//server .pro

#-------------------------------------------------
#
# Project created by QtCreator 2017-02-06T16:50:39
#
#-------------------------------------------------

QT       += core gui network

greaterThan(QT_MAJOR_VERSION, 4): QT += widgets

TARGET = server
TEMPLATE = app

# The following define makes your compiler emit warnings if you use
# any feature of Qt which as been marked as deprecated (the exact warnings
# depend on your compiler). Please consult the documentation of the
# deprecated API in order to know how to port your code away from it.
DEFINES += QT_DEPRECATED_WARNINGS

# You can also make your code fail to compile if you use deprecated APIs.
# In order to do so, uncomment the following line.
# You can also select to disable deprecated APIs only up to a certain version of Qt.
#DEFINES += QT_DISABLE_DEPRECATED_BEFORE=0x060000    # disables all the APIs deprecated before Qt 6.0.0


SOURCES += main.cpp\
        mainwindow.cpp

HEADERS  += mainwindow.h

FORMS    += mainwindow.ui


//server .h

#ifndef MAINWINDOW_H
#define MAINWINDOW_H

#include <QTcpServer>
#include <QTcpSocket>
#include <QDebug>
#include <QMessageBox>
#include <QMainWindow>

namespace Ui {
class MainWindow;
}

class MainWindow : public QMainWindow
{
    Q_OBJECT

public:
    explicit MainWindow(QWidget *parent = 0);
    ~MainWindow();

private slots:
    void on_pushButton_clicked();
    void newConn();
    void readSocket();

    void on_btnSend_clicked();

private:
    Ui::MainWindow *ui;

    bool serverStarted = false;
    QTcpServer *tcpServer;
    QTcpSocket *clientSocket = nullptr;
    QDataStream in;
};

#endif // MAINWINDOW_H


//server .cpp

#include "mainwindow.h"
#include "ui_mainwindow.h"

MainWindow::MainWindow(QWidget *parent) :
    QMainWindow(parent),
    ui(new Ui::MainWindow)
{
    ui->setupUi(this);
    tcpServer = new QTcpServer(this);

}

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

void MainWindow::on_pushButton_clicked()
{
    if (!serverStarted) {

        if (!tcpServer->listen(QHostAddress::AnyIPv4, 5000)) {
            ui->lblServerStatus->setText("Failed to start server");
        }
        serverStarted = true;
        ui->pushButton->setText("Stop Server");
        ui->lblServerStatus->setText("Server Running");
        connect(tcpServer, SIGNAL(newConnection()),
                this, SLOT(newConn()));
    }
    else{
        clientSocket->disconnectFromHost();
        tcpServer->close();
        serverStarted = false;
        ui->pushButton->setText("Start Server");
        ui->lblServerStatus->setText("Server not running");
    }
}

void MainWindow::newConn(){
    ui->lblServerStatus->setText("New Connection Recieved");
    clientSocket = tcpServer->nextPendingConnection();

    connect(clientSocket, SIGNAL(readyRead()),
            this, SLOT(readSocket()));

    qDebug() << "ip = " << clientSocket->peerAddress().toString();
    qDebug() << "name = " << clientSocket->peerName();
    qDebug() << "port = " << QString::number(clientSocket->peerPort());

}


void MainWindow::on_btnSend_clicked()
{
    if (clientSocket != nullptr) {
        if (!clientSocket->isValid()) {
            qDebug() << "tcp socket invalid";
            return;
        }
        if (!clientSocket->isOpen()) {
            qDebug() << "tcp socket not open";
            return;
        }

        QByteArray block;
        QDataStream out(&block, QIODevice::WriteOnly);
        out.setVersion(QDataStream::Qt_4_0);

        out << ui->lineEdit->text();

//        QTcpSocket *clientConnection = tcpServer->nextPendingConnection();
//        connect(clientSocket, &QAbstractSocket::disconnected,
//                clientConnection, &QObject::deleteLater);

        if (!clientSocket->write(block)){
            QMessageBox::information(this, tr("Server"),tr("Could not send message"));
        }
//        clientConnection->disconnectFromHost();

    }
}

void MainWindow::readSocket(){
    in.setDevice(clientSocket);
    in.setVersion(QDataStream::Qt_4_0);

    in.startTransaction();

    QString nextFortune;
    in >> nextFortune;

    if (in.commitTransaction())
        ui->lblOut->setText(nextFortune);
}


//server .ui

<?xml version="1.0" encoding="UTF-8"?>
<ui version="4.0">
 <class>MainWindow</class>
 <widget class="QMainWindow" name="MainWindow">
  <property name="geometry">
   <rect>
    <x>0</x>
    <y>0</y>
    <width>499</width>
    <height>217</height>
   </rect>
  </property>
  <property name="windowTitle">
   <string>MainWindow</string>
  </property>
  <widget class="QWidget" name="centralWidget">
   <widget class="QPushButton" name="pushButton">
    <property name="geometry">
     <rect>
      <x>20</x>
      <y>20</y>
      <width>80</width>
      <height>22</height>
     </rect>
    </property>
    <property name="text">
     <string>Start Server</string>
    </property>
   </widget>
   <widget class="QPushButton" name="btnSend">
    <property name="geometry">
     <rect>
      <x>310</x>
      <y>100</y>
      <width>80</width>
      <height>22</height>
     </rect>
    </property>
    <property name="text">
     <string>Send Text</string>
    </property>
   </widget>
   <widget class="QLabel" name="lblOut">
    <property name="geometry">
     <rect>
      <x>20</x>
      <y>60</y>
      <width>331</width>
      <height>16</height>
     </rect>
    </property>
    <property name="text">
     <string>Recieved Text</string>
    </property>
   </widget>
   <widget class="QLineEdit" name="lineEdit">
    <property name="geometry">
     <rect>
      <x>10</x>
      <y>100</y>
      <width>291</width>
      <height>22</height>
     </rect>
    </property>
   </widget>
   <widget class="QLabel" name="lblServerStatus">
    <property name="geometry">
     <rect>
      <x>120</x>
      <y>20</y>
      <width>231</width>
      <height>16</height>
     </rect>
    </property>
    <property name="text">
     <string>Server Status</string>
    </property>
   </widget>
  </widget>
  <widget class="QMenuBar" name="menuBar">
   <property name="geometry">
    <rect>
     <x>0</x>
     <y>0</y>
     <width>499</width>
     <height>19</height>
    </rect>
   </property>
   <widget class="QMenu" name="menuServer">
    <property name="title">
     <string>Server</string>
    </property>
   </widget>
   <addaction name="menuServer"/>
  </widget>
  <widget class="QToolBar" name="mainToolBar">
   <attribute name="toolBarArea">
    <enum>TopToolBarArea</enum>
   </attribute>
   <attribute name="toolBarBreak">
    <bool>false</bool>
   </attribute>
  </widget>
  <widget class="QStatusBar" name="statusBar"/>
 </widget>
 <layoutdefault spacing="6" margin="11"/>
 <resources/>
 <connections/>
</ui>