Export Products to CSV: Characteristics Issue

<?php
/**
 * @package    HikaShop for Joomla!
 * @version    1.5.9
 * @author    hikashop.com
 * @copyright  (C) 2010-2012 HIKARI SOFTWARE. All rights reserved.
 * @license    GNU/GPLv3 http://www.gnu.org/licenses/gpl-3.0.html
 */
defined('_JEXEC') or die('Restricted access');
?>
<?php
ob_end_clean();
if(ob_get_level()>2) ob_end_clean();
ob_start();
$eol= "\r\n";
$characteristic = hikashop_get('class.characteristic');
$characteristic->loadConversionTables($this);
$config =& hikashop_config();
$separator = $config->get('csv_separator',";");
$db =& JFactory::getDBO();
$columnsTable = $db->getTableFields(hikashop_table('product'));
$columnsArray = reset($columnsTable);
$columns = $products_columns = array_keys($columnsArray);
$product_table_count = count($columns);
$columns['parent_category']='parent_category';
$columns['categories_image']='categories_image';
$columns['categories']='categories';
$columns['price_value']='price_value';
$columns['price_currency_id']='price_currency_id';
$columns['price_min_quantity']='price_min_quantity';
$columns['price_access']='price_access';
$columns['files']='files';
$columns['images']='images';
$columns['related']='related';
$columns['options']='options';
$characteristicsColumns = array();
if(!empty($this->characteristics)){
  foreach($this->characteristics as $characteristic){
    if(empty($characteristic->characteristic_parent_id)){
      $columns[$characteristic->characteristic_alias]=$characteristic->characteristic_alias;
      $characteristicsColumns[]=$characteristic->characteristic_alias;
    }
  }
}
$after_category_count = count($columns)-($product_table_count+3);
$output='';
foreach($columns as $column){
  if(!empty($column)){
    $output.= '"'.str_replace('"','\\'.'"',$column).'"';
  }
  $output.= $separator;
}
echo rtrim($output,$separator).$eol;
$output='';
if(!empty($this->categories)){
  foreach($this->categories as $category){
    echo '"'.str_repeat('"'.$separator.'"',$product_table_count-1).'"'.$separator;
    if(!empty($category->category_parent_id) && isset($this->categories[$category->category_parent_id])){
      echo '"'.str_replace('"','""',$this->categories[$category->category_parent_id]->category_name).'"'.$separator;
    }else{
      echo '""'.$separator;
    }
    if(!empty($category->file_path)){
      echo '"'.str_replace('"','""',$category->file_path).'"'.$separator;
    }else{
      echo '""'.$separator;
    }
    echo '"'.str_replace('"','""',$category->category_name).'"'.$separator.'"'.str_repeat('"'.$separator.'"',$after_category_count-1).'"'.$eol;
  }
}
if(!empty($this->products)){
  foreach($this->products as $k => $product){
    if($product->product_type=="variant"){
      $this->products[$k]->product_parent_id = str_replace('"','""',$this->products[$product->product_parent_id]->product_code);
    }
  }
  foreach($this->products as $product){
    foreach($products_columns as $column){
      echo '"'.str_replace('"','""',$product->$column).'"'.$separator;
    }
    $categories = array();
    if(!empty($product->categories)){
      foreach($product->categories as $category){
        if(!empty($this->categories[$category])){
          $categories[]=str_replace(array('"',',',';'),array('""','\\,','\\;'),$this->categories[$category]->category_name);
        }
      }
    }
    echo '""'.$separator.'""'.$separator;
    if(!empty($categories)){
      echo '"'.implode($separator,$categories).'"'.$separator;
    }else{
      echo '""'.$separator;
    }
    $values = array();
    $codes = array();
    $qtys = array();
    $accesses = array();
    if(!empty($product->prices)){
      foreach($product->prices as $price){
        $values[]=$price->price_value;
        $codes[]=$this->currencies[$price->price_currency_id]->currency_code;
        $qtys[]=$price->price_min_quantity;
        $accesses[]=$price->price_access;
      }
    }
    if(empty($values)){
      echo '""'.$separator.'""'.$separator.'""'.$separator.'""'.$separator;
    }else{
      echo '"'.implode('|',$values).'"'.$separator.'"'.implode('|',$codes).'"'.$separator.'"'.implode('|',$qtys).'"'.$separator.'"'.implode('|',$accesses).'"'.$separator;
    }
    $files = array();
    if(!empty($product->files)){
      foreach($product->files as $file){
        $files[]=str_replace(array('"',',',';'),array('""','\\,','\\;'),$file->file_path);
      }
    }
    if(empty($files)){
      echo '""'.$separator;
    }else{
      echo '"'.implode($separator,$files).'"'.$separator;
    }
    $images = array();
    if(!empty($product->images)){
      foreach($product->images as $image){
        $images[]=str_replace(array('"',',',';'),array('""','\\,','\\;'),$image->file_path);
      }
    }
    if(empty($images)){
      echo '""'.$separator;
    }else{
      echo '"'.implode($separator,$images).'"'.$separator;
    }
    $related = array();
    if(!empty($product->related)){
      foreach($product->related as $rel){
        $related[]=str_replace(array('"',',',';'),array('""','\\,','\\;'),@$this->products[$rel]->product_code);
      }
    }
    if(empty($related)){
      echo '""'.$separator;
    }else{
      echo '"'.implode($separator,$related).'"'.$separator;
    }
    $options = array();
    if(!empty($product->options)){
      foreach($product->options as $rel){
        $options[]=str_replace(array('"',',',';'),array('""','\\,','\\;'),@$this->products[$rel]->product_code);
      }
    }
    if(empty($options)){
      echo '""';
    }else{
      echo '"'.implode($separator,$options).'"';
    }
    if(!empty($product->variant_links)){
      echo $separator;
      $characteristics=array();
      if(!empty($characteristicsColumns)){
        foreach($product->variant_links as $char_id){
          if(!empty($this->characteristics[$char_id])){
            $char = $this->characteristics[$char_id];
            if(!empty($this->characteristics[$char->characteristic_parent_id])){
              $key = $this->characteristics[$char->characteristic_parent_id]->characteristic_alias;
              $characteristics[$key] = str_replace('"','""',$char->characteristic_value);
            }
          }
        }
        $chars = array();
        foreach($characteristicsColumns as $characteristic){
          $chars[] = '"'.@$characteristics[$characteristic].'"';
        }
        echo implode($separator,$chars);
      }
    }elseif(!empty($characteristicsColumns)){
      echo $separator;
      echo str_repeat('""'.$separator,count($characteristicsColumns)-1).'""';
    }
    echo $eol;
  }
}
$data = ob_get_clean();
header("Pragma: public");
header("Expires: 0"); // set expiration time
header("Cache-Control: must-revalidate, post-check=0, pre-check=0");
header("Content-Type: application/force-download");
header("Content-Type: application/octet-stream");
header("Content-Type: application/download");
header("Content-Disposition: attachment; filename=hikashopexport.csv;");
header("Content-Transfer-Encoding: binary");
header('Content-Length: '.strlen($data));
echo $data;
exit;