currencyconvertermainwindow.cpp

#include "currencyconvertermainwindow.h"
#include "qjsonobject.h"
#include "ui_currencyconvertermainwindow.h"
#include <QNetworkRequest>
#include <QNetworkReply>
#include <QJsonDocument>
#include <QMessageBox>

CurrencyConverterMainWindow::CurrencyConverterMainWindow(QWidget *parent) :
    QMainWindow(parent),
    ui(new Ui::CurrencyConverterMainWindow)
{
    ui->setupUi(this);
    manager = new QNetworkAccessManager(this);
    connect(manager, &QNetworkAccessManager::finished, this, &CurrencyConverterMainWindow::onManagerFinished);

    // Connect button click signal to currency conversion function
    connect(ui->currencyButton, &QPushButton::clicked, this, &CurrencyConverterMainWindow::convertCurrency);

    // Set the background color of the main window
    setStyleSheet("QMainWindow { background-color: #2c3e50; }");

    // Set the background color and text color of QTextEdit widgets
    ui->uservalue->setStyleSheet("QTextEdit {"
                                 "background-color: #34495e;"
                                 "border: 1px solid #ccc;"
                                 "border-radius: 5px;"
                                 "padding: 5px;"
                                 "color: #f0f0f0;"
                                 "}");
    ui->useroutput->setStyleSheet("QTextEdit {"
                                  "background-color: #34495e;"
                                  "border: 1px solid #ccc;"
                                  "border-radius: 5px;"
                                  "padding: 5px;"
                                  "color: #f0f0f0;"
                                  "}");

    // Set the background color and text color of QPushButton
    ui->currencyButton->setStyleSheet("QPushButton { background-color: #3498db; color: white; padding: 5px; border-radius: 5px; }"
                                      "QPushButton:hover { background-color: #2980b9; }"
                                      "QPushButton:pressed { background-color: #1a5276; }");

    // Initialize and populate the currency combo box
    QStringList currencyList = {"USD", "INR", "EUR", "GBP", "JPY","CNY","PKR"};  // Add more currencies as needed
    QStringList desiredCurrency = {"MYR"};
    ui->currencyComboBox->addItems(currencyList);
    ui->currencyComboBox_2->addItems(desiredCurrency);
    ui->uservalue->installEventFilter(this);

    connect(ui->back2,&QPushButton::clicked,[=](){
        emit this->back2();
    });
    // Connect the combo box selection change signal to the appropriate slot
    connect(ui->currencyComboBox, QOverload<int>::of(&QComboBox::currentIndexChanged), this, &CurrencyConverterMainWindow::onCurrencySelectionChanged);
}

void CurrencyConverterMainWindow::onManagerFinished(QNetworkReply* reply)
{
    if (reply->error()) {
        qDebug() << reply->errorString();
        QMessageBox::critical(this, "Error", "There was an issue with the currency conversion API: " + reply->errorString());
        return;
    }

    QString answer = reply->readAll();
    qDebug() << "API Response: " << answer;  // Print the entire API response

    QJsonDocument jsonResponse = QJsonDocument::fromJson(answer.toUtf8());

    if (!jsonResponse.isObject()) {
        qDebug() << "Invalid JSON response";
        QMessageBox::critical(this, "Error", "Invalid JSON response from the currency conversion API.");
        return;
    }

    QJsonObject jsonObject = jsonResponse.object();

    if (!jsonObject.contains("conversion_rates") || !jsonObject["conversion_rates"].isObject()) {
        qDebug() << "Conversion rates not found in JSON response";
        QMessageBox::critical(this, "Error", "Conversion rates not found in the JSON response from the currency conversion API.");
        return;
    }

    QJsonObject conversionRatesObject = jsonObject["conversion_rates"].toObject();

    if (!conversionRatesObject.contains("MYR")) {  // Check if the target currency exists in the conversion rates
        qDebug() << "Target currency not found in conversion rates";
        QMessageBox::critical(this, "Error", "Target currency not found in conversion rates.");
        return;
    }

    conversionRate = conversionRatesObject["MYR"].toDouble();
}

bool CurrencyConverterMainWindow::eventFilter(QObject *obj, QEvent *event) {
    if (obj == ui->uservalue && event->type() == QEvent::MouseButtonPress) {
        // Handle the mouse press event
        ui->uservalue->clear();
        return true; // Event handled
    }

    // Call the base class implementation for other events
    return QMainWindow::eventFilter(obj, event);
}

void CurrencyConverterMainWindow::cleartext() {
    ui->uservalue->clear();
}

void CurrencyConverterMainWindow::convertCurrency()
{
    // Perform currency conversion

    double input = ui->uservalue->toPlainText().toDouble();
    double output = input * conversionRate;

    qDebug() << "Input: " << input;
    qDebug() << "Conversion Rate: " << conversionRate;
    qDebug() << "Output: " << output;

    // Ensure conversion rate is valid (not zero)
    if (input != 0.0 && !std::isnan(input)) {

        ui->useroutput->setText(QString::number(output,'f', 2));

        QMessageBox::information(this, "Success", "The currency conversion has taken place successfully.");

    } else if (input == 0.0){

        QMessageBox::critical(this, "Error", "Please enter a valid value.");

    } else if (input < 0){

        QMessageBox::critical(this, "Error", "Dont play play:)");

    } else {

        QMessageBox::critical(this, "Error", "Please enter a valid numeric value.");

    }
}

// Handle currency selection change
void CurrencyConverterMainWindow::onCurrencySelectionChanged()
{
    // Fetch the conversion rate when the currency selection changes
    manager->get(QNetworkRequest(QUrl("https://v6.exchangerate-api.com/v6/9ef329ffdad401628eca2190/latest/" + ui->currencyComboBox->currentText())));
}

CurrencyConverterMainWindow::~CurrencyConverterMainWindow()
{
    delete ui;
}