/*
 * Copyright (c) 2008 Sander Knopper (sander AT knopper DOT tk) and
 *                    Roeland Douma (roeland AT rullzer DOT com)
 *
 * This file is part of QtMPC.
 *
 * QtMPC 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.
 *
 * QtMPC 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 QtMPC.  If not, see <http://www.gnu.org/licenses/>.
 */

#include "mpdconnection.h"
#include "mpdparseutils.h"
#ifdef ENABLE_KDE_SUPPORT
#include <KDE/KMessageBox>
#include <KDE/KLocale>
#include <KDE/KGlobal>
#else
#include <QtGui/QMessageBox>
#endif
#include <QtGui/QApplication>

//#undef qDebug
//#define qDebug qWarning

#ifdef ENABLE_KDE_SUPPORT
K_GLOBAL_STATIC(MPDConnection, conn)
#endif

MPDConnection * MPDConnection::self()
{
#ifdef ENABLE_KDE_SUPPORT
    return conn;
#else
    static MPDConnection *conn=0;;
    if(!conn) {
        conn=new MPDConnection;
    }
    return conn;
#endif
}

static QByteArray readFromSocket(QTcpSocket &socket)
{
    QByteArray data;

    while (socket.state() == QAbstractSocket::ConnectedState) {
        while (socket.bytesAvailable() == 0 && socket.state() == QAbstractSocket::ConnectedState) {
            qDebug("MPDConnection: waiting for read data.");
            if (socket.waitForReadyRead(5000)) {
                break;
            }
        }

        data.append(socket.readAll());

        if (data.endsWith("OK\n") || data.startsWith("OK") || data.startsWith("ACK")) {
            break;
        }
    }
    if(data.size()>128) {
        qDebug() << "Read (bytes):" << data.size();
    } else {
        qDebug() << "Read:" << data;
    }

    return data;
}

MPDConnection::Response readReply(QTcpSocket &socket)
{
    QByteArray data = readFromSocket(socket);
    return MPDConnection::Response(data.endsWith("OK\n"), data);
}

MPDConnection::MPDConnection()
{
    connect(&sock, SIGNAL(stateChanged(QAbstractSocket::SocketState)), this, SLOT(onSocketStateChanged(QAbstractSocket::SocketState)));
    connect(&idleSocket, SIGNAL(stateChanged(QAbstractSocket::SocketState)), this, SLOT(onIdleSocketStateChanged(QAbstractSocket::SocketState)));
}

MPDConnection::~MPDConnection()
{
    disconnect(&sock, SIGNAL(stateChanged(QAbstractSocket::SocketState)), this, SLOT(onSocketStateChanged(QAbstractSocket::SocketState)));
    disconnect(&idleSocket, SIGNAL(stateChanged(QAbstractSocket::SocketState)), this, SLOT(onIdleSocketStateChanged(QAbstractSocket::SocketState)));

    sock.disconnectFromHost();
    idleSocket.disconnectFromHost();
    quit();

    while (isRunning())
        msleep(100);
}

bool MPDConnection::connectToMPD(QTcpSocket &socket, bool enableIdle)
{
    if (socket.state() != QAbstractSocket::ConnectedState) {
        qDebug() << "Connecting" << enableIdle;
        if (hostname.isEmpty() || port == 0) {
            qDebug("MPDConnection: no hostname and/or port supplied.");
            return false;
        }

        socket.connectToHost(hostname, port);
        if (socket.waitForConnected(5000)) {
            qDebug("MPDConnectionBase established");
            QByteArray recvdata = readFromSocket(socket);

            if (recvdata.startsWith("OK MPD")) {
                qDebug("Received identification string");
            }

            recvdata.clear();

            if (!password.isEmpty()) {
                qWarning("MPDConnection: setting password...");
                QByteArray senddata = "password ";
                senddata += password.toUtf8();
                senddata += "\n";
                socket.write(senddata);
                socket.waitForBytesWritten(5000);
                if (readReply(socket).ok) {
                    qDebug("MPDConnection: password accepted");
                } else {
                    qDebug("MPDConnection: password rejected");
                }
            }

            if(enableIdle) {
                connect(&socket, SIGNAL(readyRead()), this, SLOT(idleDataReady()));
                qDebug() << "Enabling idle";
                socket.write("idle\n");
                socket.waitForBytesWritten();
            }
            return true;
        } else {
            qDebug("Couldn't connect");
            return false;
        }
    }

    qDebug() << "Already connected" << enableIdle;
    return true;
}

bool MPDConnection::connectToMPD()
{
    return connectToMPD(sock) && connectToMPD(idleSocket, true);
}

void MPDConnection::disconnectFromMPD()
{
    sock.disconnectFromHost();
    idleSocket.disconnectFromHost();
}

void MPDConnection::setDetails(const QString &host, const quint16 p, const QString &pass)
{
    // TODO: If diff, then reconnect!
    hostname=host;
    port=p;
    password=pass;
}

bool MPDConnection::isConnected()
{
    return (sock.state() == QAbstractSocket::ConnectedState);
}

MPDConnection::Response MPDConnection::sendCommand(const QByteArray &command)
{
    if (!connectToMPD()) {
        return Response();
    }

    mutex.lock();

    qDebug() << "command: " << command;

    sock.write(command);
    sock.write("\n");
    sock.waitForBytesWritten(5000);
    Response response=readReply(sock);

    mutex.unlock();
    return response;
}

/*
 * Playlist commands
 */

void MPDConnection::add(const QStringList &files)
{
    QByteArray send = "command_list_begin\n";

    for (int i = 0; i < files.size(); i++) {
        send += "add \"";
        send += files.at(i).toUtf8();
        send += "\"\n";
    }

    send += "command_list_end";

    if (!sendCommand(send).ok){
        qDebug("Couldn't add song(s) to playlist");
    }
}

/**
 * Add all the files in the QStringList to the playlist at
 * postition post.
 *
 * NOTE: addid is not fully supported in < 0.14 So add everything
 * and then move everything to the right spot.
 *
 * @param files A QStringList with all the files to add
 * @param pos Position to add the files
 * @param size The size of the current playlist
 */
void MPDConnection::addid(const QStringList &files, const quint32 pos, const quint32 size)
{
    QByteArray send = "command_list_begin\n";
    int cur_size = size;
    for (int i = 0; i < files.size(); i++) {
        send += "add \"";
        send += files.at(i).toUtf8();
        send += "\"";
        send += "\n";
        send += "move ";
        send += QByteArray::number(cur_size);
        send += " ";
        send += QByteArray::number(pos);
        send += "\n";
        cur_size++;
    }

    send += "command_list_end";

    if (!sendCommand(send).ok) {
        qDebug("Couldn't add song(s) to playlist");
    }
}

void MPDConnection::clear()
{
    if(sendCommand("clear").ok) {
        qDebug("Couldn't clear playlist");
    }
}

void MPDConnection::removeSongs(const QList<qint32> &items)
{
    QByteArray send = "command_list_begin\n";

    for (int i = 0; i < items.size(); i++) {
        send += "deleteid ";
        send += QByteArray::number(items.at(i));
        send += "\n";
    }

    send += "command_list_end";

    if (!sendCommand(send).ok) {
        qDebug("Couldn't remove songs from playlist");
    }
}

void MPDConnection::move(const quint32 from, const quint32 to)
{
    QByteArray send = "move " + QByteArray::number(from) + " " + QByteArray::number(to);

    qWarning() << send;
    if (!sendCommand(send).ok) {
        qDebug("Couldn't move files around in playlist");
    }
}

void MPDConnection::move(const QList<quint32> items, const quint32 pos, const quint32 size)
{
    QByteArray send = "command_list_begin\n";
    QList<quint32> moveItems;

    moveItems.append(items);
    qSort(moveItems);

    int posOffset = 0;

    //first move all items (starting with the biggest) to the end so we don't have to deal with changing rownums
    for (int i = moveItems.size() - 1; i >= 0; i--) {
        if (moveItems.at(i) < pos && moveItems.at(i) != size - 1) {
            // we are moving away an item that resides before the destinatino row, manipulate destination row
            posOffset++;
        }
        send += "move ";
        send += QByteArray::number(moveItems.at(i));
        send += " ";
        send += QByteArray::number(size - 1);
        send += "\n";
    }
    //now move all of them to the destination position
    for (int i = moveItems.size() - 1; i >= 0; i--) {
        send += "move ";
        send += QByteArray::number(size - 1 - i);
        send += " ";
        send += QByteArray::number(pos - posOffset);
        send += "\n";
    }

    send += "command_list_end";

    if (!sendCommand(send).ok) {
        qDebug("Couldn't move songs around in playlist");
    }
}

void MPDConnection::shuffle()
{
    if (!sendCommand("shuffle").ok) {
        qDebug("Couldn't shuffle playlist");
    }
}

void MPDConnection::shuffle(const quint32 from, const quint32 to)
{
    QByteArray command = "shuffle ";
    command += QByteArray::number(from);
    command += ":";
    command += QByteArray::number(to + 1);

    if (!sendCommand(command).ok) {
        qDebug("Couldn't shuffle playlist");
    }
}

void MPDConnection::currentSong()
{
    Response response=sendCommand("currentsong");
    if(response.ok) {
        emit currentSongUpdated(MPDParseUtils::parseSong(response.data));
    }
}

void MPDConnection::playListInfo()
{
    Response response=sendCommand("playlistinfo");
    if(response.ok) {
        emit playlistUpdated(MPDParseUtils::parseSongs(response.data));
    }
}

/*
 * Playback commands
 */
void MPDConnection::setCrossFade(const quint8 secs)
{
    QByteArray data = "crossfade ";
    data += QByteArray::number(secs);
    if (!sendCommand(data).ok) {
        qDebug("Couldn't set xfade");
    }
}

void MPDConnection::setReplayGain(const QString &v)
{
    QByteArray data = "replay_gain_mode ";
    data += v.toLatin1();
    if (!sendCommand(data).ok) {
        qDebug("Couldn't set replay_gain_mode");
    }
}

QString MPDConnection::getReplayGain()
{
    QStringList lines=QString(sendCommand("replay_gain_status").data).split('\n', QString::SkipEmptyParts);

    if (2==lines.count() && "OK"==lines[1] && lines[0].startsWith(QLatin1String("replay_gain_mode: "))) {
        return lines[0].mid(18);
    }

    return QString();
}

void MPDConnection::goToNext()
{
    if (!sendCommand("next").ok) {
        qDebug("Couldn't go to next track");
    }
}

void MPDConnection::setPause(const bool toggle)
{
    QByteArray data = "pause ";
    if (toggle == true)
        data += "1";
    else
        data += "0";

    if (!sendCommand(data).ok) {
        qDebug("Couldn't set pause");
    }
}

void MPDConnection::startPlayingSong(const quint32 song)
{
    QByteArray data = "play ";
    data += QByteArray::number(song);
    if (!sendCommand(data).ok) {
        qDebug("Couldn't start playing song");
    }
}

void MPDConnection::startPlayingSongId(const quint32 song_id)
{
    QByteArray data = "playid ";
    data += QByteArray::number(song_id);
    if (!sendCommand(data).ok) {
        qDebug("Couldn't start playing song id");
    }
}

void MPDConnection::goToPrevious()
{
    if (!sendCommand("previous").ok) {
        qDebug("Couldn't go to previous track");
    }
}

void MPDConnection::setConsume(const bool toggle)
{
    QByteArray data = "consume ";
    if (toggle == true)
        data += "1";
    else
        data += "0";

    if (!sendCommand(data).ok) {
        qDebug("Couldn't toggle consume");
    }
}

void MPDConnection::setRandom(const bool toggle)
{
    QByteArray data = "random ";
    if (toggle == true)
        data += "1";
    else
        data += "0";

    if (!sendCommand(data).ok) {
        qDebug("Couldn't toggle random");
    }
}

void MPDConnection::setRepeat(const bool toggle)
{
    QByteArray data = "repeat ";
    if (toggle == true)
        data += "1";
    else
        data += "0";

    if (!sendCommand(data).ok) {
        qDebug("Couldn't toggle repeat");
    }
}

void MPDConnection::setSeek(const quint32 song, const quint32 time)
{
    QByteArray data = "seek ";
    data += QByteArray::number(song);
    data += " ";
    data += QByteArray::number(time);

    if (!sendCommand(data).ok) {
        qDebug("Couldn't set seek position");
    }
}

void MPDConnection::setSeekId(const quint32 song_id, const quint32 time)
{
    QByteArray data = "seekid ";
    data += QByteArray::number(song_id);
    data += " ";
    data += QByteArray::number(time);
    if (!sendCommand(data).ok) {
        qDebug("Couldn't set seek position");
    }
}

void MPDConnection::setVolume(const quint8 vol)
{
    QByteArray data = "setvol ";
    data += QByteArray::number(vol);
    if (!sendCommand(data).ok) {
        qDebug("Couldn't set volume");
    }
}

void MPDConnection::stopPlaying()
{
    if (!sendCommand("stop").ok) {
        qDebug("Couldn't stop playing");
    }
}

void MPDConnection::getStats()
{
    Response response=sendCommand("stats");
    if(response.ok) {
        MPDParseUtils::parseStats(response.data);
        emit statsUpdated();
    }
}

void MPDConnection::getStatus()
{
    Response response=sendCommand("status");
    if(response.ok) {
        MPDParseUtils::parseStatus(response.data);
        emit statusUpdated();
    }
}

/*
 * Data is written during idle.
 * Retrieve it and parse it
 */
void MPDConnection::idleDataReady()
{
    qDebug() << "idleDataReady";
    QByteArray data;

    if (idleSocket.bytesAvailable() == 0) {
        return;
    }

    parseIdleReturn(readFromSocket(idleSocket));
    idleSocket.write("idle\n");
    idleSocket.waitForBytesWritten();
}

/*
 * Socket state has changed, currently we only use this to gracefully
 * handle disconnects.
 */
void MPDConnection::onSocketStateChanged(QAbstractSocket::SocketState socketState)
{
    if (socketState == QAbstractSocket::ClosingState){
    //    emit mpdConnectionDied();
        sock.disconnectFromHost();
        connectToMPD(sock);
    }
}

void MPDConnection::onIdleSocketStateChanged(QAbstractSocket::SocketState socketState)
{
    if (socketState == QAbstractSocket::ClosingState){
        idleSocket.disconnectFromHost();
        connectToMPD(idleSocket);
    }
}

/*
 * Parse data returned by the mpd deamon on an idle commond.
 */
void MPDConnection::parseIdleReturn(const QByteArray &data)
{
    qDebug() << "parseIdleReturn:" << data;
    QList<QByteArray> lines = data.split('\n');

    QByteArray line;

    /*
     * See http://www.musicpd.org/doc/protocol/ch02.html
     */
    foreach(line, lines) {
        if (line == "changed: database") {
            /*
             * Temp solution
             */
            getStats();
        } else if (line == "changed: update") {
            emit databaseUpdated();
        } else if (line == "changed: stored_playlist") {
            emit storedPlayListUpdated();
        } else if (line == "changed: playlist") {
            playListInfo();
        } else if (line == "changed: player") {
            getStatus();
        } else if (line == "changed: mixer") {
            getStatus();
        } else if (line == "changed: output") {
            outputs();
        } else if (line == "changed: options") {
            getStatus();
        } else if (line == "OK") {
            break;
        } else {
            qWarning() << "Unknown command in idle return: " << line;
        }
    }
}

void MPDConnection::outputs()
{
    Response response=sendCommand("outputs");
    if(response.ok) {
        emit outputsUpdated(MPDParseUtils::parseOuputs(response.data));
    }
}

void MPDConnection::enableOutput(const quint8 id)
{
    QByteArray data = "enableoutput ";
    data += QByteArray::number(id);
    if (!sendCommand(data).ok) {
        qDebug("Couldn't enable output");
    }
}

void MPDConnection::disableOutput(const quint8 id)
{
    QByteArray data = "disableoutput ";
    data += QByteArray::number(id);
    if (!sendCommand(data).ok) {
        qDebug("Couldn't disable output");
    }
}

/*
 * Admin commands
 */
void MPDConnection::update()
{
    sendCommand("update");
}

/*
 * Database commands
 */

/**
 * Get all files in the playlist with detailed info (artist, album,
 * title, time etc).
 *
 * @param db_update The last update time of the library
 */
void MPDConnection::listAllInfo(QDateTime db_update)
{
    Response response=sendCommand("listallinfo");
    if(response.ok) {
        qDebug() << "parseLibraryItems:" << response.data;
        emit musicLibraryUpdated(MPDParseUtils::parseLibraryItems(response.data), db_update);
    }
}

/**
* Get all the files and dir in the mpdmusic dir.
*
*/
void MPDConnection::listAll()
{
    Response response=sendCommand("listall");
    if(response.ok) {
        emit dirViewUpdated(MPDParseUtils::parseDirViewItems(response.data));
    }
}

/*
 * Playlists commands
 */
void MPDConnection::listPlaylist()
{
    sendCommand("listplaylist");
}

void MPDConnection::listPlaylists()
{
    Response response=sendCommand("listplaylists");
    if(response.ok) {
        emit playlistsRetrieved(MPDParseUtils::parsePlaylists(response.data));
    }
}

void MPDConnection::load(QString name)
{
    QByteArray data("load ");
    data += "\"" + name.toUtf8().replace("\\", "\\\\").replace("\"", "\\\"") + "\"";

    if (!sendCommand(data).ok) {
        qDebug("Couldn't load playlist");
    }
}

void MPDConnection::rename(const QString oldName, const QString newName)
{
    QByteArray data("rename ");
    data += "\"" + oldName.toUtf8().replace("\\", "\\\\").replace("\"", "\\\"") + "\"";
    data += " ";
    data += "\"" + newName.toUtf8().replace("\\", "\\\\").replace("\"", "\\\"") + "\"";

    if (!sendCommand(data).ok) {
        qDebug("Couldn't rename playlist");
    }
}

void MPDConnection::rm(QString name)
{
    QByteArray data("rm ");
    data += "\"" + name.toUtf8().replace("\\", "\\\\").replace("\"", "\\\"") + "\"";

    if (!sendCommand(data).ok) {
        qDebug("Couldn't remove playlist");
    }
}

void MPDConnection::save(QString name)
{
    QByteArray data("save ");
    data += "\"" + name.toUtf8().replace("\\", "\\\\").replace("\"", "\\\"") + "\"";

    Response response = sendCommand(data);
    if (!response.ok && response.data.endsWith("Playlist already exists\n")) {
        #ifdef ENABLE_KDE_SUPPORT
        if (KMessageBox::Yes==KMessageBox::warningYesNo(QApplication::activeWindow(), i18n("A Playlist named <i>%1</i> already exists!<br/>Overwrite?").arg(name))) {
            rm(name);
            response = sendCommand(data);
            if (!response.ok) {
                KMessageBox::error(QApplication::activeWindow(), i18n("Failed to save playlist."));
            }
        }
        #else
        // TODO: Prompt user as per KDE version...
        QMessageBox::warning(QApplication::activeWindow(), "Warning", "Playlist couldn't be saved since there already exists a playlist with the same name.");
        #endif
    }
}