exchange-2.0/app/Classes/Helpers/InvoiceDocumentsHelper.php

<?php

namespace App\Classes\Helpers;

class InvoiceDocumentsHelper
{
    public static function calculateSubtotal($po_order_transaction, $currencyRate) {
        $subtotal = "0";
        foreach ($po_order_transaction->transactionDetails as $transaction_detail) {
            $unitPrice = bcdiv((string)$transaction_detail->price, (string)$currencyRate, 5);
            $itemTotal = bcmul($unitPrice, (string)$transaction_detail->quantity, 5);
            $subtotal = bcadd($subtotal, $itemTotal, 5);
        }
        return $subtotal;
    }

    public static function getVoucherDiscount($voucher_redemption) {
        return $voucher_redemption ? bcmul((string)$voucher_redemption->value, "-1", 2) : "0";
    }

    public static function roundUp($number, $decimals) {
        $factor = pow(10, $decimals);
        if ($number > 0) {
            return ceil($number * $factor) / $factor;
        } else {
            return floor($number * $factor) / $factor;
        }
    }
}