erpsaas/app/Utilities/Currency/CurrencyConverter.php

<?php

namespace App\Utilities\Currency;

use App\Facades\Forex;
use Filament\Forms\Set;

class CurrencyConverter
{
    public static function convertAndSet($newCurrency, $oldCurrency, $amount): ?string
    {
        if ($newCurrency === null || $oldCurrency === $newCurrency) {
            return null;
        }

        $old_attr = currency($oldCurrency);
        $new_attr = currency($newCurrency);
        $temp_balance = str_replace([$old_attr->getThousandsSeparator(), $old_attr->getDecimalMark()], ['', '.'], $amount);

        return number_format((float) $temp_balance, $new_attr->getPrecision(), $new_attr->getDecimalMark(), $new_attr->getThousandsSeparator());
    }

    public static function convertBalance(int $balance, string $oldCurrency, string $newCurrency): int
    {
        return money($balance, $oldCurrency)->swapAmountFor($newCurrency);
    }

    public static function prepareForMutator(int $balance, string $currency): string
    {
        return money($balance, $currency)->formatSimple();
    }

    public static function prepareForAccessor(string $balance, string $currency): int
    {
        return money($balance, $currency, true)->getAmount();
    }

    public static function handleCurrencyChange(Set $set, $state): void
    {
        $currency = currency($state);
        $defaultCurrencyCode = CurrencyAccessor::getDefaultCurrency();
        $forexEnabled = Forex::isEnabled();
        $exchangeRate = $forexEnabled ? Forex::getCachedExchangeRate($defaultCurrencyCode, $state) : null;

        $set('name', $currency->getName() ?? '');

        if ($forexEnabled && $exchangeRate !== null) {
            $set('rate', $exchangeRate);
        }
    }
}