app/sources/baseconn.cpp

#include "headers/baseconn.h"

BaseConn::BaseConn(QObject *parent) : QObject(parent)
{
    socket = new QTcpSocket();
    this->setState("disconnected");
}

bool BaseConn::connectToHost() {

    setState("connecting");
    this->connection_progress = 0;
    QEventLoop loop;
    QTimer timer;

    timer.setSingleShot(true);
    // quit the loop when the timer times out
    loop.connect(&timer, SIGNAL(timeout()), &loop, SLOT(quit()));
    //quit the loop when the connection was established
    loop.connect(this->socket, SIGNAL(connected()), &loop, SLOT(quit()));
    // start the timer before starting to connect
    timer.start(3000);
    //connect
    this->socket->connectToHost(this->ip, this->port);

    //wait for the connection to finish (programm gets stuck in here)
    loop.exec();

    //loop finished

    if(timer.remainingTime() == -1){
        //the time has been triggered -> timeout
        this->socket->abort();
        setState("disconnected");
        return(false);
    }

    // stop the timer as the connection has been established
    timer.stop();
    connect(this->socket, &QTcpSocket::readyRead, this, &BaseConn::readyRead);
    this->connection_progress = 100;
    setState("connected");
    return(true);
}

QString BaseConn::sendCommand(QString command){
        QByteArray arrBlock;
        QDataStream out(&arrBlock, QIODevice::WriteOnly);
        //out.setVersion(QDataStream::Qt_5_10);
        out << quint16(0) << command;

        out.device()->seek(0);
        out << quint16(arrBlock.size() - sizeof(quint16));

        QEventLoop loop;
        QTimer timer;

        timer.setSingleShot(true);
        // quit the loop when the timer times out
        loop.connect(&timer, SIGNAL(timeout()), &loop, SLOT(quit()));
        //quit the loop when the connection was established
        loop.connect(this, &BaseConn::gotReply, &loop, &QEventLoop::quit);
        // start the timer before starting to connect
        timer.start(3000);

        //write data

        socket->write(arrBlock);

        //wait for an answer to finish (programm gets stuck in here)
        loop.exec();

        //loop finished
        if(timer.remainingTime() == -1){
            //the time has been triggered -> timeout
            return("timeout");
        }

        // stop the timer as the connection has been established
        timer.stop();


        return(this->latestReadReply);
}

void BaseConn::readyRead() {
    qDebug() << "readyRead";
    QDataStream in(socket);
    //in.setVersion(QDataStream::Qt_5_10);
    qint16 nextBlockSize = 0;
    for (;;)
    {
        if (!nextBlockSize)
        {
            if (socket->bytesAvailable() < sizeof(quint16)) { break; }
            in >> nextBlockSize;
        }

        if (socket->bytesAvailable() < nextBlockSize) { break; }

        QString str; in >> str;

//        if (str == "0")
//        {
//            str = "Connection closed";
//            closeConnection();
//        }
        nextBlockSize = 0;
        latestReadReply = str;
        emit gotReply();

    }
}

void BaseConn::setIP(const QString &ipAdress){
    this->ip = ipAdress;
}

QString BaseConn::getIP() const
{
    return(this->ip);
}

QString BaseConn::getState() const
{
    return(this->state);
}

void BaseConn::setState(QString newState){
    this->state = newState;
    emit stateChanged();
}

int BaseConn::getProgress() const
{
    return(connection_progress);
}