3
0
mirror of https://github.com/Qortal/Brooklyn.git synced 2025-02-14 11:15:54 +00:00
Brooklyn/plasma/workspace/runners/calculator/qalculate_engine.cpp
2022-04-02 18:24:21 +05:00

125 lines
3.7 KiB
C++

/*
SPDX-FileCopyrightText: 2010 Matteo Agostinelli <agostinelli@gmail.com>
SPDX-License-Identifier: LGPL-2.0-or-later
*/
#include "qalculate_engine.h"
#include <libqalculate/Calculator.h>
#include <libqalculate/ExpressionItem.h>
#include <libqalculate/Function.h>
#include <libqalculate/Prefix.h>
#include <libqalculate/Unit.h>
#include <libqalculate/Variable.h>
#include <QApplication>
#include <QClipboard>
#include <QDebug>
#include <QFile>
#include <KIO/Job>
#include <KLocalizedString>
#include <KProtocolManager>
QAtomicInt QalculateEngine::s_counter;
QalculateEngine::QalculateEngine(QObject *parent)
: QObject(parent)
{
s_counter.ref();
if (!CALCULATOR) {
new Calculator();
CALCULATOR->terminateThreads();
CALCULATOR->loadGlobalDefinitions();
CALCULATOR->loadLocalDefinitions();
CALCULATOR->loadGlobalCurrencies();
CALCULATOR->loadExchangeRates();
}
}
QalculateEngine::~QalculateEngine()
{
if (s_counter.deref()) {
delete CALCULATOR;
CALCULATOR = nullptr;
}
}
void QalculateEngine::updateExchangeRates()
{
QUrl source = QUrl("http://www.ecb.int/stats/eurofxref/eurofxref-daily.xml");
QUrl dest = QUrl::fromLocalFile(QFile::decodeName(CALCULATOR->getExchangeRatesFileName().c_str()));
KIO::Job *getJob = KIO::file_copy(source, dest, -1, KIO::Overwrite | KIO::HideProgressInfo);
connect(getJob, &KJob::result, this, &QalculateEngine::updateResult);
}
void QalculateEngine::updateResult(KJob *job)
{
if (job->error()) {
qDebug() << "The exchange rates could not be updated. The following error has been reported:" << job->errorString();
} else {
// the exchange rates have been successfully updated, now load them
CALCULATOR->loadExchangeRates();
}
}
QString QalculateEngine::evaluate(const QString &expression, bool *isApproximate)
{
if (expression.isEmpty()) {
return QString();
}
QString input = expression;
// Make sure to use toLocal8Bit, the expression can contain non-latin1 characters
QByteArray ba = input.replace(QChar(0xA3), "GBP").replace(QChar(0xA5), "JPY").replace('$', "USD").replace(QChar(0x20AC), "EUR").toLocal8Bit();
const char *ctext = ba.data();
CALCULATOR->terminateThreads();
EvaluationOptions eo;
eo.auto_post_conversion = POST_CONVERSION_BEST;
eo.keep_zero_units = false;
eo.parse_options.angle_unit = ANGLE_UNIT_RADIANS;
eo.structuring = STRUCTURING_SIMPLIFY;
// suggested in https://github.com/Qalculate/libqalculate/issues/16
// to avoid memory overflow for seemingly innocent calculations (Bug 277011)
eo.approximation = APPROXIMATION_APPROXIMATE;
CALCULATOR->setPrecision(16);
MathStructure result = CALCULATOR->calculate(ctext, eo);
PrintOptions po;
po.number_fraction_format = FRACTION_DECIMAL;
po.indicate_infinite_series = false;
po.use_all_prefixes = false;
po.use_denominator_prefix = true;
po.negative_exponents = false;
po.lower_case_e = true;
po.base_display = BASE_DISPLAY_NORMAL;
#if defined(QALCULATE_MAJOR_VERSION) && defined(QALCULATE_MINOR_VERSION) \
&& (QALCULATE_MAJOR_VERSION > 2 || (QALCULATE_MAJOR_VERSION == 2 && QALCULATE_MINOR_VERSION >= 2))
po.interval_display = INTERVAL_DISPLAY_SIGNIFICANT_DIGITS;
#endif
result.format(po);
m_lastResult = result.print(po).c_str();
if (isApproximate) {
*isApproximate = result.isApproximate();
}
return m_lastResult;
}
void QalculateEngine::copyToClipboard(bool flag)
{
Q_UNUSED(flag);
QApplication::clipboard()->setText(m_lastResult);
}