Revert "Include short descriptions for extensions bundled in the release"

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

<?php
/**
 * Parent class for all special pages.
 *
 * 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
 */

/**
 * Parent class for all special pages.
 *
 * Includes some static functions for handling the special page list deprecated
 * in favor of SpecialPageFactory.
 *
 * @todo Turn this into a real ContextSource
 * @ingroup SpecialPage
 */
class SpecialPage {
        // The canonical name of this special page
        // Also used for the default <h1> heading, @see getDescription()
        protected $mName;

        // The local name of this special page
        private $mLocalName;

        // Minimum user level required to access this page, or "" for anyone.
        // Also used to categorise the pages in Special:Specialpages
        private $mRestriction;

        // Listed in Special:Specialpages?
        private $mListed;

        // Function name called by the default execute()
        private $mFunction;

        // File which needs to be included before the function above can be called
        private $mFile;

        // Whether or not this special page is being included from an article
        protected $mIncluding;

        // Whether the special page can be included in an article
        protected $mIncludable;

        /**
         * Current request context
         * @var IContextSource
         */
        protected $mContext;

        /**
         * Get a localised Title object for a specified special page name
         *
         * @param string $name
         * @param string|bool $subpage Subpage string, or false to not use a subpage
         * @param string $fragment The link fragment (after the "#")
         * @return Title
         * @throws MWException
         */
        public static function getTitleFor( $name, $subpage = false, $fragment = '' ) {
                $name = SpecialPageFactory::getLocalNameFor( $name, $subpage );
                return Title::makeTitle( NS_SPECIAL, $name, $fragment );
        }

        /**
         * Get a localised Title object for a page name with a possibly unvalidated subpage
         *
         * @param string $name
         * @param string|bool $subpage Subpage string, or false to not use a subpage
         * @return Title|null Title object or null if the page doesn't exist
         */
        public static function getSafeTitleFor( $name, $subpage = false ) {
                $name = SpecialPageFactory::getLocalNameFor( $name, $subpage );
                if ( $name ) {
                        return Title::makeTitleSafe( NS_SPECIAL, $name );
                } else {
                        return null;
                }
        }

        /**
         * Default constructor for special pages
         * Derivative classes should call this from their constructor
         *     Note that if the user does not have the required level, an error message will
         *     be displayed by the default execute() method, without the global function ever
         *     being called.
         *
         *     If you override execute(), you can recover the default behavior with userCanExecute()
         *     and displayRestrictionError()
         *
         * @param string $name Name of the special page, as seen in links and URLs
         * @param string $restriction User right required, e.g. "block" or "delete"
         * @param bool $listed Whether the page is listed in Special:Specialpages
         * @param callable|bool $function Function called by execute(). By default
         *   it is constructed from $name
         * @param string $file File which is included by execute(). It is also
         *   constructed from $name by default
         * @param bool $includable Whether the page can be included in normal pages
         */
        public function __construct(
                $name = '', $restriction = '', $listed = true,
                $function = false, $file = 'default', $includable = false
        ) {
                $this->mName = $name;
                $this->mRestriction = $restriction;
                $this->mListed = $listed;
                $this->mIncludable = $includable;
                if ( !$function ) {
                        $this->mFunction = 'wfSpecial' . $name;
                } else {
                        $this->mFunction = $function;
                }
                if ( $file === 'default' ) {
                        $this->mFile = __DIR__ . "/specials/Special$name.php";
                } else {
                        $this->mFile = $file;
                }
        }

        /**
         * Get the name of this Special Page.
         * @return string
         */
        function getName() {
                return $this->mName;
        }

        /**
         * Get the permission that a user must have to execute this page
         * @return string
         */
        function getRestriction() {
                return $this->mRestriction;
        }

        /**
         * Get the file which will be included by SpecialPage::execute() if your extension is
         * still stuck in the past and hasn't overridden the execute() method.  No modern code
         * should want or need to know this.
         * @return string
         * @deprecated since 1.18
         */
        function getFile() {
                wfDeprecated( __METHOD__, '1.18' );
                return $this->mFile;
        }

        // @todo FIXME: Decide which syntax to use for this, and stick to it
        /**
         * Whether this special page is listed in Special:SpecialPages
         * @since r3583 (v1.3)
         * @return bool
         */
        function isListed() {
                return $this->mListed;
        }
        /**
         * Set whether this page is listed in Special:Specialpages, at run-time
         * @since 1.3
         * @param bool $listed
         * @return bool
         */
        function setListed( $listed ) {
                return wfSetVar( $this->mListed, $listed );
        }
        /**
         * Get or set whether this special page is listed in Special:SpecialPages
         * @since 1.6
         * @param bool $x
         * @return bool
         */
        function listed( $x = null ) {
                return wfSetVar( $this->mListed, $x );
        }

        /**
         * Whether it's allowed to transclude the special page via {{Special:Foo/params}}
         * @return bool
         */
        public function isIncludable() {
                return $this->mIncludable;
        }

        /**
         * Whether the special page is being evaluated via transclusion
         * @param bool $x
         * @return bool
         */
        function including( $x = null ) {
                return wfSetVar( $this->mIncluding, $x );
        }

        /**
         * Get the localised name of the special page
         * @return string
         */
        function getLocalName() {
                if ( !isset( $this->mLocalName ) ) {
                        $this->mLocalName = SpecialPageFactory::getLocalNameFor( $this->mName );
                }
                return $this->mLocalName;
        }

        /**
         * Is this page expensive (for some definition of expensive)?
         * Expensive pages are disabled or cached in miser mode.  Originally used
         * (and still overridden) by QueryPage and subclasses, moved here so that
         * Special:SpecialPages can safely call it for all special pages.
         *
         * @return bool
         */
        public function isExpensive() {
                return false;
        }

        /**
         * Is this page cached?
         * Expensive pages are cached or disabled in miser mode.
         * Used by QueryPage and subclasses, moved here so that
         * Special:SpecialPages can safely call it for all special pages.
         *
         * @return bool
         * @since 1.21
         */
        public function isCached() {
                return false;
        }

        /**
         * Can be overridden by subclasses with more complicated permissions
         * schemes.
         *
         * @return bool Should the page be displayed with the restricted-access
         *   pages?
         */
        public function isRestricted() {
                // DWIM: If anons can do something, then it is not restricted
                return $this->mRestriction != '' && !User::groupHasPermission( '*', $this->mRestriction );
        }

        /**
         * Checks if the given user (identified by an object) can execute this
         * special page (as defined by $mRestriction).  Can be overridden by sub-
         * classes with more complicated permissions schemes.
         *
         * @param User $user The user to check
         * @return bool Does the user have permission to view the page?
         */
        public function userCanExecute( User $user ) {
                return $user->isAllowed( $this->mRestriction );
        }

        /**
         * Output an error message telling the user what access level they have to have
         * @throws PermissionsError
         */
        function displayRestrictionError() {
                throw new PermissionsError( $this->mRestriction );
        }

        /**
         * Checks if userCanExecute, and if not throws a PermissionsError
         *
         * @since 1.19
         * @return void
         * @throws PermissionsError
         */
        public function checkPermissions() {
                if ( !$this->userCanExecute( $this->getUser() ) ) {
                        $this->displayRestrictionError();
                }
        }

        /**
         * If the wiki is currently in readonly mode, throws a ReadOnlyError
         *
         * @since 1.19
         * @return void
         * @throws ReadOnlyError
         */
        public function checkReadOnly() {
                if ( wfReadOnly() ) {
                        throw new ReadOnlyError;
                }
        }

        /**
         * If the user is not logged in, throws UserNotLoggedIn error.
         *
         * Default error message includes a link to Special:Userlogin with properly set 'returnto' query
         * parameter.
         *
         * @since 1.23
         * @param string|Message $reasonMsg [optional] Passed on to UserNotLoggedIn constructor. Strings
         *     will be used as message keys. If a string is given, the message will also receive a
         *     formatted login link (generated using the 'loginreqlink' message) as first parameter. If a
         *     Message is given, it will be passed on verbatim.
         * @param string|Message $titleMsg [optional] Passed on to UserNotLoggedIn constructor. Strings
         *     will be used as message keys.
         * @throws UserNotLoggedIn
         */
        public function requireLogin( $reasonMsg = null, $titleMsg = null ) {
                if ( $this->getUser()->isAnon() ) {
                        // Use default messages if not given or explicit null passed
                        if ( !$reasonMsg ) {
                                $reasonMsg = 'exception-nologin-text-manual';
                        }
                        if ( !$titleMsg ) {
                                $titleMsg = 'exception-nologin';
                        }

                        // Convert to Messages with current context
                        if ( is_string( $reasonMsg ) ) {
                                $loginreqlink = Linker::linkKnown(
                                        SpecialPage::getTitleFor( 'Userlogin' ),
                                        $this->msg( 'loginreqlink' )->escaped(),
                                        array(),
                                        array( 'returnto' => $this->getPageTitle()->getPrefixedText() )
                                );
                                $reasonMsg = $this->msg( $reasonMsg )->rawParams( $loginreqlink );
                        }
                        if ( is_string( $titleMsg ) ) {
                                $titleMsg = $this->msg( $titleMsg );
                        }

                        throw new UserNotLoggedIn( $reasonMsg, $titleMsg );
                }
        }

        /**
         * Sets headers - this should be called from the execute() method of all derived classes!
         */
        function setHeaders() {
                $out = $this->getOutput();
                $out->setArticleRelated( false );
                $out->setRobotPolicy( "noindex,nofollow" );
                $out->setPageTitle( $this->getDescription() );
        }

        /**
         * Entry point.
         *
         * @since 1.20
         *
         * @param string|null $subPage
         */
        final public function run( $subPage ) {
                /**
                 * Gets called before @see SpecialPage::execute.
                 *
                 * @since 1.20
                 *
                 * @param SpecialPage $this
                 * @param string|null $subPage
                 */
                wfRunHooks( 'SpecialPageBeforeExecute', array( $this, $subPage ) );

                $this->beforeExecute( $subPage );
                $this->execute( $subPage );
                $this->afterExecute( $subPage );

                /**
                 * Gets called after @see SpecialPage::execute.
                 *
                 * @since 1.20
                 *
                 * @param SpecialPage $this
                 * @param string|null $subPage
                 */
                wfRunHooks( 'SpecialPageAfterExecute', array( $this, $subPage ) );
        }

        /**
         * Gets called before @see SpecialPage::execute.
         *
         * @since 1.20
         *
         * @param string|null $subPage
         */
        protected function beforeExecute( $subPage ) {
                // No-op
        }

        /**
         * Gets called after @see SpecialPage::execute.
         *
         * @since 1.20
         *
         * @param string|null $subPage
         */
        protected function afterExecute( $subPage ) {
                // No-op
        }

        /**
         * Default execute method
         * Checks user permissions, calls the function given in mFunction
         *
         * This must be overridden by subclasses; it will be made abstract in a future version
         *
         * @param string|null $subPage
         */
        public function execute( $subPage ) {
                $this->setHeaders();
                $this->checkPermissions();

                $func = $this->mFunction;
                // only load file if the function does not exist
                if ( !is_callable( $func ) && $this->mFile ) {
                        require_once $this->mFile;
                }
                $this->outputHeader();
                call_user_func( $func, $subPage, $this );
        }

        /**
         * Outputs a summary message on top of special pages
         * Per default the message key is the canonical name of the special page
         * May be overridden, i.e. by extensions to stick with the naming conventions
         * for message keys: 'extensionname-xxx'
         *
         * @param string $summaryMessageKey Message key of the summary
         */
        function outputHeader( $summaryMessageKey = '' ) {
                global $wgContLang;

                if ( $summaryMessageKey == '' ) {
                        $msg = $wgContLang->lc( $this->getName() ) . '-summary';
                } else {
                        $msg = $summaryMessageKey;
                }
                if ( !$this->msg( $msg )->isDisabled() && !$this->including() ) {
                        $this->getOutput()->wrapWikiMsg(
                                "<div class='mw-specialpage-summary'>\n$1\n</div>", $msg );
                }

        }

        /**
         * Returns the name that goes in the \<h1\> in the special page itself, and
         * also the name that will be listed in Special:Specialpages
         *
         * Derived classes can override this, but usually it is easier to keep the
         * default behavior.
         *
         * @return string
         */
        function getDescription() {
                return $this->msg( strtolower( $this->mName ) )->text();
        }

        /**
         * Get a self-referential title object
         *
         * @param string|bool $subpage
         * @return Title
         * @deprecated in 1.23, use SpecialPage::getPageTitle
         */
        function getTitle( $subpage = false ) {
                wfDeprecated( __METHOD__, '1.23' );
                return $this->getPageTitle( $subpage );
        }

        /**
         * Get a self-referential title object
         *
         * @param string|bool $subpage
         * @return Title
         * @since 1.23
         */
        function getPageTitle( $subpage = false ) {
                return self::getTitleFor( $this->mName, $subpage );
        }

        /**
         * Sets the context this SpecialPage is executed in
         *
         * @param IContextSource $context
         * @since 1.18
         */
        public function setContext( $context ) {
                $this->mContext = $context;
        }

        /**
         * Gets the context this SpecialPage is executed in
         *
         * @return IContextSource|RequestContext
         * @since 1.18
         */
        public function getContext() {
                if ( $this->mContext instanceof IContextSource ) {
                        return $this->mContext;
                } else {
                        wfDebug( __METHOD__ . " called and \$mContext is null. " .
                                "Return RequestContext::getMain(); for sanity\n" );
                        return RequestContext::getMain();
                }
        }

        /**
         * Get the WebRequest being used for this instance
         *
         * @return WebRequest
         * @since 1.18
         */
        public function getRequest() {
                return $this->getContext()->getRequest();
        }

        /**
         * Get the OutputPage being used for this instance
         *
         * @return OutputPage
         * @since 1.18
         */
        public function getOutput() {
                return $this->getContext()->getOutput();
        }

        /**
         * Shortcut to get the User executing this instance
         *
         * @return User
         * @since 1.18
         */
        public function getUser() {
                return $this->getContext()->getUser();
        }

        /**
         * Shortcut to get the skin being used for this instance
         *
         * @return Skin
         * @since 1.18
         */
        public function getSkin() {
                return $this->getContext()->getSkin();
        }

        /**
         * Shortcut to get user's language
         *
         * @deprecated since 1.19 Use getLanguage instead
         * @return Language
         * @since 1.18
         */
        public function getLang() {
                wfDeprecated( __METHOD__, '1.19' );
                return $this->getLanguage();
        }

        /**
         * Shortcut to get user's language
         *
         * @return Language
         * @since 1.19
         */
        public function getLanguage() {
                return $this->getContext()->getLanguage();
        }

        /**
         * Return the full title, including $par
         *
         * @return Title
         * @since 1.18
         */
        public function getFullTitle() {
                return $this->getContext()->getTitle();
        }

        /**
         * Wrapper around wfMessage that sets the current context.
         *
         * @return Message
         * @see wfMessage
         */
        public function msg( /* $args */ ) {
                $message = call_user_func_array(
                        array( $this->getContext(), 'msg' ),
                        func_get_args()
                );
                // RequestContext passes context to wfMessage, and the language is set from
                // the context, but setting the language for Message class removes the
                // interface message status, which breaks for example usernameless gender
                // invocations. Restore the flag when not including special page in content.
                if ( $this->including() ) {
                        $message->setInterfaceMessageFlag( false );
                }
                return $message;
        }

        /**
         * Adds RSS/atom links
         *
         * @param array $params
         */
        protected function addFeedLinks( $params ) {
                global $wgFeedClasses;

                $feedTemplate = wfScript( 'api' );

                foreach ( $wgFeedClasses as $format => $class ) {
                        $theseParams = $params + array( 'feedformat' => $format );
                        $url = wfAppendQuery( $feedTemplate, $theseParams );
                        $this->getOutput()->addFeedLink( $format, $url );
                }
        }

        /**
         * Get the group that the special page belongs in on Special:SpecialPage
         * Use this method, instead of getGroupName to allow customization
         * of the group name from the wiki side
         *
         * @return string Group of this special page
         * @since 1.21
         */
        public function getFinalGroupName() {
                global $wgSpecialPageGroups;
                $name = $this->getName();

                // Allow overbidding the group from the wiki side
                $msg = $this->msg( 'specialpages-specialpagegroup-' . strtolower( $name ) )->inContentLanguage();
                if ( !$msg->isBlank() ) {
                        $group = $msg->text();
                } else {
                        // Than use the group from this object
                        $group = $this->getGroupName();

                        // Group '-' is used as default to have the chance to determine,
                        // if the special pages overrides this method,
                        // if not overridden, $wgSpecialPageGroups is checked for b/c
                        if ( $group === '-' && isset( $wgSpecialPageGroups[$name] ) ) {
                                $group = $wgSpecialPageGroups[$name];
                        }
                }

                // never give '-' back, change to 'other'
                if ( $group === '-' ) {
                        $group = 'other';
                }

                return $group;
        }

        /**
         * Under which header this special page is listed in Special:SpecialPages
         * See messages 'specialpages-group-*' for valid names
         * This method defaults to group 'other'
         *
         * @return string
         * @since 1.21
         */
        protected function getGroupName() {
                // '-' used here to determine, if this group is overridden or has a hardcoded 'other'
                // Needed for b/c in getFinalGroupName
                return '-';
        }
}