/**
 * Copyright 2013 Albert Vaca <albertvaka@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) 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 "mpriscontrolplugin.h"

#include <QDBusArgument>
#include <QDBusConnection>
#include <QDBusInterface>
#include <qdbusconnectioninterface.h>
#include <QDBusReply>
#include <QDBusMessage>
#include <QDBusServiceWatcher>

#include <KPluginFactory>

#include <core/device.h>
#include "mprisdbusinterface.h"
#include "propertiesdbusinterface.h"

K_PLUGIN_FACTORY_WITH_JSON( KdeConnectPluginFactory, "kdeconnect_mpriscontrol.json", registerPlugin< MprisControlPlugin >(); )

Q_LOGGING_CATEGORY(KDECONNECT_PLUGIN_MPRIS, "kdeconnect.plugin.mpris")


MprisPlayer::MprisPlayer(const QString& serviceName, const QString& dbusObjectPath, const QDBusConnection& busConnection)
    : m_serviceName(serviceName)
    , m_propertiesInterface(new OrgFreedesktopDBusPropertiesInterface(serviceName, dbusObjectPath, busConnection))
    , m_mediaPlayer2PlayerInterface(new OrgMprisMediaPlayer2PlayerInterface(serviceName, dbusObjectPath, busConnection))
{
    m_mediaPlayer2PlayerInterface->setTimeout(500);
}


MprisControlPlugin::MprisControlPlugin(QObject* parent, const QVariantList& args)
    : KdeConnectPlugin(parent, args)
    , prevVolume(-1)
{
    m_watcher = new QDBusServiceWatcher(QString(), QDBusConnection::sessionBus(), QDBusServiceWatcher::WatchForOwnerChange, this);

    // TODO: QDBusConnectionInterface::serviceOwnerChanged is deprecated, maybe query org.freedesktop.DBus directly?
    connect(QDBusConnection::sessionBus().interface(), &QDBusConnectionInterface::serviceOwnerChanged, this, &MprisControlPlugin::serviceOwnerChanged);

    //Add existing interfaces
    const QStringList services = QDBusConnection::sessionBus().interface()->registeredServiceNames().value();
    for (const QString& service : services) {
        // The string doesn't matter, it just needs to be empty/non-empty
        serviceOwnerChanged(service, QLatin1String(""), QStringLiteral("1"));
    }
}

// Copied from the mpris2 dataengine in the plasma-workspace repository
void MprisControlPlugin::serviceOwnerChanged(const QString& serviceName, const QString& oldOwner, const QString& newOwner)
{
    if (!serviceName.startsWith(QLatin1String("org.mpris.MediaPlayer2.")))
        return;

    if (!oldOwner.isEmpty()) {
        qCDebug(KDECONNECT_PLUGIN_MPRIS) << "MPRIS service" << serviceName << "just went offline";
        removePlayer(serviceName);
    }

    if (!newOwner.isEmpty()) {
        qCDebug(KDECONNECT_PLUGIN_MPRIS) << "MPRIS service" << serviceName << "just came online";
        addPlayer(serviceName);
    }
}


void MprisControlPlugin::addPlayer(const QString& service)
{
    const QString mediaPlayerObjectPath = QStringLiteral("/org/mpris/MediaPlayer2");

    // estimate identifier string
    QDBusInterface mprisInterface(service, mediaPlayerObjectPath, QStringLiteral("org.mpris.MediaPlayer2"));
    //FIXME: This call hangs and returns an empty string if KDED is still starting!
    QString identity = mprisInterface.property("Identity").toString();
    if (identity.isEmpty()) {
        identity = service.mid(sizeof("org.mpris.MediaPlayer2"));
    }

    QString uniqueName = identity;
    for (int i = 2; playerList.contains(uniqueName); ++i) {
        uniqueName = identity + QLatin1String(" [") + QString::number(i) + QLatin1Char(']');
    }

    MprisPlayer player(service, mediaPlayerObjectPath, QDBusConnection::sessionBus());

    playerList.insert(uniqueName, player);

    connect(player.propertiesInterface(), &OrgFreedesktopDBusPropertiesInterface::PropertiesChanged,
            this, &MprisControlPlugin::propertiesChanged);
    connect(player.mediaPlayer2PlayerInterface(), &OrgMprisMediaPlayer2PlayerInterface::Seeked,
            this, &MprisControlPlugin::seeked);

    qCDebug(KDECONNECT_PLUGIN_MPRIS) << "Mpris addPlayer" << service << "->" << uniqueName;
    sendPlayerList();
}

void MprisControlPlugin::seeked(qlonglong position){
    //qCDebug(KDECONNECT_PLUGIN_MPRIS) << "Seeked in player";
    OrgMprisMediaPlayer2PlayerInterface* mediaPlayer2PlayerInterface = (OrgMprisMediaPlayer2PlayerInterface*)sender();
    const auto end = playerList.constEnd();
    const auto it = std::find_if(playerList.constBegin(), end, [mediaPlayer2PlayerInterface](const MprisPlayer& player) {
        return (player.mediaPlayer2PlayerInterface() == mediaPlayer2PlayerInterface);
    });
    if (it == end) {
        qCWarning(KDECONNECT_PLUGIN_MPRIS) << "Seeked signal received for no longer tracked service" << mediaPlayer2PlayerInterface->service();
        return;
    }

    const QString& playerName = it.key();

    NetworkPacket np(PACKET_TYPE_MPRIS, {
        {"pos", position/1000}, //Send milis instead of nanos
        {"player", playerName}
    });
    sendPacket(np);
}

void MprisControlPlugin::propertiesChanged(const QString& propertyInterface, const QVariantMap& properties)
{
    Q_UNUSED(propertyInterface);

    OrgFreedesktopDBusPropertiesInterface* propertiesInterface = (OrgFreedesktopDBusPropertiesInterface*)sender();
    const auto end = playerList.constEnd();
    const auto it = std::find_if(playerList.constBegin(), end, [propertiesInterface](const MprisPlayer& player) {
        return (player.propertiesInterface() == propertiesInterface);
    });
    if (it == end) {
        qCWarning(KDECONNECT_PLUGIN_MPRIS) << "PropertiesChanged signal received for no longer tracked service" << propertiesInterface->service();
        return;
    }

    OrgMprisMediaPlayer2PlayerInterface* const mediaPlayer2PlayerInterface = it.value().mediaPlayer2PlayerInterface();
    const QString& playerName = it.key();

    NetworkPacket np(PACKET_TYPE_MPRIS);
    bool somethingToSend = false;
    if (properties.contains(QStringLiteral("Volume"))) {
        int volume = (int) (properties[QStringLiteral("Volume")].toDouble()*100);
        if (volume != prevVolume) {
            np.set(QStringLiteral("volume"),volume);
            prevVolume = volume;
            somethingToSend = true;
        }
    }
    if (properties.contains(QStringLiteral("Metadata"))) {
        QDBusArgument bullshit = qvariant_cast<QDBusArgument>(properties[QStringLiteral("Metadata")]);
        QVariantMap nowPlayingMap;
        bullshit >> nowPlayingMap;

        mprisPlayerMetadataToNetworkPacket(np, nowPlayingMap);
        somethingToSend = true;
    }
    if (properties.contains(QStringLiteral("PlaybackStatus"))) {
        bool playing = (properties[QStringLiteral("PlaybackStatus")].toString() == QLatin1String("Playing"));
        np.set(QStringLiteral("isPlaying"), playing);
        somethingToSend = true;
    }
    if (properties.contains(QStringLiteral("CanPause"))) {
        np.set(QStringLiteral("canPause"), properties[QStringLiteral("CanPause")].toBool());
        somethingToSend = true;
    }
    if (properties.contains(QStringLiteral("CanPlay"))) {
        np.set(QStringLiteral("canPlay"), properties[QStringLiteral("CanPlay")].toBool());
        somethingToSend = true;
    }
    if (properties.contains(QStringLiteral("CanGoNext"))) {
        np.set(QStringLiteral("canGoNext"), properties[QStringLiteral("CanGoNext")].toBool());
        somethingToSend = true;
    }
    if (properties.contains(QStringLiteral("CanGoPrevious"))) {
        np.set(QStringLiteral("canGoPrevious"), properties[QStringLiteral("CanGoPrevious")].toBool());
        somethingToSend = true;
    }
    if (properties.contains(QStringLiteral("CanSeek"))) {
        np.set(QStringLiteral("canSeek"), properties[QStringLiteral("CanSeek")].toBool());
        somethingToSend = true;
    }

    if (somethingToSend) {
        np.set(QStringLiteral("player"), playerName);
        // Always also update the position
        if (mediaPlayer2PlayerInterface->canSeek()) {
            long long pos = mediaPlayer2PlayerInterface->position();
            np.set(QStringLiteral("pos"), pos/1000); //Send milis instead of nanos
        }
        sendPacket(np);
    }
}

void MprisControlPlugin::removePlayer(const QString& serviceName)
{
    const auto end = playerList.end();
    const auto it = std::find_if(playerList.begin(), end, [serviceName](const MprisPlayer& player) {
        return (player.serviceName() == serviceName);
    });
    if (it == end) {
        qCWarning(KDECONNECT_PLUGIN_MPRIS) << "Could not find player for serviceName" << serviceName;
        return;
    }

    const QString& playerName = it.key();
    qCDebug(KDECONNECT_PLUGIN_MPRIS) << "Mpris removePlayer" << serviceName << "->" << playerName;

    playerList.erase(it);

    sendPlayerList();
}

bool MprisControlPlugin::sendAlbumArt(const NetworkPacket& np)
{
    const QString player = np.get<QString>(QStringLiteral("player"));
    auto it = playerList.find(player);
    bool valid_player = (it != playerList.end());
    if (!valid_player) {
        return false;
    }

    //Get mpris information
    auto& mprisInterface = *it.value().mediaPlayer2PlayerInterface();
    QVariantMap nowPlayingMap = mprisInterface.metadata();

    //Check if the supplied album art url indeed belongs to this mpris player
    QUrl playerAlbumArtUrl{nowPlayingMap[QStringLiteral("mpris:artUrl")].toString()};
    QString requestedAlbumArtUrl = np.get<QString>(QStringLiteral("albumArtUrl"));
    if (!playerAlbumArtUrl.isValid() || playerAlbumArtUrl != QUrl(requestedAlbumArtUrl)) {
        return false;
    }

    //Only support sending local files
    if (playerAlbumArtUrl.scheme() != "file") {
        return false;
    }

    //Open the file to send
    QSharedPointer<QFile> art{new QFile(playerAlbumArtUrl.toLocalFile())};

    //Send the album art as payload
    NetworkPacket answer(PACKET_TYPE_MPRIS);
    answer.set(QStringLiteral("transferringAlbumArt"), true);
    answer.set(QStringLiteral("player"), player);
    answer.set(QStringLiteral("albumArtUrl"), requestedAlbumArtUrl);
    answer.setPayload(art, art->size());
    sendPacket(answer);
    return true;
}

bool MprisControlPlugin::receivePacket (const NetworkPacket& np)
{
    if (np.has(QStringLiteral("playerList"))) {
        return false; //Whoever sent this is an mpris client and not an mpris control!
    }

    if (np.has(QStringLiteral("albumArtUrl"))) {
        return sendAlbumArt(np);
    }

    //Send the player list
    const QString player = np.get<QString>(QStringLiteral("player"));
    auto it = playerList.find(player);
    bool valid_player = (it != playerList.end());
    if (!valid_player || np.get<bool>(QStringLiteral("requestPlayerList"))) {
        sendPlayerList();
        if (!valid_player) {
            return true;
        }
    }

    //Do something to the mpris interface
    const QString& serviceName = it.value().serviceName();
    // turn from pointer to reference to keep the patch diff small,
    // actual patch would change all "mprisInterface." into "mprisInterface->"
    auto& mprisInterface = *it.value().mediaPlayer2PlayerInterface();
    if (np.has(QStringLiteral("action"))) {
        const QString& action = np.get<QString>(QStringLiteral("action"));
        //qCDebug(KDECONNECT_PLUGIN_MPRIS) << "Calling action" << action << "in" << serviceName;
        //TODO: Check for valid actions, currently we trust anything the other end sends us
        mprisInterface.call(action);
    }
    if (np.has(QStringLiteral("setVolume"))) {
        double volume = np.get<int>(QStringLiteral("setVolume"))/100.f;
        qCDebug(KDECONNECT_PLUGIN_MPRIS) << "Setting volume" << volume << "to" << serviceName;
        mprisInterface.setVolume(volume);
    }
    if (np.has(QStringLiteral("Seek"))) {
        int offset = np.get<int>(QStringLiteral("Seek"));
        //qCDebug(KDECONNECT_PLUGIN_MPRIS) << "Seeking" << offset << "to" << serviceName;
        mprisInterface.Seek(offset);
    }

    if (np.has(QStringLiteral("SetPosition"))){
        qlonglong position = np.get<qlonglong>(QStringLiteral("SetPosition"),0)*1000;
        qlonglong seek = position - mprisInterface.position();
        //qCDebug(KDECONNECT_PLUGIN_MPRIS) << "Setting position by seeking" << seek << "to" << serviceName;
        mprisInterface.Seek(seek);
    }

    //Send something read from the mpris interface
    NetworkPacket answer(PACKET_TYPE_MPRIS);
    bool somethingToSend = false;
    if (np.get<bool>(QStringLiteral("requestNowPlaying"))) {
        QVariantMap nowPlayingMap = mprisInterface.metadata();
        mprisPlayerMetadataToNetworkPacket(answer, nowPlayingMap);

        qlonglong pos = mprisInterface.position();
        answer.set(QStringLiteral("pos"), pos/1000);

        bool playing = (mprisInterface.playbackStatus() == QLatin1String("Playing"));
        answer.set(QStringLiteral("isPlaying"), playing);

        answer.set(QStringLiteral("canPause"), mprisInterface.canPause());
        answer.set(QStringLiteral("canPlay"), mprisInterface.canPlay());
        answer.set(QStringLiteral("canGoNext"), mprisInterface.canGoNext());
        answer.set(QStringLiteral("canGoPrevious"), mprisInterface.canGoPrevious());
        answer.set(QStringLiteral("canSeek"), mprisInterface.canSeek());

        somethingToSend = true;
    }
    if (np.get<bool>(QStringLiteral("requestVolume"))) {
        int volume = (int)(mprisInterface.volume() * 100);
        answer.set(QStringLiteral("volume"),volume);
        somethingToSend = true;
    }

    if (somethingToSend) {
        answer.set(QStringLiteral("player"), player);
        sendPacket(answer);
    }

    return true;
}

void MprisControlPlugin::sendPlayerList()
{
    NetworkPacket np(PACKET_TYPE_MPRIS);
    np.set(QStringLiteral("playerList"),playerList.keys());
    np.set(QStringLiteral("supportAlbumArtPayload"), true);
    sendPacket(np);
}

void MprisControlPlugin::mprisPlayerMetadataToNetworkPacket(NetworkPacket& np, const QVariantMap& nowPlayingMap) const {
    QString title = nowPlayingMap[QStringLiteral("xesam:title")].toString();
    QString artist = nowPlayingMap[QStringLiteral("xesam:artist")].toString();
    QString album = nowPlayingMap[QStringLiteral("xesam:album")].toString();
    QString albumArtUrl = nowPlayingMap[QStringLiteral("mpris:artUrl")].toString();
    QString nowPlaying = title;
    if (!artist.isEmpty()) {
        nowPlaying = artist + " - " + title;
    }
    np.set(QStringLiteral("title"), title);
    np.set(QStringLiteral("artist"), artist);
    np.set(QStringLiteral("album"), album);
    np.set(QStringLiteral("albumArtUrl"), albumArtUrl);
    np.set(QStringLiteral("nowPlaying"), nowPlaying);

    bool hasLength = false;
    long long length = nowPlayingMap[QStringLiteral("mpris:length")].toLongLong(&hasLength) / 1000; //nanoseconds to milliseconds
    if (!hasLength) {
        length = -1;
    }
    np.set(QStringLiteral("length"), length);
}

#include "mpriscontrolplugin.moc"
