* @todo Validate ISBNs using the standard check-digit method * @ingroup SpecialPage */ class SpecialBookSources extends SpecialPage { /** * ISBN passed to the page, if any */ private $isbn = ''; /** * Constructor */ public function __construct() { parent::__construct( 'Booksources' ); } /** * Show the special page * * @param $isbn ISBN passed as a subpage parameter */ public function execute( $isbn ) { global $wgOut, $wgRequest; $this->setHeaders(); $this->isbn = self::cleanIsbn( $isbn ? $isbn : $wgRequest->getText( 'isbn' ) ); $wgOut->addWikiMsg( 'booksources-summary' ); $wgOut->addHTML( $this->makeForm() ); if( strlen( $this->isbn ) > 0 ) { if( !self::isValidISBN( $this->isbn ) ) { $wgOut->wrapWikiMsg( "
\n$1\n
", 'booksources-invalid-isbn' ); } $this->showList(); } } /** * Returns whether a given ISBN (10 or 13) is valid. True indicates validity. * @param isbn ISBN passed for check */ public static function isValidISBN( $isbn ) { $isbn = self::cleanIsbn( $isbn ); $sum = 0; if( strlen( $isbn ) == 13 ) { for( $i = 0; $i < 12; $i++ ) { if($i % 2 == 0) { $sum += $isbn{$i}; } else { $sum += 3 * $isbn{$i}; } } $check = (10 - ($sum % 10)) % 10; if ($check == $isbn{12}) { return true; } } elseif( strlen( $isbn ) == 10 ) { for($i = 0; $i < 9; $i++) { $sum += $isbn{$i} * ($i + 1); } $check = $sum % 11; if($check == 10) { $check = "X"; } if($check == $isbn{9}) { return true; } } return false; } /** * Trim ISBN and remove characters which aren't required * * @param $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 * * @return string */ private function makeForm() { global $wgScript; $title = self::getTitleFor( 'Booksources' ); $form = '
' . wfMsgHtml( 'booksources-search-legend' ) . ''; $form .= Xml::openElement( 'form', array( 'method' => 'get', 'action' => $wgScript ) ); $form .= Html::hidden( 'title', $title->getPrefixedText() ); $form .= '

' . Xml::inputLabel( wfMsg( 'booksources-isbn' ), 'isbn', 'isbn', 20, $this->isbn ); $form .= ' ' . Xml::submitButton( wfMsg( 'booksources-go' ) ) . '

'; $form .= Xml::closeElement( 'form' ); $form .= '
'; return $form; } /** * Determine where to get the list of book sources from, * format and output them * * @return string */ private function showList() { global $wgOut, $wgContLang; # Hook to allow extensions to insert additional HTML, # e.g. for API-interacting plugins and so on wfRunHooks( 'BookInformation', array( $this->isbn, &$wgOut ) ); # Check for a local page such as Project:Book_sources and use that if available $title = Title::makeTitleSafe( NS_PROJECT, wfMsgForContent( 'booksources' ) ); # Show list in content language if( is_object( $title ) && $title->exists() ) { $rev = Revision::newFromTitle( $title ); $wgOut->addWikiText( str_replace( 'MAGICNUMBER', $this->isbn, $rev->getText() ) ); return true; } # Fall back to the defaults given in the language file $wgOut->addWikiMsg( 'booksources-text' ); $wgOut->addHTML( '' ); return true; } /** * Format a book source list item * * @param $label Book source label * @param $url Book source URL * @return string */ private function makeListItem( $label, $url ) { $url = str_replace( '$1', $this->isbn, $url ); return '
  • ' . htmlspecialchars( $label ) . '
  • '; } }