Merge "Special:Upload should not crash on failing previews"

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

<?php
/**
 * Implements Special:Booksources
 *
 * 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 outputs information on sourcing a book with a particular ISBN
 * The parser creates links to this page when dealing with ISBNs in wikitext
 *
 * @author Rob Church <robchur@gmail.com>
 * @ingroup SpecialPage
 */
class SpecialBookSources extends SpecialPage {
        public function __construct() {
                parent::__construct( 'Booksources' );
        }

        /**
         * Show the special page
         *
         * @param string $isbn ISBN passed as a subpage parameter
         */
        public function execute( $isbn ) {
                $out = $this->getOutput();

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

                // User provided ISBN
                $isbn = $isbn ?: $this->getRequest()->getText( 'isbn' );
                $isbn = trim( $isbn );

                $this->buildForm( $isbn );

                if ( $isbn !== '' ) {
                        if ( !self::isValidISBN( $isbn ) ) {
                                $out->wrapWikiMsg(
                                        "<div class=\"error\">\n$1\n</div>",
                                        'booksources-invalid-isbn'
                                );
                        }

                        $this->showList( $isbn );
                }
        }

        /**
         * Return whether a given ISBN (10 or 13) is valid.
         *
         * @param string $isbn ISBN passed for check
         * @return bool
         */
        public static function isValidISBN( $isbn ) {
                $isbn = self::cleanIsbn( $isbn );
                $sum = 0;
                if ( strlen( $isbn ) == 13 ) {
                        for ( $i = 0; $i < 12; $i++ ) {
                                if ( $isbn[$i] === 'X' ) {
                                        return false;
                                } elseif ( $i % 2 == 0 ) {
                                        $sum += $isbn[$i];
                                } else {
                                        $sum += 3 * $isbn[$i];
                                }
                        }

                        $check = ( 10 - ( $sum % 10 ) ) % 10;
                        if ( (string)$check === $isbn[12] ) {
                                return true;
                        }
                } elseif ( strlen( $isbn ) == 10 ) {
                        for ( $i = 0; $i < 9; $i++ ) {
                                if ( $isbn[$i] === 'X' ) {
                                        return false;
                                }
                                $sum += $isbn[$i] * ( $i + 1 );
                        }

                        $check = $sum % 11;
                        if ( $check == 10 ) {
                                $check = "X";
                        }
                        if ( (string)$check === $isbn[9] ) {
                                return true;
                        }
                }

                return false;
        }

        /**
         * Trim ISBN and remove characters which aren't required
         *
         * @param string $isbn Unclean ISBN
         * @return string
         */
        private static function cleanIsbn( $isbn ) {
                return trim( preg_replace( '![^0-9X]!', '', $isbn ) );
        }

        /**
         * Generate a form to allow users to enter an ISBN
         *
         * @param string $isbn
         */
        private function buildForm( $isbn ) {
                $formDescriptor = [
                        'isbn' => [
                                'type' => 'text',
                                'name' => 'isbn',
                                'label-message' => 'booksources-isbn',
                                'default' => $isbn,
                                'autofocus' => true,
                                'required' => true,
                        ],
                ];

                $context = new DerivativeContext( $this->getContext() );
                $context->setTitle( $this->getPageTitle() );
                HTMLForm::factory( 'ooui', $formDescriptor, $context )
                        ->setWrapperLegendMsg( 'booksources-search-legend' )
                        ->setSubmitTextMsg( 'booksources-search' )
                        ->setMethod( 'get' )
                        ->prepareForm()
                        ->displayForm( false );
        }

        /**
         * Determine where to get the list of book sources from,
         * format and output them
         *
         * @param string $isbn
         * @throws MWException
         * @return bool
         */
        private function showList( $isbn ) {
                $out = $this->getOutput();

                global $wgContLang;

                $isbn = self::cleanIsbn( $isbn );
                # Hook to allow extensions to insert additional HTML,
                # e.g. for API-interacting plugins and so on
                Hooks::run( 'BookInformation', [ $isbn, $out ] );

                # Check for a local page such as Project:Book_sources and use that if available
                $page = $this->msg( 'booksources' )->inContentLanguage()->text();
                $title = Title::makeTitleSafe( NS_PROJECT, $page ); # Show list in content language
                if ( is_object( $title ) && $title->exists() ) {
                        $rev = Revision::newFromTitle( $title, false, Revision::READ_NORMAL );
                        $content = $rev->getContent();

                        if ( $content instanceof TextContent ) {
                                // XXX: in the future, this could be stored as structured data, defining a list of book sources

                                $text = $content->getNativeData();
                                $out->addWikiText( str_replace( 'MAGICNUMBER', $isbn, $text ) );

                                return true;
                        } else {
                                throw new MWException( "Unexpected content type for book sources: " . $content->getModel() );
                        }
                }

                # Fall back to the defaults given in the language file
                $out->addWikiMsg( 'booksources-text' );
                $out->addHTML( '<ul>' );
                $items = $wgContLang->getBookstoreList();
                foreach ( $items as $label => $url ) {
                        $out->addHTML( $this->makeListItem( $isbn, $label, $url ) );
                }
                $out->addHTML( '</ul>' );

                return true;
        }

        /**
         * Format a book source list item
         *
         * @param string $isbn
         * @param string $label Book source label
         * @param string $url Book source URL
         * @return string
         */
        private function makeListItem( $isbn, $label, $url ) {
                $url = str_replace( '$1', $isbn, $url );

                return Html::rawElement( 'li', [],
                        Html::element( 'a', [ 'href' => $url, 'class' => 'external' ], $label )
                );
        }

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