Rewrite URLs in Wordpress

gistfile1.aw

<?php
/*
Plugin Name: ReWrite
Plugin URI: http://nelm.io/
Description: A Plugin to ReWrite URLs.
Version: 0.1
Author: Pierre Spring
Author URI: http://nelm.io/pierre
License: GPL2
*/

/*  Copyright 2011  Pierre Spring  (email : pierre@nelm.io)

    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License, version 2, as
    published by the Free Software Foundation.

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with this program; if not, write to the Free Software
    Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
*/


class ReWrite
{
    public static $lang;
    public static $pageId;

    public static function hookActivate()
    {
        // flushes the modrewrite rules when
        // activating the plugin
        global $wp_rewrite;
        $wp_rewrite->flush_rules();
    }

    public static function hookDeactivate()
    {
    }
    
    public function modRewrite($rules)
    {
        $home_root = parse_url(home_url());
        if ( isset( $home_root['path'] ) ) {
            $home_root = trailingslashit($home_root['path']);
        } else {
            $home_root = '/';
        }
        
        $ReWrite_rules = array(
            '',
            '# ReWrite Plugin: Begin Custom htaccess',
            '<IfModule mod_rewrite.c>',
            'RewriteEngine On',
            'RewriteBase ' . $home_root,
            'RewriteCond %{REQUEST_URI} ^/$',
            'RewriteRule (.*) /de/$1 [R=301,L]',
            '',
            'RewriteCond %{REQUEST_URI} ^/(\w{2})/news/?$',
            'RewriteRule .* /category/%1/ [L]',
            '</IfModule>',
            '# ReWrite Plugin: End Custom htaccess',
            '', ''
        );
        
        #RewriteCond %{REQUEST_URI} ^/\w{2}/blog
        #RewriteRule (.*) /category/de/

        #RewriteCond %{REQUEST_URI} ^/\w{2}/\d{4}
        #RewriteRule /\w{2}(.*) /$1
        
        $ReWrite_rules = implode("\n", $ReWrite_rules);
        return $ReWrite_rules . $rules;
        
    }

    public static function actionInit()
    {
        // die(var_dump($_SERVER['REDIRECT_URL']));
        // parse url
        $baseDir = strtr(dirname($_SERVER['SCRIPT_NAME']), '\\', '/');
        $path_array = explode('/', trim(substr($_SERVER['REQUEST_URI'], strlen($baseDir)), '/'));

        // extract language if present
        if (in_array(reset($path_array), array('de', 'en'), true)) {
            self::$lang = array_shift($path_array);
            // TODO WP_LANG should be defined accordingly in wp-config.php
        }

        // leftovers = page id
        self::$pageId = implode('/', $path_array);

        // Wordpress only look out for REQUEST_URI, and never for REDIRECT_URL.
        // As we make extensive usage of rewrite rules, this has to be fixed here.
        // c.f. http://core.trac.wordpress.org/ticket/15478
        if (isset($_SERVER['REDIRECT_URL']) && $_SERVER['REDIRECT_URL']) {
            $_SERVER['REQUEST_URI'] = $_SERVER['REDIRECT_URL'];
        }
    }
    

}

register_activation_hook(__FILE__, array('ReWrite', 'hookActivate'));
register_deactivation_hook(__FILE__, array('ReWrite', 'hookDeactivate'));

add_action('init', array('ReWrite', 'actionInit'));

add_filter('mod_rewrite_rules', array('ReWrite', 'modRewrite'));