/*
 * Copyright 2018 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 "helpmessagewindow.h"
#include "ui_helpmessagewindow.h"

#include <QNetworkConfigurationManager>
#include <QNetworkSession>
#include <QSettings>
#include <QTcpSocket>

#include <iostream>

lcHelpMessageWindow::lcHelpMessageWindow(const QString &argServerIP,
                                         const quint16 argServerPort,
                                         QWidget *const argParent) :
    QMainWindow{argParent},
    serverAddress{argServerIP},
    serverPort{argServerPort},
    ui{new Ui::HelpMessageWindow}
{
    helpMessageSocket = new QTcpSocket{this};

    ui->setupUi(this);
    connect(ui->PBAskForHelp, &QPushButton::clicked,
            this, &lcHelpMessageWindow::RequestHelp);
    connect(helpMessageSocket, &QTcpSocket::readyRead,
            this, &lcHelpMessageWindow::ReadHelpReply);
    connect(helpMessageSocket,
            static_cast<void (QTcpSocket::*)(QAbstractSocket::SocketError)>
            (&QAbstractSocket::error),
            this, &lcHelpMessageWindow::DisplayError);

    QNetworkConfigurationManager manager;
    if (manager.capabilities()
            & QNetworkConfigurationManager::NetworkSessionRequired) {
        // Get saved network configuration
        QSettings settings{QSettings::UserScope, QLatin1String{"QtProject"}};
        settings.beginGroup(QLatin1String{"QtNetwork"});
        const auto id{settings.value("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, &lcHelpMessageWindow::OpenedSession);

        networkSession->open();
    }
}

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

void lcHelpMessageWindow::DisplayError(QAbstractSocket::SocketError argSocketError) {
    QString errorMessage;
    switch (argSocketError) {
    case QAbstractSocket::RemoteHostClosedError:
        return;
    case QAbstractSocket::HostNotFoundError:
        errorMessage = tr("An error occurred: The server could not be found for"
                          " error reporting:\n");
        break;
    case QAbstractSocket::ConnectionRefusedError:
        errorMessage = tr("An error occurred: The connection was refused by the"
                          " laboratory server:\n");
        break;
    default:
        errorMessage = tr("The following error occured:\n");
    }
    errorMessage.append(tr("%1").arg(helpMessageSocket->errorString()));
    errorMessage.append("\n\nPlease raise your hand to notify the experimenters.");
    ui->LSendingSuccess->setText(errorMessage);
}

void lcHelpMessageWindow::OpenedSession() {
    // Save the used configuration
    QString id;
    if (const auto config{networkSession->configuration()};
            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();
}

void lcHelpMessageWindow::ReadHelpReply() {
    QDataStream in{helpMessageSocket};
    in.setVersion(QDataStream::Qt_5_2);

    if (blockSize == 0) {
        if (helpMessageSocket->bytesAvailable()
                < static_cast<int>(sizeof(quint16))) {
            return;
        }

        in >> blockSize;
    }

    if (helpMessageSocket->bytesAvailable() < blockSize) {
        return;
    }

    QString serverAnswer;
    in >> serverAnswer;

    if (serverAnswer == "Help demand retrieved.") {
        ui->LSendingSuccess->setText(tr("Help message successfully"
                                        " sent.\nPlease wait for the"
                                        " experimenter to show up at your booth."));
        ui->PBAskForHelp->setEnabled(false);
    } else {
        ui->LSendingSuccess->setText(tr("An error occurred sending the help"
                                        " message. Please raise your"
                                        " arm.\n\n'%1'").arg(serverAnswer));
    }
}

void lcHelpMessageWindow::RequestHelp() {
    blockSize = 0;
    helpMessageSocket->abort();
    helpMessageSocket->connectToHost(serverAddress, serverPort);
}