User:Paxed/ReplaceCharsBlock

ReplaceCharsBlock extension.

NOTE: Still experimental, DO NOT USE!

Adds a <replacecharsblock> -tag, which allows replacing characters in the block with other characters or strings, per char. Replacements are defined first, and the block of text that will be replaced after an empty line.

TODO:

• Allow multiple replacement definitions for same char; use the replacements in the order they're defined, looping.
  • Maybe also in random order, though that'll invalidate cache.

<replacecharsblock> b=foo abcb </replacecharsblock>

afoocfoo

• default as a replacement: used for any characters that don't have explicitly defined replacement. $1 in the replacement will be substituted with the character which is being replaced.
• newline as a replacement: each newline character will be replaced with this.

For example:

Code for ReplaceCharsBlock.php

<?php
/**
 * ReplaceCharsBlock -- replace chars in a block with strings.
 *
 */
 
if( !defined( 'MEDIAWIKI' ) ) {
	die( "This is not a valid entry point to MediaWiki.\n" );
}
 
$wgHooks['ParserFirstCallInit'][] = 'wfReplaceCharsBlock';
 
$wgExtensionCredits['parserhook'][] = array(
	'name' => 'ReplaceCharsBlock',
	'version' => '0.2devel',
	'author' => array(
		'[http://nethackwiki.com/wiki/User:Paxed Pasi Kallinen]',
		'[http://nethackwiki.com/wiki/User:Ilmari_Karonen Ilmari Karonen]',
	),
	'url' => 'http://nethackwiki.com/wiki/User:Paxed/ReplaceCharsBlock',
	'description' => 'Replace characters in a block of text with strings.',
);
 
function wfReplaceCharsBlock( &$parser ) {
	$parser->setHook( 'replacecharsblock', 'renderCharReplacement' );
	return true;
}
 
function renderCharReplacement( $input, $argv, $parser ) {
	/*$parser->disableCache();*/
 
	list( $defs, $text ) = preg_split( '/\n\s*\n/', $input, 2 );
	if ( !isset( $text ) ) {
		$text = $defs;
		$defs = "";
	}
 
	$reps = array();
	$default = false;
	if ( isset( $argv['newlines'] ) ) {
		if ( intval( $argv['newlines'] ) == 1 ) {
			$reps["\n"] = "<br>";
		} else {
			$reps["\n"] = $argv['newlines'];
		}
	}
 
	$defs = explode( "\n", $defs );
	foreach ( $defs as $i => $line ) {
		if ( !preg_match( '/\S/u', $line ) ) {
			continue;
		}
		if ( !preg_match( '/^(\X|default)=(.+)$/u', $line, $match ) ) {
			return "<strong class='error'>Replacecharsblock error on line $i: invalid definition " . htmlspecialchars( $line ) . "</strong>";
		}
		// wfDebug( __METHOD__ . ": mapping $match[1] to $match[2]\n" );
		if ( $match[1] === 'default' ) {
			$default = $match[2];
		} else {
			$reps[ $match[1] ] = $match[2];
		}
	}
 
	if ( $default !== false ) {
		preg_match_all( '/(?>[^\\pM\\pC]\\pM*)/u', $text, $chars );
		$chars = array_diff( array_unique( $chars[0] ), array_keys( $reps ) );
		foreach ( $chars as $char ) {
			$reps[$char] = str_replace( '$1', $char, $default );
			// wfDebug( __METHOD__ . ": adding default map from $char to $reps[$char]\n" );
		}
	}
 
	$text = strtr( $text, $reps ); 
	return $parser->recursiveTagParse( $text );
}