<?php

/**
 * File holding the SMWSpecialTypes class for the Special:Types page. 
 *
 * @file SMW_SpecialTypes.php
 * 
 * @ingroup SMWSpecialPage
 * @ingroup SpecialPage
 *
 * @author S Page
 * @author Markus Krötzsch
 * @author Jeroen De Dauw
 */

if ( !defined( 'MEDIAWIKI' ) ) {
	die( 'Not an entry point.' );
}

/**
 * This special page for MediaWiki provides information about types. Type information is 
 * stored in the smw_attributes database table, gathered both from the annotations in
 * articles, and from metadata already some global variables managed by SMWTypeHandlerFactory,
 * and in Type: Wiki pages. This only reports on the Type: Wiki pages.
 * 
 * @ingroup SMWSpecialPage
 * @ingroup SpecialPage
 * 
 * @author S Page
 * @author Markus Krötzsch
 * @author Jeroen De Dauw
 */
class SMWSpecialTypes extends SpecialPage {
	
	public function __construct() {
		parent::__construct( 'Types' );
		smwfLoadExtensionMessages( 'SemanticMediaWiki' );
	}

	public function execute( $param ) {	
		wfProfileIn( 'smwfDoSpecialTypes (SMW)' );
		
		global $wgOut;
		
		$wgOut->setPageTitle( wfMsg( 'types' ) );
		
		$rep = new TypesPage();
		
		list( $limit, $offset ) = wfCheckLimits();
		$rep->doQuery( $offset, $limit );
		
		// Ensure locally collected output data is pushed to the output!
		SMWOutputs::commitToOutputPage( $wgOut );
		
		wfProfileOut( 'smwfDoSpecialTypes (SMW)' );	
	}
	
}

class TypesPage extends QueryPage {

	function getName() {
		return "Types";
	}

	function isExpensive() {
		return false;
	}

	function isSyndicated() {
		return false;
	}

	function getPageHeader() {
		return '<p>' . wfMsg( 'smw_types_docu' ) . "</p><br />\n";
	}

	function getSQL() {
		global $smwgContLang;
		$dbr = wfGetDB( DB_SLAVE );
		$page = $dbr->tableName( 'page' );
		$NStype = SMW_NS_TYPE;
		// TODO: Perhaps use the dbr syntax from SpecialAllpages.
		// NOTE: type, namespace, title and value must all be defined for QueryPage to work (incl. caching)
		$sql = "(SELECT 'Types' as type, {$NStype} as namespace, page_title as title, " .
		        "page_title as value, 1 as count FROM $page WHERE page_namespace = $NStype AND page_is_redirect = '0')";
		// make SQL for built-in datatypes
		foreach ( SMWDataValueFactory::getKnownTypeLabels() as $label ) {
			$label = str_replace( ' ', '_', $label ); // DBkey form so that SQL can elminate duplicates
			$sql .= " UNION (SELECT 'Types' as type,  {$NStype} as namespace, '$label' as title, " .
		            "'$label' as value, 1 as count)";
		}
		return $sql;
	}

	function sortDescending() {
		return false;
	}

	function formatResult( $skin, $result ) {
		return $this->getTypeInfo( $skin, $result->value );
	}

	/**
	 * Returns the info about a type as HTML
	 */
	function getTypeInfo( $skin, $titletext ) {
		$tv = SMWDataValueFactory::newTypeIDValue( '__typ', $titletext );
		$info = array();
		$error = array();
		if ( $tv->isAlias() ) { // print the type title as found, long text would (again) print the alias
			$ttitle = Title::makeTitle( SMW_NS_TYPE, $titletext );
			$link = $skin->makeKnownLinkObj( $ttitle, $ttitle->getText() ); // aliases are only found if the page exists
			$info[] = wfMsg( 'smw_isaliastype', $tv->getLongHTMLText() );
		} else {
			$link = $tv->getLongHTMLText( $skin );
			if ( !$tv->isBuiltIn() ) { // find out whether and how this was user-defined
				$dv = SMWDataValueFactory::newTypeObjectValue( $tv );
				$units = $dv->getUnitList();
				if ( count( $units ) == 0 ) {
					$error[] = wfMsg( 'smw_isnotype', $tv->getLongHTMLText() );
				} else {
					$info[] = wfMsg( 'smw_typeunits', $tv->getLongHTMLText(), implode( ', ', $units ) );
				}
			}
		}
	
		if ( count( $error ) > 0 ) {
			$link .= smwfEncodeMessages( $error );
		}
		if ( count( $info ) > 0 ) {
			$link .= smwfEncodeMessages( $info, 'info' );
		}
		return $link;
	}

}