Merge "API: Properly handle limit and continuation for generator=prefixsearch"

[mediawiki.git] / includes / specialpage / ChangesListSpecialPage.php

<?php
/**
 * Special page which uses a ChangesList to show query results.
 *
 * 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
 */

/**
 * Special page which uses a ChangesList to show query results.
 * @todo Way too many public functions, most of them should be protected
 *
 * @ingroup SpecialPage
 */
abstract class ChangesListSpecialPage extends SpecialPage {
        /** @var string */
        protected $rcSubpage;

        /** @var FormOptions */
        protected $rcOptions;

        /** @var array */
        protected $customFilters;

        /**
         * Main execution point
         *
         * @param string $subpage
         */
        public function execute( $subpage ) {
                $this->rcSubpage = $subpage;

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

                $rows = $this->getRows();
                $opts = $this->getOptions();
                if ( $rows === false ) {
                        if ( !$this->including() ) {
                                $this->doHeader( $opts, 0 );
                                $this->getOutput()->setStatusCode( 404 );
                        }

                        return;
                }

                $batch = new LinkBatch;
                foreach ( $rows as $row ) {
                        $batch->add( NS_USER, $row->rc_user_text );
                        $batch->add( NS_USER_TALK, $row->rc_user_text );
                        $batch->add( $row->rc_namespace, $row->rc_title );
                        if ( $row->rc_source === RecentChange::SRC_LOG ) {
                                $formatter = LogFormatter::newFromRow( $row );
                                foreach ( $formatter->getPreloadTitles() as $title ) {
                                        $batch->addObj( $title );
                                }
                        }
                }
                $batch->execute();

                $this->webOutput( $rows, $opts );

                $rows->free();
        }

        /**
         * Get the database result for this special page instance. Used by ApiFeedRecentChanges.
         *
         * @return bool|ResultWrapper Result or false
         */
        public function getRows() {
                $opts = $this->getOptions();
                $conds = $this->buildMainQueryConds( $opts );

                return $this->doMainQuery( $conds, $opts );
        }

        /**
         * Get the current FormOptions for this request
         *
         * @return FormOptions
         */
        public function getOptions() {
                if ( $this->rcOptions === null ) {
                        $this->rcOptions = $this->setup( $this->rcSubpage );
                }

                return $this->rcOptions;
        }

        /**
         * Create a FormOptions object with options as specified by the user
         *
         * @param array $parameters
         *
         * @return FormOptions
         */
        public function setup( $parameters ) {
                $opts = $this->getDefaultOptions();
                foreach ( $this->getCustomFilters() as $key => $params ) {
                        $opts->add( $key, $params['default'] );
                }

                $opts = $this->fetchOptionsFromRequest( $opts );

                // Give precedence to subpage syntax
                if ( $parameters !== null ) {
                        $this->parseParameters( $parameters, $opts );
                }

                $this->validateOptions( $opts );

                return $opts;
        }

        /**
         * Get a FormOptions object containing the default options. By default returns some basic options,
         * you might want to not call parent method and discard them, or to override default values.
         *
         * @return FormOptions
         */
        public function getDefaultOptions() {
                $opts = new FormOptions();

                $opts->add( 'hideminor', false );
                $opts->add( 'hidebots', false );
                $opts->add( 'hideanons', false );
                $opts->add( 'hideliu', false );
                $opts->add( 'hidepatrolled', false );
                $opts->add( 'hidemyself', false );

                $opts->add( 'namespace', '', FormOptions::INTNULL );
                $opts->add( 'invert', false );
                $opts->add( 'associated', false );

                return $opts;
        }

        /**
         * Get custom show/hide filters
         *
         * @return array Map of filter URL param names to properties (msg/default)
         */
        protected function getCustomFilters() {
                if ( $this->customFilters === null ) {
                        $this->customFilters = array();
                        Hooks::run( 'ChangesListSpecialPageFilters', array( $this, &$this->customFilters ) );
                }

                return $this->customFilters;
        }

        /**
         * Fetch values for a FormOptions object from the WebRequest associated with this instance.
         *
         * Intended for subclassing, e.g. to add a backwards-compatibility layer.
         *
         * @param FormOptions $opts
         * @return FormOptions
         */
        protected function fetchOptionsFromRequest( $opts ) {
                $opts->fetchValuesFromRequest( $this->getRequest() );

                return $opts;
        }

        /**
         * Process $par and put options found in $opts. Used when including the page.
         *
         * @param string $par
         * @param FormOptions $opts
         */
        public function parseParameters( $par, FormOptions $opts ) {
                // nothing by default
        }

        /**
         * Validate a FormOptions object generated by getDefaultOptions() with values already populated.
         *
         * @param FormOptions $opts
         */
        public function validateOptions( FormOptions $opts ) {
                // nothing by default
        }

        /**
         * Return an array of conditions depending of options set in $opts
         *
         * @param FormOptions $opts
         * @return array
         */
        public function buildMainQueryConds( FormOptions $opts ) {
                $dbr = $this->getDB();
                $user = $this->getUser();
                $conds = array();

                // It makes no sense to hide both anons and logged-in users. When this occurs, try a guess on
                // what the user meant and either show only bots or force anons to be shown.
                $botsonly = false;
                $hideanons = $opts['hideanons'];
                if ( $opts['hideanons'] && $opts['hideliu'] ) {
                        if ( $opts['hidebots'] ) {
                                $hideanons = false;
                        } else {
                                $botsonly = true;
                        }
                }

                // Toggles
                if ( $opts['hideminor'] ) {
                        $conds['rc_minor'] = 0;
                }
                if ( $opts['hidebots'] ) {
                        $conds['rc_bot'] = 0;
                }
                if ( $user->useRCPatrol() && $opts['hidepatrolled'] ) {
                        $conds['rc_patrolled'] = 0;
                }
                if ( $botsonly ) {
                        $conds['rc_bot'] = 1;
                } else {
                        if ( $opts['hideliu'] ) {
                                $conds[] = 'rc_user = 0';
                        }
                        if ( $hideanons ) {
                                $conds[] = 'rc_user != 0';
                        }
                }
                if ( $opts['hidemyself'] ) {
                        if ( $user->getId() ) {
                                $conds[] = 'rc_user != ' . $dbr->addQuotes( $user->getId() );
                        } else {
                                $conds[] = 'rc_user_text != ' . $dbr->addQuotes( $user->getName() );
                        }
                }

                // Namespace filtering
                if ( $opts['namespace'] !== '' ) {
                        $selectedNS = $dbr->addQuotes( $opts['namespace'] );
                        $operator = $opts['invert'] ? '!=' : '=';
                        $boolean = $opts['invert'] ? 'AND' : 'OR';

                        // Namespace association (bug 2429)
                        if ( !$opts['associated'] ) {
                                $condition = "rc_namespace $operator $selectedNS";
                        } else {
                                // Also add the associated namespace
                                $associatedNS = $dbr->addQuotes(
                                        MWNamespace::getAssociated( $opts['namespace'] )
                                );
                                $condition = "(rc_namespace $operator $selectedNS "
                                        . $boolean
                                        . " rc_namespace $operator $associatedNS)";
                        }

                        $conds[] = $condition;
                }

                return $conds;
        }

        /**
         * Process the query
         *
         * @param array $conds
         * @param FormOptions $opts
         * @return bool|ResultWrapper Result or false
         */
        public function doMainQuery( $conds, $opts ) {
                $tables = array( 'recentchanges' );
                $fields = RecentChange::selectFields();
                $query_options = array();
                $join_conds = array();

                ChangeTags::modifyDisplayQuery(
                        $tables,
                        $fields,
                        $conds,
                        $join_conds,
                        $query_options,
                        ''
                );

                if ( !$this->runMainQueryHook( $tables, $fields, $conds, $query_options, $join_conds,
                        $opts )
                ) {
                        return false;
                }

                $dbr = $this->getDB();

                return $dbr->select(
                        $tables,
                        $fields,
                        $conds,
                        __METHOD__,
                        $query_options,
                        $join_conds
                );
        }

        protected function runMainQueryHook( &$tables, &$fields, &$conds, &$query_options, &$join_conds, $opts ) {
                return Hooks::run(
                        'ChangesListSpecialPageQuery',
                        array( $this->getName(), &$tables, &$fields, &$conds, &$query_options, &$join_conds, $opts )
                );
        }

        /**
         * Return a IDatabase object for reading
         *
         * @return IDatabase
         */
        protected function getDB() {
                return wfGetDB( DB_SLAVE );
        }

        /**
         * Send output to the OutputPage object, only called if not used feeds
         *
         * @param ResultWrapper $rows Database rows
         * @param FormOptions $opts
         */
        public function webOutput( $rows, $opts ) {
                if ( !$this->including() ) {
                        $this->outputFeedLinks();
                        $this->doHeader( $opts, $rows->numRows() );
                }

                $this->outputChangesList( $rows, $opts );
        }

        /**
         * Output feed links.
         */
        public function outputFeedLinks() {
                // nothing by default
        }

        /**
         * Build and output the actual changes list.
         *
         * @param array $rows Database rows
         * @param FormOptions $opts
         */
        abstract public function outputChangesList( $rows, $opts );

        /**
         * Set the text to be displayed above the changes
         *
         * @param FormOptions $opts
         * @param int $numRows Number of rows in the result to show after this header
         */
        public function doHeader( $opts, $numRows ) {
                $this->setTopText( $opts );

                // @todo Lots of stuff should be done here.

                $this->setBottomText( $opts );
        }

        /**
         * Send the text to be displayed before the options. Should use $this->getOutput()->addWikiText()
         * or similar methods to print the text.
         *
         * @param FormOptions $opts
         */
        function setTopText( FormOptions $opts ) {
                // nothing by default
        }

        /**
         * Send the text to be displayed after the options. Should use $this->getOutput()->addWikiText()
         * or similar methods to print the text.
         *
         * @param FormOptions $opts
         */
        function setBottomText( FormOptions $opts ) {
                // nothing by default
        }

        /**
         * Get options to be displayed in a form
         * @todo This should handle options returned by getDefaultOptions().
         * @todo Not called by anything, should be called by something… doHeader() maybe?
         *
         * @param FormOptions $opts
         * @return array
         */
        function getExtraOptions( $opts ) {
                return array();
        }

        /**
         * Return the legend displayed within the fieldset
         * @todo This should not be static, then we can drop the parameter
         * @todo Not called by anything, should be called by doHeader()
         *
         * @param IContextSource $context The object available as $this in non-static functions
         * @return string
         */
        public static function makeLegend( IContextSource $context ) {
                $user = $context->getUser();
                # The legend showing what the letters and stuff mean
                $legend = Html::openElement( 'dl' ) . "\n";
                # Iterates through them and gets the messages for both letter and tooltip
                $legendItems = $context->getConfig()->get( 'RecentChangesFlags' );
                if ( !( $user->useRCPatrol() || $user->useNPPatrol() ) ) {
                        unset( $legendItems['unpatrolled'] );
                }
                foreach ( $legendItems as $key => $item ) { # generate items of the legend
                        $label = isset( $item['legend'] ) ? $item['legend'] : $item['title'];
                        $letter = $item['letter'];
                        $cssClass = isset( $item['class'] ) ? $item['class'] : $key;

                        $legend .= Html::element( 'dt',
                                array( 'class' => $cssClass ), $context->msg( $letter )->text()
                        ) . "\n" .
                        Html::rawElement( 'dd', array(),
                                $context->msg( $label )->parse()
                        ) . "\n";
                }
                # (+-123)
                $legend .= Html::rawElement( 'dt',
                        array( 'class' => 'mw-plusminus-pos' ),
                        $context->msg( 'recentchanges-legend-plusminus' )->parse()
                ) . "\n";
                $legend .= Html::element(
                        'dd',
                        array( 'class' => 'mw-changeslist-legend-plusminus' ),
                        $context->msg( 'recentchanges-label-plusminus' )->text()
                ) . "\n";
                $legend .= Html::closeElement( 'dl' ) . "\n";

                # Collapsibility
                $legend =
                        '<div class="mw-changeslist-legend">' .
                                $context->msg( 'recentchanges-legend-heading' )->parse() .
                                '<div class="mw-collapsible-content">' . $legend . '</div>' .
                        '</div>';

                return $legend;
        }

        /**
         * Add page-specific modules.
         */
        protected function addModules() {
                $out = $this->getOutput();
                // Styles and behavior for the legend box (see makeLegend())
                $out->addModuleStyles( 'mediawiki.special.changeslist.legend' );
                $out->addModules( 'mediawiki.special.changeslist.legend.js' );
        }

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