Labcontrol/src/Lib/clienthelpnotificationserver.cpp

/*
 * Copyright 2014-2016 Markus Prasser
 *
 * This file is part of Labcontrol.
 *
 *  Labcontrol is free software: you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation, either version 3 of the License, or
 *  (at your option) any later version.
 *
 *  Labcontrol is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with Labcontrol.  If not, see <http://www.gnu.org/licenses/>.
 */

#include "clienthelpnotificationserver.h"

lc::ClientHelpNotificationServer::ClientHelpNotificationServer( const QMap< QString, Client* > * const argClientIPsToClientsMap,
                                const QString &argServerIP, const unsigned short int &argServerPort, QObject *argParent ) :
    QObject{ argParent },
    clientIPsToClientsMap{ argClientIPsToClientsMap },
    hostAddress{ argServerIP },
    serverPort{ argServerPort }
{
    QNetworkConfigurationManager manager;
    if ( manager.capabilities() & QNetworkConfigurationManager::NetworkSessionRequired ) {
        // Get saved network configuration
        QSettings settings{ QSettings::UserScope, QLatin1String{ "QtProject" } };
        settings.beginGroup( QLatin1String{ "QtNetwork" } );
        const QString id = settings.value( QLatin1String{ "DefaultNetworkConfiguration" } ).toString();
        settings.endGroup();

        // If the saved network configuration is not currently discovered use the system default
        QNetworkConfiguration config = manager.configurationFromIdentifier( id );
        if ( ( config.state() & QNetworkConfiguration::Discovered ) != QNetworkConfiguration::Discovered ) {
            config = manager.defaultConfiguration();
        }
        networkSession = new QNetworkSession{ config, this };
        connect( networkSession, &QNetworkSession::opened,
                 this, &ClientHelpNotificationServer::OpenSession );
        networkSession->open();
    } else {
        OpenSession();
    }

    connect( helpMessageServer, &QTcpServer::newConnection,
             this, &ClientHelpNotificationServer::SendReply );
}

void lc::ClientHelpNotificationServer::OpenSession() {
    // Save the used configuration
    if ( networkSession ) {
        QNetworkConfiguration config = networkSession->configuration();
        QString id;
        if ( config.type() == QNetworkConfiguration::UserChoice ) {
            id = networkSession->sessionProperty( QLatin1String{ "UserChoiceConfiguration" } ).toString();
        } else {
            id = config.identifier();
        }

        QSettings settings( QSettings::UserScope, QLatin1String{ "QtProject" } );
        settings.beginGroup( QLatin1String{ "QtNetwork" } );
        settings.setValue( QLatin1String{ "DefaultNetworkConfiguration" }, id );
        settings.endGroup();
    }

    helpMessageServer = new QTcpServer{ this };
    if ( !helpMessageServer->listen( hostAddress, serverPort ) ) {
        QMessageBox messageBox{ QMessageBox::Critical, tr( "Unable to start the client help notification server" ),
                    tr( "Unable to start the client help notification server.\nThe following error occurred:\n\n%1." ).arg( helpMessageServer->errorString() ), QMessageBox::Ok };
        messageBox.exec();
        return;
    }
}

void lc::ClientHelpNotificationServer::SendReply() {
    QByteArray block;
    QDataStream out{ &block, QIODevice::WriteOnly };
    out.setVersion( QDataStream::Qt_5_2 );
    out << ( quint16 )0;
    out << QString{ "Help demand retrieved." };
    out.device()->seek( 0 );
    out << ( quint16 )( block.size() - sizeof( quint16 ) );

    QTcpSocket *clientConnection = helpMessageServer->nextPendingConnection();
    QString peerAddress = clientConnection->peerAddress().toString();
    QString peerName;
    bool unknownClient = false;
    if ( clientIPsToClientsMap->contains( peerAddress ) ) {
        peerName = ( *clientIPsToClientsMap )[ peerAddress ]->name;
    } else {
        unknownClient = true;
    }

    connect( clientConnection, &QTcpSocket::disconnected, clientConnection, &QTcpSocket::deleteLater );
    clientConnection->write( block );
    clientConnection->disconnectFromHost();

    if ( unknownClient ) {
        QMessageBox requestReceivedBox{ QMessageBox::Information, tr( "Unknown client asked for help."),
                    tr( "An unknown client with IP '%1' asked for help.").arg( peerAddress ), QMessageBox::Ok };
        requestReceivedBox.exec();
    } else {
        QMessageBox requestReceivedBox{ QMessageBox::Information, tr( "'%1' asked for help.").arg( peerName ),
                    tr( "'%1' asked for help.").arg( peerName ), QMessageBox::Ok };
        requestReceivedBox.exec();
    }
}