#include <QCoreApplication>
#include <QDebug>
#include <QString>
#include <QPointer>
#include <QObject>
#include <QSharedPointer>

QString returnString(QString string) {
    QString returnString = string;
    returnString.append("bar");
    return returnString;
}

void testQPointer() {
    // QObject*
    QPointer<QObject> object;
    qDebug() << "testQPointer created the QPointer - QPointer is null: " << object.isNull() << object;
    object = new QObject;
    qDebug() << "testQPointer initialized the QObject - QPointer is null: " << object.isNull() << object;
    delete object;
    qDebug() << "testQPointer deleted QObject - QPointer is null: " << object.isNull() << object;
}

void testQSharedPointer(QObject& object) {
    QSharedPointer<QObject> object2(&object);
}

void testImplicitSharing() {
    QString foo = "foo";
    QString bar = foo;
    bar.append("bar");
}

void testSignalsAndSlots() {
    QPointer<QObject> sender = new QObject;
    QPointer<QObject> receiver = new QObject;

    QObject::connect(sender, SIGNAL(destroyed()),
                     receiver, SLOT(deleteLater()));
    qDebug() << "Deleting sender" << sender;
    sender->deleteLater();
    qDebug() << "sender" << sender;
    qDebug() << "receiver" << receiver;
}

int main(int argc, char *argv[]) {
    QCoreApplication a(argc, argv);
    QString p = "foo";
    qDebug() << "returnString" << p << returnString(p);
    testQPointer();
    QPointer<QObject> sp = new QObject;
    qDebug() << "testQSharedPointer" << sp;
    testQSharedPointer(*sp.data());
    qDebug() << "testQSharedPointer" << sp;
    qDebug() << "testImplicitSharing";
    testImplicitSharing();
    qDebug() << "testSignalsAndSlots";
    testSignalsAndSlots();
    return 0;
}