Modify document output after caching?

<?php
/*
Title:      Language
Author:     Mark Croxton, [email protected]
Desc:		Plugin triggered OnParseDocument
Updated:    May 15 2009
*/
global $modx;
$domains  = array(
	'de' => array('Deutsch','de.mydomain.com','ltr'),
	'en' => array('English','mydomain.com','ltr'),
	'es' => array('Español','es.mydomain.com','ltr'),
	'fr' => array('Français','fr.mydomain.com','ltr'),
	'zh' => array('中文','cn.mydomain.com','ltr')
	);

// what's the URI of the current page?
$url = $_SERVER['REQUEST_URI'];

# what's the name of the server?
$server = $domains['en'][1]; // English by default
$language = 'en';

# check that the server name is in the predefined array before assigning it 
# to prevent injection via headers
foreach ($domains as $key => $value) {
	if ($value[1] == $_SERVER['SERVER_NAME']) {
		$server = $value[1];
		$language = $key;
	}
}

if ($server != $_SERVER['SERVER_NAME']) {
	// domain not recognised, redirect to default
	$modx->sendRedirect('http://'.$server.$url);
}	
$GLOBALS['domains'] = $domains;
$GLOBALS['language'] = $language;

?>

<?php
/*
Title:      Language switcher
Author:     Mark Croxton, [email protected]
Desc:		Plugin triggered OnWebPagePrerender
			Sets language placeholders based on site url
Updated:    May 15 2009
*/

global $modx, $domains, $language;

# server
$server = 'http://'.$domains[$language][1];
# text direction
$dir = $domains[$language][2];
# what's the URI of the current page?
$url = $_SERVER['REQUEST_URI'];

$tplRow = '
<li[+active+]><a href="[+server+][+url+]"><em>[+lang+] ([+lang.code+])</em></a></li>
';
$tplOuter ='
<ul>
	[+rows+]
</ul>
';

$rows ='';
foreach ($domains as $key => $value) {
	$active='';
	if ($key == $language) {
		$active =' class="active"';
	}
	$f	= array('[+active+]','[+server+]','[+url+]','[+lang+]','[+lang.code+]');
	$v	= array($active,'http://'.$domains[$key][1],$url,$domains[$key][0],$key);
	$rows.= str_replace($f,$v,$tplRow);
}

$switcher = str_replace('[+rows+]',$rows,$tplOuter);

# replace placeholders using a custom syntax to ensure these values are never cached ((placeholder))
$fields = array('((base.href))','((dir))','((lang))','((language))','((lang.switcher))');
$values = array($server, $dir, $language, $domains[$language][0], $switcher);
$modx->documentOutput = str_replace($fields,$values,$modx->documentOutput);

?>

<?php

/*
Title:      Translate
Author:     Mark Croxton, [email protected]
Desc:		Translates a document field, tv, or chunk, into the global language
Updated:    May 18 2009
*/

global $modx, $language;

$field = isset($field)? $field : 'pagetitle';
$tpl = isset($tpl)? $tpl : '';
$word = isset($word)? $word : '';
$docid = isset($id)? $id : $modx->documentIdentifier;

if ($word != '') {
	$lexicon = array(
		'Members' => array(
			'en' => 'Members',
			'de' => 'Mitglieder',
			'es' => 'Miembros',
			'fr' => 'Membres',
			'zh' => '会员'
		),
		'Map' => array(
			'en' => 'Map',
			'de' => 'Karte',
			'es' => 'Mapa',
			'fr' => 'Cartes',
			'zh' => '地图'
		),
		'Search' => array(
			'en' => 'Search',
			'de' => 'Suche',
			'es' => 'Buscar',
			'fr' => 'Trouver',
			'zh' => '搜索'
		),
		'News' => array(
			'en' => 'News',
			'de' => 'News',
			'es' => 'Noticias',
			'fr' => 'Nouvelle',
			'zh' => '新闻'
		),
		'Press releases' => array(
			'en' => 'Press releases',
			'de' => 'Artikel',
			'es' => 'Noticias',
			'fr' => 'Articles',
			'zh' => '新闻稿件'
		),
		'Find press releases' => array(
			'en' => 'Press releases',
			'de' => 'Pressemitteilungen finden',
			'es' => 'Buscador de comunicados de prensa',
			'fr' => 'Trouver des communiqués',
			'zh' => '查找新闻稿件'
		),
		'Events' => array(
			'en' => 'Events',
			'de' => 'Events',
			'es' => 'Eventos',
			'fr' => 'Événements',
			'zh' => '活动'
		),
		'Login' => array(
			'en' => 'Login',
			'de' => '',
			'es' => '',
			'fr' => '',
			'zh' => ''
		),
		'Contact' => array(
			'en' => 'Contact',
			'de' => '',
			'es' => '',
			'fr' => '',
			'zh' => ''
		),
		'Profile' => array(
			'en' => 'Profile',
			'de' => 'Profil',
			'es' => 'Perfil',
			'fr' => 'Profil',
			'zh' => '外形'
		),
		'Other offices' => array(
			'en' => 'Other offices',
			'de' => 'Andere Büros',
			'es' => 'Otras oficinas',
			'fr' => 'D\'autres bureaux',
			'zh' => '其他办公室'
		),
		'Key contact' => array(
			'en' => 'Key contact',
			'de' => 'Hauptkontakt',
			'es' => 'Contacto principal',
			'fr' => 'Contact principal',
			'zh' => '主要联络'
		),
		'Firm name' => array(
			'en' => 'Firm name',
			'de' => 'Firmenname',
			'es' => 'Nombre de la empresa',
			'fr' => 'Nom de la firme',
			'zh' => '事务所名称'
		),
		'City' => array(
			'en' => 'City',
			'de' => 'Stadt',
			'es' => 'Ciudad',
			'fr' => 'Ville',
			'zh' => '城市'
		),
		'Country' => array(
			'en' => 'Country',
			'de' => 'Land',
			'es' => 'País',
			'fr' => 'Pays',
			'zh' => '国家'
		),
		'A-Z' => array(
			'en' => 'A-Z',
			'de' => 'A-Z',
			'es' => 'A-Z',
			'fr' => 'A-Z',
			'zh' => '字母'
		)
	);
	return $lexicon[$word][$language];
} else if ($tpl=='') {
	$lang_field = $field;
	if ($language != 'en') { // ignore english
		$lang_field = $field.$language;
	}

	$docfield = $modx->getTemplateVarOutput(array($lang_field), $docid, 1);

	if ($docfield[$lang_field] == '') { // no content for the selected language, so use english
		$docfield = $modx->getTemplateVarOutput(array($field), $docid, 1);
		return $docfield[$field];
	} else {
		return $docfield[$lang_field];
	}
} else {
	// eg myChunk_en, myChunk_de etc
	return $modx->getChunk($tpl.'_'.$language);
}

?>