/*
    Copyright 2010 Rafael Fernández López <ereslibre@kde.org>
              2010 Lukas Tinkl <ltinkl@redhat.com>
              2011 Matej Laitl <matej@laitl.cz>

    This library is free software; you can redistribute it and/or
    modify it under the terms of the GNU Lesser General Public
    License as published by the Free Software Foundation; either
    version 2.1 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 6 of version 3 of the license.

    This library 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
    Lesser General Public License for more details.

    You should have received a copy of the GNU Lesser General Public
    License along with this library. If not, see <http://www.gnu.org/licenses/>.
*/

#include "udevportablemediaplayer.h"

#include <QChar>
#include <QDebug>
#include <QFile>
#include <QTextStream>
#include <qstandardpaths.h>

using namespace Solid::Backends::UDev;

/**
 * Reads one value from media-player-info ini-like file.
 *
 * @param file file to open. May advance current seek position
 * @param group group name to read from, e.g. "Device" for [Device] group
 * @param key key name, e.g. "AccessProtocol"
 * @return value as a string or an empty string
 */
static QString readMpiValue(QIODevice &file, const QString &group, const QString &key)
{
    QTextStream mpiStream(&file);
    QString line;
    QString currGroup;

    while (!mpiStream.atEnd()) {
        line = mpiStream.readLine().trimmed();  // trimmed is needed for possible indentation
        if (line.isEmpty() || line.startsWith(QChar(';'))) {
            // skip empty and comment lines
        } else if (line.startsWith(QChar('[')) && line.endsWith(QChar(']'))) {
            currGroup = line.mid(1, line.length() - 2);  // strip [ and ]
        } else if (line.indexOf(QChar('=')) != -1) {
            int index = line.indexOf(QChar('='));
            if (currGroup == group && line.left(index) == key) {
                line = line.right(line.length() - index - 1);
                if (line.startsWith(QChar('"')) && line.endsWith(QChar('"'))) {
                    line = line.mid(1, line.length() - 2);  // strip enclosing double quotes
                }
                return line;
            }
        } else {
            qWarning() << "readMpiValue: cannot parse line:" << line;
        }
    }
    return QString();
}

PortableMediaPlayer::PortableMediaPlayer(UDevDevice *device)
    : DeviceInterface(device)
{

}

PortableMediaPlayer::~PortableMediaPlayer()
{

}

QStringList PortableMediaPlayer::supportedProtocols() const
{
    /* There are multiple packages that set ID_MEDIA_PLAYER:
     *  * gphoto2 sets it to numeric 1 (for _some_ cameras it supports) and it hopefully
     *    means MTP-compatible device.
     *  * libmtp >= 1.0.4 sets it to numeric 1 and this always denotes MTP-compatible player.
     *  * media-player-info sets it to a string that denotes a name of the .mpi file with
     *    additional info.
     */
    if (m_device->property("ID_MEDIA_PLAYER").toInt() == 1) {
        return QStringList() << "mtp";
    }

    QString mpiFileName = mediaPlayerInfoFilePath();
    if (mpiFileName.isEmpty()) {
        return QStringList();
    }
    // we unfornutately cannot use QSettings as it cannot read unquoted valued with semicolons in it
    QFile mpiFile(mpiFileName);
    if (!mpiFile.open(QIODevice::ReadOnly | QIODevice::Text)) {
        qWarning() << "Cannot open" << mpiFileName << "for reading."
                   << "Check your media-player-info installation.";
        return QStringList();
    }
    QString value = readMpiValue(mpiFile, QString("Device"), QString("AccessProtocol"));
    return value.split(QChar(';'), QString::SkipEmptyParts);
}

QStringList PortableMediaPlayer::supportedDrivers(QString protocol) const
{
    Q_UNUSED(protocol)
    QStringList res;

    if (!supportedProtocols().isEmpty()) {
        res << "usb";
    }
    if (m_device->property("USBMUX_SUPPORTED").toBool() == true) {
        res << "usbmux";
    }
    return res;
}

QVariant PortableMediaPlayer::driverHandle(const QString &driver) const
{
    if (driver == "mtp" || driver == "usbmux") {
        return m_device->property("ID_SERIAL_SHORT");
    }

    return QVariant();
}

QString PortableMediaPlayer::mediaPlayerInfoFilePath() const
{
    QString relativeFilename = m_device->property("ID_MEDIA_PLAYER").toString();
    if (relativeFilename.isEmpty()) {
        qWarning() << "We attached PortableMediaPlayer interface to device" << m_device->udi()
                   << "but m_device->property(\"ID_MEDIA_PLAYER\") is empty???";
        return QString();
    }
    relativeFilename.prepend("media-player-info/");
    relativeFilename.append(".mpi");
    QString filename = QStandardPaths::locate(QStandardPaths::GenericDataLocation, relativeFilename);
    if (filename.isEmpty()) {
        qWarning() << "media player info file" << relativeFilename << "not found under user and"
                   << "system XDG data directories. Do you have media-player-info installed?";
    }
    return filename;
}
