custom espresso_update_attendee_payment_status_in_db to work with partial payments

gistfile1.txt

function espresso_update_attendee_payment_status_in_db_custom($payment_data) {
//	echo '<h3>'. __CLASS__ . '->' . __FUNCTION__ . ' <br /><span style="font-size:10px;font-weight:normal;">' . __FILE__ . '<br />line no: ' . __LINE__ . '</span></h3>';
	remove_filter('filter_hook_espresso_update_attendee_payment_data_in_db', 'espresso_update_attendee_payment_status_in_db');
	global $wpdb;
	
	$payment_data['payment_date'] = date(get_option('date_format'));

	if ($payment_data['payment_status'] == "Completed") {
		$payment = $payment_data['total_cost'];
	} elseif($payment_data['payment_status'] == "Pending" && !empty($payment_data['amount_paid'])) {
		$payment_data['amount_pd'] = $payment_data['amount_pd'] + $payment_data['amount_paid'];
		$payment = $payment_data['amount_pd'];
	} else {
		return $payment_data;
	}
	

	$wpdb->update( 
		EVENTS_ATTENDEE_TABLE, 
		array( 'amount_pd' => $payment ), 
		array( 'id' => $payment_data['attendee_id'] ), 
		array( '%f' ),
		array( '%d' ) 
	);

	$payment_data['txn_details'] = empty( $payment_data['txn_details'] ) ? serialize( $_REQUEST ) : $payment_data['txn_details']; 

	$wpdb->update( 
		EVENTS_ATTENDEE_TABLE, 
		array( 
			'payment_status' 		=> $payment_data['payment_status'],
			'txn_type' 					=> $payment_data['txn_type'],
			'txn_id' 						=> $payment_data['txn_id'],
			'payment_date' 		=> $payment_data['payment_date'],
			'transaction_details' 	=> $payment_data['txn_details'],
			'date'=>current_time('mysql')
		), 
		array( 'attendee_session' => $payment_data['attendee_session'] ), 
		array( '%s', '%s', '%s', '%s', '%s','%s' ),
		array( '%s' ) 
	);	
	
	do_action('action_hook_espresso_track_successful_sale',$payment_data);
	
	return $payment_data;
}
add_filter('filter_hook_espresso_update_attendee_payment_data_in_db', 'espresso_update_attendee_payment_status_in_db_custom', 5);