispatchFile();
                                break;
                        case 'revision':
                                $url = $this->dispatchRevision();
                                break;
                        case 'page':
                                $url = $this->dispatchPage();
                                break;
                        case 'logid':
                                $url = $this->dispatchLog();
                                break;
                        default:
                                $url = null;
                                break;
                }
                if ( $url ) {
                        $this->getOutput()->redirect( $url );

                        return true;
                }
                if ( !is_null( $this->mValue ) ) {
                        $this->getOutput()->setStatusCode( 404 );
                        // Message: redirect-not-exists
                        $msg = $this->getMessagePrefix() . '-not-exists';

                        return Status::newFatal( $msg );
                }

                return false;
        }

        protected function getFormFields() {
                $mp = $this->getMessagePrefix();
                $ns = [
                        // subpage => message
                        // Messages: redirect-user, redirect-page, redirect-revision,
                        // redirect-file, redirect-logid
                        'user' => $mp . '-user',
                        'page' => $mp . '-page',
                        'revision' => $mp . '-revision',
                        'file' => $mp . '-file',
                        'logid' => $mp . '-logid',
                ];
                $a = [];
                $a['type'] = [
                        'type' => 'select',
                        'label-message' => $mp . '-lookup', // Message: redirect-lookup
                        'options' => [],
                        'default' => current( array_keys( $ns ) ),
                ];
                foreach ( $ns as $n => $m ) {
                        $m = $this->msg( $m )->text();
                        $a['type']['options'][$m] = $n;
                }
                $a['value'] = [
                        'type' => 'text',
                        'label-message' => $mp . '-value' // Message: redirect-value
                ];
                // set the defaults according to the parsed subpage path
                if ( !empty( $this->mType ) ) {
                        $a['type']['default'] = $this->mType;
                }
                if ( !empty( $this->mValue ) ) {
                        $a['value']['default'] = $this->mValue;
                }

                return $a;
        }

        public function onSubmit( array $data ) {
                if ( !empty( $data['type'] ) && !empty( $data['value'] ) ) {
                        $this->setParameter( $data['type'] . '/' . $data['value'] );
                }

                /* if this returns false, will show the form */
                return $this->dispatch();
        }

        public function onSuccess() {
                /* do nothing, we redirect in $this->dispatch if successful. */
        }

        protected function alterForm( HTMLForm $form ) {
                /* display summary at top of page */
                $this->outputHeader();
                // tweak label on submit button
                // Message: redirect-submit
                $form->setSubmitTextMsg( $this->getMessagePrefix() . '-submit' );
                /* submit form every time */
                $form->setMethod( 'get' );
        }

        protected function getDisplayFormat() {
                return 'ooui';
        }

        /**
         * Return an array of subpages that this special page will accept.
         *
         * @return string[] subpages
         */
        protected function getSubpagesForPrefixSearch() {
                return [
                        'file',
                        'page',
                        'revision',
                        'user',
                        'logid',
                ];
        }

        /**
         * @return bool
         */
        public function requiresWrite() {
                return false;
        }

        /**
         * @return bool
         */
        public function requiresUnblock() {
                return false;
        }

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