/***************************************************************************
 *   Copyright (C) 2008 Fredrik Höglund <fredrik@kde.org>                  *
 *   Copyright (C) 2014 by Eike Hein <hein@kde.org>                        *
 *                                                                         *
 *   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, write to the                         *
 *   Free Software Foundation, Inc.,                                       *
 *   51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA .        *
 ***************************************************************************/

#include "previewpluginsmodel.h"

#include <KServiceTypeTrader>

#include <KIO/PreviewJob>

#include <algorithm>

static bool lessThan(const KService::Ptr &a, const KService::Ptr &b)
{
    return QString::localeAwareCompare(a->name(), b->name()) < 0;
}

PreviewPluginsModel::PreviewPluginsModel(QObject *parent)
    : QAbstractListModel(parent)
{
    m_plugins = KServiceTypeTrader::self()->query(QStringLiteral("ThumbCreator"));
    qStableSort(m_plugins.begin(), m_plugins.end(), lessThan);

    m_checkedRows = QVector<bool>(m_plugins.size(), false);
}

PreviewPluginsModel::~PreviewPluginsModel()
{
}

QHash<int, QByteArray> PreviewPluginsModel::roleNames() const
{
    return {
        { Qt::DisplayRole, "display" },
        { Qt::CheckStateRole, "checked" }
    };
}

QVariant PreviewPluginsModel::data(const QModelIndex &index, int role) const
{
    if (index.row() < 0 || index.row() >= m_plugins.size()) {
        return QVariant();
    }

    switch (role) {
        case Qt::DisplayRole:
            return m_plugins.at(index.row())->name();

        case Qt::CheckStateRole:
            return m_checkedRows.at(index.row()) ? Qt::Checked : Qt::Unchecked;
    }

    return QVariant();
}

bool PreviewPluginsModel::setData(const QModelIndex &index, const QVariant &value, int role)
{
    if (index.row() < 0 || index.row() >= m_plugins.size()) {
        return false;
    }

    if (role == Qt::CheckStateRole) {
        m_checkedRows[index.row()] = value.toBool();
        emit dataChanged(index, index, {role});
        return true;
    }

    return false;
}

int PreviewPluginsModel::indexOfPlugin(const QString &name) const
{
    for (int i = 0; i < m_plugins.size(); i++) {
        if (m_plugins.at(i)->desktopEntryName() == name) {
            return i;
        }
    }
    return -1;
}

void PreviewPluginsModel::setCheckedPlugins(const QStringList &list)
{
    QStringList plugins = list;
    if (plugins.isEmpty()) {
        plugins = KIO::PreviewJob::defaultPlugins();
    }

    m_checkedRows = QVector<bool>(m_plugins.size(), false);

    for (const QString &name : plugins) {
        const int row = indexOfPlugin(name);
        if (row != -1) {
            m_checkedRows[row] = true;
        }
    }

    emit dataChanged(index(0, 0), index(m_plugins.size() - 1, 0), {Qt::CheckStateRole});

    emit checkedPluginsChanged();
}

QStringList PreviewPluginsModel::checkedPlugins() const
{
    QStringList list;
    for (int i = 0; i < m_checkedRows.size(); ++i) {
        if (m_checkedRows.at(i)) {
            list.append(m_plugins.at(i)->desktopEntryName());
        }
    }

    const QStringList defaultPlugins = KIO::PreviewJob::defaultPlugins();

    // If the list of checked plugins is the default set, return an empty list
    // which denotes the default set.
    // This ensures newly installed thumbnails are always automatically enabled.
    if (std::is_permutation(list.constBegin(), list.constEnd(), defaultPlugins.begin())) {
        return QStringList();
    }

    return list;
}
