// SPDX-License-Identifier: GPL-3.0-only
/*
 *  PolyMC - Minecraft Launcher
 *  Copyright (C) 2022 Sefa Eyeoglu <contact@scrumplex.net>
 *
 *  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, version 3.
 *
 *  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 <https://www.gnu.org/licenses/>.
 *
 * This file incorporates work covered by the following copyright and
 * permission notice:
 *
 *      Copyright 2013-2021 MultiMC Contributors
 *
 *      Licensed under the Apache License, Version 2.0 (the "License");
 *      you may not use this file except in compliance with the License.
 *      You may obtain a copy of the License at
 *
 *          http://www.apache.org/licenses/LICENSE-2.0
 *
 *      Unless required by applicable law or agreed to in writing, software
 *      distributed under the License is distributed on an "AS IS" BASIS,
 *      WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 *      See the License for the specific language governing permissions and
 *      limitations under the License.
 */

#include "VersionProxyModel.h"
#include "Application.h"
#include <QSortFilterProxyModel>
#include <QPixmapCache>
#include <Version.h>
#include <meta/VersionList.h>

class VersionFilterModel : public QSortFilterProxyModel
{
    Q_OBJECT
public:
    VersionFilterModel(VersionProxyModel *parent) : QSortFilterProxyModel(parent)
    {
        m_parent = parent;
        setSortRole(BaseVersionList::SortRole);
        sort(0, Qt::DescendingOrder);
    }

    bool filterAcceptsRow(int source_row, const QModelIndex &source_parent) const
    {
        const auto &filters = m_parent->filters();
        for (auto it = filters.begin(); it != filters.end(); ++it)
        {
            auto idx = sourceModel()->index(source_row, 0, source_parent);
            auto data = sourceModel()->data(idx, it.key());
            auto match = data.toString();
            if(!it.value()->accepts(match))
            {
                return false;
            }
        }
        return true;
    }

    void filterChanged()
    {
        invalidateFilter();
    }
private:
    VersionProxyModel *m_parent;
};

VersionProxyModel::VersionProxyModel(QObject *parent) : QAbstractProxyModel(parent)
{
    filterModel = new VersionFilterModel(this);
    connect(filterModel, &QAbstractItemModel::dataChanged, this, &VersionProxyModel::sourceDataChanged);
    connect(filterModel, &QAbstractItemModel::rowsAboutToBeInserted, this, &VersionProxyModel::sourceRowsAboutToBeInserted);
    connect(filterModel, &QAbstractItemModel::rowsInserted, this, &VersionProxyModel::sourceRowsInserted);
    connect(filterModel, &QAbstractItemModel::rowsAboutToBeRemoved, this, &VersionProxyModel::sourceRowsAboutToBeRemoved);
    connect(filterModel, &QAbstractItemModel::rowsRemoved, this, &VersionProxyModel::sourceRowsRemoved);
    // FIXME: implement when needed
    /*
    connect(replacing, &QAbstractItemModel::rowsAboutToBeMoved, this, &VersionProxyModel::sourceRowsAboutToBeMoved);
    connect(replacing, &QAbstractItemModel::rowsMoved, this, &VersionProxyModel::sourceRowsMoved);
    connect(replacing, &QAbstractItemModel::layoutAboutToBeChanged, this, &VersionProxyModel::sourceLayoutAboutToBeChanged);
    connect(replacing, &QAbstractItemModel::layoutChanged, this, &VersionProxyModel::sourceLayoutChanged);
    */
    connect(filterModel, &QAbstractItemModel::modelAboutToBeReset, this, &VersionProxyModel::sourceAboutToBeReset);
    connect(filterModel, &QAbstractItemModel::modelReset, this, &VersionProxyModel::sourceReset);

    QAbstractProxyModel::setSourceModel(filterModel);
}

QVariant VersionProxyModel::headerData(int section, Qt::Orientation orientation, int role) const
{
    if(section < 0 || section >= m_columns.size())
        return QVariant();
    if(orientation != Qt::Horizontal)
        return QVariant();
    auto column = m_columns[section];
    if(role == Qt::DisplayRole)
    {
        switch(column)
        {
            case Name:
                return tr("Version");
            case ParentVersion:
                return tr("Minecraft"); //FIXME: this should come from metadata
            case Branch:
                return tr("Branch");
            case Type:
                return tr("Type");
            case Architecture:
                return tr("Architecture");
            case Path:
                return tr("Path");
            case Time:
                return tr("Released");
        }
    }
    else if(role == Qt::ToolTipRole)
    {
        switch(column)
        {
            case Name:
                return tr("The name of the version.");
            case ParentVersion:
                return tr("Minecraft version"); //FIXME: this should come from metadata
            case Branch:
                return tr("The version's branch");
            case Type:
                return tr("The version's type");
            case Architecture:
                return tr("CPU Architecture");
            case Path:
                return tr("Filesystem path to this version");
            case Time:
                return tr("Release date of this version");
        }
    }
    return QVariant();
}

QVariant VersionProxyModel::data(const QModelIndex &index, int role) const
{
    if(!index.isValid())
    {
        return QVariant();
    }
    auto column = m_columns[index.column()];
    auto parentIndex = mapToSource(index);
    switch(role)
    {
        case Qt::DisplayRole:
        {
            switch(column)
            {
                case Name:
                {
                    QString version = sourceModel()->data(parentIndex, BaseVersionList::VersionRole).toString();
                    if(version == m_currentVersion)
                    {
                        return tr("%1 (installed)").arg(version);
                    }
                    return version;
                }
                case ParentVersion:
                    return sourceModel()->data(parentIndex, BaseVersionList::ParentVersionRole);
                case Branch:
                    return sourceModel()->data(parentIndex, BaseVersionList::BranchRole);
                case Type:
                    return sourceModel()->data(parentIndex, BaseVersionList::TypeRole);
                case Architecture:
                    return sourceModel()->data(parentIndex, BaseVersionList::ArchitectureRole);
                case Path:
                    return sourceModel()->data(parentIndex, BaseVersionList::PathRole);
                case Time:
                    return sourceModel()->data(parentIndex, Meta::VersionList::TimeRole).toDate();
                default:
                    return QVariant();
            }
        }
        case Qt::ToolTipRole:
        {
            if(column == Name && hasRecommended) 
            {
                auto value = sourceModel()->data(parentIndex, BaseVersionList::RecommendedRole);
                if(value.toBool())
                {
                    return tr("Recommended");
                } else if(hasLatest) {
                    auto value = sourceModel()->data(parentIndex, BaseVersionList::LatestRole);
                    if(value.toBool())
                    {
                        return tr("Latest");
                    }
                } else if(index.row() == 0)
                {
                    return tr("Latest");
                }
            } else {
                return sourceModel()->data(parentIndex, BaseVersionList::VersionIdRole);
            }
        }
        case Qt::DecorationRole:
        {
            switch(column)
            {
                case Name:
                {
                    if(hasRecommended)
                    {
                        auto value = sourceModel()->data(parentIndex, BaseVersionList::RecommendedRole);
                        if(value.toBool())
                        {
                            return APPLICATION->getThemedIcon("star");
                        }
                        else if(hasLatest)
                        {
                            auto value = sourceModel()->data(parentIndex, BaseVersionList::LatestRole);
                            if(value.toBool())
                            {
                                return APPLICATION->getThemedIcon("bug");
                            }
                        }
                        else if(index.row() == 0)
                        {
                            return APPLICATION->getThemedIcon("bug");
                        }
                        QPixmap pixmap;
                        QPixmapCache::find("placeholder", &pixmap);
                        if(!pixmap)
                        {
                            QPixmap px(16,16);
                            px.fill(Qt::transparent);
                            QPixmapCache::insert("placeholder", px);
                            return px;
                        }
                        return pixmap;
                    }
                }
                default:
                {
                    return QVariant();
                }
            }
        }
        default:
        {
            if(roles.contains((BaseVersionList::ModelRoles)role))
            {
                return sourceModel()->data(parentIndex, role);
            }
            return QVariant();
        }
    }
}

QModelIndex VersionProxyModel::parent(const QModelIndex &child) const
{
    return QModelIndex();
}

QModelIndex VersionProxyModel::mapFromSource(const QModelIndex &sourceIndex) const
{
    if(sourceIndex.isValid())
    {
        return index(sourceIndex.row(), 0);
    }
    return QModelIndex();
}

QModelIndex VersionProxyModel::mapToSource(const QModelIndex &proxyIndex) const
{
    if(proxyIndex.isValid())
    {
        return sourceModel()->index(proxyIndex.row(), 0);
    }
    return QModelIndex();
}

QModelIndex VersionProxyModel::index(int row, int column, const QModelIndex &parent) const
{
    // no trees here... shoo
    if(parent.isValid())
    {
        return QModelIndex();
    }
    if(row < 0 || row >= sourceModel()->rowCount())
        return QModelIndex();
    if(column < 0 || column >= columnCount())
        return QModelIndex();
    return QAbstractItemModel::createIndex(row, column);
}

int VersionProxyModel::columnCount(const QModelIndex &parent) const
{
    return parent.isValid() ? 0 : m_columns.size();
}

int VersionProxyModel::rowCount(const QModelIndex &parent) const
{
    if(sourceModel())
    {
        return sourceModel()->rowCount(parent);
    }
    return 0;
}

void VersionProxyModel::sourceDataChanged(const QModelIndex &source_top_left,
                                          const QModelIndex &source_bottom_right)
{
    if(source_top_left.parent() != source_bottom_right.parent())
        return;

    // whole row is getting changed
    auto topLeft = createIndex(source_top_left.row(), 0);
    auto bottomRight = createIndex(source_bottom_right.row(), columnCount() - 1);
    emit dataChanged(topLeft, bottomRight);
}

void VersionProxyModel::setSourceModel(QAbstractItemModel *replacingRaw)
{
    auto replacing = dynamic_cast<BaseVersionList *>(replacingRaw);
    beginResetModel();

    m_columns.clear();
    if(!replacing)
    {
        roles.clear();
        filterModel->setSourceModel(replacing);
        return;
    }

    roles = replacing->providesRoles();
    if(roles.contains(BaseVersionList::VersionRole))
    {
        m_columns.push_back(Name);
    }
    /*
    if(roles.contains(BaseVersionList::ParentVersionRole))
    {
        m_columns.push_back(ParentVersion);
    }
    */
    if(roles.contains(BaseVersionList::ArchitectureRole))
    {
        m_columns.push_back(Architecture);
    }
    if(roles.contains(BaseVersionList::PathRole))
    {
        m_columns.push_back(Path);
    }
    if(roles.contains(Meta::VersionList::TimeRole))
    {
        m_columns.push_back(Time);
    }
    if(roles.contains(BaseVersionList::BranchRole))
    {
        m_columns.push_back(Branch);
    }
    if(roles.contains(BaseVersionList::TypeRole))
    {
        m_columns.push_back(Type);
    }
    if(roles.contains(BaseVersionList::RecommendedRole))
    {
        hasRecommended = true;
    }
    if(roles.contains(BaseVersionList::LatestRole))
    {
        hasLatest = true;
    }
    filterModel->setSourceModel(replacing);

    endResetModel();
}

QModelIndex VersionProxyModel::getRecommended() const
{
    if(!roles.contains(BaseVersionList::RecommendedRole))
    {
        return index(0, 0);
    }
    int recommended = 0;
    for (int i = 0; i < rowCount(); i++)
    {
        auto value = sourceModel()->data(mapToSource(index(i, 0)), BaseVersionList::RecommendedRole);
        if (value.toBool())
        {
            recommended = i;
        }
    }
    return index(recommended, 0);
}

QModelIndex VersionProxyModel::getVersion(const QString& version) const
{
    int found = -1;
    for (int i = 0; i < rowCount(); i++)
    {
        auto value = sourceModel()->data(mapToSource(index(i, 0)), BaseVersionList::VersionRole);
        if (value.toString() == version)
        {
            found = i;
        }
    }
    if(found == -1)
    {
        return QModelIndex();
    }
    return index(found, 0);
}

void VersionProxyModel::clearFilters()
{
    m_filters.clear();
    filterModel->filterChanged();
}

void VersionProxyModel::setFilter(const BaseVersionList::ModelRoles column, Filter * f)
{
    m_filters[column].reset(f);
    filterModel->filterChanged();
}

const VersionProxyModel::FilterMap &VersionProxyModel::filters() const
{
    return m_filters;
}

void VersionProxyModel::sourceAboutToBeReset()
{
    beginResetModel();
}

void VersionProxyModel::sourceReset()
{
    endResetModel();
}

void VersionProxyModel::sourceRowsAboutToBeInserted(const QModelIndex& parent, int first, int last)
{
    beginInsertRows(parent, first, last);
}

void VersionProxyModel::sourceRowsInserted(const QModelIndex& parent, int first, int last)
{
    endInsertRows();
}

void VersionProxyModel::sourceRowsAboutToBeRemoved(const QModelIndex& parent, int first, int last)
{
    beginRemoveRows(parent, first, last);
}

void VersionProxyModel::sourceRowsRemoved(const QModelIndex& parent, int first, int last)
{
    endRemoveRows();
}

void VersionProxyModel::setCurrentVersion(const QString &version)
{
    m_currentVersion = version;
}

#include "VersionProxyModel.moc"