/**
 * Copyright 2015 Holger Kaelberer <holger.k@elberer.de>
 *
 * 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) version 3 or any later version
 * accepted by the membership of KDE e.V. (or its successor approved
 * by the membership of KDE e.V.), which shall act as a proxy
 * defined in Section 14 of version 3 of the license.
 *
 * 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, see <http://www.gnu.org/licenses/>.
 */

#include <QtDBus/QDBusConnection>
#include <QtDBus/QDBusInterface>
#include <QtDBus/QDBusArgument>
#include <QtDebug>
#include <QLoggingCategory>
#include <QStandardPaths>
#include <QImage>
#include <KConfig>
#include <KConfigGroup>
#include <kiconloader.h>
#include <kicontheme.h>

#include <core/device.h>
#include <core/kdeconnectplugin.h>

#include "notificationslistener.h"
#include "sendnotificationsplugin.h"
#include "sendnotification_debug.h"
#include "notifyingapplication.h"

//In older Qt released, qAsConst isnt available
#include "qtcompat_p.h"

NotificationsListener::NotificationsListener(KdeConnectPlugin* aPlugin)
    : QDBusAbstractAdaptor(aPlugin),
      m_plugin(aPlugin)
{
    qRegisterMetaTypeStreamOperators<NotifyingApplication>("NotifyingApplication");

    bool ret = QDBusConnection::sessionBus()
                .registerObject(QStringLiteral("/org/freedesktop/Notifications"),
                                this,
                                QDBusConnection::ExportScriptableContents);
    if (!ret)
        qCWarning(KDECONNECT_PLUGIN_SENDNOTIFICATION)
                << "Error registering notifications listener for device"
                << m_plugin->device()->name() << ":"
                << QDBusConnection::sessionBus().lastError();
    else
        qCDebug(KDECONNECT_PLUGIN_SENDNOTIFICATION)
                << "Registered notifications listener for device"
                << m_plugin->device()->name();

    QDBusInterface iface(QStringLiteral("org.freedesktop.DBus"), QStringLiteral("/org/freedesktop/DBus"),
                         QStringLiteral("org.freedesktop.DBus"));
    iface.call(QStringLiteral("AddMatch"),
               "interface='org.freedesktop.Notifications',member='Notify',type='method_call',eavesdrop='true'");

    setTranslatedAppName();
    loadApplications();

    connect(m_plugin->config(), &KdeConnectPluginConfig::configChanged, this, &NotificationsListener::loadApplications);
}

NotificationsListener::~NotificationsListener()
{
    qCDebug(KDECONNECT_PLUGIN_SENDNOTIFICATION) << "Destroying NotificationsListener";
    QDBusInterface iface(QStringLiteral("org.freedesktop.DBus"), QStringLiteral("/org/freedesktop/DBus"),
                         QStringLiteral("org.freedesktop.DBus"));
    QDBusMessage res = iface.call(QStringLiteral("RemoveMatch"),
                                  "interface='org.freedesktop.Notifications',member='Notify',type='method_call',eavesdrop='true'");
    QDBusConnection::sessionBus().unregisterObject(QStringLiteral("/org/freedesktop/Notifications"));
}

void NotificationsListener::setTranslatedAppName()
{
    QString filePath = QStandardPaths::locate(QStandardPaths::GenericDataLocation, QStringLiteral("knotifications5/kdeconnect.notifyrc"), QStandardPaths::LocateFile);
    if (filePath.isEmpty()) {
        qCDebug(KDECONNECT_PLUGIN_SENDNOTIFICATION) << "Couldn't find kdeconnect.notifyrc to hide kdeconnect notifications on the devices. Using default name.";
        m_translatedAppName = QStringLiteral("KDE Connect");
        return;
    }

    KConfig config(filePath, KConfig::OpenFlag::SimpleConfig);
    KConfigGroup globalgroup(&config, QStringLiteral("Global"));
    m_translatedAppName = globalgroup.readEntry(QStringLiteral("Name"), QStringLiteral("KDE Connect"));
}

void NotificationsListener::loadApplications()
{
    m_applications.clear();
    const QVariantList list = m_plugin->config()->getList(QStringLiteral("applications"));
    for (const auto& a : list) {
        NotifyingApplication app = a.value<NotifyingApplication>();
        if (!m_applications.contains(app.name))
            m_applications.insert(app.name, app);
    }
    //qCDebug(KDECONNECT_PLUGIN_SENDNOTIFICATION) << "Loaded" << applications.size() << " applications";
}

bool NotificationsListener::parseImageDataArgument(const QVariant& argument,
                                                   int& width, int& height,
                                                   int& rowStride, int& bitsPerSample,
                                                   int& channels, bool& hasAlpha,
                                                   QByteArray& imageData) const
{
    if (!argument.canConvert<QDBusArgument>())
        return false;
    const QDBusArgument dbusArg = argument.value<QDBusArgument>();
    dbusArg.beginStructure();
    dbusArg >> width >> height >> rowStride >> hasAlpha >> bitsPerSample
            >> channels  >> imageData;
    dbusArg.endStructure();
    return true;
}

QSharedPointer<QIODevice> NotificationsListener::iconForImageData(const QVariant& argument) const
{
    int width, height, rowStride, bitsPerSample, channels;
    bool hasAlpha;
    QByteArray imageData;

    if (!parseImageDataArgument(argument, width, height, rowStride, bitsPerSample,
                                channels, hasAlpha, imageData))
        return QSharedPointer<QIODevice>();

    if (bitsPerSample != 8) {
        qCWarning(KDECONNECT_PLUGIN_SENDNOTIFICATION) << "Unsupported image format:"
                                                      << "width=" << width
                                                      << "height=" << height
                                                      << "rowStride=" << rowStride
                                                      << "bitsPerSample=" << bitsPerSample
                                                      << "channels=" << channels
                                                      << "hasAlpha=" << hasAlpha;
        return QSharedPointer<QIODevice>();
    }

    QImage image(reinterpret_cast<uchar*>(imageData.data()), width, height, rowStride,
                 hasAlpha ? QImage::Format_ARGB32 : QImage::Format_RGB32);
    if (hasAlpha)
        image = image.rgbSwapped();  // RGBA --> ARGB

    QSharedPointer<QBuffer> buffer = QSharedPointer<QBuffer>(new QBuffer);
    if (!buffer || !buffer->open(QIODevice::WriteOnly) ||
            !image.save(buffer.data(), "PNG")) {
        qCWarning(KDECONNECT_PLUGIN_SENDNOTIFICATION) << "Could not initialize image buffer";
        return QSharedPointer<QIODevice>();
    }

    return buffer;
}

QSharedPointer<QIODevice> NotificationsListener::iconForIconName(const QString& iconName) const
{
    int size = KIconLoader::SizeEnormous;  // use big size to allow for good
                                           // quality on high-DPI mobile devices
    QString iconPath = KIconLoader::global()->iconPath(iconName, -size, true);
    if (!iconPath.isEmpty()) {
        if (!iconPath.endsWith(QLatin1String(".png")) &&
                KIconLoader::global()->theme()->name() != QLatin1String("hicolor")) {
            // try falling back to hicolor theme:
            KIconTheme hicolor(QStringLiteral("hicolor"));
            if (hicolor.isValid()) {
                iconPath = hicolor.iconPath(iconName + ".png", size, KIconLoader::MatchBest);
                //qCDebug(KDECONNECT_PLUGIN_SENDNOTIFICATION) << "Found non-png icon in default theme trying fallback to hicolor:" << iconPath;
            }
        }
    }

    if (iconPath.endsWith(QLatin1String(".png")))
        return QSharedPointer<QIODevice>(new QFile(iconPath));
    return QSharedPointer<QIODevice>();
}

uint NotificationsListener::Notify(const QString& appName, uint replacesId,
                                   const QString& appIcon,
                                   const QString& summary, const QString& body,
                                   const QStringList& actions,
                                   const QVariantMap& hints, int timeout)
{
    static int id = 0;
    Q_UNUSED(actions);

    //qCDebug(KDECONNECT_PLUGIN_SENDNOTIFICATION) << "Got notification appName=" << appName << "replacesId=" << replacesId << "appIcon=" << appIcon << "summary=" << summary << "body=" << body << "actions=" << actions << "hints=" << hints << "timeout=" << timeout;

    // skip our own notifications
    if (appName == m_translatedAppName)
        return 0;

    NotifyingApplication app;
    if (!m_applications.contains(appName)) {
        // new application -> add to config
        app.name = appName;
        app.icon = appIcon;
        app.active = true;
        app.blacklistExpression = QRegularExpression();
        m_applications.insert(app.name, app);
        // update config:
        QVariantList list;
        for (const auto& a : qAsConst(m_applications))
            list << QVariant::fromValue<NotifyingApplication>(a);
        m_plugin->config()->setList(QStringLiteral("applications"), list);
        //qCDebug(KDECONNECT_PLUGIN_SENDNOTIFICATION) << "Added new application to config:" << app;
    } else
        app = m_applications.value(appName);

    if (!app.active)
        return 0;

    if (timeout > 0 && m_plugin->config()->get(QStringLiteral("generalPersistent"), false))
        return 0;

    int urgency = -1;
    if (hints.contains(QStringLiteral("urgency"))) {
        bool ok;
        urgency = hints[QStringLiteral("urgency")].toInt(&ok);
        if (!ok)
            urgency = -1;
    }
    if (urgency > -1 && urgency < m_plugin->config()->get<int>(QStringLiteral("generalUrgency"), 0))
        return 0;

    QString ticker = summary;
    if (!body.isEmpty() && m_plugin->config()->get(QStringLiteral("generalIncludeBody"), true))
        ticker += QStringLiteral(": ") + body;

    if (app.blacklistExpression.isValid() &&
            !app.blacklistExpression.pattern().isEmpty() &&
            app.blacklistExpression.match(ticker).hasMatch())
        return 0;

    //qCDebug(KDECONNECT_PLUGIN_SENDNOTIFICATION) << "Sending notification from" << appName << ":" <<ticker << "; appIcon=" << appIcon;
    NetworkPacket np(PACKET_TYPE_NOTIFICATION, {
        {"id", QString::number(replacesId > 0 ? replacesId : ++id)},
        {"appName", appName},
        {"ticker", ticker},
        {"isClearable", timeout == 0}
    });                                   // KNotifications are persistent if
                                          // timeout == 0, for other notifications
                                          // clearability is pointless

    // sync any icon data?
    if (m_plugin->config()->get(QStringLiteral("generalSynchronizeIcons"), true)) {
        QSharedPointer<QIODevice> iconSource;
        // try different image sources according to priorities in notifications-
        // spec version 1.2:
        if (hints.contains(QStringLiteral("image-data")))
            iconSource = iconForImageData(hints[QStringLiteral("image-data")]);
        else if (hints.contains(QStringLiteral("image_data")))  // 1.1 backward compatibility
            iconSource = iconForImageData(hints[QStringLiteral("image_data")]);
        else if (hints.contains(QStringLiteral("image-path")))
            iconSource = iconForIconName(hints[QStringLiteral("image-path")].toString());
        else if (hints.contains(QStringLiteral("image_path")))  // 1.1 backward compatibility
            iconSource = iconForIconName(hints[QStringLiteral("image_path")].toString());
        else if (!appIcon.isEmpty())
            iconSource = iconForIconName(appIcon);
        else if (hints.contains(QStringLiteral("icon_data")))  // < 1.1 backward compatibility
            iconSource = iconForImageData(hints[QStringLiteral("icon_data")]);

        if (iconSource)
            np.setPayload(iconSource, iconSource->size());
    }

    m_plugin->sendPacket(np);

    return (replacesId > 0 ? replacesId : id);
}