RegexParserFunctions.php

<?php
/*
 * RegexParserFunctions.php - Allows regular expression search and replace within a string
 * @author Jim R. Wilson, Vitaliy Filippov
 * @version 2015-10-22
 * @copyright Copyright (c) 2007 Jim R. Wilson, (c) 2011+ Vitaliy Filippov
 * @license The MIT License - http://www.opensource.org/licenses/mit-license.php
 * -----------------------------------------------------------------------
 * Description:
 *     This is a MediaWiki extension which adds a parser function for performing
 *     regular expression searches and replacements.
 * Requirements:
 *     MediaWiki 1.16.x or higher
 * Installation:
 *     1. Drop this script (RegexParserFunctions.php) in $IP/extensions
 *         Note: $IP is your MediaWiki install dir.
 *     2. Enable the extension by adding this line to your LocalSettings.php:
 *         require_once('extensions/RegexParserFunctions.php');
 * -----------------------------------------------------------------------
 * Copyright (c) 2007 Jim R. Wilson
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights to
 * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
 * the Software, and to permit persons to whom the Software is furnished to do
 * so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in all
 * copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
 * OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
 * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
 * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
 * OTHER DEALINGS IN THE SOFTWARE.
 * -----------------------------------------------------------------------
 */

# Confirm MW environment
if ( !defined( 'MEDIAWIKI' ) ) {
	die( "Not in MediaWiki environment" );
}

# Credits
$wgExtensionCredits['parserhook'][] = [
	'name' => 'RegexParserFunctions',
	'author' => 'Jim R. Wilson (wilson.jim.r<at>gmail.com), Vitaliy Filippov (vitalif<at>mail.ru)',
	'url' => 'http://wiki.4intra.net/RegexParserFunctions',
	'description' => 'Adds a parser function for search and replace using regular expressions.',
	'version' => '2015-12-02',
];

$wgHooks['ParserFirstCallInit'][] = 'RegexParserFunctions::initParser';
$wgExtensionMessagesFiles['RegexParserFunctions'] = __DIR__ . '/RegexParserFunctions.i18n.php';
$wgExtensionMessagesFiles['RegexParserFunctionsMagic'] =
	__DIR__ . '/RegexParserFunctions.i18n.magic.php';

/**
 * Wrapper class for encapsulating Regexp related parser methods
 */
class RegexParserFunctions {
	/**
	 * Performs regular expression search or replacement.
	 *
	 * @param Parser $parser Instance of running Parser.
	 * @param String $subject Input string to evaluate.
	 * @param String $pattern Regular expression pattern - must use /, | or % delimiter
	 * @param String $replacement Regular expression replacement.
	 * @return String Result of replacing pattern with replacement in string, or matching text if replacement was omitted.
	 */
	static function regexParserFunction(
		$parser, $subject = null, $pattern = null, $replacement = null
	) {
		if ( $subject === null || $pattern === null ) {
			return '';
		}
		$acceptable = '/^([\\/\\|%])[^\0]*\\1[imsu]*$/s';
		if ( !preg_match( $acceptable, $pattern ) ) {
			return wfMsg( 'regexp-unacceptable', $pattern );
		}
		if ( $replacement === null ) {
			return preg_match( $pattern, $subject, $matches ) ? $matches[0] : '';
		} else {
			return preg_replace( $pattern, $replacement, $subject );
		}
	}

	static function urlencodeParserFunction( $parser, $value = '' ) {
		return urlencode( $value );
	}

	static function evalParserFunction( $parser ) {
		$args = func_get_args();
		array_shift( $args );
		$args = '{{' . implode( '|', $args ) . '}}';

		return $parser->replaceVariables( $args );
	}

	/**
	 * Sets up parser functions
	 */
	static function initParser( $parser ) {
		$parser->setFunctionHook( 'regex', __CLASS__ . '::regexParserFunction' );
		$parser->setFunctionHook( 'regexp', __CLASS__ . '::regexParserFunction' );
		$parser->setFunctionHook( 'urlencode', __CLASS__ . '::urlencodeParserFunction' );
		$parser->setFunctionHook( 'eval', __CLASS__ . '::evalParserFunction' );

		return true;
	}
}