20 files changed, 1672 insertions, 463 deletions

diff --git a/logic/BaseInstaller.cpp b/logic/BaseInstaller.cpp
new file mode 100644
index 00000000..92aa0c92
--- /dev/null
+++ b/logic/BaseInstaller.cpp
@@ -0,0 +1,66 @@
+/* Copyright 2013 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 "BaseInstaller.h"
+
+#include <QFile>
+
+#include "OneSixVersion.h"
+#include "OneSixLibrary.h"
+#include "OneSixInstance.h"
+
+#include "cmdutils.h"
+
+BaseInstaller::BaseInstaller()
+{
+
+}
+
+bool BaseInstaller::isApplied(OneSixInstance *on)
+{
+	return QFile::exists(filename(on->instanceRoot()));
+}
+
+bool BaseInstaller::add(OneSixInstance *to)
+{
+	if (!patchesDir(to->instanceRoot()).exists())
+	{
+		QDir(to->instanceRoot()).mkdir("patches");
+	}
+
+	if (isApplied(to))
+	{
+		if (!remove(to))
+		{
+			return false;
+		}
+	}
+
+	return true;
+}
+
+bool BaseInstaller::remove(OneSixInstance *from)
+{
+	return QFile::remove(filename(from->instanceRoot()));
+}
+
+QString BaseInstaller::filename(const QString &root) const
+{
+	return patchesDir(root).absoluteFilePath(id() + ".json");
+}
+QDir BaseInstaller::patchesDir(const QString &root) const
+{
+	return QDir(root + "/patches/");
+}
diff --git a/logic/BaseInstaller.h b/logic/BaseInstaller.h
new file mode 100644
index 00000000..df7eab89
--- /dev/null
+++ b/logic/BaseInstaller.h
@@ -0,0 +1,39 @@
+/* Copyright 2013 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.
+ */
+
+#pragma once
+
+#include <memory>
+
+class OneSixInstance;
+class QDir;
+class QString;
+
+class BaseInstaller
+{
+public:
+	BaseInstaller();
+
+	virtual bool canApply(OneSixInstance *instance) const { return true; }
+	bool isApplied(OneSixInstance *on);
+
+	virtual bool add(OneSixInstance *to);
+	virtual bool remove(OneSixInstance *from);
+
+protected:
+	virtual QString id() const = 0;
+	QString filename(const QString &root) const;
+	QDir patchesDir(const QString &root) const;
+};
diff --git a/logic/ForgeInstaller.cpp b/logic/ForgeInstaller.cpp
index 8d4c5b41..3e18d17f 100644
--- a/logic/ForgeInstaller.cpp
+++ b/logic/ForgeInstaller.cpp
@@ -21,7 +21,15 @@
 #include <quazipfile.h>
 #include <pathutils.h>
 #include <QStringList>
+#include <QRegularExpression>
+#include <QRegularExpressionMatch>
 #include "MultiMC.h"
+#include "OneSixInstance.h"
+
+#include <QJsonDocument>
+#include <QJsonArray>
+#include <QSaveFile>
+#include <QCryptographicHash>
 
 ForgeInstaller::ForgeInstaller(QString filename, QString universal_url)
 {
@@ -66,6 +74,7 @@ ForgeInstaller::ForgeInstaller(QString filename, QString universal_url)
 	QJsonObject installObj = installVal.toObject();
 	QString libraryName = installObj.value("path").toString();
 	internalPath = installObj.value("filePath").toString();
+	m_forgeVersionString = installObj.value("version").toString().remove("Forge").trimmed();
 
 	// where do we put the library? decode the mojang path
 	OneSixLibrary lib(libraryName);
@@ -103,13 +112,22 @@ ForgeInstaller::ForgeInstaller(QString filename, QString universal_url)
 	realVersionId = m_forge_version->id = installObj.value("minecraft").toString();
 }
 
-bool ForgeInstaller::apply(std::shared_ptr<OneSixVersion> to)
+bool ForgeInstaller::add(OneSixInstance *to)
 {
+	if (!BaseInstaller::add(to))
+	{
+		return false;
+	}
+
+	QJsonObject obj;
+	obj.insert("order", 5);
+
 	if (!m_forge_version)
 		return false;
-	to->externalUpdateStart();
 	int sliding_insert_window = 0;
 	{
+		QJsonArray librariesPlus;
+
 		// for each library in the version we are adding (except for the blacklisted)
 		QSet<QString> blacklist{"lwjgl", "lwjgl_util", "lwjgl-platform"};
 		for (auto lib : m_forge_version->libraries)
@@ -128,28 +146,83 @@ bool ForgeInstaller::apply(std::shared_ptr<OneSixVersion> to)
 			if (blacklist.contains(libName))
 				continue;
 
-			// find an entry that matches this one
+			QJsonObject libObj = lib->toJson();
+
 			bool found = false;
-			for (auto tolib : to->libraries)
+			bool equals = false;
+			// find an entry that matches this one
+			for (auto tolib : to->getVanillaVersion()->libraries)
 			{
 				if (tolib->name() != libName)
 					continue;
 				found = true;
+				if (tolib->toJson() == libObj)
+				{
+					equals = true;
+				}
 				// replace lib
-				tolib = lib;
+				libObj.insert("insert", QString("replace"));
 				break;
 			}
+			if (equals)
+			{
+				continue;
+			}
 			if (!found)
 			{
 				// add lib
-				to->libraries.insert(sliding_insert_window, lib);
+				libObj.insert("insert", QString("prepend"));
+				if (lib->name() == "minecraftforge")
+				{
+					libObj.insert("MMC-depend", QString("hard"));
+				}
 				sliding_insert_window++;
 			}
+			librariesPlus.prepend(libObj);
+		}
+		obj.insert("+libraries", librariesPlus);
+		obj.insert("mainClass", m_forge_version->mainClass);
+		QString args = m_forge_version->minecraftArguments;
+		QStringList tweakers;
+		{
+			QRegularExpression expression("--tweakClass ([a-zA-Z0-9\\.]*)");
+			QRegularExpressionMatch match = expression.match(args);
+			while (match.hasMatch())
+			{
+				tweakers.append(match.captured(1));
+				args.remove(match.capturedStart(), match.capturedLength());
+				match = expression.match(args);
+			}
+		}
+		if (!args.isEmpty() && args != to->getVanillaVersion()->minecraftArguments)
+		{
+			obj.insert("minecraftArguments", args);
+		}
+		if (!tweakers.isEmpty())
+		{
+			obj.insert("+tweakers", QJsonArray::fromStringList(tweakers));
+		}
+		if (!m_forge_version->processArguments.isEmpty() &&
+			m_forge_version->processArguments != to->getVanillaVersion()->processArguments)
+		{
+			obj.insert("processArguments", m_forge_version->processArguments);
 		}
-		to->mainClass = m_forge_version->mainClass;
-		to->minecraftArguments = m_forge_version->minecraftArguments;
-		to->processArguments = m_forge_version->processArguments;
 	}
-	to->externalUpdateFinish();
-	return to->toOriginalFile();
+
+	obj.insert("name", QString("Forge"));
+	obj.insert("fileId", id());
+	obj.insert("version", m_forgeVersionString);
+	obj.insert("mcVersion", to->intendedVersionId());
+
+	QFile file(filename(to->instanceRoot()));
+	if (!file.open(QFile::WriteOnly))
+	{
+		QLOG_ERROR() << "Error opening" << file.fileName()
+					 << "for reading:" << file.errorString();
+		return false;
+	}
+	file.write(QJsonDocument(obj).toJson());
+	file.close();
+
+	return true;
 }
diff --git a/logic/ForgeInstaller.h b/logic/ForgeInstaller.h
index 0b9f9c77..c5052092 100644
--- a/logic/ForgeInstaller.h
+++ b/logic/ForgeInstaller.h
@@ -14,17 +14,22 @@
  */
 
 #pragma once
+
+#include "BaseInstaller.h"
+
 #include <QString>
 #include <memory>
 
 class OneSixVersion;
 
-class ForgeInstaller
+class ForgeInstaller : public BaseInstaller
 {
 public:
 	ForgeInstaller(QString filename, QString universal_url);
 
-	bool apply(std::shared_ptr<OneSixVersion> to);
+	bool add(OneSixInstance *to) override;
+
+	QString id() const override { return "net.minecraftforge"; }
 
 private:
 	// the version, read from the installer
@@ -32,5 +37,6 @@ private:
 	QString internalPath;
 	QString finalPath;
 	QString realVersionId;
+	QString m_forgeVersionString;
 	QString m_universal_url;
 };
diff --git a/logic/InstanceFactory.cpp b/logic/InstanceFactory.cpp
index 1f1a5879..807bccd0 100644
--- a/logic/InstanceFactory.cpp
+++ b/logic/InstanceFactory.cpp
@@ -24,6 +24,7 @@
 #include "OneSixInstance.h"
 #include "OneSixFTBInstance.h"
 #include "NostalgiaInstance.h"
+#include "OneSixInstance.h"
 #include "BaseVersion.h"
 #include "MinecraftVersion.h"
 
@@ -50,13 +51,13 @@ InstanceFactory::InstLoadError InstanceFactory::loadInstance(BaseInstance *&inst
 	QString inst_type = m_settings->get("InstanceType").toString();
 
 	// FIXME: replace with a map lookup, where instance classes register their types
-	if (inst_type == "Legacy")
+	if (inst_type == "OneSix")
 	{
-		inst = new LegacyInstance(instDir, m_settings, this);
+		inst = new OneSixInstance(instDir, m_settings, this);
 	}
-	else if (inst_type == "OneSix")
+	else if (inst_type == "Legacy")
 	{
-		inst = new OneSixInstance(instDir, m_settings, this);
+		inst = new LegacyInstance(instDir, m_settings, this);
 	}
 	else if (inst_type == "Nostalgia")
 	{
@@ -101,6 +102,7 @@ InstanceFactory::InstCreateError InstanceFactory::createInstance(BaseInstance *&
 		switch (mcVer->type)
 		{
 		case MinecraftVersion::Legacy:
+			// TODO new instance type
 			m_settings->set("InstanceType", "Legacy");
 			inst = new LegacyInstance(instDir, m_settings, this);
 			inst->setIntendedVersionId(version->descriptor());
diff --git a/logic/LiteLoaderInstaller.cpp b/logic/LiteLoaderInstaller.cpp
index 07fffff3..c363cad6 100644
--- a/logic/LiteLoaderInstaller.cpp
+++ b/logic/LiteLoaderInstaller.cpp
@@ -15,12 +15,19 @@
 
 #include "LiteLoaderInstaller.h"
 
+#include <QJsonArray>
+#include <QJsonDocument>
+
+#include "logger/QsLog.h"
+
 #include "OneSixVersion.h"
 #include "OneSixLibrary.h"
+#include "OneSixInstance.h"
 
 QMap<QString, QString> LiteLoaderInstaller::m_launcherWrapperVersionMapping;
 
-LiteLoaderInstaller::LiteLoaderInstaller(const QString &mcVersion) : m_mcVersion(mcVersion)
+LiteLoaderInstaller::LiteLoaderInstaller()
+	: BaseInstaller()
 {
 	if (m_launcherWrapperVersionMapping.isEmpty())
 	{
@@ -31,72 +38,60 @@ LiteLoaderInstaller::LiteLoaderInstaller(const QString &mcVersion) : m_mcVersion
 	}
 }
 
-bool LiteLoaderInstaller::canApply() const
+bool LiteLoaderInstaller::canApply(OneSixInstance *instance) const
 {
-	return m_launcherWrapperVersionMapping.contains(m_mcVersion);
+	return m_launcherWrapperVersionMapping.contains(instance->intendedVersionId());
 }
 
-bool LiteLoaderInstaller::apply(std::shared_ptr<OneSixVersion> to)
+bool LiteLoaderInstaller::add(OneSixInstance *to)
 {
-	to->externalUpdateStart();
-
-	applyLaunchwrapper(to);
-	applyLiteLoader(to);
-
-	to->mainClass = "net.minecraft.launchwrapper.Launch";
-	if (!to->minecraftArguments.contains(
-			 " --tweakClass com.mumfrey.liteloader.launch.LiteLoaderTweaker"))
+	if (!BaseInstaller::add(to))
 	{
-		to->minecraftArguments.append(
-			" --tweakClass com.mumfrey.liteloader.launch.LiteLoaderTweaker");
+		return false;
 	}
 
-	to->externalUpdateFinish();
-	return to->toOriginalFile();
-}
+	QJsonObject obj;
 
-void LiteLoaderInstaller::applyLaunchwrapper(std::shared_ptr<OneSixVersion> to)
-{
-	const QString intendedVersion = m_launcherWrapperVersionMapping[m_mcVersion];
+	obj.insert("mainClass", QString("net.minecraft.launchwrapper.Launch"));
+	obj.insert("+tweakers", QJsonArray::fromStringList(QStringList() << "com.mumfrey.liteloader.launch.LiteLoaderTweaker"));
+	obj.insert("order", 10);
 
-	QMutableListIterator<std::shared_ptr<OneSixLibrary>> it(to->libraries);
-	while (it.hasNext())
+	QJsonArray libraries;
+
+	// launchwrapper
 	{
-		it.next();
-		if (it.value()->rawName().startsWith("net.minecraft:launchwrapper:"))
-		{
-			if (it.value()->version() >= intendedVersion)
-			{
-				return;
-			}
-			else
-			{
-				it.remove();
-			}
-		}
+		OneSixLibrary launchwrapperLib("net.minecraft:launchwrapper:" + m_launcherWrapperVersionMapping[to->intendedVersionId()]);
+		launchwrapperLib.finalize();
+		QJsonObject lwLibObj = launchwrapperLib.toJson();
+		lwLibObj.insert("insert", QString("prepend"));
+		libraries.append(lwLibObj);
 	}
 
-	std::shared_ptr<OneSixLibrary> lib(new OneSixLibrary(
-		"net.minecraft:launchwrapper:" + m_launcherWrapperVersionMapping[m_mcVersion]));
-	lib->finalize();
-	to->libraries.prepend(lib);
-}
+	// liteloader
+	{
+		OneSixLibrary liteloaderLib("com.mumfrey:liteloader:" + to->intendedVersionId());
+		liteloaderLib.setBaseUrl("http://dl.liteloader.com/versions/");
+		liteloaderLib.finalize();
+		QJsonObject llLibObj = liteloaderLib.toJson();
+		llLibObj.insert("insert", QString("prepend"));
+		llLibObj.insert("MMC-depend", QString("hard"));
+		libraries.append(llLibObj);
+	}
 
-void LiteLoaderInstaller::applyLiteLoader(std::shared_ptr<OneSixVersion> to)
-{
-	QMutableListIterator<std::shared_ptr<OneSixLibrary>> it(to->libraries);
-	while (it.hasNext())
+	obj.insert("+libraries", libraries);
+	obj.insert("name", QString("LiteLoader"));
+	obj.insert("fileId", id());
+	obj.insert("version", to->intendedVersionId());
+	obj.insert("mcVersion", to->intendedVersionId());
+
+	QFile file(filename(to->instanceRoot()));
+	if (!file.open(QFile::WriteOnly))
 	{
-		it.next();
-		if (it.value()->rawName().startsWith("com.mumfrey:liteloader:"))
-		{
-			it.remove();
-		}
+		QLOG_ERROR() << "Error opening" << file.fileName() << "for reading:" << file.errorString();
+		return false;
 	}
+	file.write(QJsonDocument(obj).toJson());
+	file.close();
 
-	std::shared_ptr<OneSixLibrary> lib(
-		new OneSixLibrary("com.mumfrey:liteloader:" + m_mcVersion));
-	lib->setBaseUrl("http://dl.liteloader.com/versions/");
-	lib->finalize();
-	to->libraries.prepend(lib);
+	return true;
 }
diff --git a/logic/LiteLoaderInstaller.h b/logic/LiteLoaderInstaller.h
index 44b306d6..5e01b16c 100644
--- a/logic/LiteLoaderInstaller.h
+++ b/logic/LiteLoaderInstaller.h
@@ -14,26 +14,22 @@
  */
 
 #pragma once
+
+#include "BaseInstaller.h"
+
 #include <QString>
 #include <QMap>
-#include <memory>
-
-class OneSixVersion;
 
-class LiteLoaderInstaller
+class LiteLoaderInstaller : public BaseInstaller
 {
 public:
-	LiteLoaderInstaller(const QString &mcVersion);
+	LiteLoaderInstaller();
 
-	bool canApply() const;
-
-	bool apply(std::shared_ptr<OneSixVersion> to);
+	bool canApply(OneSixInstance *instance) const override;
+	bool add(OneSixInstance *to) override;
 
 private:
-	QString m_mcVersion;
-
-	void applyLaunchwrapper(std::shared_ptr<OneSixVersion> to);
-	void applyLiteLoader(std::shared_ptr<OneSixVersion> to);
+	virtual QString id() const override { return "com.mumfrey.liteloader"; }
 
 	static QMap<QString, QString> m_launcherWrapperVersionMapping;
 };
diff --git a/logic/OneSixFTBInstance.cpp b/logic/OneSixFTBInstance.cpp
index f8e695b9..ca88142a 100644
--- a/logic/OneSixFTBInstance.cpp
+++ b/logic/OneSixFTBInstance.cpp
@@ -55,15 +55,13 @@ slots:
 		setStatus(tr("Installing Forge..."));
 		QString forgePath = entry->getFullPath();
 		ForgeInstaller forge(forgePath, forgeVersion->universal_url);
-		if (!instance->reloadFullVersion())
+		if (!instance->reloadVersion())
 		{
 			emitFailed(tr("Couldn't load the version config"));
 			return;
 		}
-		instance->revertCustomVersion();
-		instance->customizeVersion();
 		auto version = instance->getFullVersion();
-		if (!forge.apply(version))
+		if (!forge.add(instance))
 		{
 			emitFailed(tr("Couldn't install Forge"));
 			return;
diff --git a/logic/OneSixInstance.cpp b/logic/OneSixInstance.cpp
index 67649f77..ae172f21 100644
--- a/logic/OneSixInstance.cpp
+++ b/logic/OneSixInstance.cpp
@@ -13,32 +13,37 @@
  * limitations under the License.
  */
 
-#include "MultiMC.h"
 #include "OneSixInstance.h"
+
+#include <QIcon>
+
 #include "OneSixInstance_p.h"
 #include "OneSixUpdate.h"
-#include "MinecraftProcess.h"
 #include "OneSixVersion.h"
-#include "JavaChecker.h"
-#include "logic/icons/IconList.h"
-
-#include <setting.h>
-#include <pathutils.h>
-#include <cmdutils.h>
-#include <JlCompress.h>
-#include "gui/dialogs/OneSixModEditDialog.h"
+#include "pathutils.h"
 #include "logger/QsLog.h"
-#include "logic/assets/AssetsUtils.h"
-#include <QIcon>
+#include "assets/AssetsUtils.h"
+#include "MultiMC.h"
+#include "icons/IconList.h"
+#include "MinecraftProcess.h"
+#include "gui/dialogs/OneSixModEditDialog.h"
 
-OneSixInstance::OneSixInstance(const QString &rootDir, SettingsObject *setting_obj,
-							   QObject *parent)
-	: BaseInstance(new OneSixInstancePrivate(), rootDir, setting_obj, parent)
+OneSixInstance::OneSixInstance(const QString &rootDir, SettingsObject *settings, QObject *parent)
+	: BaseInstance(new OneSixInstancePrivate(), rootDir, settings, parent)
 {
 	I_D(OneSixInstance);
 	d->m_settings->registerSetting("IntendedVersion", "");
 	d->m_settings->registerSetting("ShouldUpdate", false);
-	reloadFullVersion();
+	d->version.reset(new OneSixVersion(this, this));
+	d->vanillaVersion.reset(new OneSixVersion(this, this));
+	if (QDir(instanceRoot()).exists("version.json"))
+	{
+		reloadVersion();
+	}
+	else
+	{
+		clearVersion();
+	}
 }
 
 std::shared_ptr<Task> OneSixInstance::doUpdate()
@@ -135,6 +140,10 @@ QStringList OneSixInstance::processMinecraftArgs(AuthSessionPtr session)
 	I_D(OneSixInstance);
 	auto version = d->version;
 	QString args_pattern = version->minecraftArguments;
+	for (auto tweaker : version->tweakers)
+	{
+		args_pattern += " --tweakClass " + tweaker;
+	}
 
 	QMap<QString, QString> token_mapping;
 	// yggdrasil!
@@ -267,11 +276,8 @@ bool OneSixInstance::setIntendedVersionId(QString version)
 {
 	settings().set("IntendedVersion", version);
 	setShouldUpdate(true);
-	auto pathCustom = PathCombine(instanceRoot(), "custom.json");
-	auto pathOrig = PathCombine(instanceRoot(), "version.json");
-	QFile::remove(pathCustom);
-	QFile::remove(pathOrig);
-	reloadFullVersion();
+	QFile::remove(PathCombine(instanceRoot(), "version.json"));
+	clearVersion();
 	return true;
 }
 
@@ -297,9 +303,10 @@ bool OneSixInstance::shouldUpdate() const
 
 bool OneSixInstance::versionIsCustom()
 {
-	QString verpath_custom = PathCombine(instanceRoot(), "custom.json");
-	QFile versionfile(verpath_custom);
-	return versionfile.exists();
+	QDir patches(PathCombine(instanceRoot(), "patches/"));
+	return (patches.exists() && patches.count() >= 0)
+			|| QFile::exists(PathCombine(instanceRoot(), "custom.json"))
+			|| QFile::exists(PathCombine(instanceRoot(), "user.json"));
 }
 
 QString OneSixInstance::currentVersionId() const
@@ -307,62 +314,39 @@ QString OneSixInstance::currentVersionId() const
 	return intendedVersionId();
 }
 
-bool OneSixInstance::customizeVersion()
+bool OneSixInstance::reloadVersion(QWidget *widgetParent)
 {
-	if (!versionIsCustom())
-	{
-		auto pathCustom = PathCombine(instanceRoot(), "custom.json");
-		auto pathOrig = PathCombine(instanceRoot(), "version.json");
-		QFile::copy(pathOrig, pathCustom);
-		return reloadFullVersion();
-	}
-	else
-		return true;
-}
+	I_D(OneSixInstance);
 
-bool OneSixInstance::revertCustomVersion()
-{
-	if (versionIsCustom())
+	bool ret = d->version->reload(widgetParent);
+	if (ret)
 	{
-		auto path = PathCombine(instanceRoot(), "custom.json");
-		QFile::remove(path);
-		return reloadFullVersion();
+		ret = d->vanillaVersion->reload(widgetParent, true);
 	}
-	else
-		return true;
+	emit versionReloaded();
+	return ret;
 }
 
-bool OneSixInstance::reloadFullVersion()
+void OneSixInstance::clearVersion()
 {
 	I_D(OneSixInstance);
-
-	QString verpath = PathCombine(instanceRoot(), "version.json");
-	{
-		QString verpath_custom = PathCombine(instanceRoot(), "custom.json");
-		QFile versionfile(verpath_custom);
-		if (versionfile.exists())
-			verpath = verpath_custom;
-	}
-
-	auto version = OneSixVersion::fromFile(verpath);
-	if (version)
-	{
-		d->version = version;
-		return true;
-	}
-	else
-	{
-		d->version.reset();
-		return false;
-	}
+	d->version->clear();
+	d->vanillaVersion->clear();
+	emit versionReloaded();
 }
 
-std::shared_ptr<OneSixVersion> OneSixInstance::getFullVersion()
+std::shared_ptr<OneSixVersion> OneSixInstance::getFullVersion() const
 {
-	I_D(OneSixInstance);
+	I_D(const OneSixInstance);
 	return d->version;
 }
 
+std::shared_ptr<OneSixVersion> OneSixInstance::getVanillaVersion() const
+{
+	I_D(const OneSixInstance);
+	return d->vanillaVersion;
+}
+
 QString OneSixInstance::defaultBaseJar() const
 {
 	return "versions/" + intendedVersionId() + "/" + intendedVersionId() + ".jar";
@@ -382,7 +366,7 @@ bool OneSixInstance::menuActionEnabled(QString action_name) const
 
 QString OneSixInstance::getStatusbarDescription()
 {
-	QString descr = "One Six : " + intendedVersionId();
+	QString descr = "OneSix : " + intendedVersionId();
 	if (versionIsCustom())
 	{
 		descr + " (custom)";
diff --git a/logic/OneSixInstance.h b/logic/OneSixInstance.h
index c159723b..ae95eab1 100644
--- a/logic/OneSixInstance.h
+++ b/logic/OneSixInstance.h
@@ -15,21 +15,17 @@
 
 #pragma once
 
-#include <QStringList>
-#include <QDir>
-
 #include "BaseInstance.h"
 
-class OneSixVersion;
-class Task;
-class ModList;
+#include "OneSixVersion.h"
+#include "ModList.h"
 
 class OneSixInstance : public BaseInstance
 {
 	Q_OBJECT
 public:
 	explicit OneSixInstance(const QString &rootDir, SettingsObject *settings,
-							QObject *parent = 0);
+						  QObject *parent = 0);
 
 	//////  Mod Lists  //////
 	std::shared_ptr<ModList> loaderModList();
@@ -55,14 +51,14 @@ public:
 
 	virtual QDialog *createModEditDialog(QWidget *parent) override;
 
-	/// reload the full version json file. return true on success!
-	bool reloadFullVersion();
+	/// reload the full version json files. return true on success!
+	bool reloadVersion(QWidget *widgetParent = 0);
+	/// clears all version information in preparation for an update
+	void clearVersion();
 	/// get the current full version info
-	std::shared_ptr<OneSixVersion> getFullVersion();
-	/// revert the current custom version back to base
-	bool revertCustomVersion();
-	/// customize the current base version
-	bool customizeVersion();
+	std::shared_ptr<OneSixVersion> getFullVersion() const;
+	/// gets the current version info, but only for version.json
+	std::shared_ptr<OneSixVersion> getVanillaVersion() const;
 	/// is the current version original, or custom?
 	virtual bool versionIsCustom() override;
 
@@ -72,6 +68,9 @@ public:
 	virtual bool menuActionEnabled(QString action_name) const override;
 	virtual QString getStatusbarDescription() override;
 
+signals:
+	void versionReloaded();
+
 private:
 	QStringList processMinecraftArgs(AuthSessionPtr account);
 	QDir reconstructAssets(std::shared_ptr<OneSixVersion> version);
diff --git a/logic/OneSixInstance_p.h b/logic/OneSixInstance_p.h
index 6b7ea431..0cc46f33 100644
--- a/logic/OneSixInstance_p.h
+++ b/logic/OneSixInstance_p.h
@@ -15,16 +15,14 @@
 
 #pragma once
 
-#include <memory>
-
-#include "logic/BaseInstance_p.h"
-#include "logic/OneSixVersion.h"
-#include "logic/OneSixLibrary.h"
-#include "logic/ModList.h"
+#include "BaseInstance_p.h"
+#include "OneSixVersion.h"
+#include "ModList.h"
 
 struct OneSixInstancePrivate : public BaseInstancePrivate
 {
 	std::shared_ptr<OneSixVersion> version;
+	std::shared_ptr<OneSixVersion> vanillaVersion;
 	std::shared_ptr<ModList> loader_mod_list;
 	std::shared_ptr<ModList> resource_pack_list;
-};
\ No newline at end of file
+};
diff --git a/logic/OneSixLibrary.cpp b/logic/OneSixLibrary.cpp
index 7b80d5e7..c78679d1 100644
--- a/logic/OneSixLibrary.cpp
+++ b/logic/OneSixLibrary.cpp
@@ -46,7 +46,7 @@ void OneSixLibrary::finalize()
 	}
 
 	m_decentname = parts[1];
-	m_decentversion = parts[2];
+	m_decentversion = minVersion = parts[2];
 	m_storage_path = relative;
 	m_download_url = m_base_url + relative;
 
@@ -76,11 +76,11 @@ void OneSixLibrary::finalize()
 	}
 }
 
-void OneSixLibrary::setName(QString name)
+void OneSixLibrary::setName(const QString &name)
 {
 	m_name = name;
 }
-void OneSixLibrary::setBaseUrl(QString base_url)
+void OneSixLibrary::setBaseUrl(const QString &base_url)
 {
 	m_base_url = base_url;
 }
@@ -88,50 +88,54 @@ void OneSixLibrary::setIsNative()
 {
 	m_is_native = true;
 }
-void OneSixLibrary::addNative(OpSys os, QString suffix)
+void OneSixLibrary::addNative(OpSys os, const QString &suffix)
 {
 	m_is_native = true;
 	m_native_suffixes[os] = suffix;
 }
+void OneSixLibrary::clearSuffixes()
+{
+	m_native_suffixes.clear();
+}
 void OneSixLibrary::setRules(QList<std::shared_ptr<Rule>> rules)
 {
 	m_rules = rules;
 }
-bool OneSixLibrary::isActive()
+bool OneSixLibrary::isActive() const
 {
 	return m_is_active;
 }
-bool OneSixLibrary::isNative()
+bool OneSixLibrary::isNative() const
 {
 	return m_is_native;
 }
-QString OneSixLibrary::downloadUrl()
+QString OneSixLibrary::downloadUrl() const
 {
 	if (m_absolute_url.size())
 		return m_absolute_url;
 	return m_download_url;
 }
-QString OneSixLibrary::storagePath()
+QString OneSixLibrary::storagePath() const
 {
 	return m_storage_path;
 }
 
-void OneSixLibrary::setAbsoluteUrl(QString absolute_url)
+void OneSixLibrary::setAbsoluteUrl(const QString &absolute_url)
 {
 	m_absolute_url = absolute_url;
 }
 
-QString OneSixLibrary::absoluteUrl()
+QString OneSixLibrary::absoluteUrl() const
 {
 	return m_absolute_url;
 }
 
-void OneSixLibrary::setHint(QString hint)
+void OneSixLibrary::setHint(const QString &hint)
 {
 	m_hint = hint;
 }
 
-QString OneSixLibrary::hint()
+QString OneSixLibrary::hint() const
 {
 	return m_hint;
 }
@@ -176,7 +180,7 @@ bool OneSixLibrary::extractTo(QString target_dir)
 		cooked_storage.replace("${arch}", "32");
 		QString origin = PathCombine("libraries", cooked_storage);
 		QString target_dir_cooked = PathCombine(target_dir, "32");
-		if(!ensureFolderPathExists(target_dir_cooked))
+		if (!ensureFolderPathExists(target_dir_cooked))
 		{
 			QLOG_ERROR() << "Couldn't create folder " + target_dir_cooked;
 			return false;
@@ -191,7 +195,7 @@ bool OneSixLibrary::extractTo(QString target_dir)
 		cooked_storage.replace("${arch}", "64");
 		origin = PathCombine("libraries", cooked_storage);
 		target_dir_cooked = PathCombine(target_dir, "64");
-		if(!ensureFolderPathExists(target_dir_cooked))
+		if (!ensureFolderPathExists(target_dir_cooked))
 		{
 			QLOG_ERROR() << "Couldn't create folder " + target_dir_cooked;
 			return false;
@@ -205,7 +209,7 @@ bool OneSixLibrary::extractTo(QString target_dir)
 	}
 	else
 	{
-		if(!ensureFolderPathExists(target_dir))
+		if (!ensureFolderPathExists(target_dir))
 		{
 			QLOG_ERROR() << "Couldn't create folder " + target_dir;
 			return false;
@@ -230,8 +234,10 @@ QJsonObject OneSixLibrary::toJson()
 		libRoot.insert("MMC-hint", m_hint);
 	if (m_base_url != "http://" + URLConstants::AWS_DOWNLOAD_LIBRARIES &&
 		m_base_url != "https://" + URLConstants::AWS_DOWNLOAD_LIBRARIES &&
-		m_base_url != "https://" + URLConstants::LIBRARY_BASE)
+		m_base_url != "https://" + URLConstants::LIBRARY_BASE && !m_base_url.isEmpty())
+	{
 		libRoot.insert("url", m_base_url);
+	}
 	if (isNative() && m_native_suffixes.size())
 	{
 		QJsonObject nativeList;
diff --git a/logic/OneSixLibrary.h b/logic/OneSixLibrary.h
index 227cdbef..371ca6f4 100644
--- a/logic/OneSixLibrary.h
+++ b/logic/OneSixLibrary.h
@@ -60,12 +60,21 @@ private:
 
 public: