/* SPDX-FileCopyrightText: 2026 Project Tick
 * SPDX-FileContributor: Project Tick
 * SPDX-License-Identifier: GPL-3.0-or-later WITH LicenseRef-MeshMC-MMCO-Module-Exception-1.0
 *
 *   MeshMC - A Custom Launcher for Minecraft
 *   Copyright (C) 2026 Project Tick
 *
 *   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 3 of the License, or
 *   (at your option) any later version, with the additional permission
 *   described in the MeshMC MMCO Module Exception 1.0.
 *
 *   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/>.
 *
 *   You should have received a copy of the MeshMC MMCO Module Exception 1.0
 *   along with this program.  If not, see <https://projecttick.org/licenses/>.
 */

#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: {
			switch (column) {
				case Name: {
					if (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");
						}
					}
				}
				default: {
					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;
						if (!QPixmapCache::find("placeholder", &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 m_columns.size();
}

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

	// Temporarily disconnect filterModel's reset signals so that the inner
	// filterModel->setSourceModel() call does not emit a second
	// modelAboutToBeReset / modelReset, which would cause our
	// beginResetModel / endResetModel to be called twice (once from here
	// and once from sourceAboutToBeReset / sourceReset). Qt prints
	// "beginResetModel called without endResetModel" in that case and the
	// model's internal state gets corrupted, leading to crashes.
	disconnect(filterModel, &QAbstractItemModel::modelAboutToBeReset, this,
			   &VersionProxyModel::sourceAboutToBeReset);
	disconnect(filterModel, &QAbstractItemModel::modelReset, this,
			   &VersionProxyModel::sourceReset);

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

	// Reconnect now that our own reset pair is done.
	connect(filterModel, &QAbstractItemModel::modelAboutToBeReset, this,
			&VersionProxyModel::sourceAboutToBeReset);
	connect(filterModel, &QAbstractItemModel::modelReset, this,
			&VersionProxyModel::sourceReset);
}

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"
