wikimedia/mediawiki-extensions-Wikibase

<?php

namespace Wikibase\Lib\Store;

/**
 * Base class for PropertyOrderProviders, that parse the property order from a
 * wikitext page.
 *
 * @license GPL-2.0-or-later
 * @author Lucie-Aimée Kaffee
 * @author Marius Hoch
 */
abstract class WikiTextPropertyOrderProvider implements PropertyOrderProvider {

    /**
     * @see parent::getPropertyOrder()
     * @return null|int[] null if page doesn't exist
     * @throws PropertyOrderProviderException
     */
    public function getPropertyOrder() {
        $pageContent = $this->getPropertyOrderWikitext();
        if ( $pageContent === null ) {
            return null;
        }
        $parsedList = $this->parseList( $pageContent );

        return array_flip( $parsedList );
    }

    /**
     * Get the wikitext of the property order list.
     *
     * @return string|null
     * @throws PropertyOrderProviderException
     */
    abstract protected function getPropertyOrderWikitext();

    /**
     * @param string $pageContent
     *
     * @return string[]
     */
    private function parseList( $pageContent ) {
        $pageContent = preg_replace( '@<!--.*?-->@s', '', $pageContent );

        preg_match_all(
            '@^[*#]+\h*(?:\[\[(?:d:)?Property:)?(?:{{[a-z]+\|)?(P\d+\b)@im',
            $pageContent,
            $orderedPropertiesMatches,
            PREG_PATTERN_ORDER
        );
        $orderedProperties = array_map( 'strtoupper', $orderedPropertiesMatches[1] );

        return $orderedProperties;
    }

}