1 files changed, 573 insertions, 0 deletions
diff --git a/meshmc/launcher/minecraft/mod/ModFolderModel.cpp b/meshmc/launcher/minecraft/mod/ModFolderModel.cpp
new file mode 100644
index 0000000000..faaa814590
--- /dev/null
+++ b/meshmc/launcher/minecraft/mod/ModFolderModel.cpp
@@ -0,0 +1,573 @@
+/* SPDX-FileCopyrightText: 2026 Project Tick
+ * SPDX-FileContributor: Project Tick
+ * SPDX-License-Identifier: GPL-3.0-or-later
+ *
+ *   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.
+ *
+ *   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 "ModFolderModel.h"
+#include <FileSystem.h>
+#include <QMimeData>
+#include <QUrl>
+#include <QUuid>
+#include <QString>
+#include <QFileSystemWatcher>
+#include <QDebug>
+#include "ModFolderLoadTask.h"
+#include <QThreadPool>
+#include <algorithm>
+#include "LocalModParseTask.h"
+
+ModFolderModel::ModFolderModel(const QString& dir)
+	: QAbstractListModel(), m_dir(dir)
+{
+	FS::ensureFolderPathExists(m_dir.absolutePath());
+	m_dir.setFilter(QDir::Readable | QDir::NoDotAndDotDot | QDir::Files |
+					QDir::Dirs);
+	m_dir.setSorting(QDir::Name | QDir::IgnoreCase | QDir::LocaleAware);
+	m_watcher = new QFileSystemWatcher(this);
+	connect(m_watcher, SIGNAL(directoryChanged(QString)), this,
+			SLOT(directoryChanged(QString)));
+}
+
+void ModFolderModel::startWatching()
+{
+	if (is_watching)
+		return;
+
+	update();
+
+	is_watching = m_watcher->addPath(m_dir.absolutePath());
+	if (is_watching) {
+		qDebug() << "Started watching " << m_dir.absolutePath();
+	} else {
+		qDebug() << "Failed to start watching " << m_dir.absolutePath();
+	}
+}
+
+void ModFolderModel::stopWatching()
+{
+	if (!is_watching)
+		return;
+
+	is_watching = !m_watcher->removePath(m_dir.absolutePath());
+	if (!is_watching) {
+		qDebug() << "Stopped watching " << m_dir.absolutePath();
+	} else {
+		qDebug() << "Failed to stop watching " << m_dir.absolutePath();
+	}
+}
+
+bool ModFolderModel::update()
+{
+	if (!isValid()) {
+		return false;
+	}
+	if (m_update) {
+		scheduled_update = true;
+		return true;
+	}
+
+	auto task = new ModFolderLoadTask(m_dir);
+	m_update = task->result();
+	QThreadPool* threadPool = QThreadPool::globalInstance();
+	connect(task, &ModFolderLoadTask::succeeded, this,
+			&ModFolderModel::finishUpdate);
+	threadPool->start(task);
+	return true;
+}
+
+void ModFolderModel::finishUpdate()
+{
+	auto keys1 = modsIndex.keys();
+	QSet<QString> currentSet(keys1.begin(), keys1.end());
+	auto& newMods = m_update->mods;
+	auto keys2 = newMods.keys();
+	QSet<QString> newSet(keys2.begin(), keys2.end());
+
+	// see if the kept mods changed in some way
+	{
+		QSet<QString> kept = currentSet;
+		kept.intersect(newSet);
+		for (auto& keptMod : kept) {
+			auto& newMod = newMods[keptMod];
+			auto row = modsIndex[keptMod];
+			auto& currentMod = mods[row];
+			if (newMod.dateTimeChanged() == currentMod.dateTimeChanged()) {
+				// no significant change, ignore...
+				continue;
+			}
+			auto& oldMod = mods[row];
+			if (oldMod.isResolving()) {
+				activeTickets.remove(oldMod.resolutionTicket());
+			}
+			oldMod = newMod;
+			resolveMod(mods[row]);
+			emit dataChanged(index(row, 0),
+							 index(row, columnCount(QModelIndex()) - 1));
+		}
+	}
+
+	// remove mods no longer present
+	{
+		QSet<QString> removed = currentSet;
+		QList<int> removedRows;
+		removed.subtract(newSet);
+		for (auto& removedMod : removed) {
+			removedRows.append(modsIndex[removedMod]);
+		}
+		std::sort(removedRows.begin(), removedRows.end(), std::greater<int>());
+		for (auto iter = removedRows.begin(); iter != removedRows.end();
+			 iter++) {
+			int removedIndex = *iter;
+			beginRemoveRows(QModelIndex(), removedIndex, removedIndex);
+			auto removedIter = mods.begin() + removedIndex;
+			if (removedIter->isResolving()) {
+				activeTickets.remove(removedIter->resolutionTicket());
+			}
+			mods.erase(removedIter);
+			endRemoveRows();
+		}
+	}
+
+	// add new mods to the end
+	{
+		QSet<QString> added = newSet;
+		added.subtract(currentSet);
+		beginInsertRows(QModelIndex(), mods.size(),
+						mods.size() + added.size() - 1);
+		for (auto& addedMod : added) {
+			mods.append(newMods[addedMod]);
+			resolveMod(mods.last());
+		}
+		endInsertRows();
+	}
+
+	// update index
+	{
+		modsIndex.clear();
+		int idx = 0;
+		for (auto& mod : mods) {
+			modsIndex[mod.mmc_id()] = idx;
+			idx++;
+		}
+	}
+
+	m_update.reset();
+
+	emit updateFinished();
+
+	if (scheduled_update) {
+		scheduled_update = false;
+		update();
+	}
+}
+
+void ModFolderModel::resolveMod(Mod& m)
+{
+	if (!m.shouldResolve()) {
+		return;
+	}
+
+	auto task =
+		new LocalModParseTask(nextResolutionTicket, m.type(), m.filename());
+	auto result = task->result();
+	result->id = m.mmc_id();
+	activeTickets.insert(nextResolutionTicket, result);
+	m.setResolving(true, nextResolutionTicket);
+	nextResolutionTicket++;
+	QThreadPool* threadPool = QThreadPool::globalInstance();
+	connect(task, &LocalModParseTask::finished, this,
+			&ModFolderModel::finishModParse);
+	threadPool->start(task);
+}
+
+void ModFolderModel::finishModParse(int token)
+{
+	auto iter = activeTickets.find(token);
+	if (iter == activeTickets.end()) {
+		return;
+	}
+	auto result = *iter;
+	activeTickets.remove(token);
+	int row = modsIndex[result->id];
+	auto& mod = mods[row];
+	mod.finishResolvingWithDetails(result->details);
+	emit dataChanged(index(row), index(row, columnCount(QModelIndex()) - 1));
+}
+
+void ModFolderModel::disableInteraction(bool disabled)
+{
+	if (interaction_disabled == disabled) {
+		return;
+	}
+	interaction_disabled = disabled;
+	if (size()) {
+		emit dataChanged(index(0), index(size() - 1));
+	}
+}
+
+void ModFolderModel::directoryChanged(QString path)
+{
+	update();
+}
+
+bool ModFolderModel::isValid()
+{
+	return m_dir.exists() && m_dir.isReadable();
+}
+
+// FIXME: this does not take disabled mod (with extra .disable extension) into
+// account...
+bool ModFolderModel::installMod(const QString& filename)
+{
+	if (interaction_disabled) {
+		return false;
+	}
+
+	// NOTE: fix for GH-1178: remove trailing slash to avoid issues with using
+	// the empty result of QFileInfo::fileName
+	auto originalPath = FS::NormalizePath(filename);
+	QFileInfo fileinfo(originalPath);
+
+	if (!fileinfo.exists() || !fileinfo.isReadable()) {
+		qWarning() << "Caught attempt to install non-existing file or "
+					  "file-like object:"
+				   << originalPath;
+		return false;
+	}
+	qDebug() << "installing: " << fileinfo.absoluteFilePath();
+
+	Mod installedMod(fileinfo);
+	if (!installedMod.valid()) {
+		qDebug() << originalPath << "is not a valid mod. Ignoring it.";
+		return false;
+	}
+
+	auto type = installedMod.type();
+	if (type == Mod::MOD_UNKNOWN) {
+		qDebug() << "Cannot recognize mod type of" << originalPath
+				 << ", ignoring it.";
+		return false;
+	}
+
+	auto newpath =
+		FS::NormalizePath(FS::PathCombine(m_dir.path(), fileinfo.fileName()));
+	if (originalPath == newpath) {
+		qDebug() << "Overwriting the mod (" << originalPath
+				 << ") with itself makes no sense...";
+		return false;
+	}
+
+	if (type == Mod::MOD_SINGLEFILE || type == Mod::MOD_ZIPFILE ||
+		type == Mod::MOD_LITEMOD) {
+		if (QFile::exists(newpath) ||
+			QFile::exists(newpath + QString(".disabled"))) {
+			if (!QFile::remove(newpath)) {
+				// FIXME: report error in a user-visible way
+				qWarning() << "Copy from" << originalPath << "to" << newpath
+						   << "has failed.";
+				return false;
+			}
+			qDebug() << newpath << "has been deleted.";
+		}
+		if (!QFile::copy(fileinfo.filePath(), newpath)) {
+			qWarning() << "Copy from" << originalPath << "to" << newpath
+					   << "has failed.";
+			// FIXME: report error in a user-visible way
+			return false;
+		}
+		FS::updateTimestamp(newpath);
+		installedMod.repath(QFileInfo(newpath));
+		update();
+		return true;
+	} else if (type == Mod::MOD_FOLDER) {
+		QString from = fileinfo.filePath();
+		if (QFile::exists(newpath)) {
+			qDebug() << "Ignoring folder " << from << ", it would merge with "
+					 << newpath;
+			return false;
+		}
+
+		if (!FS::copy(from, newpath)()) {
+			qWarning() << "Copy of folder from" << originalPath << "to"
+					   << newpath << "has (potentially partially) failed.";
+			return false;
+		}
+		installedMod.repath(QFileInfo(newpath));
+		update();
+		return true;
+	}
+	return false;
+}
+
+bool ModFolderModel::setModStatus(const QModelIndexList& indexes,
+								  ModStatusAction enable)
+{
+	if (interaction_disabled) {
+		return false;
+	}
+
+	if (indexes.isEmpty())
+		return true;
+
+	for (auto index : indexes) {
+		if (index.column() != 0) {
+			continue;
+		}
+		setModStatus(index.row(), enable);
+	}
+	return true;
+}
+
+bool ModFolderModel::deleteMods(const QModelIndexList& indexes)
+{
+	if (interaction_disabled) {
+		return false;
+	}
+
+	if (indexes.isEmpty())
+		return true;
+
+	for (auto i : indexes) {
+		Mod& m = mods[i.row()];
+		m.destroy();
+	}
+	return true;
+}
+
+int ModFolderModel::columnCount(const QModelIndex& parent) const
+{
+	return NUM_COLUMNS;
+}
+
+QVariant ModFolderModel::data(const QModelIndex& index, int role) const
+{
+	if (!index.isValid())
+		return QVariant();
+
+	int row = index.row();
+	int column = index.column();
+
+	if (row < 0 || row >= mods.size())
+		return QVariant();
+
+	switch (role) {
+		case Qt::DisplayRole:
+			switch (column) {
+				case NameColumn:
+					return mods[row].name();
+				case VersionColumn: {
+					switch (mods[row].type()) {
+						case Mod::MOD_FOLDER:
+							return tr("Folder");
+						case Mod::MOD_SINGLEFILE:
+							return tr("File");
+						default:
+							break;
+					}
+					return mods[row].version();
+				}
+				case DateColumn:
+					return mods[row].dateTimeChanged();
+
+				default:
+					return QVariant();
+			}
+
+		case Qt::ToolTipRole:
+			return mods[row].mmc_id();
+
+		case Qt::CheckStateRole:
+			switch (column) {
+				case ActiveColumn:
+					return mods[row].enabled() ? Qt::Checked : Qt::Unchecked;
+				default:
+					return QVariant();
+			}
+		default:
+			return QVariant();
+	}
+}
+
+bool ModFolderModel::setData(const QModelIndex& index, const QVariant& value,
+							 int role)
+{
+	if (index.row() < 0 || index.row() >= rowCount(index) || !index.isValid()) {
+		return false;
+	}
+
+	if (role == Qt::CheckStateRole) {
+		return setModStatus(index.row(), Toggle);
+	}
+	return false;
+}
+
+bool ModFolderModel::setModStatus(int row,
+								  ModFolderModel::ModStatusAction action)
+{
+	if (row < 0 || row >= mods.size()) {
+		return false;
+	}
+
+	auto& mod = mods[row];
+	bool desiredStatus;
+	switch (action) {
+		case Enable:
+			desiredStatus = true;
+			break;
+		case Disable:
+			desiredStatus = false;
+			break;
+		case Toggle:
+		default:
+			desiredStatus = !mod.enabled();
+			break;
+	}
+
+	if (desiredStatus == mod.enabled()) {
+		return true;
+	}
+
+	// preserve the row, but change its ID
+	auto oldId = mod.mmc_id();
+	if (!mod.enable(!mod.enabled())) {
+		return false;
+	}
+	auto newId = mod.mmc_id();
+	if (modsIndex.contains(newId)) {
+		// NOTE: this could handle a corner case, where we are overwriting a
+		// file, because the same 'mod' exists both enabled and disabled But is
+		// it necessary?
+	}
+	modsIndex.remove(oldId);
+	modsIndex[newId] = row;
+	emit dataChanged(index(row, 0), index(row, columnCount(QModelIndex()) - 1));
+	return true;
+}
+
+QVariant ModFolderModel::headerData(int section, Qt::Orientation orientation,
+									int role) const
+{
+	switch (role) {
+		case Qt::DisplayRole:
+			switch (section) {
+				case ActiveColumn:
+					return QString();
+				case NameColumn:
+					return tr("Name");
+				case VersionColumn:
+					return tr("Version");
+				case DateColumn:
+					return tr("Last changed");
+				default:
+					return QVariant();
+			}
+
+		case Qt::ToolTipRole:
+			switch (section) {
+				case ActiveColumn:
+					return tr("Is the mod enabled?");
+				case NameColumn:
+					return tr("The name of the mod.");
+				case VersionColumn:
+					return tr("The version of the mod.");
+				case DateColumn:
+					return tr("The date and time this mod was last changed (or "
+							  "added).");
+				default:
+					return QVariant();
+			}
+		default:
+			return QVariant();
+	}
+	return QVariant();
+}
+
+Qt::ItemFlags ModFolderModel::flags(const QModelIndex& index) const
+{
+	Qt::ItemFlags defaultFlags = QAbstractListModel::flags(index);
+	auto flags = defaultFlags;
+	if (interaction_disabled) {
+		flags &= ~Qt::ItemIsDropEnabled;
+	} else {
+		flags |= Qt::ItemIsDropEnabled;
+		if (index.isValid()) {
+			flags |= Qt::ItemIsUserCheckable;
+		}
+	}
+	return flags;
+}
+
+Qt::DropActions ModFolderModel::supportedDropActions() const
+{
+	// copy from outside, move from within and other mod lists
+	return Qt::CopyAction | Qt::MoveAction;
+}
+
+QStringList ModFolderModel::mimeTypes() const
+{
+	QStringList types;
+	types << "text/uri-list";
+	return types;
+}
+
+bool ModFolderModel::dropMimeData(const QMimeData* data, Qt::DropAction action,
+								  int, int, const QModelIndex&)
+{
+	if (action == Qt::IgnoreAction) {
+		return true;
+	}
+
+	// check if the action is supported
+	if (!data || !(action & supportedDropActions())) {
+		return false;
+	}
+
+	// files dropped from outside?
+	if (data->hasUrls()) {
+		auto urls = data->urls();
+		for (auto url : urls) {
+			// only local files may be dropped...
+			if (!url.isLocalFile()) {
+				continue;
+			}
+			// TODO: implement not only copy, but also move
+			// FIXME: handle errors here
+			installMod(url.toLocalFile());
+		}
+		return true;
+	}
+	return false;
+}