* @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 = '';
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( '' );
$items = $wgContLang->getBookstoreList();
foreach( $items as $label => $url )
$wgOut->addHTML( $this->makeListItem( $label, $url ) );
$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 ) . '';
}
}