protected function parseIOS6StyleReceipt(): void
    {
        $this->receipt = $this->raw_data['receipt'];
        $this->purchases = [];
        $this->purchases[] = new PurchaseItem($this->raw_data['receipt']);

        if (array_key_exists('bid', $this->raw_data['receipt'])) {
            $this->bundle_id = $this->raw_data['receipt']['bid'];
        }
    }