firefly-iii/app/Support/Twig/Extension/TransactionJournal.php

<?php
/**
 * TransactionJournal.php
 * Copyright (c) 2017 thegrumpydictator@gmail.com
 *
 * This file is part of Firefly III.
 *
 * Firefly III is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * Firefly III is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with Firefly III.  If not, see <http://www.gnu.org/licenses/>.
 */

declare(strict_types=1);

namespace FireflyIII\Support\Twig\Extension;

use FireflyIII\Models\Transaction;
use FireflyIII\Models\TransactionJournal as JournalModel;
use FireflyIII\Models\TransactionType;
use FireflyIII\Support\SingleCacheProperties;
use Twig_Extension;

class TransactionJournal extends Twig_Extension
{

    /**
     * @param JournalModel $journal
     *
     * @return string
     */
    function totalAmount(JournalModel $journal): string
    {
        $cache = new SingleCacheProperties;
        $cache->addProperty('total-amount');
        $cache->addProperty($journal->id);
        $cache->addProperty($journal->updated_at);
        if ($cache->has()) {
            return $cache->get();
        }

        $transactions = $journal->transactions()->where('amount', '>', 0)->get();
        $totals       = [];
        $type         = $journal->transactionType->type;
        /** @var Transaction $transaction */
        foreach ($transactions as $transaction) {
            $currencyId = $transaction->transaction_currency_id;
            $currency   = $transaction->transactionCurrency;

            if (!isset($totals[$currencyId])) {
                $totals[$currencyId] = [
                    'amount'   => '0',
                    'currency' => $currency,
                ];
            }
            $totals[$currencyId]['amount'] = bcadd($transaction->amount, $totals[$currencyId]['amount']);

            if (!is_null($transaction->foreign_currency_id)) {
                $foreignId = $transaction->foreign_currency_id;
                $foreign   = $transaction->foreignCurrency;
                if (!isset($totals[$foreignId])) {
                    $totals[$foreignId] = [
                        'amount'   => '0',
                        'currency' => $foreign,
                    ];
                }
                $totals[$foreignId]['amount'] = bcadd($transaction->foreign_amount, $totals[$foreignId]['amount']);
            }
        }
        $array = [];
        foreach ($totals as $total) {
            if ($type === TransactionType::WITHDRAWAL) {
                $total['amount'] = bcmul($total['amount'], '-1');
            }
            $array[] = app('amount')->formatAnything($total['currency'], $total['amount']);
        }
        $txt = join(' / ', $array);
        $cache->store($txt);

        return $txt;

    }

}