1 files changed, 103 insertions, 0 deletions
diff --git a/meshmc/launcher/minecraft/launch/ModMinecraftJar.cpp b/meshmc/launcher/minecraft/launch/ModMinecraftJar.cpp
new file mode 100644
index 0000000000..72da25ec64
--- /dev/null
+++ b/meshmc/launcher/minecraft/launch/ModMinecraftJar.cpp
@@ -0,0 +1,103 @@
+/* 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 "ModMinecraftJar.h"
+#include "launch/LaunchTask.h"
+#include "MMCZip.h"
+#include "minecraft/OpSys.h"
+#include "FileSystem.h"
+#include "minecraft/MinecraftInstance.h"
+#include "minecraft/PackProfile.h"
+
+void ModMinecraftJar::executeTask()
+{
+	auto m_inst =
+		std::dynamic_pointer_cast<MinecraftInstance>(m_parent->instance());
+
+	if (!m_inst->getJarMods().size()) {
+		emitSucceeded();
+		return;
+	}
+	// nuke obsolete stripped jar(s) if needed
+	if (!FS::ensureFolderPathExists(m_inst->binRoot())) {
+		emitFailed(tr("Couldn't create the bin folder for Minecraft.jar"));
+	}
+
+	auto finalJarPath =
+		QDir(m_inst->binRoot()).absoluteFilePath("minecraft.jar");
+	if (!removeJar()) {
+		emitFailed(tr("Couldn't remove stale jar file: %1").arg(finalJarPath));
+	}
+
+	// create temporary modded jar, if needed
+	auto components = m_inst->getPackProfile();
+	auto profile = components->getProfile();
+	auto jarMods = m_inst->getJarMods();
+	if (jarMods.size()) {
+		auto mainJar = profile->getMainJar();
+		QStringList jars, temp1, temp2, temp3, temp4;
+		mainJar->getApplicableFiles(currentSystem, jars, temp1, temp2, temp3,
+									m_inst->getLocalLibraryPath());
+		auto sourceJarPath = jars[0];
+		if (!MMCZip::createModdedJar(sourceJarPath, finalJarPath, jarMods)) {
+			emitFailed(tr("Failed to create the custom Minecraft jar file."));
+			return;
+		}
+	}
+	emitSucceeded();
+}
+
+void ModMinecraftJar::finalize()
+{
+	removeJar();
+}
+
+bool ModMinecraftJar::removeJar()
+{
+	auto m_inst =
+		std::dynamic_pointer_cast<MinecraftInstance>(m_parent->instance());
+	auto finalJarPath =
+		QDir(m_inst->binRoot()).absoluteFilePath("minecraft.jar");
+	QFile finalJar(finalJarPath);
+	if (finalJar.exists()) {
+		if (!finalJar.remove()) {
+			return false;
+		}
+	}
+	return true;
+}