* @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 string $isbn ISBN passed as a subpage parameter
*/
public function execute( $isbn ) {
$this->setHeaders();
$this->outputHeader();
$this->isbn = self::cleanIsbn( $isbn ? $isbn : $this->getRequest()->getText( 'isbn' ) );
$this->getOutput()->addHTML( $this->makeForm() );
if( strlen( $this->isbn ) > 0 ) {
if( !self::isValidISBN( $this->isbn ) ) {
$this->getOutput()->wrapWikiMsg( "
\n$1\n
", 'booksources-invalid-isbn' );
}
$this->showList();
}
}
/**
* Returns whether a given ISBN (10 or 13) is valid. True indicates validity.
* @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( $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 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
*
* @return string
*/
private function makeForm() {
global $wgScript;
$form = '';
return $form;
}
/**
* Determine where to get the list of book sources from,
* format and output them
*
* @throws MWException
* @return string
*/
private function showList() {
global $wgContLang;
# Hook to allow extensions to insert additional HTML,
# e.g. for API-interacting plugins and so on
wfRunHooks( 'BookInformation', array( $this->isbn, $this->getOutput() ) );
# 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();
$this->getOutput()->addWikiText( str_replace( 'MAGICNUMBER', $this->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
$this->getOutput()->addWikiMsg( 'booksources-text' );
$this->getOutput()->addHTML( '