includes/specials/SpecialBooksources.php

   1 <?php
   2 /**
   3  * Implements Special:Booksources
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation; either version 2 of the License, or
   8  * (at your option) any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License along
  16  * with this program; if not, write to the Free Software Foundation, Inc.,
  17  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  18  * http://www.gnu.org/copyleft/gpl.html
  19  *
  20  * @file
  21  * @ingroup SpecialPage
  22  */
  23
  24 /**
  25  * Special page outputs information on sourcing a book with a particular ISBN
  26  * The parser creates links to this page when dealing with ISBNs in wikitext
  27  *
  28  * @author Rob Church <robchur@gmail.com>
  29  * @ingroup SpecialPage
  30  */
  31 class SpecialBookSources extends SpecialPage {
  32         /**
  33          * ISBN passed to the page, if any
  34          */
  35         private $isbn = '';
  36
  37         /**
  38          * Constructor
  39          */
  40         public function __construct() {
  41                 parent::__construct( 'Booksources' );
  42         }
  43
  44         /**
  45          * Show the special page
  46          *
  47          * @param string $isbn ISBN passed as a subpage parameter
  48          */
  49         public function execute( $isbn ) {
  50                 $this->setHeaders();
  51                 $this->outputHeader();
  52                 $this->isbn = self::cleanIsbn( $isbn ? $isbn : $this->getRequest()->getText( 'isbn' ) );
  53                 $this->getOutput()->addHTML( $this->makeForm() );
  54                 if ( strlen( $this->isbn ) > 0 ) {
  55                         if ( !self::isValidISBN( $this->isbn ) ) {
  56                                 $this->getOutput()->wrapWikiMsg(
  57                                         "<div class=\"error\">\n$1\n</div>",
  58                                         'booksources-invalid-isbn'
  59                                 );
  60                         }
  61                         $this->showList();
  62                 }
  63         }
  64
  65         /**
  66          * Returns whether a given ISBN (10 or 13) is valid. True indicates validity.
  67          * @param string $isbn ISBN passed for check
  68          * @return bool
  69          */
  70         public static function isValidISBN( $isbn ) {
  71                 $isbn = self::cleanIsbn( $isbn );
  72                 $sum = 0;
  73                 if ( strlen( $isbn ) == 13 ) {
  74                         for ( $i = 0; $i < 12; $i++ ) {
  75                                 if ( $isbn[$i] === 'X' ) {
  76                                         return false;
  77                                 } elseif ( $i % 2 == 0 ) {
  78                                         $sum += $isbn[$i];
  79                                 } else {
  80                                         $sum += 3 * $isbn[$i];
  81                                 }
  82                         }
  83
  84                         $check = ( 10 - ( $sum % 10 ) ) % 10;
  85                         if ( (string)$check === $isbn[12] ) {
  86                                 return true;
  87                         }
  88                 } elseif ( strlen( $isbn ) == 10 ) {
  89                         for ( $i = 0; $i < 9; $i++ ) {
  90                                 if ( $isbn[$i] === 'X' ) {
  91                                         return false;
  92                                 }
  93                                 $sum += $isbn[$i] * ( $i + 1 );
  94                         }
  95
  96                         $check = $sum % 11;
  97                         if ( $check == 10 ) {
  98                                 $check = "X";
  99                         }
 100                         if ( (string)$check === $isbn[9] ) {
 101                                 return true;
 102                         }
 103                 }
 104
 105                 return false;
 106         }
 107
 108         /**
 109          * Trim ISBN and remove characters which aren't required
 110          *
 111          * @param string $isbn Unclean ISBN
 112          * @return string
 113          */
 114         private static function cleanIsbn( $isbn ) {
 115                 return trim( preg_replace( '![^0-9X]!', '', $isbn ) );
 116         }
 117
 118         /**
 119          * Generate a form to allow users to enter an ISBN
 120          *
 121          * @return string
 122          */
 123         private function makeForm() {
 124                 $form = Html::openElement( 'fieldset' ) . "\n";
 125                 $form .= Html::element(
 126                         'legend',
 127                         array(),
 128                         $this->msg( 'booksources-search-legend' )->text()
 129                 ) . "\n";
 130                 $form .= Html::openElement( 'form', array( 'method' => 'get', 'action' => wfScript() ) ) . "\n";
 131                 $form .= Html::hidden( 'title', $this->getPageTitle()->getPrefixedText() ) . "\n";
 132                 $form .= '<p>' . Xml::inputLabel(
 133                         $this->msg( 'booksources-isbn' )->text(),
 134                         'isbn',
 135                         'isbn',
 136                         20,
 137                         $this->isbn,
 138                         array( 'autofocus' => '', 'class' => 'mw-ui-input-inline' )
 139                 );
 140
 141                 $form .= '&#160;' . Html::submitButton(
 142                         $this->msg( 'booksources-search' )->text(),
 143                         array(), array( 'mw-ui-progressive' )
 144                 ) . "</p>\n";
 145
 146                 $form .= Html::closeElement( 'form' ) . "\n";
 147                 $form .= Html::closeElement( 'fieldset' ) . "\n";
 148
 149                 return $form;
 150         }
 151
 152         /**
 153          * Determine where to get the list of book sources from,
 154          * format and output them
 155          *
 156          * @throws MWException
 157          * @return string
 158          */
 159         private function showList() {
 160                 global $wgContLang;
 161
 162                 # Hook to allow extensions to insert additional HTML,
 163                 # e.g. for API-interacting plugins and so on
 164                 Hooks::run( 'BookInformation', array( $this->isbn, $this->getOutput() ) );
 165
 166                 # Check for a local page such as Project:Book_sources and use that if available
 167                 $page = $this->msg( 'booksources' )->inContentLanguage()->text();
 168                 $title = Title::makeTitleSafe( NS_PROJECT, $page ); # Show list in content language
 169                 if ( is_object( $title ) && $title->exists() ) {
 170                         $rev = Revision::newFromTitle( $title, false, Revision::READ_NORMAL );
 171                         $content = $rev->getContent();
 172
 173                         if ( $content instanceof TextContent ) {
 174                                 // XXX: in the future, this could be stored as structured data, defining a list of book sources
 175
 176                                 $text = $content->getNativeData();
 177                                 $this->getOutput()->addWikiText( str_replace( 'MAGICNUMBER', $this->isbn, $text ) );
 178
 179                                 return true;
 180                         } else {
 181                                 throw new MWException( "Unexpected content type for book sources: " . $content->getModel() );
 182                         }
 183                 }
 184
 185                 # Fall back to the defaults given in the language file
 186                 $this->getOutput()->addWikiMsg( 'booksources-text' );
 187                 $this->getOutput()->addHTML( '<ul>' );
 188                 $items = $wgContLang->getBookstoreList();
 189                 foreach ( $items as $label => $url ) {
 190                         $this->getOutput()->addHTML( $this->makeListItem( $label, $url ) );
 191                 }
 192                 $this->getOutput()->addHTML( '</ul>' );
 193
 194                 return true;
 195         }
 196
 197         /**
 198          * Format a book source list item
 199          *
 200          * @param string $label Book source label
 201          * @param string $url Book source URL
 202          * @return string
 203          */
 204         private function makeListItem( $label, $url ) {
 205                 $url = str_replace( '$1', $this->isbn, $url );
 206
 207                 return Html::rawElement( 'li', array(),
 208                         Html::element( 'a', array( 'href' => $url, 'class' => 'external' ), $label ) );
 209         }
 210
 211         protected function getGroupName() {
 212                 return 'wiki';
 213         }
 214 }