OpenCart - SEO URLs

<?php
//opencart SEO Urls - SQL INSERT: http://pastebin.com/vA7n5KKK

class ControllerCommonSeoUrl extends Controller {
   public function index() {
      // Add rewrite to url class
      if ($this->config->get('config_seo_url')) {
         $this->url->addRewrite($this);
      }

      // Decode URL
      if (isset($this->request->get['_route_'])) {
         $parts = explode('/', $this->request->get['_route_']);

         $route = "";

         foreach ($parts as $part) {
            $query = $this->db->query("SELECT * FROM " . DB_PREFIX . "url_alias WHERE keyword = '" . $this->db->escape($part) . "'");

            if ($query->num_rows) {
               $url = explode('=', $query->row['query']);

               if(count($url) > 1){

               if ($url[0] == 'product_id') {
                  $this->request->get['product_id'] = $url[1];
               }

               if ($url[0] == 'category_id') {
                  if (!isset($this->request->get['path'])) {
                     $this->request->get['path'] = $url[1];
                  } else {
                     $this->request->get['path'] .= '_' . $url[1];
                  }
               }

               if ($url[0] == 'manufacturer_id') {
                  $this->request->get['manufacturer_id'] = $url[1];
               }

               if ($url[0] == 'information_id') {
                  $this->request->get['information_id'] = $url[1];
               }
               }else{
                  $route = $url[0];
               }
            } else {
               $this->request->get['route'] = 'error/not_found';
            }
         }

         if (isset($this->request->get['product_id'])) {
            $this->request->get['route'] = 'product/product';
         } elseif (isset($this->request->get['path'])) {
            $this->request->get['route'] = 'product/category';
         } elseif (isset($this->request->get['manufacturer_id'])) {
            $this->request->get['route'] = 'product/manufacturer/product';
         } elseif (isset($this->request->get['information_id'])) {
            $this->request->get['route'] = 'information/information';
         }else {
            $this->request->get['route'] = $route;
         }


         if (isset($this->request->get['route'])) {
            return $this->forward($this->request->get['route']);
         }
      }
   }

   public function rewrite($link) {
      if ($this->config->get('config_seo_url')) {
         $url_data = parse_url(str_replace('&amp;', '&', $link));

         $url = '';

         $data = array();

         parse_str($url_data['query'], $data);

         foreach ($data as $key => $value) {
            if (($key == 'product_id') || ($key == 'manufacturer_id') || ($key == 'information_id')) {
               $query = $this->db->query("SELECT * FROM " . DB_PREFIX . "url_alias WHERE `query` = '" . $this->db->escape($key . '=' . (int)$value) . "'");

               if ($query->num_rows) {
                  $url .= '/' . $query->row['keyword'];

                  unset($data[$key]);
               }
            } elseif ($key == 'path') {
               $categories = explode('_', $value);

               foreach ($categories as $category) {
                  $query = $this->db->query("SELECT * FROM " . DB_PREFIX . "url_alias WHERE `query` = 'category_id=" . (int)$category . "'");

                  if ($query->num_rows) {
                     $url .= '/' . $query->row['keyword'];
                  }
               }

               unset($data[$key]);
            }elseif ($key == 'route') {
               $query = $this->db->query("SELECT * FROM " . DB_PREFIX . "url_alias WHERE `query` = '" . $this->db->escape($value) . "'");

               if ($query->num_rows) {
                  $url .= '/' . $query->row['keyword'];

                  unset($data[$key]);
               }
            }
         }

         if ($url) {
            unset($data['route']);

            $query = '';

            if ($data) {
               foreach ($data as $key => $value) {
                  $query .= '&' . $key . '=' . $value;
               }

               if ($query) {
                  $query = '?' . trim($query, '&');
               }
            }

            return $url_data['scheme'] . '://' . $url_data['host'] . (isset($url_data['port']) ? ':' . $url_data['port'] : '') . str_replace('/index.php', '', $url_data['path']) . $url . $query;
         } else {
            return $link;
         }
      } else {
         return $link;
      }
   }
}
?>