/***************************************************************************
* Copyright (c) 2013 Abdurrahman AVCI <abdurrahmanavci@gmail.com>
*
* This program 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 2 of the License, or
* (at your option) any later version.
*
* This program 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 this program; if not, write to the
* Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
***************************************************************************/

#include "SeatManager.h"

#include "DaemonApp.h"
#include "Seat.h"

#include <QDBusConnection>
#include <QDBusMessage>
#include <QDBusPendingReply>
#include <QDBusContext>

#include <Login1Manager.h>
#include <Login1Session.h>
#include "LogindDBusTypes.h"

namespace SDDM {

    class LogindSeat : public QObject {
    Q_OBJECT
    public:
        LogindSeat(const QString &name, const QDBusObjectPath &objectPath);
        QString name() const;
        bool canGraphical() const;
    Q_SIGNALS:
        void canGraphicalChanged(bool);
    private Q_SLOTS:
        void propertiesChanged(const QString &interface, const QVariantMap &changedProperties , const QStringList &invalidatedProperties);
    private:
        QString m_name;
        bool m_canGraphical;
    };

    LogindSeat::LogindSeat(const QString& name, const QDBusObjectPath& objectPath):
        m_name(name),
        m_canGraphical(false)
    {
        QDBusConnection::systemBus().connect(Logind::serviceName(), objectPath.path(), QStringLiteral("org.freedesktop.DBus.Properties"), QStringLiteral("PropertiesChanged"), this, SLOT(propertiesChanged(QString,QVariantMap,QStringList)));

        auto canGraphicalMsg = QDBusMessage::createMethodCall(Logind::serviceName(), objectPath.path(), QStringLiteral("org.freedesktop.DBus.Properties"), QStringLiteral("Get"));
        canGraphicalMsg << Logind::seatIfaceName() << QStringLiteral("CanGraphical");

        QDBusPendingReply<QVariant> reply = QDBusConnection::systemBus().asyncCall(canGraphicalMsg);
        QDBusPendingCallWatcher *watcher = new QDBusPendingCallWatcher(reply);
        connect(watcher, &QDBusPendingCallWatcher::finished, this, [=]() {
            watcher->deleteLater();
            if (!reply.isValid())
                return;

            bool value = reply.value().toBool();
            if (value != m_canGraphical) {
                m_canGraphical = value;
                emit canGraphicalChanged(m_canGraphical);
            }
        });
    }

    bool LogindSeat::canGraphical() const
    {
        return m_canGraphical;
    }

    QString LogindSeat::name() const
    {
        return m_name;
    }

    void LogindSeat::propertiesChanged(const QString& interface, const QVariantMap& changedProperties, const QStringList& invalidatedProperties)
    {
        Q_UNUSED(invalidatedProperties);
        if (interface != Logind::seatIfaceName()) {
            return;
        }

        if (changedProperties.contains(QStringLiteral("CanGraphical"))) {
            m_canGraphical = changedProperties[QStringLiteral("CanGraphical")].toBool();
            emit canGraphicalChanged(m_canGraphical);
        }
    }

    void SeatManager::initialize() {
        if (DaemonApp::instance()->testing() || !Logind::isAvailable()) {
            //if we don't have logind/CK2, just create a single seat immediately and don't do any other connections
            createSeat(QStringLiteral("seat0"));
            return;
        }

        //fetch seats
        auto listSeatsMsg = QDBusMessage::createMethodCall(Logind::serviceName(), Logind::managerPath(), Logind::managerIfaceName(), QStringLiteral("ListSeats"));
        QDBusPendingReply<NamedSeatPathList> reply = QDBusConnection::systemBus().asyncCall(listSeatsMsg);

        QDBusPendingCallWatcher *watcher = new QDBusPendingCallWatcher(reply);
        connect(watcher, &QDBusPendingCallWatcher::finished, this, [=]() {
            watcher->deleteLater();
            const auto seats = reply.value();
            for(const NamedSeatPath &seat : seats) {
                logindSeatAdded(seat.name, seat.path);
            }
        });

        QDBusConnection::systemBus().connect(Logind::serviceName(), Logind::managerPath(), Logind::managerIfaceName(), QStringLiteral("SecureAttentionKey"), this, SLOT(logindSecureAttentionKey(QString,QDBusObjectPath)));
        QDBusConnection::systemBus().connect(Logind::serviceName(), Logind::managerPath(), Logind::managerIfaceName(), QStringLiteral("SeatNew"), this, SLOT(logindSeatAdded(QString,QDBusObjectPath)));
        QDBusConnection::systemBus().connect(Logind::serviceName(), Logind::managerPath(), Logind::managerIfaceName(), QStringLiteral("SeatRemoved"), this, SLOT(logindSeatRemoved(QString,QDBusObjectPath)));
    }

    void SeatManager::createSeat(const QString &name) {
        // create a seat
        Seat *seat = new Seat(name, this);

        // add to the list
        m_seats.insert(name, seat);

        // emit signal
        emit seatCreated(name);
    }

    void SeatManager::removeSeat(const QString &name) {
        // check if seat exists
        if (!m_seats.contains(name))
            return;

        // remove from the list
        Seat *seat = m_seats.take(name);

        // delete seat
        seat->deleteLater();

        // emit signal
        emit seatRemoved(name);
    }

    void SeatManager::switchToGreeter(const QString &name) {
        // check if seat exists
        if (!m_seats.contains(name))
            return;

        // Switch to existing greeter session if available
        if (Logind::isAvailable()) {
            OrgFreedesktopLogin1ManagerInterface manager(Logind::serviceName(), Logind::managerPath(), QDBusConnection::systemBus());
            auto reply = manager.ListSessions();
            reply.waitForFinished();

            const auto info = reply.value();
            for(const SessionInfo &s : reply.value()) {
                if (s.userName == QLatin1String("sddm")) {
                    OrgFreedesktopLogin1SessionInterface session(Logind::serviceName(), s.sessionPath.path(), QDBusConnection::systemBus());
                    if (session.service() == QLatin1String("sddm-greeter") && session.seat().name == name) {
                        session.Activate();
                        return;
                    }
                }
            }
        }

        // switch to greeter
        m_seats.value(name)->createDisplay(Display::defaultDisplayServerType());
    }

    void SDDM::SeatManager::logindSecureAttentionKey(const QString& name, const QDBusObjectPath& objectPath)
    {
        Q_UNUSED(objectPath);
        daemonApp->seatManager()->switchToGreeter(name);
    }

    void SDDM::SeatManager::logindSeatAdded(const QString& name, const QDBusObjectPath& objectPath)
    {
        auto logindSeat = new LogindSeat(name, objectPath);
        connect(logindSeat, &LogindSeat::canGraphicalChanged, this, [=]() {
            if (logindSeat->canGraphical()) {
                createSeat(logindSeat->name());
            } else {
                removeSeat(logindSeat->name());
            }
        });

        m_systemSeats.insert(name, logindSeat);
    }

    void SDDM::SeatManager::logindSeatRemoved(const QString& name, const QDBusObjectPath& objectPath)
    {
        Q_UNUSED(objectPath);
        auto logindSeat = m_systemSeats.take(name);
        delete logindSeat;
        removeSeat(name);
    }
}

#include "SeatManager.moc"