WooCommerce Checkout Add-ons

// "Checkout Add-ons" plugin
class WOE_Checkout_Addons_Mod {
	var $fields = array('Student Name','Student Grade Lavel','Teacher Name');// edit this line!!
	function __construct() {
		add_filter('woe_get_order_fields', array($this,'add_order_fields') );
		add_action('woe_order_export_started', array($this,'get_fee_details') );
		add_filter('woe_fetch_order_row', array($this,'fill_new_columns'), 10, 2);
	}
	
	function add_order_fields($fields) {
		foreach($this->fields as $pos=>$name) {
			$fields['fee_addon_'.$pos] = array('segment'=>'other','label'=>$name, 'colname'=>$name,'checked'=>1);
		}	
		return $fields;
	}
	
	function get_fee_details($order_id) {
		$this->fee_data = array();
		
		$order = new WC_Order($order_id);
		foreach($order->get_items("fee") as $item_id=>$item) {
			$pos = array_search($item['name'],$this->fields);
			if( $pos  !== false) {
				$item_meta = $order->get_item_meta( $item_id );
				$this->fee_data[$pos] = join(", ", $item_meta['_wc_checkout_add_on_value']); // many values?
			}
		}
		return $order_id; 
	}
	
	// add new values to row
	function fill_new_columns($row,$order_id) {
		foreach($this->fields as $pos=>$name) {
			if(isset($row['fee_addon_'.$pos]) AND isset($this->fee_data[$pos]) )
				$row['fee_addon_'.$pos] = $this->fee_data[$pos] ;
		}		
		return $row;
	}
}
new WOE_Checkout_Addons_Mod();

// "Checkout Add-ons" plugin

class WOE_Checkout_Addons_Mod {

var $fields = array('Student Name','Student Grade Lavel','Teacher Name');// edit this line!!

function __construct() {

add_filter('woe_get_order_fields', array($this,'add_order_fields') );

add_action('woe_order_export_started', array($this,'get_fee_details') );

add_filter('woe_fetch_order_row', array($this,'fill_new_columns'), 10, 2);

}

function add_order_fields($fields) {

foreach($this->fields as $pos=>$name) {

$fields['fee_addon_'.$pos] = array('segment'=>'other','label'=>$name, 'colname'=>$name,'checked'=>1);

}

return $fields;

}

function get_fee_details($order_id) {

$this->fee_data = array();

$order = new WC_Order($order_id);

foreach($order->get_items("fee") as $item_id=>$item) {

$pos = array_search($item['name'],$this->fields);

if( $pos !== false) {

$item_meta = $order->get_item_meta( $item_id );

$this->fee_data[$pos] = join(", ", $item_meta['_wc_checkout_add_on_value']); // many values?

}

return $order_id;

}

// add new values to row

function fill_new_columns($row,$order_id) {

foreach($this->fields as $pos=>$name) {

if(isset($row['fee_addon_'.$pos]) AND isset($this->fee_data[$pos]) )

$row['fee_addon_'.$pos] = $this->fee_data[$pos] ;

}

return $row;

}

new WOE_Checkout_Addons_Mod();