/*******************************************************************************
 * Copyright (C) 2016 Ragnar Thomsen <rthomsen6@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, see <http://www.gnu.org/licenses/>.              *
 *******************************************************************************/

#include "unitmodel.h"

#include <KLocalizedString>
#include <KColorScheme>

#include <QColor>
#include <QIcon>
#include <QtDBus/QtDBus>

#include <systemd/sd-journal.h>

UnitModel::UnitModel(QObject *parent)
    : QAbstractTableModel(parent)
{
}

UnitModel::UnitModel(QObject *parent, const QVector<SystemdUnit> *list, QString userBusPath)
    : QAbstractTableModel(parent)
{
    m_unitList = list;
    m_userBus = userBusPath;
}

int UnitModel::rowCount(const QModelIndex &) const
{
    return m_unitList->size();
}

int UnitModel::columnCount(const QModelIndex &) const
{
    return 4;
}

QVariant UnitModel::headerData(int section, Qt::Orientation orientation, int role) const
{
    if (orientation == Qt::Horizontal && role == Qt::DisplayRole && section == 0) {
        return i18n("Unit");
    } else if (orientation == Qt::Horizontal && role == Qt::DisplayRole && section == 1) {
        return i18n("Load State");
    } else if (orientation == Qt::Horizontal && role == Qt::DisplayRole && section == 2) {
        return i18n("Active State");
    } else if (orientation == Qt::Horizontal && role == Qt::DisplayRole && section == 3) {
        return i18n("Unit State");
    }
    return QVariant();
}

QVariant UnitModel::data(const QModelIndex & index, int role) const
{

    if (!index.isValid()) {
        return QVariant();
    }

    if (role == Qt::DisplayRole)
    {
        if (index.column() == 0)
            return m_unitList->at(index.row()).id;
        else if (index.column() == 1)
            return m_unitList->at(index.row()).load_state;
        else if (index.column() == 2)
            return m_unitList->at(index.row()).active_state;
        else if (index.column() == 3)
            return m_unitList->at(index.row()).sub_state;
    }

    else if (role == Qt::ForegroundRole)
    {
        const KColorScheme scheme(QPalette::Normal);
        if (m_unitList->at(index.row()).active_state == QLatin1String("active"))
            return scheme.foreground(KColorScheme::PositiveText);
        else if (m_unitList->at(index.row()).active_state == QLatin1String("failed"))
            return scheme.foreground(KColorScheme::NegativeText);
        else if (m_unitList->at(index.row()).active_state == QLatin1String("-"))
            return scheme.foreground(KColorScheme::InactiveText);
        else
            return QVariant();
    }

    else if (role == Qt::DecorationRole)
    {
        if (index.column() == 0) {
            if (m_unitList->at(index.row()).active_state == QLatin1String("active")) {
                return QIcon::fromTheme(QStringLiteral("emblem-success"));
            } else if (m_unitList->at(index.row()).active_state == QLatin1String("inactive")) {
                return QIcon::fromTheme(QStringLiteral("emblem-pause"));
            } else if (m_unitList->at(index.row()).active_state == QLatin1String("failed")) {
                return QIcon::fromTheme(QStringLiteral("emblem-error"));
            } else if (m_unitList->at(index.row()).active_state == QLatin1String("-")) {
                return QIcon::fromTheme(QStringLiteral("emblem-unavailable"));
            } else {
                return QVariant();
            }
        }
    }

    else if (role == Qt::ToolTipRole)
    {
        const QString selUnit = m_unitList->at(index.row()).id;
        const QString selUnitPath = m_unitList->at(index.row()).unit_path.path();
        const QString selUnitFile = m_unitList->at(index.row()).unit_file;

        QString toolTipText;
        toolTipText.append(QStringLiteral("<b>%1</b><hr>").arg(selUnit));

        // Create a DBus interface
        QDBusConnection bus(QDBusConnection::systemBus());
        if (!m_userBus.isEmpty()) {
            bus = QDBusConnection::connectToBus(m_userBus, QStringLiteral("org.freedesktop.systemd1"));
        }
        QDBusInterface *iface;

        // Use the DBus interface to get unit properties
        if (!selUnitPath.isEmpty())
        {
            // Unit has a valid path

            iface = new QDBusInterface (QStringLiteral("org.freedesktop.systemd1"),
                                        selUnitPath,
                                        QStringLiteral("org.freedesktop.systemd1.Unit"),
                                        bus);
            if (iface->isValid())
            {
                // Unit has a valid unit DBus object
                toolTipText.append(i18n("<b>Description: </b>"));
                toolTipText.append(iface->property("Description").toString());

                const QString unitFilePath = iface->property("FragmentPath").toString();
                if (!unitFilePath.isEmpty()) {
                    toolTipText.append(i18n("<br><b>Unit file: </b>%1", unitFilePath));
                    toolTipText.append(i18n("<br><b>Unit file state: </b>"));
                    toolTipText.append(iface->property("UnitFileState").toString());
                }

                const QString sourcePath = iface->property("SourcePath").toString();
                if (!sourcePath.isEmpty()) {
                    toolTipText.append(i18n("<br><b>Source path: </b>%1", sourcePath));
                }

                qulonglong ActiveEnterTimestamp = iface->property("ActiveEnterTimestamp").toULongLong();
                toolTipText.append(i18n("<br><b>Activated: </b>"));
                if (ActiveEnterTimestamp == 0)
                    toolTipText.append(QStringLiteral("n/a"));
                else
                {
                    QDateTime timeActivated;
                    timeActivated.setMSecsSinceEpoch(ActiveEnterTimestamp/1000);
                    toolTipText.append(timeActivated.toString());
                }

                qulonglong InactiveEnterTimestamp = iface->property("InactiveEnterTimestamp").toULongLong();
                toolTipText.append(i18n("<br><b>Deactivated: </b>"));
                if (InactiveEnterTimestamp == 0)
                    toolTipText.append(QStringLiteral("n/a"));
                else
                {
                    QDateTime timeDeactivated;
                    timeDeactivated.setMSecsSinceEpoch(InactiveEnterTimestamp/1000);
                    toolTipText.append(timeDeactivated.toString());
                }
            }
            delete iface;

        } else {

            // Unit does not have a valid unit DBus object (typically unloaded units).
            // Retrieve UnitFileState from Manager object.

            iface = new QDBusInterface (QStringLiteral("org.freedesktop.systemd1"),
                                        QStringLiteral("/org/freedesktop/systemd1"),
                                        QStringLiteral("org.freedesktop.systemd1.Manager"),
                                        bus);
            QList<QVariant> args;
            args << selUnit;

            toolTipText.append(i18n("<b>Unit file: </b>"));
            if (!selUnitFile.isEmpty()) {
                toolTipText.append(selUnitFile);
            }

            toolTipText.append(i18n("<br><b>Unit file state: </b>"));
            if (!selUnitFile.isEmpty()) {
                toolTipText.append(iface->callWithArgumentList(QDBus::AutoDetect, QStringLiteral("GetUnitFileState"), args).arguments().at(0).toString());
            }

            delete iface;
        }

        // Journal entries for units
        toolTipText.append(i18n("<hr><b>Last log entries:</b>"));
        QStringList log = getLastJrnlEntries(selUnit);
        if (log.isEmpty()) {
            toolTipText.append(i18n("<br><i>No log entries found for this unit.</i>"));
        } else {
            for(int i = log.count()-1; i >= 0; --i)
            {
                if (!log.at(i).isEmpty())
                    toolTipText.append(QStringLiteral("<br>%1").arg(log.at(i)));
            }
        }

        toolTipText.append(QStringLiteral("</FONT"));

        return toolTipText;
    }

    return QVariant();
}

QStringList UnitModel::getLastJrnlEntries(QString unit) const
{
    QString match1, match2;
    int r, jflags;
    QStringList reply;
    const void *data;
    size_t length;
    uint64_t time;
    sd_journal *journal;

    if (!m_userBus.isEmpty())
    {
        match1 = QStringLiteral("USER_UNIT=%1").arg(unit);
        jflags = (SD_JOURNAL_LOCAL_ONLY | SD_JOURNAL_CURRENT_USER);
    }
    else
    {
        match1 = QStringLiteral("_SYSTEMD_UNIT=%1").arg(unit);
        match2 = QStringLiteral("UNIT=%1").arg(unit);
        jflags = (SD_JOURNAL_LOCAL_ONLY | SD_JOURNAL_SYSTEM);
    }

    r = sd_journal_open(&journal, jflags);
    if (r != 0)
    {
        qDebug() << "Failed to open journal";
        return reply;
    }

    sd_journal_flush_matches(journal);

    r = sd_journal_add_match(journal, match1.toUtf8().constData(), 0);
    if (r != 0)
        return reply;

    if (!match2.isEmpty())
    {
        sd_journal_add_disjunction(journal);
        r = sd_journal_add_match(journal, match2.toUtf8().constData(), 0);
        if (r != 0)
            return reply;
    }


    r = sd_journal_seek_tail(journal);
    if (r != 0)
        return reply;

    // Fetch the last 5 entries
    for (int i = 0; i < 5; ++i)
    {
        r = sd_journal_previous(journal);
        if (r == 1)
        {
            QString line;

            // Get the date and time
            r = sd_journal_get_realtime_usec(journal, &time);
            if (r == 0)
            {
                QDateTime date;
                date.setMSecsSinceEpoch(time/1000);
                line.append(date.toString(QStringLiteral("yyyy.MM.dd hh:mm")));
            }

            // Color messages according to priority
            r = sd_journal_get_data(journal, "PRIORITY", &data, &length);
            if (r == 0)
            {
                int prio = QString::fromUtf8((const char *)data, length).section(QLatin1Char('='),1).toInt();
                if (prio <= 3)
                    line.append(QStringLiteral("<span style='color:tomato;'>"));
                else if (prio == 4)
                    line.append(QStringLiteral("<span style='color:khaki;'>"));
                else
                    line.append(QStringLiteral("<span style='color:palegreen;'>"));
            }

            // Get the message itself
            r = sd_journal_get_data(journal, "MESSAGE", &data, &length);
            if (r == 0)
            {
                line.append(QStringLiteral(": %1</span>").arg(QString::fromUtf8((const char *)data, length).section(QLatin1Char('='),1)));
                if (line.length() > 195)
                    line = QStringLiteral("%1...</span>").arg(line.left(195));
                reply << line;
            }
        }
        else // previous failed, no more entries
            return reply;
    }

    sd_journal_close(journal);

    return reply;
}
