Massive renaming in the backend folder, all around restructure in the same.

38 files changed, 4624 insertions, 0 deletions

diff --git a/backend/BaseInstance.cpp b/backend/BaseInstance.cpp
new file mode 100644
index 00000000..c2ffa664
--- /dev/null
+++ b/backend/BaseInstance.cpp
@@ -0,0 +1,199 @@
+/* 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 "BaseInstance.h"
+
+#include <QFileInfo>
+
+#include "inisettingsobject.h"
+#include "setting.h"
+#include "overridesetting.h"
+
+#include "pathutils.h"
+#include <lists/MinecraftVersionList.h>
+
+BaseInstance::BaseInstance(const QString &rootDir, QObject *parent) :
+	QObject(parent)
+{
+	m_rootDir = rootDir;
+	m_settings = new INISettingsObject(PathCombine(rootDir, "instance.cfg"), this);
+	
+	settings().registerSetting(new Setting("name", "Unnamed Instance"));
+	settings().registerSetting(new Setting("iconKey", "default"));
+	settings().registerSetting(new Setting("notes", ""));
+	settings().registerSetting(new Setting("NeedsRebuild", true));
+	settings().registerSetting(new Setting("ShouldUpdate", false));
+	settings().registerSetting(new Setting("JarVersion", "Unknown"));
+	settings().registerSetting(new Setting("LwjglVersion", "2.9.0"));
+	settings().registerSetting(new Setting("IntendedJarVersion", ""));
+	settings().registerSetting(new Setting("lastLaunchTime", 0));
+	
+	// Java Settings
+	settings().registerSetting(new OverrideSetting("JavaPath", globalSettings->getSetting("JavaPath")));
+	settings().registerSetting(new OverrideSetting("JvmArgs", globalSettings->getSetting("JvmArgs")));
+	
+	// Custom Commands
+	settings().registerSetting(new OverrideSetting("PreLaunchCommand", 
+												   globalSettings->getSetting("PreLaunchCommand")));
+	settings().registerSetting(new OverrideSetting("PostExitCommand", 
+												   globalSettings->getSetting("PostExitCommand")));
+	
+	// Window Size
+	settings().registerSetting(new OverrideSetting("LaunchCompatMode", globalSettings->getSetting("LaunchCompatMode")));
+	settings().registerSetting(new OverrideSetting("LaunchMaximized", globalSettings->getSetting("LaunchMaximized")));
+	settings().registerSetting(new OverrideSetting("MinecraftWinWidth", globalSettings->getSetting("MinecraftWinWidth")));
+	settings().registerSetting(new OverrideSetting("MinecraftWinHeight", globalSettings->getSetting("MinecraftWinHeight")));
+	
+	// Memory
+	settings().registerSetting(new OverrideSetting("MinMemAlloc", globalSettings->getSetting("MinMemAlloc")));
+	settings().registerSetting(new OverrideSetting("MaxMemAlloc", globalSettings->getSetting("MaxMemAlloc")));
+	
+	// Auto login
+	settings().registerSetting(new OverrideSetting("AutoLogin", globalSettings->getSetting("AutoLogin")));
+	
+	// Console
+	settings().registerSetting(new OverrideSetting("ShowConsole", globalSettings->getSetting("ShowConsole")));
+	settings().registerSetting(new OverrideSetting("AutoCloseConsole", globalSettings->getSetting("AutoCloseConsole")));
+	
+	// Overrides
+	settings().registerSetting(new Setting("OverrideConsole", false));
+	settings().registerSetting(new Setting("OverrideWindow", false));
+	settings().registerSetting(new Setting("OverrideLogin", false));
+	settings().registerSetting(new Setting("OverrideMemory", false));
+	settings().registerSetting(new Setting("OverrideJava", false));
+	settings().registerSetting(new Setting("OverrideCommands", false));
+}
+
+QString BaseInstance::id() const
+{
+	return QFileInfo(rootDir()).fileName();
+}
+
+QString BaseInstance::rootDir() const
+{
+	return m_rootDir;
+}
+
+InstanceList *BaseInstance::instList() const
+{
+	if (parent()->inherits("InstanceList"))
+		return (InstanceList *)parent();
+	else
+		return NULL;
+}
+
+QString BaseInstance::minecraftDir() const
+{
+	QFileInfo mcDir(PathCombine(rootDir(), "minecraft"));
+	QFileInfo dotMCDir(PathCombine(rootDir(), ".minecraft"));
+	
+	if (dotMCDir.exists() && !mcDir.exists())
+        return dotMCDir.filePath();
+	else
+		return mcDir.filePath();
+}
+
+QString BaseInstance::instModsDir() const
+{
+	return PathCombine(rootDir(), "instMods");
+}
+
+QString BaseInstance::binDir() const
+{
+	return PathCombine(minecraftDir(), "bin");
+}
+
+QString BaseInstance::savesDir() const
+{
+	return PathCombine(minecraftDir(), "saves");
+}
+
+QString BaseInstance::mlModsDir() const
+{
+	return PathCombine(minecraftDir(), "mods");
+}
+
+QString BaseInstance::coreModsDir() const
+{
+	return PathCombine(minecraftDir(), "coremods");
+}
+
+QString BaseInstance::resourceDir() const
+{
+	return PathCombine(minecraftDir(), "resources");
+}
+
+QString BaseInstance::screenshotsDir() const
+{
+	return PathCombine(minecraftDir(), "screenshots");
+}
+
+QString BaseInstance::texturePacksDir() const
+{
+	return PathCombine(minecraftDir(), "texturepacks");
+}
+
+QString BaseInstance::mcJar() const
+{
+	return PathCombine(binDir(), "minecraft.jar");
+}
+
+QString BaseInstance::mcBackup() const
+{
+	return PathCombine(binDir(), "mcbackup.jar");
+}
+
+QString BaseInstance::modListFile() const
+{
+	return PathCombine(rootDir(), "modlist");
+}
+
+InstVersionList *BaseInstance::versionList() const
+{
+	return &MinecraftVersionList::getMainList();
+}
+
+bool BaseInstance::shouldUpdateCurrentVersion() const
+{
+	QFileInfo jar(mcJar());
+	return jar.lastModified().toUTC().toMSecsSinceEpoch() != lastCurrentVersionUpdate();
+}
+
+void BaseInstance::updateCurrentVersion(bool keepCurrent)
+{
+	QFileInfo jar(mcJar());
+	
+	if(!jar.exists())
+	{
+		setLastCurrentVersionUpdate(0);
+		setCurrentVersion("Unknown");
+		return;
+	}
+	
+	qint64 time = jar.lastModified().toUTC().toMSecsSinceEpoch();
+	
+	setLastCurrentVersionUpdate(time);
+	if (!keepCurrent)
+	{
+		// TODO: Implement GetMinecraftJarVersion function.
+		QString newVersion = "Unknown";//javautils::GetMinecraftJarVersion(jar.absoluteFilePath());
+		setCurrentVersion(newVersion);
+	}
+}
+
+SettingsObject &BaseInstance::settings() const
+{
+	return *m_settings;
+}
diff --git a/backend/BaseInstance.h b/backend/BaseInstance.h
new file mode 100644
index 00000000..51f55b5e
--- /dev/null
+++ b/backend/BaseInstance.h
@@ -0,0 +1,313 @@
+/* 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 <QObject>
+#include <QDateTime>
+
+#include <settingsobject.h>
+
+#include "inifile.h"
+#include "lists/InstVersionList.h"
+
+#include "libmmc_config.h"
+
+class InstanceList;
+
+/*!
+ * \brief Base class for instances.
+ * This class implements many functions that are common between instances and 
+ * provides a standard interface for all instances.
+ * 
+ * To create a new instance type, create a new class inheriting from this class
+ * and implement the pure virtual functions.
+ */
+class LIBMULTIMC_EXPORT BaseInstance : public QObject
+{
+	Q_OBJECT
+	
+	// Properties
+	/*!
+	 * The instance's ID.
+	 * This is a unique identifier string that is, by default, set to the 
+	 * instance's folder name. It's not always the instance's folder name, 
+	 * however, as any class deriving from Instance can override the id() 
+	 * method and change how the ID is determined. The instance's ID should 
+	 * always remain constant. Undefined behavior results if an already loaded 
+	 * instance's ID changes.
+	 */
+	Q_PROPERTY(QString id READ id STORED false)
+	
+	//! Path to the instance's root directory.
+	Q_PROPERTY(QString rootDir READ rootDir)
+	
+	//! The name of the instance that is displayed to the user.
+	Q_PROPERTY(QString name READ name WRITE setName)
+	
+	//! The instance's icon key.
+	Q_PROPERTY(QString iconKey READ iconKey WRITE setIconKey)
+	
+	//! The instance's notes.
+	Q_PROPERTY(QString notes READ notes WRITE setNotes)
+	
+	//! The instance's group.
+	Q_PROPERTY(QString group READ group WRITE setGroup)
+	
+	/*!
+	 * Gets the time that the instance was last launched.
+	 * Stored in milliseconds since epoch.
+	 * This value is usually used for things like sorting instances by the time
+	 * they were last launched.
+	 */
+	Q_PROPERTY(qint64 lastLaunch READ lastLaunch WRITE setLastLaunch)
+	
+	/*!
+	 * Whether or not the instance's minecraft.jar needs to be rebuilt.
+	 * If this is true, when the instance launches, its jar mods will be 
+	 * re-added to a fresh minecraft.jar file.
+	 */
+	Q_PROPERTY(bool shouldRebuild READ shouldRebuild WRITE setShouldRebuild)
+	
+	/*!
+	 * Whether or not Minecraft should be downloaded when the instance is launched.
+	 * This returns true if shouldForceUpdate game is true or if the intended and 
+	 * current versions don't match.
+	 */
+	Q_PROPERTY(bool shouldUpdate READ shouldUpdate WRITE setShouldUpdate)
+	
+	/*!
+	 * The instance's current version.
+	 * This value represents the instance's current version. If this value is 
+	 * different from the intendedVersion, the instance should be updated.
+	 * \warning Don't change this value unless you know what you're doing.
+	 */
+	Q_PROPERTY(QString currentVersion READ currentVersion WRITE setCurrentVersion)
+	
+	/*!
+	 * The version that the user has set for this instance to use.
+	 * If this is not the same as currentVersion, the instance's game updater
+	 * will be run on launch.
+	 */
+	Q_PROPERTY(QString intendedVersion READ intendedVersion WRITE setIntendedVersion)
+	
+	//! The version of LWJGL that this instance uses.
+	Q_PROPERTY(QString lwjglVersion READ lwjglVersion WRITE setLWJGLVersion)
+	
+	
+	/*!
+	 * Gets the last time that the current version was checked.
+	 * This is checked against the last modified time on the jar file to see if
+	 * the current version needs to be checked again.
+	 */
+	Q_PROPERTY(qint64 lastCurrentVersionUpdate READ lastCurrentVersionUpdate WRITE setLastCurrentVersionUpdate)
+	
+	// Dirs
+	//! Path to the instance's .minecraft folder.
+	Q_PROPERTY(QString minecraftDir READ minecraftDir STORED false)
+	
+	//! Path to the instance's instMods folder.
+	Q_PROPERTY(QString instModsDir READ instModsDir STORED false)
+	
+	//! Path to the instance's bin folder.
+	Q_PROPERTY(QString binDir READ binDir STORED false)
+	
+	//! Path to the instance's saves folder.
+	Q_PROPERTY(QString savesDir READ savesDir STORED false)
+	
+	//! Path to the instance's mods folder (.minecraft/mods)
+	Q_PROPERTY(QString mlModsDir READ mlModsDir STORED false)
+	
+	//! Path to the instance's coremods folder.
+	Q_PROPERTY(QString coreModsDir READ coreModsDir STORED false)
+	
+	//! Path to the instance's resources folder.
+	Q_PROPERTY(QString resourceDir READ resourceDir STORED false)
+	
+	//! Path to the instance's screenshots folder.
+	Q_PROPERTY(QString screenshotsDir READ screenshotsDir STORED false)
+	
+	//! Path to the instance's texturepacks folder.
+	Q_PROPERTY(QString texturePacksDir READ texturePacksDir STORED false)
+	
+	
+	// Files
+	//! Path to the instance's minecraft.jar
+	Q_PROPERTY(QString mcJar READ mcJar STORED false)
+	
+	//! Path to the instance's mcbackup.jar
+	Q_PROPERTY(QString mcBackup READ mcBackup STORED false)
+	
+	//! Path to the instance's modlist file.
+	Q_PROPERTY(QString modListFile READ modListFile STORED false)
+	
+public:
+	explicit BaseInstance(const QString &rootDir, QObject *parent = 0);
+	
+	//////// STUFF ////////
+	virtual QString id() const;
+	
+	virtual QString rootDir() const;
+	
+	/*!
+	 * \brief Gets the instance list that this instance is a part of. 
+	 *        Returns NULL if this instance is not in a list 
+	 *        (the parent is not an InstanceList).
+	 * \return A pointer to the InstanceList containing this instance. 
+	 */
+	virtual InstanceList *instList() const;
+	
+	
+	//////// INSTANCE INFO ////////
+	
+	//// General Info ////
+	virtual QString name() const { return settings().get("name").toString(); }
+	virtual void setName(QString val)
+	{
+		settings().set("name", val);
+		emit propertiesChanged(this);
+	}
+	
+	virtual QString iconKey() const { return settings().get("iconKey").toString(); }
+	virtual void setIconKey(QString val)
+	{
+		settings().set("iconKey", val);
+		emit propertiesChanged(this);
+	}
+	
+	virtual QString notes() const { return settings().get("notes").toString(); }
+	virtual void setNotes(QString val) { settings().set("notes", val); }
+	
+	virtual QString group() const { return m_group; }
+	virtual void setGroup(QString val)
+	{
+		m_group = val;
+		emit propertiesChanged(this);
+	}
+	
+	virtual bool shouldRebuild() const { return settings().get("NeedsRebuild").toBool(); }
+	virtual void setShouldRebuild(bool val) { settings().set("NeedsRebuild", val); }
+	
+	
+	//// Version Stuff ////
+	
+	virtual QString currentVersion() const { return settings().get("JarVersion").toString(); }
+	virtual void setCurrentVersion(QString val) { settings().set("JarVersion", val); }
+	
+	virtual QString lwjglVersion() const { return settings().get("LwjglVersion").toString(); }
+	virtual void setLWJGLVersion(QString val) { settings().set("LwjglVersion", val); }
+	
+	virtual QString intendedVersion() const { return settings().get("IntendedJarVersion").toString(); }
+	virtual void setIntendedVersion(QString val) { settings().set("IntendedJarVersion", val); }
+	
+	virtual bool shouldUpdate() const 
+	{
+		QVariant var = settings().get("ShouldUpdate");
+		if(!var.isValid() || var.toBool() == false)
+		{
+			return intendedVersion() != currentVersion();
+		}
+		return true;
+	}
+	virtual void setShouldUpdate(bool val) { settings().set("ShouldUpdate", val); }
+
+	//// Timestamps ////
+	
+	virtual qint64 lastLaunch() const { return settings().get("lastLaunchTime").value<qint64>(); }
+	virtual void setLastLaunch(qint64 val = QDateTime::currentMSecsSinceEpoch()) 
+	{
+		settings().set("lastLaunchTime", val);
+		emit propertiesChanged(this);
+	}
+	
+	virtual qint64 lastCurrentVersionUpdate() const { return settings().get("lastVersionUpdate").value<qint64>(); }
+	virtual void setLastCurrentVersionUpdate(qint64 val) { settings().set("lastVersionUpdate", val); }
+	
+	////// Directories //////
+	QString minecraftDir() const;
+	QString instModsDir() const;
+	QString binDir() const;
+	QString savesDir() const;
+	QString mlModsDir() const;
+	QString coreModsDir() const;
+	QString resourceDir() const;
+	QString screenshotsDir() const;
+	QString texturePacksDir() const;
+	
+	
+	////// Files //////
+	QString mcJar() const;
+	QString mcBackup() const;
+	QString modListFile() const;
+	
+	
+	//////// LISTS, LISTS, AND MORE LISTS ////////
+	/*!
+	 * \brief Gets a pointer to this instance's version list.
+	 * \return A pointer to the available version list for this instance.
+	 */
+	virtual InstVersionList *versionList() const;
+	
+	
+	//////// OTHER FUNCTIONS ////////
+	
+	//// Version System ////
+	
+	/*!
+	 * \brief Checks whether or not the currentVersion of the instance needs to be updated. 
+	 *        If this returns true, updateCurrentVersion is called. In the 
+	 *        standard instance, this is determined by checking a timestamp 
+	 *        stored in the instance config file against the last modified time of Minecraft.jar.
+	 * \return True if updateCurrentVersion() should be called.
+	 */
+	virtual bool shouldUpdateCurrentVersion() const;
+	
+	/*!
+	 * \brief Updates the current version. 
+	 *        This function should first set the current version timestamp 
+	 *        (setCurrentVersionTimestamp()) to the current time. Next, if 
+	 *        keepCurrent is false, this function should check what the 
+	 *        instance's current version is and call setCurrentVersion() to 
+	 *        update it. This function will automatically be called when the 
+	 *        instance is loaded if shouldUpdateCurrentVersion returns true.
+	 * \param keepCurrent If true, only the version timestamp will be updated.
+	 */
+	virtual void updateCurrentVersion(bool keepCurrent = false); 
+	
+	
+	//// Settings System ////
+	
+	/*!
+	 * \brief Gets this instance's settings object.
+	 * This settings object stores instance-specific settings.
+	 * \return A pointer to this instance's settings object.
+	 */
+	virtual SettingsObject &settings() const;
+	
+signals:
+	/*!
+	 * \brief Signal emitted when properties relevant to the instance view change
+	 */
+	void propertiesChanged(BaseInstance * inst);
+	
+private:
+	QString m_rootDir;
+	QString m_group;
+	SettingsObject *m_settings;
+};
+
+// pointer for lazy people
+typedef QSharedPointer<BaseInstance> InstancePtr;
+
diff --git a/backend/CMakeLists.txt b/backend/CMakeLists.txt
new file mode 100644
index 00000000..a17b7dfe
--- /dev/null
+++ b/backend/CMakeLists.txt
@@ -0,0 +1,91 @@
+project(libMultiMC)
+
+set(CMAKE_AUTOMOC ON)
+
+# Find Qt
+find_package(Qt5Core REQUIRED)
+find_package(Qt5Network REQUIRED)
+find_package(Qt5Xml REQUIRED)
+
+# Include Qt headers.
+include_directories(${Qt5Base_INCLUDE_DIRS})
+include_directories(${Qt5Network_INCLUDE_DIRS})
+
+# Include utility library.
+include_directories(${CMAKE_SOURCE_DIR}/libutil/include)
+
+# Include settings library.
+include_directories(${CMAKE_SOURCE_DIR}/libsettings/include)
+
+SET(LIBINST_HEADERS
+libmmc_config.h
+
+# Instance Stuff
+BaseInstance.h
+LegacyInstance.h
+OneSixInstance.h
+InstanceFactory.h
+
+# Versions
+InstanceVersion.h
+MinecraftVersion.h
+OneSixVersion.h
+VersionFactory.h
+
+# Lists
+lists/InstanceList.h
+lists/InstVersionList.h
+lists/MinecraftVersionList.h
+lists/LwjglVersionList.h
+
+# Tasks
+tasks/Task.h
+tasks/LoginTask.h
+tasks/LoginResponse.h
+tasks/UserInfo.h
+tasks/GameUpdateTask.h
+
+MinecraftProcess.h
+)
+
+SET(LIBINST_SOURCES
+# Instance Stuff
+BaseInstance.cpp
+LegacyInstance.cpp
+OneSixInstance.cpp
+InstanceFactory.cpp
+
+# Versions
+InstanceVersion.cpp
+MinecraftVersion.cpp
+OneSixVersion.cpp
+VersionFactory.cpp
+
+# Lists
+lists/InstanceList.cpp
+lists/InstVersionList.cpp
+lists/MinecraftVersionList.cpp
+lists/LwjglVersionList.cpp
+
+# Tasks
+tasks/Task.cpp
+tasks/LoginTask.cpp
+tasks/GameUpdateTask.cpp
+tasks/UserInfo.cpp
+tasks/LoginResponse.cpp
+
+MinecraftProcess.cpp
+)
+
+# Set the include dir path.
+SET(LIBMULTIMC_INCLUDE_DIR "${CMAKE_CURRENT_SOURCE_DIR}" PARENT_SCOPE)
+
+# Include self.
+include_directories(${CMAKE_CURRENT_SOURCE_DIR})
+include_directories(${CMAKE_BINARY_DIR}/include)
+
+add_definitions(-DLIBMULTIMC_LIBRARY)
+
+add_library(backend SHARED ${LIBINST_SOURCES} ${LIBINST_HEADERS})
+qt5_use_modules(backend Core Network Xml)
+target_link_libraries(backend libUtil libSettings)
diff --git a/backend/InstanceFactory.cpp b/backend/InstanceFactory.cpp
new file mode 100644
index 00000000..318650ae
--- /dev/null
+++ b/backend/InstanceFactory.cpp
@@ -0,0 +1,61 @@
+/* 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 "InstanceFactory.h"
+
+#include <QDir>
+#include <QFileInfo>
+
+#include "BaseInstance.h"
+
+#include "inifile.h"
+
+#include "pathutils.h"
+
+InstanceFactory InstanceFactory::loader;
+
+InstanceFactory::InstanceFactory() :
+	QObject(NULL)
+{
+	
+}
+
+InstanceFactory::InstLoadError InstanceFactory::loadInstance(BaseInstance *&inst, const QString &instDir)
+{
+	BaseInstance *loadedInst = new BaseInstance(instDir, this);
+	
+	// TODO: Sanity checks to verify that the instance is valid.
+	
+	inst = loadedInst;
+	
+	return NoLoadError;
+}
+
+
+InstanceFactory::InstCreateError InstanceFactory::createInstance(BaseInstance *&inst, const QString &instDir)
+{
+	QDir rootDir(instDir);
+	
+	qDebug(instDir.toUtf8());
+	if (!rootDir.exists() && !rootDir.mkpath("."))
+	{
+		return InstanceFactory::CantCreateDir;
+	}
+	
+	inst = new BaseInstance(instDir, this);
+	
+	//FIXME: really, how do you even know?
+	return InstanceFactory::NoCreateError;
+}
diff --git a/backend/InstanceFactory.h b/backend/InstanceFactory.h
new file mode 100644
index 00000000..0dd4c5d8
--- /dev/null
+++ b/backend/InstanceFactory.h
@@ -0,0 +1,79 @@
+/* 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 <QObject>
+#include <QMap>
+#include <QList>
+
+#include "libmmc_config.h"
+
+class BaseInstance;
+
+/*!
+ * The \bInstanceFactory\b is a singleton that manages loading and creating instances.
+ */
+class LIBMULTIMC_EXPORT InstanceFactory : public QObject
+{
+	Q_OBJECT
+public:
+	/*!
+	 * \brief Gets a reference to the instance loader.
+	 */
+	static InstanceFactory &get() { return loader; }
+	
+	enum InstLoadError
+	{
+		NoLoadError = 0,
+		UnknownLoadError,
+		NotAnInstance
+	};
+	
+	enum InstCreateError
+	{
+		NoCreateError = 0,
+		UnknownCreateError,
+		InstExists,
+		CantCreateDir
+	};
+	
+	/*!
+	 * \brief Creates an instance with the given type and stores it in inst.
+	 *
+	 * \param inst Pointer to store the created instance in.
+	 * \param type The type of instance to create.
+	 * \param instDir The instance's directory.
+	 * \return An InstCreateError error code.
+	 * - InstExists if the given instance directory is already an instance.
+	 * - CantCreateDir if the given instance directory cannot be created.
+	 */
+	InstCreateError createInstance(BaseInstance *&inst, const QString &instDir);
+	
+	/*!
+	 * \brief Loads an instance from the given directory.
+	 * Checks the instance's INI file to figure out what the instance's type is first.
+	 * \param inst Pointer to store the loaded instance in.
+	 * \param instDir The instance's directory.
+	 * \return An InstLoadError error code.
+	 * - NotAnInstance if the given instance directory isn't a valid instance.
+	 */
+	InstLoadError loadInstance(BaseInstance *&inst, const QString &instDir);
+	
+private:
+	InstanceFactory();
+	
+	static InstanceFactory loader;
+};
diff --git a/backend/InstanceVersion.cpp b/backend/InstanceVersion.cpp
new file mode 100644
index 00000000..1b9b0a5b
--- /dev/null
+++ b/backend/InstanceVersion.cpp
@@ -0,0 +1,67 @@
+/* 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 "InstanceVersion.h"
+#include "lists/InstVersionList.h"
+
+InstVersion::InstVersion(const QString &descriptor, 
+						 const QString &name, 
+						 qint64 timestamp, 
+						 InstVersionList *parent) :
+	QObject(parent), m_descriptor(descriptor), m_name(name), m_timestamp(timestamp)
+{
+	
+}
+
+InstVersion::InstVersion(const InstVersion &other, QObject *parent) :
+	QObject(parent ? parent : other.parent()), 
+	m_descriptor(other.descriptor()), m_name(other.name()), m_timestamp(other.timestamp())
+{
+	
+}
+
+InstVersionList *InstVersion::versionList() const
+{
+	// Parent should *always* be either an InstVersionList or NULL.
+	if (!parent() || !parent()->inherits("InstVersionList"))
+		return NULL;
+	else
+		return (InstVersionList *)parent();
+}
+
+bool InstVersion::isLessThan(const InstVersion &other) const
+{
+	return timestamp() < other.timestamp();
+}
+
+bool InstVersion::isGreaterThan(const InstVersion &other) const
+{
+	return timestamp() > other.timestamp();
+}
+
+QString InstVersion::descriptor() const
+{
+	return m_descriptor;
+}
+
+QString InstVersion::name() const
+{
+	return m_name;
+}
+
+qint64 InstVersion::timestamp() const
+{
+	return m_timestamp;
+}
diff --git a/backend/InstanceVersion.h b/backend/InstanceVersion.h
new file mode 100644
index 00000000..5ebae41e
--- /dev/null
+++ b/backend/InstanceVersion.h
@@ -0,0 +1,121 @@
+/* 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 <QObject>
+
+#include "libmmc_config.h"
+
+class InstVersionList;
+
+/*!
+ * An abstract base class for instance versions.
+ * InstVersions hold information about versions such as their names, identifiers,
+ * types, etc.
+ */
+class LIBMULTIMC_EXPORT InstVersion : public QObject
+{
+	Q_OBJECT
+	
+	/*!
+	 * A string used to identify this version in config files.
+	 * This should be unique within the version list or shenanigans will occur.
+	 */
+	Q_PROPERTY(QString descriptor READ descriptor CONSTANT)
+	
+	/*!
+	 * The name of this version as it is displayed to the user.
+	 * For example: "1.5.1"
+	 */
+	Q_PROPERTY(QString name READ name)
+	
+	/*!
+	 * The name of this version's type as it is displayed to the user.
+	 * For example: "Latest Version", "Snapshot", or "MCNostalgia"
+	 */
+	Q_PROPERTY(QString typeName READ typeName)
+	
+	/*!
+	 * Gets the version's timestamp.
+	 * This is primarily used for sorting versions in a list.
+	 */
+	Q_PROPERTY(qint64 timestamp READ timestamp)
+	
+	
+public:
+	/*!
+	 * \brief Constructs a new InstVersion with the given parent. 
+	 * The parent *must* be the InstVersionList that contains this InstVersion. 
+	 * The InstVersion will be added to the list immediately after being created.
+	 */
+	explicit InstVersion(const QString &descriptor, 
+						 const QString &name,
+						 qint64 timestamp,
+						 InstVersionList *parent = 0);
+	
+	/*!
+	 * Copy constructor.
+	 * If the 'parent' parameter is not NULL, sets this version's parent to the
+	 * specified object, rather than setting it to the same parent as the version
+	 * we're copying from.
+	 * \param other The version to copy.
+	 * \param parent If not NULL, will be set as the new version object's parent.
+	 */
+	InstVersion(const InstVersion &other, QObject *parent = 0);
+	
+	virtual QString descriptor() const;
+	virtual QString name() const;
+	virtual QString typeName() const = 0;
+	virtual qint64 timestamp() const;
+	
+	virtual InstVersionList *versionList() const;
+	
+	/*!
+	 * Creates a copy of this version with a different parent.
+	 * \param newParent The parent QObject of the copy.
+	 * \return A new, identical copy of this version with the given parent set.
+	 */
+	virtual InstVersion *copyVersion(InstVersionList *newParent) const = 0;
+	
+	/*!
+	 * Checks if this version is less (older) than the given version.
+	 * \param other The version to compare this one to.
+	 * \return True if this version is older than the given version.
+	 */
+	virtual bool isLessThan(const InstVersion &other) const;
+	
+	/*!
+	 * Checks if this version is greater (newer) than the given version.
+	 * \param other The version to compare this one to.
+	 * \return True if this version is newer than the given version.
+	 */
+	virtual bool isGreaterThan(const InstVersion &other) const;
+	
+	/*!
+	 * \sa shouldSortBefore()
+	 */
+	virtual bool operator<(const InstVersion &rhs) { return isLessThan(rhs); }
+	
+	/*!
+	 * \sa shouldSortAfter()
+	 */
+	virtual bool operator>(const InstVersion &rhs) { return isGreaterThan(rhs); }
+	
+protected:
+	QString m_descriptor;
+	QString m_name;
+	qint64 m_timestamp;
+};
diff --git a/backend/LegacyInstance.cpp b/backend/LegacyInstance.cpp
new file mode 100644
index 00000000..e69de29b
--- /dev/null
+++ b/backend/LegacyInstance.cpp
diff --git a/backend/LegacyInstance.h b/backend/LegacyInstance.h
new file mode 100644
index 00000000..7b9637ef
--- /dev/null
+++ b/backend/LegacyInstance.h
@@ -0,0 +1 @@
+#pragma once
\ No newline at end of file
diff --git a/backend/MinecraftProcess.cpp b/backend/MinecraftProcess.cpp
new file mode 100644
index 00000000..e53feb5b
--- /dev/null
+++ b/backend/MinecraftProcess.cpp
@@ -0,0 +1,229 @@
+/* Copyright 2013 MultiMC Contributors
+ *
+ * Authors: Orochimarufan <orochimarufan.x3@gmail.com>
+ *
+ * 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 "MinecraftProcess.h"
+
+#include <QDataStream>
+#include <QFile>
+#include <QDir>
+//#include <QImage>
+#include <QProcessEnvironment>
+
+#include "BaseInstance.h"
+
+#include "osutils.h"
+#include "pathutils.h"
+#include "cmdutils.h"
+
+#define LAUNCHER_FILE "MultiMCLauncher.jar"
+#define IBUS "@im=ibus"
+
+// prepare tools
+inline void MinecraftProcess::extractIcon(BaseInstance *inst, QString destination)
+{
+//	QImage(":/icons/instances/" + inst->iconKey()).save(destination);
+}
+
+inline void MinecraftProcess::extractLauncher(QString destination)
+{
+	QFile(":/launcher/launcher.jar").copy(destination);
+}
+
+void MinecraftProcess::prepare(BaseInstance *inst)
+{
+	extractLauncher(PathCombine(inst->minecraftDir(), LAUNCHER_FILE));
+	extractIcon(inst, PathCombine(inst->minecraftDir(), "icon.png"));
+}
+
+// constructor
+MinecraftProcess::MinecraftProcess(BaseInstance *inst, QString user, QString session) :
+	m_instance(inst), m_user(user), m_session(session)
+{
+	connect(this, SIGNAL(finished(int, QProcess::ExitStatus)), SLOT(finish(int, QProcess::ExitStatus)));
+	
+	// prepare the process environment
+	QProcessEnvironment env = QProcessEnvironment::systemEnvironment();
+	
+#ifdef LINUX
+	// Strip IBus
+	if (env.value("XMODIFIERS").contains(IBUS))
+		env.insert("XMODIFIERS", env.value("XMODIFIERS").replace(IBUS, ""));
+#endif
+	
+	// export some infos
+	env.insert("INST_NAME", inst->name());
+	env.insert("INST_ID", inst->id());
+	env.insert("INST_DIR", QDir(inst->rootDir()).absolutePath());
+	
+	this->setProcessEnvironment(env);
+	m_prepostlaunchprocess.setProcessEnvironment(env);
+	
+	// set the cwd
+	QDir mcDir(inst->minecraftDir());
+	this->setWorkingDirectory(mcDir.absolutePath());
+	m_prepostlaunchprocess.setWorkingDirectory(mcDir.absolutePath());
+	
+	// std channels
+	connect(this, SIGNAL(readyReadStandardError()), SLOT(on_stdErr()));
+	connect(this, SIGNAL(readyReadStandardOutput()), SLOT(on_stdOut()));
+}
+
+// console window
+void MinecraftProcess::on_stdErr()
+{
+	QByteArray data = readAllStandardError();
+	QString str = m_err_leftover + QString::fromLocal8Bit(data);
+	m_err_leftover.clear();
+	QStringList lines = str.split("\n");
+	bool complete = str.endsWith("\n");
+	
+	for(int i = 0; i < lines.size() - 1; i++)
+	{
+		QString & line = lines[i];
+		MessageLevel::Enum level = MessageLevel::Error;
+		if(line.contains("[INFO]") || line.contains("[CONFIG]") || line.contains("[FINE]") || line.contains("[FINER]") || line.contains("[FINEST]") )
+			level = MessageLevel::Message;
+		if(line.contains("[SEVERE]") || line.contains("[WARNING]") || line.contains("[STDERR]"))
+			level = MessageLevel::Error;
+		emit log(lines[i].toLocal8Bit(), level);
+	}
+	if(!complete)
+		m_err_leftover = lines.last();
+}
+
+void MinecraftProcess::on_stdOut()
+{
+	QByteArray data = readAllStandardOutput();
+	QString str = m_out_leftover + QString::fromLocal8Bit(data);
+	m_out_leftover.clear();
+	QStringList lines = str.split("\n");
+	bool complete = str.endsWith("\n");
+	
+	for(int i = 0; i < lines.size() - 1; i++)
+	{
+		QString & line = lines[i];
+		emit log(lines[i].toLocal8Bit(), MessageLevel::Message);
+	}
+	if(!complete)
+		m_out_leftover = lines.last();
+}
+
+// exit handler
+void MinecraftProcess::finish(int code, ExitStatus status)
+{
+	if (status != NormalExit)
+	{
+		//TODO: error handling
+	}
+	
+	emit log("Minecraft exited.");
+	
+	m_prepostlaunchprocess.processEnvironment().insert("INST_EXITCODE", QString(code));
+	
+	// run post-exit
+	if (!m_instance->settings().get("PostExitCommand").toString().isEmpty())
+	{
+		m_prepostlaunchprocess.start(m_instance->settings().get("PostExitCommand").toString());
+		m_prepostlaunchprocess.waitForFinished();
+		if (m_prepostlaunchprocess.exitStatus() != NormalExit)
+		{
+			//TODO: error handling
+		}
+	}
+	
+//	if (m_console != nullptr)
+//		m_console->setMayClose(true);
+	
+	emit ended();
+}
+
+void MinecraftProcess::launch()
+{
+	if (!m_instance->settings().get("PreLaunchCommand").toString().isEmpty())
+	{
+		m_prepostlaunchprocess.start(m_instance->settings().get("PreLaunchCommand").toString());
+		m_prepostlaunchprocess.waitForFinished();
+		if (m_prepostlaunchprocess.exitStatus() != NormalExit)
+		{
+			//TODO: error handling
+			return;
+		}
+	}
+	
+	m_instance->setLastLaunch();
+	
+	prepare(m_instance);
+	
+	genArgs();
+	
+	emit log(QString("Minecraft folder is: '%1'").arg(workingDirectory()));
+	QString JavaPath = m_instance->settings().get("JavaPath").toString();
+	emit log(QString("Java path: '%1'").arg(JavaPath));
+	emit log(QString("Arguments: '%1'").arg(m_arguments.join("' '")));
+	start(JavaPath, m_arguments);
+	if (!waitForStarted())
+	{
+		emit log("Could not launch minecraft!");
+		return;
+		//TODO: error handling
+	}
+	
+//	if(m_console != nullptr)
+//		m_console->setMayClose(false);
+}
+
+void MinecraftProcess::genArgs()
+{
+	// start fresh
+	m_arguments.clear();
+	
+	// window size
+	QString windowSize;
+	if (m_instance->settings().get("LaunchMaximized").toBool())
+		windowSize = "max";
+	else
+		windowSize = QString("%1x%2").
+				arg(m_instance->settings().get("MinecraftWinWidth").toInt()).
+				arg(m_instance->settings().get("MinecraftWinHeight").toInt());
+	
+	// window title
+	QString windowTitle;
+	windowTitle.append("MultiMC: ").append(m_instance->name());
+	
+	// Java arguments
+	m_arguments.append(Util::Commandline::splitArgs(m_instance->settings().get("JvmArgs").toString()));
+	
+#ifdef OSX
+	// OSX dock icon and name
+	m_arguments << "-Xdock:icon=icon.png";
+	m_arguments << QString("-Xdock:name=\"%1\"").arg(windowTitle);
+#endif
+	
+	// lwjgl
+	QString lwjgl = QDir(globalSettings->get("LWJGLDir").toString() + "/" + 
+						 m_instance->lwjglVersion()).absolutePath();
+	
+	// launcher arguments
+	m_arguments << QString("-Xms%1m").arg(m_instance->settings().get("MinMemAlloc").toInt());
+	m_arguments << QString("-Xmx%1m").arg(m_instance->settings().get("MaxMemAlloc").toInt());
+	m_arguments << "-jar" << LAUNCHER_FILE;
+	m_arguments << m_user;
+	m_arguments << m_session;
+	m_arguments << windowTitle;
+	m_arguments << windowSize;
+	m_arguments << lwjgl;
+}
diff --git a/backend/MinecraftProcess.h b/backend/MinecraftProcess.h
new file mode 100644
index 00000000..c846f5f4
--- /dev/null
+++ b/backend/MinecraftProcess.h
@@ -0,0 +1,111 @@
+/* Copyright 2013 MultiMC Contributors
+ *
+ * Authors: Orochimarufan <orochimarufan.x3@gmail.com>
+ *
+ * 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 <QProcess>
+
+#include "BaseInstance.h"
+
+#include "libmmc_config.h"
+
+/**
+ * @brief the MessageLevel Enum
+ * defines what level a message is
+ */
+namespace MessageLevel {
+enum LIBMULTIMC_EXPORT Enum {
+	MultiMC,	/**< MultiMC Messages */
+	Debug,		/**< Debug Messages */
+	Info,		/**< Info Messages */
+	Message,	/**< Standard Messages */
+	Warning,	/**< Warnings */
+	Error,		/**< Errors */
+	Fatal		/**< Fatal Errors */
+};
+}
+
+/**
+ * @file data/minecraftprocess.h
+ * @brief The MinecraftProcess class
+ */
+class LIBMULTIMC_EXPORT MinecraftProcess : public QProcess
+{
+	Q_OBJECT
+public:
+	/**
+	 * @brief MinecraftProcess constructor
+	 * @param inst the Instance pointer to launch
+	 * @param user the minecraft username
+	 * @param session the minecraft session id
+	 * @param console the instance console window
+	 */
+	MinecraftProcess(BaseInstance *inst, QString user, QString session);
+
+	/**
+	 * @brief launch minecraft
+	 */
+	void launch();
+
+	/**
+	 * @brief extract the instance icon
+	 * @param inst the instance
+	 * @param destination the destination path
+	 */
+	static inline void extractIcon(BaseInstance *inst, QString destination);
+
+	/**
+	 * @brief extract the MultiMC launcher.jar
+	 * @param destination the destination path
+	 */
+	static inline void extractLauncher(QString destination);
+
+	/**
+	 * @brief prepare the launch by extracting icon and launcher
+	 * @param inst the instance
+	 */
+	static void prepare(BaseInstance *inst);
+
+signals:
+	/**
+	 * @brief emitted when mc has finished and the PostLaunchCommand was run
+	 */
+	void ended();
+
+	/**
+	 * @brief emitted when we want to log something
+	 * @param text the text to log
+	 * @param level the level to log at
+	 */
+	void log(QString text, MessageLevel::Enum level=MessageLevel::MultiMC);
+
+protected:
+	BaseInstance *m_instance;
+	QString m_user;
+	QString m_session;
+	QString m_err_leftover;
+	QString m_out_leftover;
+	QProcess m_prepostlaunchprocess;
+	QStringList m_arguments;
+
+	void genArgs();
+
+protected slots:
+	void finish(int, QProcess::ExitStatus status);
+	void on_stdErr();
+	void on_stdOut();
+
+};
diff --git a/backend/MinecraftVersion.cpp b/backend/MinecraftVersion.cpp
new file mode 100644
index 00000000..6f3b1b86
--- /dev/null
+++ b/backend/MinecraftVersion.cpp
@@ -0,0 +1,104 @@
+/* Copyright 2013 Andrew Okin
+ *
+ * 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 "MinecraftVersion.h"
+
+MinecraftVersion::MinecraftVersion(QString descriptor, 
+								   QString name, 
+								   qint64 timestamp, 
+								   QString dlUrl, 
+								   QString etag, 
+								   InstVersionList *parent) :
+		InstVersion(descriptor, name, timestamp, parent), m_dlUrl(dlUrl), m_etag(etag)
+{
+}
+
+QString MinecraftVersion::descriptor() const
+{
+	return m_descriptor;
+}
+
+QString MinecraftVersion::name() const
+{
+	return m_name;
+}
+
+QString MinecraftVersion::typeName() const
+{
+	switch (versionType())
+	{
+	case OldSnapshot:
+		return "Snapshot";
+		
+	case Stable:
+		return "Stable";
+		
+	case CurrentStable:
+		return "Current Stable";
+		
+	case Snapshot:
+		return "Snapshot";
+		
+	case MCNostalgia:
+		return "MCNostalgia";
+		
+	default:
+		return QString("Unknown Type %1").arg(versionType());
+	}
+}
+
+qint64 MinecraftVersion::timestamp() const
+{
+	return m_timestamp;
+}
+
+MinecraftVersion::VersionType MinecraftVersion::versionType() const
+{
+	return m_type;
+}
+
+void MinecraftVersion::setVersionType(MinecraftVersion::VersionType typeName)
+{
+	m_type = typeName;
+}
+
+QString MinecraftVersion::downloadURL() const
+{
+	return m_dlUrl;
+}
+
+QString MinecraftVersion::etag() const
+{
+	return m_etag;
+}
+
+MinecraftVersion::VersionSource MinecraftVersion::versionSource() const
+{
+	return m_versionSource;
+};
+
+void MinecraftVersion::setVersionSource(VersionSource launcherVersion)
+{
+	m_versionSource = launcherVersion;
+}
+
+InstVersion *MinecraftVersion::copyVersion(InstVersionList *newParent) const
+{
+	MinecraftVersion *version = new MinecraftVersion(
+				descriptor(), name(), timestamp(), downloadURL(), etag(), newParent);
+	version->setVersionType(versionType());
+	version->setVersionSource(VersionSource());
+	return version;
+}
diff --git a/backend/MinecraftVersion.h b/backend/MinecraftVersion.h
new file mode 100644
index 00000000..a69b4710
--- /dev/null
+++ b/backend/MinecraftVersion.h
@@ -0,0 +1,80 @@
+/* Copyright 2013 Andrew Okin
+ *
+ * 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 "libmmc_config.h"
+
+#include "InstanceVersion.h"
+
+class LIBMULTIMC_EXPORT MinecraftVersion : public InstVersion
+{
+	Q_OBJECT
+	
+public:
+	explicit MinecraftVersion(QString descriptor, 
+							  QString name, 
+							  qint64 timestamp, 
+							  QString dlUrl, 
+							  QString etag, 
+							  InstVersionList *parent = 0);
+	
+	static InstVersion *mcnVersion(QString rawName, QString niceName);
+	
+	enum VersionType
+	{
+		OldSnapshot,
+		Stable,
+		CurrentStable,
+		Snapshot,
+		MCNostalgia
+	};
+	
+	enum VersionSource
+	{
+		Unknown = -1,
+		Legacy = 0, // the legacy launcher that's been around since ... forever
+		Launcher16 = 1, // current launcher as of 26/06/2013
+	};
+	
+	virtual QString descriptor() const;
+	virtual QString name() const;
+	virtual QString typeName() const;
+	virtual qint64 timestamp() const;
+	
+	virtual VersionType versionType() const;
+	virtual void setVersionType(VersionType typeName);
+	
+	virtual VersionSource versionSource() const;
+	virtual void setVersionSource(VersionSource launcherVersion);
+	
+	virtual QString downloadURL() const;
+	virtual QString etag() const;
+	
+	virtual InstVersion *copyVersion(InstVersionList *newParent) const;
+	
+private:
+	/// The URL that this version will be downloaded from. maybe.
+	QString m_dlUrl;
+	
+	/// ETag/MD5 Used to verify the integrity of the downloaded minecraft.jar.
+	QString m_etag;
+	
+	/// This version's type. Used internally to identify what kind of version this is.
+	VersionType m_type;
+	
+	/// Whete to get the full version info (or, where did we get this version from originally)
+	VersionSource m_versionSource;
+};
diff --git a/backend/OneSixInstance.cpp b/backend/OneSixInstance.cpp
new file mode 100644
index 00000000..e69de29b
--- /dev/null
+++ b/backend/OneSixInstance.cpp
diff --git a/backend/OneSixInstance.h b/backend/OneSixInstance.h
new file mode 100644
index 00000000..7b9637ef
--- /dev/null
+++ b/backend/OneSixInstance.h
@@ -0,0 +1 @@
+#pragma once
\ No newline at end of file
diff --git a/backend/OneSixVersion.cpp b/backend/OneSixVersion.cpp
new file mode 100644
index 00000000..b58870ce
--- /dev/null
+++ b/backend/OneSixVersion.cpp
@@ -0,0 +1,91 @@
+#include "OneSixVersion.h"
+
+RuleAction RuleAction_fromString(QString name)
+{
+	if(name == "allow")
+		return Allow;
+	if(name == "disallow")
+		return Disallow;
+	return Defer;
+}
+
+OpSys OpSys_fromString(QString name)
+{
+	if(name == "linux")
+		return Os_Linux;
+	if(name == "windows")
+		return Os_Windows;
+	if(name == "osx")
+		return Os_OSX;
+	return Os_Other;
+}
+
+void Library::finalize()
+{
+	QStringList parts = m_name.split ( ':' );
+	QString relative = parts[0];
+	relative.replace ( '.','/' );
+	relative += '/' + parts[1] + '/' + parts[2] + '/' + parts[1] + '-' + parts[2];
+	if ( !m_is_native )
+		relative += ".jar";
+	else
+	{
+		if ( m_native_suffixes.contains ( currentSystem ) )
+		{
+			relative += "-" + m_native_suffixes[currentSystem] + ".jar";
+		}
+		else
+		{
+			// really, bad.
+			relative += ".jar";
+		}
+	}
+	m_storage_path = relative;
+	m_download_path = m_base_url + relative;
+
+	if ( m_rules.empty() )
+	{
+		m_is_active = true;
+	}
+	else
+	{
+		RuleAction result = Disallow;
+		for ( auto rule: m_rules )
+		{
+			RuleAction temp = rule->apply ( this );
+			if ( temp != Defer )
+				result = temp;
+		}
+		m_is_active = ( result == Allow );
+	}
+	if ( m_is_native )
+	{
+		m_is_active = m_is_active && m_native_suffixes.contains ( currentSystem );
+	}
+}
+
+QList<QSharedPointer<Library> > FullVersion::getActiveNormalLibs()
+{
+	QList<QSharedPointer<Library> > output;
+	for ( auto lib: libraries )
+	{
+		if (lib->getIsActive() && !lib->getIsNative())
+		{
+			output.append(lib);
+		}
+	}
+	return output;
+}
+
+QList<QSharedPointer<Library> > FullVersion::getActiveNativeLibs()
+{
+	QList<QSharedPointer<Library> > output;
+	for ( auto lib: libraries )
+	{
+		if (lib->getIsActive() && lib->getIsNative())
+		{
+			output.append(lib);
+		}
+	}
+	return output;
+}
diff --git a/backend/OneSixVersion.h b/backend/OneSixVersion.h
new file mode 100644
index 00000000..762e8f3e
--- /dev/null
+++ b/backend/OneSixVersion.h
@@ -0,0 +1,265 @@
+#pragma once
+#include <QtCore>
+
+class Library;
+
+enum OpSys
+{
+	Os_Windows,
+	Os_Linux,
+	Os_OSX,
+	Os_Other
+};
+
+OpSys OpSys_fromString(QString);
+
+#ifdef Q_OS_MAC
+	#define currentSystem Os_OSX
+#endif
+
+#ifdef Q_OS_LINUX
+	#define currentSystem Os_Linux
+#endif
+
+#ifdef Q_OS_WIN32
+	#define currentSystem Os_Windows
+#endif
+
+#ifndef currentSystem
+	#define currentSystem Os_Other
+#endif
+
+
+enum RuleAction
+{
+	Allow,
+	Disallow,
+	Defer
+};
+
+RuleAction RuleAction_fromString(QString);
+
+class Rule
+{
+protected:
+	RuleAction m_result;
+	virtual bool applies(Library * parent) = 0;
+public:
+	Rule(RuleAction result)
+		:m_result(result) {}
+	virtual ~Rule(){};
+	RuleAction apply(Library * parent)
+	{
+		if(applies(parent))
+			return m_result;
+		else
+			return Defer;
+	};
+};
+
+class OsRule : public Rule
+{
+private:
+	// the OS
+	OpSys m_system;
+	// the OS version regexp
+	QString m_version_regexp;
+protected:
+	virtual bool applies ( Library* )
+	{
+		return (m_system == currentSystem);
+	}
+	OsRule(RuleAction result, OpSys system, QString version_regexp)
+		: Rule(result), m_system(system), m_version_regexp(version_regexp) {}
+public:
+	static QSharedPointer<OsRule> create(RuleAction result, OpSys system, QString version_regexp)
+	{
+		return QSharedPointer<OsRule> (new OsRule(result, system, version_regexp));
+	}
+};
+
+class ImplicitRule : public Rule
+{
+protected:
+	virtual bool applies ( Library* )
+	{
+		return true;
+	}
+	ImplicitRule(RuleAction result)
+		: Rule(result) {}
+public:
+	static QSharedPointer<ImplicitRule> create(RuleAction result)
+	{
+		return QSharedPointer<ImplicitRule> (new ImplicitRule(result));
+	}
+};
+
+class Library
+{
+private:
+	// basic values used internally (so far)
+	QString m_name;
+	QString m_base_url;
+	QList<QSharedPointer<Rule> > m_rules;
+	
+	// derived values used for real things
+	/// where to store the lib locally
+	QString m_storage_path;
+	/// where to download the lib from
+	QString m_download_path;
+	/// is this lib actuall active on the current OS?
+	bool m_is_active;
+	
+	// native lib?
+	bool m_is_native;
+	QMap<OpSys, QString> m_native_suffixes;
+public:
+	QStringList extract_excludes;
+	
+public:
+	/// Constructor
+	Library(QString name)
+	{
+		m_is_native = false;
+		m_is_native = false;
+		m_name = name;
+		m_base_url = "https://s3.amazonaws.com/Minecraft.Download/libraries/";
+	}
+	
+	/**
+	 * finalize the library, processing the input values into derived values and state
+	 * 
+	 * This SHALL be called after all the values are parsed or after any further change.
+	 */
+	void finalize();
+	
+	
+	/**
+	 * Set the library composite name
+	 */
+	void setName(QString name)
+	{
+		m_name = name;
+	}
+	
+	/**
+	 * Set the url base for downloads
+	 */
+	void setBaseUrl(QString base_url)
+	{
+		m_base_url = base_url;
+	}
+	
+	/**
+	 * Call this to mark the library as 'native' (it's a zip archive with DLLs)
+	 */
+	void setIsNative()
+	{
+		m_is_native = true;
+	}
+	
+	/**
+	 * Attach a name suffix to the specified OS native
+	 */
+	void addNative(OpSys os, QString suffix)
+	{
+		m_is_native = true;
+		m_native_suffixes[os] = suffix;
+	}
+	
+	/**
+	 * Set the load rules
+	 */
+	void setRules(QList<QSharedPointer<Rule> > rules)
+	{
+		m_rules = rules;
+	}
+
+	/**
+	 * Returns true if the library should be loaded (or extracted, in case of natives)
+	 */
+	bool getIsActive()
+	{
+		return m_is_active;
+	}
+	/**
+	 * Returns true if the library is native
+	 */
+	bool getIsNative()
+	{
+		return m_is_native;
+	}
+};
+
+
+class FullVersion
+{
+public:
+	/// the ID - determines which jar to use! ACTUALLY IMPORTANT!
+	QString id;
+	/// Last updated time - as a string
+	QString time;
+	/// Release time - as a string
+	QString releaseTime;
+	/// Release type - "release" or "snapshot"
+	QString type;
+	/**
+	 * DEPRECATED: Old versions of the new vanilla launcher used this
+	 * ex: "username_session_version"
+	 */
+	QString processArguments; 
+	/**
+	 * arguments that should be used for launching minecraft
+	 * 
+	 * ex: "--username ${auth_player_name} --session ${auth_session}
+	 *      --version ${version_name} --gameDir ${game_directory} --assetsDir ${game_assets}"
+	 */
+	QString minecraftArguments;
+	/**
+	 * the minimum launcher version required by this version ... current is 4 (at point of writing)
+	 */
+	int minimumLauncherVersion;
+	/**
+	 * The main class to load first
+	 */
+	QString mainClass;
+	
+	/// the list of libs - both active and inactive, native and java
+	QList<QSharedPointer<Library> > libraries;
+	
+	/**
+	 * is this actually a legacy version? if so, none of the other stuff here will be ever used.
+	 * added by FullVersionFactory
+	 */
+	bool isLegacy;
+
+	/*
+	FIXME: add support for those rules here? Looks like a pile of quick hacks to me though.
+
+	"rules": [
+		{
+		"action": "allow"
+		},
+		{
+		"action": "disallow",
+		"os": {
+			"name": "osx",
+			"version": "^10\\.5\\.\\d$"
+		}
+		}
+	],
+	"incompatibilityReason": "There is a bug in LWJGL which makes it incompatible with OSX 10.5.8. Please go to New Profile and use 1.5.2 for now. Sorry!"
+	}
+	*/
+	// QList<Rule> rules;
+	
+public:
+	FullVersion()
+	{
+		minimumLauncherVersion = 0xDEADBEEF;
+		isLegacy = false;
+	}
+	
+	QList<QSharedPointer<Library> > getActiveNormalLibs();
+	QList<QSharedPointer<Library> > getActiveNativeLibs();
+};
\ No newline at end of file
diff --git a/backend/VersionFactory.cpp b/backend/VersionFactory.cpp
new file mode 100644
index 00000000..d0242f17
--- /dev/null
+++ b/backend/VersionFactory.cpp
@@ -0,0 +1,194 @@
+#include "VersionFactory.h"
+#include "OneSixVersion.h"
+
+// Library rules (if any)
+QList<QSharedPointer<Rule> > FullVersionFactory::parse4rules(QJsonObject & baseObj)
+{
+	QList<QSharedPointer<Rule> > rules;
+	auto rulesVal = baseObj.value("rules");
+	if(rulesVal.isArray())
+	{
+		QJsonArray ruleList = rulesVal.toArray();
+		for(auto ruleVal : ruleList)
+		{
+			QSharedPointer<Rule> rule;
+			if(!ruleVal.isObject())
+				continue;
+			auto ruleObj = ruleVal.toObject();
+			auto actionVal = ruleObj.value("action");
+			if(!actionVal.isString())
+				continue;
+			auto action = RuleAction_fromString(actionVal.toString());
+			if(action == Defer)
+				continue;
+			
+			auto osVal = ruleObj.value("os");
+			if(!osVal.isObject())
+			{
+				// add a new implicit action rule
+				rules.append(ImplicitRule::create(action));
+			}
+			else
+			{
+				auto osObj = osVal.toObject();
+				auto osNameVal = osObj.value("name");
+				if(!osNameVal.isString())
+					continue;
+				OpSys requiredOs = OpSys_fromString(osNameVal.toString());
+				QString versionRegex = osObj.value("version").toString();
+				// add a new OS rule
+				rules.append(OsRule::create(action, requiredOs, versionRegex));
+			}
+		}
+	}
+	return rules;
+}
+
+
+QSharedPointer<FullVersion> FullVersionFactory::parse4(QJsonObject root, QSharedPointer<FullVersion> fullVersion)
+{
+	fullVersion->id = root.value("id").toString();
+	
+	// if it's on our legacy list, it's legacy
+	if(legacyWhitelist.contains(fullVersion->id))
+		fullVersion->isLegacy = true;
+	
+	fullVersion->mainClass = root.value("mainClass").toString();
+	auto procArgsValue = root.value("processArguments");
+	if(procArgsValue.isString())
+	{
+		fullVersion->processArguments = procArgsValue.toString();
+		QString toCompare = fullVersion->processArguments.toLower();
+		if(toCompare == "legacy")
+		{
+			fullVersion->minecraftArguments = " ${auth_player_name} ${auth_session}";
+			fullVersion->isLegacy = true;
+		}
+		else if(toCompare == "username_session")
+		{
+			fullVersion->minecraftArguments = "--username ${auth_player_name} --session ${auth_session}";
+		}
+		else if(toCompare == "username_session_version")
+		{
+			fullVersion->minecraftArguments = "--username ${auth_player_name} --session ${auth_session} --version ${profile_name}";
+		}
+	}
+	
+	auto minecraftArgsValue = root.value("minecraftArguments");
+	if(minecraftArgsValue.isString())
+	{
+		fullVersion->minecraftArguments = minecraftArgsValue.toString();
+	}
+	
+	fullVersion->releaseTime = root.value("releaseTime").toString();
+	fullVersion->time = root.value("time").toString();
+	
+	// Iterate through the list, if it's a list.
+	auto librariesValue = root.value("libraries");
+	if(!librariesValue.isArray())
+		return fullVersion;
+	
+	QJsonArray libList = root.value("libraries").toArray();
+	for (auto libVal : libList)
+	{
+		if (!libVal.isObject())
+		{
+			continue;
+		}
+		
+		QJsonObject libObj = libVal.toObject();
+		
+		// Library name
+		auto nameVal = libObj.value("name");
+		if(!nameVal.isString())
+			continue;
+		QSharedPointer<Library> library(new Library(nameVal.toString()));
+		
+		// Extract excludes (if any)
+		auto extractVal = libObj.value("extract");
+		if(extractVal.isObject())
+		{
+			QStringList excludes;
+			auto extractObj = extractVal.toObject();
+			auto excludesVal = extractObj.value("exclude");
+			if(!excludesVal.isArray())
+				goto SKIP_EXTRACTS;
+			auto excludesList = excludesVal.toArray();
+			for(auto excludeVal : excludesList)
+			{
+				if(excludeVal.isString())
+					excludes.append(excludeVal.toString());
+			}
+			library->extract_excludes = excludes;
+		}
+		SKIP_EXTRACTS:
+		
+		auto nativesVal = libObj.value("natives");
+		if(nativesVal.isObject())
+		{
+			library->setIsNative();
+			auto nativesObj = nativesVal.toObject();
+			auto iter = nativesObj.begin();
+			while(iter != nativesObj.end())
+			{
+				auto osType = OpSys_fromString(iter.key());
+				if(osType == Os_Other)
+					continue;
+				if(!iter.value().isString())
+					continue;
+				library->addNative(osType, iter.value().toString());
+				iter++;
+			}
+		}
+		library->setRules(parse4rules(libObj));
+		library->finalize();
+		fullVersion->libraries.append(library);
+	}
+	return fullVersion;
+}
+
+QSharedPointer<FullVersion> FullVersionFactory::parse(QByteArray data)
+{
+	QSharedPointer<FullVersion> readVersion(new FullVersion());
+	
+	QJsonParseError jsonError;
+	QJsonDocument jsonDoc = QJsonDocument::fromJson(data, &jsonError);
+	
+	if (jsonError.error != QJsonParseError::NoError)
+	{
+		error_string = QString( "Error reading version file :") + " " + jsonError.errorString();
+		m_error = FullVersionFactory::ParseError;
+		return QSharedPointer<FullVersion>();
+	}
+	
+	if(!jsonDoc.isObject())
+	{
+		error_string = "Error reading version file.";
+		m_error = FullVersionFactory::ParseError;
+		return QSharedPointer<FullVersion>();
+	}
+	QJsonObject root = jsonDoc.object();
+	
+	readVersion->minimumLauncherVersion = root.value("minimumLauncherVersion").toDouble();
+	switch(readVersion->minimumLauncherVersion)
+	{
+		case 1:
+		case 2:
+		case 3:
+		case 4:
+			return parse4(root, readVersion);
+		// ADD MORE HERE :D
+		default:
+			error_string = "Version file was for an unrecognized launcher version. RIP";
+			m_error = FullVersionFactory::UnsupportedVersion;
+			return QSharedPointer<FullVersion>();
+	}
+}
+
+
+FullVersionFactory::FullVersionFactory()
+{
+	m_error = FullVersionFactory::AllOK;
+	legacyWhitelist.append("1.5.1");
+	legacyWhitelist.append("1.5.2");
+}
diff --git a/backend/VersionFactory.h b/backend/VersionFactory.h
new file mode 100644
index 00000000..60e5c983
--- /dev/null
+++ b/backend/VersionFactory.h
@@ -0,0 +1,25 @@
+#pragma once
+#include <QtCore>
+
+struct FullVersion;
+class Rule;
+
+class FullVersionFactory
+{
+public:
+	enum Error
+	{
+		AllOK, // all parsed OK
+		ParseError, // the file was corrupted somehow
+		UnsupportedVersion // the file was meant for a launcher version we don't support (yet)
+	} m_error;
+	QString error_string;
+
+public:
+	FullVersionFactory();
+	QSharedPointer<FullVersion> parse(QByteArray data);
+private:
+	QSharedPointer<FullVersion> parse4(QJsonObject root, QSharedPointer<FullVersion> product);
+	QList<QSharedPointer<Rule> > parse4rules(QJsonObject & baseObj);
+	QStringList legacyWhitelist;
+};
\ No newline at end of file
diff --git a/backend/libmmc_config.h b/backend/libmmc_config.h
new file mode 100644
index 00000000..6d967f5f
--- /dev/null
+++ b/backend/libmmc_config.h
@@ -0,0 +1,24 @@
+/* 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 <QtCore/QtGlobal>
+
+#ifdef LIBMULTIMC_LIBRARY
+#  define LIBMULTIMC_EXPORT Q_DECL_EXPORT
+#else
+#  define LIBMULTIMC_EXPORT Q_DECL_IMPORT
+#endif
diff --git a/backend/lists/InstVersionList.cpp b/backend/lists/InstVersionList.cpp
new file mode 100644
index 00000000..c65770a9
--- /dev/null
+++ b/backend/lists/InstVersionList.cpp
@@ -0,0 +1,129 @@
+/* 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 "InstVersionList.h"
+#include "InstanceVersion.h"
+
+InstVersionList::InstVersionList(QObject *parent) :
+	QAbstractListModel(parent)
+{
+}
+
+const InstVersion *InstVersionList::findVersion(const QString &descriptor)
+{
+	for (int i = 0; i < count(); i++)
+	{
+		if (at(i)->descriptor() == descriptor)
+			return at(i);
+	}
+	return NULL;
+}
+
+const InstVersion *InstVersionList::getLatestStable() const
+{
+	if (count() <= 0)
+		return NULL;
+	else
+		return at(0);
+}
+
+QVariant InstVersionList::data(const QModelIndex &index, int role) const
+{
+	if (!index.isValid())
+		return QVariant();
+	
+	if (index.row() > count())
+		return QVariant();
+	
+	
+	const InstVersion *version = at(index.row());
+	
+	switch (role)
+	{
+	case Qt::DisplayRole:
+		switch (index.column())
+		{
+		case NameColumn:
+			return version->name();
+			
+		case TypeColumn:
+			return version->typeName();
+			
+		case TimeColumn:
+			return version->timestamp();
+			
+		default:
+			return QVariant();
+		}
+		
+	case Qt::ToolTipRole:
+		return version->descriptor();
+		
+	case VersionPointerRole:
+		return qVariantFromValue((void *) version);
+		
+	default:
+		return QVariant();
+	}
+}
+
+QVariant InstVersionList::headerData(int section, Qt::Orientation orientation, int role) const
+{
+	switch (role)
+	{
+	case Qt::DisplayRole:
+		switch (section)
+		{
+		case NameColumn:
+			return "Name";
+			
+		case TypeColumn:
+			return "Type";
+			
+		case TimeColumn:
+			return "Time";
+		
+		default:
+			return QVariant();
+		}
+		
+	case Qt::ToolTipRole:
+		switch (section)
+		{
+		case NameColumn:
+			return "The name of the version.";
+			
+		case TypeColumn:
+			return "The version's type.";
+		
+		default:
+			return QVariant();
+		}
+		
+	default:
+		return QVariant();
+	}
+}
+
+int InstVersionList::rowCount(const QModelIndex &parent) const
+{
+	// Return count
+	return count();
+}
+
+int InstVersionList::columnCount(const QModelIndex &parent) const
+{
+	return 2;
+}
diff --git a/backend/lists/InstVersionList.h b/backend/lists/InstVersionList.h
new file mode 100644
index 00000000..97e00383
--- /dev/null
+++ b/backend/lists/InstVersionList.h
@@ -0,0 +1,121 @@
+/* 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 <QObject>
+#include <QVariant>
+#include <QAbstractListModel>
+
+#include "libmmc_config.h"
+
+class InstVersion;
+class Task;
+
+/*!
+ * \brief Class that each instance type's version list derives from. 
+ * Version lists are the lists that keep track of the available game versions 
+ * for that instance. This list will not be loaded on startup. It will be loaded 
+ * when the list's load function is called. Before using the version list, you
+ * should check to see if it has been loaded yet and if not, load the list.
+ * 
+ * Note that this class also inherits from QAbstractListModel. Methods from that
+ * class determine how this version list shows up in a list view. Said methods
+ * all have a default implementation, but they can be overridden by plugins to
+ * change the behavior of the list.
+ */
+class LIBMULTIMC_EXPORT InstVersionList : public QAbstractListModel
+{
+	Q_OBJECT
+public:
+	enum ModelRoles
+	{
+		VersionPointerRole = 0x34B1CB48
+	};
+	
+	enum VListColumns
+	{
+		// First column - Name
+		NameColumn = 0,
+		
+		// Second column - Type
+		TypeColumn,
+		
+		// Third column - Timestamp
+		TimeColumn
+	};
+	
+	explicit InstVersionList(QObject *parent = 0);
+	
+	/*!
+	 * \brief Gets a task that will reload the version islt.
+	 * Simply execute the task to load the list.
+	 * The task returned by this function should reset the model when it's done.
+	 * \return A pointer to a task that reloads the version list.
+	 */
+	virtual Task *getLoadTask() = 0;
+	
+	//! Checks whether or not the list is loaded. If this returns false, the list should be loaded.
+	virtual bool isLoaded() = 0;
+	
+	//! Gets the version at the given index.
+	virtual const InstVersion *at(int i) const = 0;
+	
+	//! Returns the number of versions in the list.
+	virtual int count() const = 0;
+	
+	
+	//////// List Model Functions ////////
+	virtual QVariant data(const QModelIndex &index, int role) const;
+	virtual QVariant headerData(int section, Qt::Orientation orientation, int role) const;
+	virtual int rowCount(const QModelIndex &parent) const;
+	virtual int columnCount(const QModelIndex &parent) const;
+	
+	
+	/*!
+	 * \brief Finds a version by its descriptor.
+	 * \param The descriptor of the version to find.
+	 * \return A const pointer to the version with the given descriptor. NULL if
+	 * one doesn't exist.
+	 */
+	virtual const InstVersion *findVersion(const QString &descriptor);
+	
+	/*!
+	 * \brief Gets the latest stable version of this instance type.
+	 * This is the version that will be selected by default.
+	 * By default, this is simply the first version in the list.
+	 */
+	virtual const InstVersion *getLatestStable() const;
+	
+	/*!
+	 * Sorts the version list.
+	 */
+	virtual void sort() = 0;
+	
+protected slots:
+	/*!
+	 * Updates this list with the given list of versions.
+	 * This is done by copying each version in the given list and inserting it
+	 * into this one.
+	 * We need to do this so that we can set the parents of the versions are set to this
+	 * version list. This can't be done in the load task, because the versions the load
+	 * task creates are on the load task's thread and Qt won't allow their parents
+	 * to be set to something created on another thread.
+	 * To get around that problem, we invoke this method on the GUI thread, which
+	 * then copies the versions and sets their parents correctly.
+	 * \param versions List of versions whose parents should be set.
+	 */
+	virtual void updateListData(QList<InstVersion *> versions) = 0;
+};
diff --git a/backend/lists/InstanceList.cpp b/backend/lists/InstanceList.cpp
new file mode 100644
index 00000000..101d52c5
--- /dev/null
+++ b/backend/lists/InstanceList.cpp
@@ -0,0 +1,232 @@
+/* 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 <QDir>
+#include <QFile>
+#include <QDirIterator>
+#include <QThread>
+#include <QTextStream>
+#include <QJsonDocument>
+#include <QJsonObject>
+#include <QJsonArray>
+
+#include "lists/InstanceList.h"
+#include "BaseInstance.h"
+#include "InstanceFactory.h"
+
+#include "pathutils.h"
+
+const static int GROUP_FILE_FORMAT_VERSION = 1;
+
+InstanceList::InstanceList(const QString &instDir, QObject *parent) :
+	QObject(parent), m_instDir("instances")
+{
+	
+}
+
+void InstanceList::loadGroupList(QMap<QString, QString> & groupMap)
+{
+	QString groupFileName = m_instDir + "/instgroups.json";
+	
+	// if there's no group file, fail
+	if(!QFileInfo(groupFileName).exists())
+		return;
+	
+	QFile groupFile(groupFileName);
+	
+	// if you can't open the file, fail
+	if (!groupFile.open(QIODevice::ReadOnly))
+	{
+		// An error occurred. Ignore it.
+		qDebug("Failed to read instance group file.");
+		return;
+	}
+	
+	QTextStream in(&groupFile);
+	QString jsonStr = in.readAll();
+	groupFile.close();
+	
+	QJsonParseError error;
+	QJsonDocument jsonDoc = QJsonDocument::fromJson(jsonStr.toUtf8(), &error);
+	
+	// if the json was bad, fail
+	if (error.error != QJsonParseError::NoError)
+	{
+		qWarning(QString("Failed to parse instance group file: %1 at offset %2").
+					arg(error.errorString(), QString::number(error.offset)).toUtf8());
+		return;
+	}
+	
+	// if the root of the json wasn't an object, fail
+	if (!jsonDoc.isObject())
+	{
+		qWarning("Invalid group file. Root entry should be an object.");
+		return;
+	}
+	
+	QJsonObject rootObj = jsonDoc.object();
+	
+	// Make sure the format version matches, otherwise fail.
+	if (rootObj.value("formatVersion").toVariant().toInt() != GROUP_FILE_FORMAT_VERSION)
+		return;
+	
+	// Get the groups. if it's not an object, fail
+	if (!rootObj.value("groups").isObject())
+	{
+		qWarning("Invalid group list JSON: 'groups' should be an object.");
+		return;
+	}
+		
+	// Iterate through all the groups.
+	QJsonObject groupMapping = rootObj.value("groups").toObject();
+	for (QJsonObject::iterator iter = groupMapping.begin(); iter != groupMapping.end(); iter++)
+	{
+		QString groupName = iter.key();
+		
+		// If not an object, complain and skip to the next one.
+		if (!iter.value().isObject())
+		{
+			qWarning(QString("Group '%1' in the group list should "
+								"be an object.").arg(groupName).toUtf8());
+			continue;
+		}
+		
+		QJsonObject groupObj = iter.value().toObject();
+		if (!groupObj.value("instances").isArray())
+		{
+			qWarning(QString("Group '%1' in the group list is invalid. "
+								"It should contain an array "
+								"called 'instances'.").arg(groupName).toUtf8());
+			continue;
+		}
+		
+		// Iterate through the list of instances in the group.
+		QJsonArray instancesArray = groupObj.value("instances").toArray();
+		
+		for (QJsonArray::iterator iter2 = instancesArray.begin(); 
+				iter2 != instancesArray.end(); iter2++)
+		{
+			groupMap[(*iter2).toString()] = groupName;
+		}
+	}
+}
+
+InstanceList::InstListError InstanceList::loadList()
+{
+	// load the instance groups
+	QMap<QString, QString> groupMap;
+	loadGroupList(groupMap);
+	
+	m_instances.clear();
+	QDir dir(m_instDir);
+	QDirIterator iter(dir);
+	while (iter.hasNext())
+	{
+		QString subDir = iter.next();
+		if (!QFileInfo(PathCombine(subDir, "instance.cfg")).exists())
+			continue;
+		
+		BaseInstance *instPtr = NULL;
+		auto &loader = InstanceFactory::get();
+		auto error = loader.loadInstance(instPtr, subDir);
+		
+		switch(error)
+		{
+			case InstanceFactory::NoLoadError:
+				break;
+			case InstanceFactory::NotAnInstance:
+				break;
+		}
+		
+		if (error != InstanceFactory::NoLoadError &&
+			error != InstanceFactory::NotAnInstance)
+		{
+			QString errorMsg = QString("Failed to load instance %1: ").
+					arg(QFileInfo(subDir).baseName()).toUtf8();
+			
+			switch (error)
+			{
+			default:
+				errorMsg += QString("Unknown instance loader error %1").
+						arg(error);
+				break;
+			}
+			qDebug(errorMsg.toUtf8());
+		}
+		else if (!instPtr)
+		{
+			qDebug(QString("Error loading instance %1. Instance loader returned null.").
+					arg(QFileInfo(subDir).baseName()).toUtf8());
+		}
+		else
+		{
+			QSharedPointer<BaseInstance> inst(instPtr);
+			auto iter = groupMap.find(inst->id());
+			if(iter != groupMap.end())
+			{
+				inst->setGroup((*iter));
+			}
+			qDebug(QString("Loaded instance %1").arg(inst->name()).toUtf8());
+			inst->setParent(this);
+			m_instances.append(inst);
+			connect(instPtr, SIGNAL(propertiesChanged(BaseInstance*)),this, SLOT(propertiesChanged(BaseInstance*)));
+		}
+	}
+	emit invalidated();
+	return NoError;
+}
+
+/// Clear all instances. Triggers notifications.
+void InstanceList::clear()
+{
+	m_instances.clear();
+	emit invalidated();
+};
+
+/// Add an instance. Triggers notifications, returns the new index
+int InstanceList::add(InstancePtr t)
+{
+	m_instances.append(t);
+	emit instanceAdded(count() - 1);
+	return count() - 1;
+}
+
+InstancePtr InstanceList::getInstanceById(QString instId)
+{
+	QListIterator<InstancePtr> iter(m_instances);
+	InstancePtr inst;
+	while(iter.hasNext())
+	{
+		inst = iter.next();
+		if (inst->id() == instId)
+			break;
+	}
+	if (inst->id() != instId)
+		return InstancePtr();
+	else
+		return iter.peekPrevious();
+}
+
+void InstanceList::propertiesChanged(BaseInstance * inst)
+{
+	for(int i = 0; i < m_instances.count(); i++)
+	{
+		if(inst == m_instances[i].data())
+		{
+			emit instanceChanged(i);
+			break;
+		}
+	}
+}
diff --git a/backend/lists/InstanceList.h b/backend/lists/InstanceList.h
new file mode 100644
index 00000000..8c9965e5
--- /dev/null
+++ b/backend/lists/InstanceList.h
@@ -0,0 +1,92 @@
+/* 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 <QObject>
+#include <QSharedPointer>
+
+#include "BaseInstance.h"
+#include "libmmc_config.h"
+
+class BaseInstance;
+
+class LIBMULTIMC_EXPORT InstanceList : public QObject
+{
+	Q_OBJECT
+private:
+	/*!
+	 * \brief Get the instance groups
+	 */
+	void loadGroupList(QMap<QString, QString> & groupList);
+	
+public:
+	explicit InstanceList(const QString &instDir, QObject *parent = 0);
+	
+	/*!
+	 * \brief Error codes returned by functions in the InstanceList class.
+	 * NoError Indicates that no error occurred.
+	 * UnknownError indicates that an unspecified error occurred.
+	 */
+	enum InstListError
+	{
+		NoError = 0,
+		UnknownError
+	};
+	
+	QString instDir() const { return m_instDir; }
+	
+	/*!
+	 * \brief Loads the instance list. Triggers notifications.
+	 */
+	InstListError loadList();
+	
+	/*!
+	 * \brief Get the instance at index
+	 */
+	InstancePtr at(int i) const
+	{
+		return m_instances.at(i);
+	};
+	
+	/*!
+	 * \brief Get the count of loaded instances
+	 */
+	int count() const
+	{
+		return m_instances.count();
+	};
+	
+	/// Clear all instances. Triggers notifications.
+	void clear();
+	
+	/// Add an instance. Triggers notifications, returns the new index
+	int add(InstancePtr t);
+	
+	/// Get an instance by ID
+	InstancePtr getInstanceById (QString id);
+
+signals:
+	void instanceAdded(int index);
+	void instanceChanged(int index);
+	void invalidated();
+	
+private slots:
+	void propertiesChanged(BaseInstance * inst);
+	
+protected:
+	QString m_instDir;
+	QList< InstancePtr > m_instances;
+};
diff --git a/backend/lists/LwjglVersionList.cpp b/backend/lists/LwjglVersionList.cpp
new file mode 100644
index 00000000..824d0906
--- /dev/null
+++ b/backend/lists/LwjglVersionList.cpp
@@ -0,0 +1,204 @@
+/* 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 "LwjglVersionList.h"
+
+#include <QtNetwork>
+
+#include <QtXml>
+
+#include <QRegExp>
+
+#define RSS_URL "http://sourceforge.net/api/file/index/project-id/58488/mtime/desc/rss"
+
+LWJGLVersionList mainVersionList;
+
+LWJGLVersionList &LWJGLVersionList::get()
+{
+	return mainVersionList;
+}
+
+
+LWJGLVersionList::LWJGLVersionList(QObject *parent) :
+	QAbstractListModel(parent)
+{
+	setLoading(false);
+}
+
+QVariant LWJGLVersionList::data(const QModelIndex &index, int role) const
+{
+	if (!index.isValid())
+		return QVariant();
+	
+	if (index.row() > count())
+		return QVariant();
+	
+	const PtrLWJGLVersion version = at(index.row());
+	
+	switch (role)
+	{
+	case Qt::DisplayRole:
+		return version->name();
+		
+	case Qt::ToolTipRole:
+		return version->url().toString();
+		
+	default:
+		return QVariant();
+	}
+}
+
+QVariant LWJGLVersionList::headerData(int section, Qt::Orientation orientation, int role) const
+{
+	switch (role)
+	{
+	case Qt::DisplayRole:
+		return "Version";
+		
+	case Qt::ToolTipRole:
+		return "LWJGL version name.";
+		
+	default:
+		return QVariant();
+	}
+}
+
+int LWJGLVersionList::columnCount(const QModelIndex &parent) const
+{
+	return 1;
+}
+
+bool LWJGLVersionList::isLoading() const
+{
+	return m_loading;
+}
+
+void LWJGLVersionList::loadList()
+{
+	Q_ASSERT_X(!m_loading, "loadList", "list is already loading (m_loading is true)");
+	
+	setLoading(true);
+	reply = netMgr.get(QNetworkRequest(QUrl(RSS_URL)));
+	connect(reply, SIGNAL(finished()), SLOT(netRequestComplete()));
+}
+
+inline QDomElement getDomElementByTagName(QDomElement parent, QString tagname)
+{
+	QDomNodeList elementList = parent.elementsByTagName(tagname);
+	if (elementList.count())
+		return elementList.at(0).toElement();
+	else
+		return QDomElement();
+}
+
+void LWJGLVersionList::netRequestComplete()
+{
+	if (reply->error() == QNetworkReply::NoError)
+	{
+		QRegExp lwjglRegex("lwjgl-(([0-9]\\.?)+)\\.zip");
+		Q_ASSERT_X(lwjglRegex.isValid(), "load LWJGL list", 
+				   "LWJGL regex is invalid");
+		
+		QDomDocument doc;
+		
+		QString xmlErrorMsg;
+		int errorLine;
+		if (!doc.setContent(reply->readAll(), false, &xmlErrorMsg, &errorLine))
+		{
+			failed("Failed to load LWJGL list. XML error: " + xmlErrorMsg +
+				   " at line " + QString::number(errorLine));
+			setLoading(false);
+			return;
+		}
+		
+		QDomNodeList items = doc.elementsByTagName("item");
+		
+		QList<PtrLWJGLVersion> tempList;
+		
+		for (int i = 0; i < items.length(); i++)
+		{
+			Q_ASSERT_X(items.at(i).isElement(), "load LWJGL list",
+					   "XML element isn't an element... wat?");
+			
+			QDomElement linkElement = getDomElementByTagName(items.at(i).toElement(), "link");
+			if (linkElement.isNull())
+			{
+				qWarning() << "Link element" << i << "in RSS feed doesn't exist! Skipping.";
+				continue;
+			}
+			
+			QString link = linkElement.text();
+			
+			// Make sure it's a download link.
+			if (link.endsWith("/download") && link.contains(lwjglRegex))
+			{
+				QString name = link.mid(lwjglRegex.indexIn(link));
+				// Subtract 4 here to remove the .zip file extension.
+				name = name.left(lwjglRegex.matchedLength() - 4);
+				
+				QUrl url(link);
+				if (!url.isValid())
+				{
+					qWarning() << "LWJGL version URL isn't valid:" << link << "Skipping.";
+					continue;
+				}
+				
+				tempList.append(LWJGLVersion::Create(name, link));
+			}
+		}
+		
+		beginResetModel();
+		m_vlist.swap(tempList);
+		endResetModel();
+		
+		qDebug("Loaded LWJGL list.");
+		finished();
+	}
+	else
+	{
+		failed("Failed to load LWJGL list. Network error: " + reply->errorString());
+	}
+	
+	setLoading(false);
+	reply->deleteLater();
+}
+
+const PtrLWJGLVersion LWJGLVersionList::getVersion(const QString &versionName)
+{
+	for (int i = 0; i < count(); i++)
+	{
+		if (at(i)->name() == versionName)
+			return at(i);
+	}
+	return PtrLWJGLVersion();
+}
+
+
+void LWJGLVersionList::failed(QString msg)
+{
+	qWarning() << msg;
+	emit loadListFailed(msg);
+}
+
+void LWJGLVersionList::finished()
+{
+	emit loadListFinished();
+}
+
+void LWJGLVersionList::setLoading(bool loading)
+{
+	m_loading = loading;
+	emit loadingStateUpdated(m_loading);
+}
diff --git a/backend/lists/LwjglVersionList.h b/backend/lists/LwjglVersionList.h
new file mode 100644
index 00000000..f3e7799a
--- /dev/null
+++ b/backend/lists/LwjglVersionList.h
@@ -0,0 +1,132 @@
+/* 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 <QObject>
+#include <QAbstractListModel>
+#include <QSharedPointer>
+#include <QUrl>
+
+#include <QNetworkAccessManager>
+#include <QNetworkReply>
+
+#include "libmmc_config.h"
+
+class LWJGLVersion;
+typedef QSharedPointer<LWJGLVersion> PtrLWJGLVersion;
+
+class LIBMULTIMC_EXPORT LWJGLVersion : public QObject
+{
+	Q_OBJECT
+	
+	/*!
+	 * The name of the LWJGL version.
+	 */
+	Q_PROPERTY(QString name READ name)
+	
+	/*!
+	 * The URL for this version of LWJGL.
+	 */
+	Q_PROPERTY(QUrl url READ url)
+	
+	LWJGLVersion(const QString &name, const QUrl &url, QObject *parent = 0) :
+		QObject(parent), m_name(name), m_url(url) { }
+public:
+	
+	static PtrLWJGLVersion Create(const QString &name, const QUrl &url, QObject *parent = 0)
+	{
+		return PtrLWJGLVersion(new LWJGLVersion(name, url, parent));
+	};
+	
+	QString name() const { return m_name; }
+	
+	QUrl url() const { return m_url; }
+	
+protected:
+	QString m_name;
+	QUrl m_url;
+};
+
+class LIBMULTIMC_EXPORT LWJGLVersionList : public QAbstractListModel
+{
+	Q_OBJECT
+public:
+	explicit LWJGLVersionList(QObject *parent = 0);
+	
+	static LWJGLVersionList &get();
+	
+	bool isLoaded() { return m_vlist.length() > 0; }
+	
+	const PtrLWJGLVersion getVersion(const QString &versionName);
+	PtrLWJGLVersion at(int index) { return m_vlist[index]; }
+	const PtrLWJGLVersion at(int index) const { return m_vlist[index]; }
+	
+	int count() const { return m_vlist.length(); }
+	
+	virtual QVariant data(const QModelIndex &index, int role) const;
+	virtual QVariant headerData(int section, Qt::Orientation orientation, int role) const;
+	virtual int rowCount(const QModelIndex &parent) const { return count(); }
+	virtual int columnCount(const QModelIndex &parent) const;
+	
+	virtual bool isLoading() const;
+	virtual bool errored() const { return m_errored; }
+	
+	virtual QString lastErrorMsg() const { return m_lastErrorMsg; }
+	
+public slots:
+	/*!
+	 * Loads the version list.
+	 * This is done asynchronously. On success, the loadListFinished() signal will
+	 * be emitted. The list model will be reset as well, resulting in the modelReset() 
+	 * signal being emitted. Note that the model will be reset before loadListFinished() is emitted.
+	 * If loading the list failed, the loadListFailed(QString msg),
+	 * signal will be emitted.
+	 */
+	virtual void loadList();
+	
+signals:
+	/*!
+	 * Emitted when the list either starts or finishes loading.
+	 * \param loading Whether or not the list is loading.
+	 */
+	void loadingStateUpdated(bool loading);
+	
+	void loadListFinished();
+	
+	void loadListFailed(QString msg);
+	
+private:
+	QList<PtrLWJGLVersion> m_vlist;
+	
+	QNetworkReply *m_netReply;
+	
+	QNetworkAccessManager netMgr;
+	QNetworkReply *reply;
+	
+	bool m_loading;
+	bool m_errored;
+	QString m_lastErrorMsg;
+	
+	void failed(QString msg);
+	
+	void finished();
+	
+	void setLoading(bool loading);
+	
+private slots:
+	virtual void netRequestComplete();
+};
+
diff --git a/backend/lists/MinecraftVersionList.cpp b/backend/lists/MinecraftVersionList.cpp
new file mode 100644
index 00000000..d576397f
--- /dev/null
+++ b/backend/lists/MinecraftVersionList.cpp
@@ -0,0 +1,528 @@
+/* Copyright 2013 Andrew Okin
+ *
+ * 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 "MinecraftVersionList.h"
+
+#include <QDebug>
+
+#include <QtXml>
+
+#include <QJsonDocument>
+#include <QJsonObject>
+#include <QJsonArray>
+#include <QJsonValue>
+#include <QJsonParseError>
+
+#include <QtAlgorithms>
+
+#include <QtNetwork>
+
+#include "netutils.h"
+
+#define MCVLIST_URLBASE "http://s3.amazonaws.com/Minecraft.Download/versions/"
+#define ASSETS_URLBASE "http://assets.minecraft.net/"
+#define MCN_URLBASE "http://sonicrules.org/mcnweb.py"
+
+MinecraftVersionList mcVList;
+
+MinecraftVersionList::MinecraftVersionList(QObject *parent) :
+	InstVersionList(parent)
+{
+	
+}
+
+Task *MinecraftVersionList::getLoadTask()
+{
+	return new MCVListLoadTask(this);
+}
+
+bool MinecraftVersionList::isLoaded()
+{
+	return m_loaded;
+}
+
+const InstVersion *MinecraftVersionList::at(int i) const
+{
+	return m_vlist.at(i);
+}
+
+int MinecraftVersionList::count() const
+{
+	return m_vlist.count();
+}
+
+void MinecraftVersionList::printToStdOut() const
+{
+	qDebug() << "---------------- Version List ----------------";
+	
+	for (int i = 0; i < m_vlist.count(); i++)
+	{
+		MinecraftVersion *version = qobject_cast<MinecraftVersion *>(m_vlist.at(i));
+		
+		if (!version)
+			continue;
+		
+		qDebug() << "Version " << version->name();
+		qDebug() << "\tDownload: " << version->downloadURL();
+		qDebug() << "\tTimestamp: " << version->timestamp();
+		qDebug() << "\tType: " << version->typeName();
+		qDebug() << "----------------------------------------------";
+	}
+}
+
+bool cmpVersions(const InstVersion *first, const InstVersion *second)
+{
+	return !first->isLessThan(*second);
+}
+
+void MinecraftVersionList::sort()
+{
+	beginResetModel();
+	qSort(m_vlist.begin(), m_vlist.end(), cmpVersions);
+	endResetModel();
+}
+
+InstVersion *MinecraftVersionList::getLatestStable() const
+{
+	for (int i = 0; i < m_vlist.length(); i++)
+	{
+		if (((MinecraftVersion *)m_vlist.at(i))->versionType() == MinecraftVersion::CurrentStable)
+		{
+			return m_vlist.at(i);
+		}
+	}
+	return NULL;
+}
+
+MinecraftVersionList &MinecraftVersionList::getMainList()
+{
+	return mcVList;
+}
+
+void MinecraftVersionList::updateListData(QList<InstVersion *> versions)
+{
+	// First, we populate a temporary list with the copies of the versions.
+	QList<InstVersion *> tempList;
+	for (int i = 0; i < versions.length(); i++)
+	{
+		InstVersion *version = versions[i]->copyVersion(this);
+		Q_ASSERT(version != NULL);
+		tempList.append(version);
+	}
+	
+	// Now we swap the temporary list into the actual version list.
+	// This applies our changes to the version list immediately and still gives us 
+	// access to the old version list so that we can delete the objects in it and 
+	// free their memory. By doing this, we cause the version list to update as 
+	// quickly as possible.
+	beginResetModel();
+	m_vlist.swap(tempList);
+	m_loaded = true;
+	endResetModel();
+	
+	// We called swap, so all the data that was in the version list previously is now in 
+	// tempList (and vice-versa). Now we just free the memory.
+	while (!tempList.isEmpty())
+		delete tempList.takeFirst();
+	
+	// NOW SORT!!
+	sort();
+}
+
+inline QDomElement getDomElementByTagName(QDomElement parent, QString tagname)
+{
+	QDomNodeList elementList = parent.elementsByTagName(tagname);
+	if (elementList.count())
+		return elementList.at(0).toElement();
+	else
+		return QDomElement();
+}
+
+inline QDateTime timeFromS3Time(QString str)
+{
+	return QDateTime::fromString(str, Qt::ISODate);
+}
+
+
+MCVListLoadTask::MCVListLoadTask(MinecraftVersionList *vlist)
+{
+	m_list = vlist;
+	m_currentStable = NULL;
+	processedAssetsReply = false;
+	processedMCNReply = false;
+	processedMCVListReply = false;
+}
+
+MCVListLoadTask::~MCVListLoadTask()
+{
+//	delete netMgr;
+}
+
+void MCVListLoadTask::executeTask()
+{
+	setSubStatus();
+	
+	QNetworkAccessManager networkMgr;
+	netMgr = &networkMgr;
+	
+	if (!loadFromVList())
+	{
+		qDebug() << "Failed to load from Mojang version list.";
+	}
+	if (!loadFromAssets())
+	{
+		qDebug() << "Failed to load assets version list.";
+	}
+	if (!loadMCNostalgia())
+	{
+		qDebug() << "Failed to load MCNostalgia version list.";
+	}
+	finalize();
+}
+
+void MCVListLoadTask::setSubStatus(const QString msg)
+{
+	if (msg.isEmpty())
+		setStatus("Loading instance version list...");
+	else
+		setStatus("Loading instance version list: " + msg);
+}
+
+// FIXME: we should have a local cache of the version list and a local cache of version data
+bool MCVListLoadTask::loadFromVList()
+{
+	QNetworkReply *vlistReply = netMgr->get(QNetworkRequest(QUrl(QString(MCVLIST_URLBASE) + 
+																 "versions.json")));
+	NetUtils::waitForNetRequest(vlistReply);
+	
+	switch (vlistReply->error())
+	{
+	case QNetworkReply::NoError:
+	{
+		QJsonParseError jsonError;
+		QJsonDocument jsonDoc = QJsonDocument::fromJson(vlistReply->readAll(), &jsonError);
+		
+		if (jsonError.error == QJsonParseError::NoError)
+		{
+			Q_ASSERT_X(jsonDoc.isObject(), "loadFromVList", "jsonDoc is not an object");
+			
+			QJsonObject root = jsonDoc.object();
+			
+			// Get the ID of the latest release and the latest snapshot.
+			Q_ASSERT_X(root.value("latest").isObject(), "loadFromVList", 
+					   "version list is missing 'latest' object");
+			QJsonObject latest = root.value("latest").toObject();
+			
+			QString latestReleaseID = latest.value("release").toString("");
+			QString latestSnapshotID = latest.value("snapshot").toString("");
+			Q_ASSERT_X(!latestReleaseID.isEmpty(), "loadFromVList", "latest release field is missing");
+			Q_ASSERT_X(!latestSnapshotID.isEmpty(), "loadFromVList", "latest snapshot field is missing");
+			
+			// Now, get the array of versions.
+			Q_ASSERT_X(root.value("versions").isArray(), "loadFromVList", 
+					   "version list object is missing 'versions' array");
+			QJsonArray versions = root.value("versions").toArray();
+			
+			for (int i = 0; i < versions.count(); i++)
+			{
+				// Load the version info.
+				Q_ASSERT_X(versions[i].isObject(), "loadFromVList",
+						   QString("in versions array, index %1 is not an object").
+						   arg(i).toUtf8());
+				QJsonObject version = versions[i].toObject();
+				
+				QString versionID = version.value("id").toString("");
+				QString versionTimeStr = version.value("releaseTime").toString("");
+				QString versionTypeStr = version.value("type").toString("");
+				
+				Q_ASSERT_X(!versionID.isEmpty(), "loadFromVList", 
+						   QString("in versions array, index %1's \"id\" field is not a valid string").
+						   arg(i).toUtf8());
+				Q_ASSERT_X(!versionTimeStr.isEmpty(), "loadFromVList",
+						   QString("in versions array, index %1's \"time\" field is not a valid string").
+						   arg(i).toUtf8());
+				Q_ASSERT_X(!versionTypeStr.isEmpty(), "loadFromVList", 
+						   QString("in versions array, index %1's \"type\" field is not a valid string").
+						   arg(i).toUtf8());
+				
+				
+				// Now, process that info and add the version to the list.
+				
+				// Parse the timestamp.
+				QDateTime versionTime = timeFromS3Time(versionTimeStr);
+				
+				Q_ASSERT_X(versionTime.isValid(), "loadFromVList",
+						   QString("in versions array, index %1's timestamp failed to parse").
+						   arg(i).toUtf8());
+				
+				// Parse the type.
+				MinecraftVersion::VersionType versionType;
+				if (versionTypeStr == "release")
+				{
+					// Check if this version is the current stable version.
+					if (versionID == latestReleaseID)
+						versionType = MinecraftVersion::CurrentStable;
+					else
+						versionType = MinecraftVersion::Stable;
+				}
+				else if(versionTypeStr == "snapshot")
+				{
+					versionType = MinecraftVersion::Snapshot;
+				}
+				else
+				{
+					// we don't know what to do with this...
+					continue;
+				}
+				
+				// Get the download URL.
+				QString dlUrl = QString(MCVLIST_URLBASE) + versionID + "/";
+				
+				
+				// Now, we construct the version object and add it to the list.
+				MinecraftVersion *mcVersion = new MinecraftVersion(
+							versionID, versionID, versionTime.toMSecsSinceEpoch(),
+							dlUrl, "");
+				mcVersion->setVersionSource(MinecraftVersion::Launcher16);
+				mcVersion->setVersionType(versionType);
+				tempList.append(mcVersion);
+			}
+		}
+		else
+		{
+			qDebug() << "Error parsing version list JSON:" << jsonError.errorString();
+		}
+		
+		break;
+	}
+		
+	default:
+		// TODO: Network error handling.
+		qDebug() << "Failed to load Minecraft main version list" << vlistReply->errorString();
+		break;
+	}
+	
+	return true;
+}
+
+bool MCVListLoadTask::loadFromAssets()
+{
+	setSubStatus("Loading versions from assets.minecraft.net...");
+	
+	bool succeeded = false;
+	
+	QNetworkReply *assetsReply = netMgr->get(QNetworkRequest(QUrl(ASSETS_URLBASE)));
+	NetUtils::waitForNetRequest(assetsReply);
+	
+	switch (assetsReply->error())
+	{
+	case QNetworkReply::NoError:
+	{
+		// Get the XML string.
+		QString xmlString = assetsReply->readAll();
+		
+		QString xmlErrorMsg;
+		
+		QDomDocument doc;
+		if (!doc.setContent(xmlString, false, &xmlErrorMsg))
+		{
+			// TODO: Display error message to the user.
+			qDebug() << "Failed to process assets.minecraft.net. XML error:" <<
+						xmlErrorMsg << xmlString;
+		}
+		
+		QDomNodeList contents = doc.elementsByTagName("Contents");
+		
+		QRegExp mcRegex("/minecraft.jar$");
+		QRegExp snapshotRegex("[0-9][0-9]w[0-9][0-9][a-z]?|pre|rc");
+		
+		for (int i = 0; i < contents.length(); i++)
+		{
+			QDomElement element = contents.at(i).toElement();
+			
+			if (element.isNull())
+				continue;
+			
+			QDomElement keyElement = getDomElementByTagName(element, "Key");
+			QDomElement lastmodElement = getDomElementByTagName(element, "LastModified");
+			QDomElement etagElement = getDomElementByTagName(element, "ETag");
+			
+			if (keyElement.isNull() || lastmodElement.isNull() || etagElement.isNull())
+				continue;
+			
+			QString key = keyElement.text();
+			QString lastModStr = lastmodElement.text();
+			QString etagStr = etagElement.text();
+			
+			if (!key.contains(mcRegex))
+				continue;
+			
+			QString versionDirName = key.left(key.length() - 14);
+			QString dlUrl = QString("http://assets.minecraft.net/%1/").arg(versionDirName);
+			
+			QString versionName = versionDirName.replace("_", ".");
+			
+			QDateTime versionTimestamp = timeFromS3Time(lastModStr);
+			if (!versionTimestamp.isValid())
+			{
+				qDebug(QString("Failed to parse timestamp for version %1 %2").
+					   arg(versionName, lastModStr).toUtf8());
+				versionTimestamp = QDateTime::currentDateTime();
+			}
+			
+			if (m_currentStable)
+			{
+				{
+					bool older = versionTimestamp.toMSecsSinceEpoch() < m_currentStable->timestamp();
+					bool newer = versionTimestamp.toMSecsSinceEpoch() > m_currentStable->timestamp();
+					bool isSnapshot = versionName.contains(snapshotRegex);
+					
+					MinecraftVersion *version = new MinecraftVersion(
+								versionName, versionName, 
+								versionTimestamp.toMSecsSinceEpoch(),
+								dlUrl, etagStr);
+					
+					if (newer)
+					{
+						version->setVersionType(MinecraftVersion::Snapshot);
+					}
+					else if (older && isSnapshot)
+					{
+						version->setVersionType(MinecraftVersion::OldSnapshot);
+					}
+					else if (older)
+					{
+						version->setVersionType(MinecraftVersion::Stable);
+					}
+					else
+					{
+						// Shouldn't happen, but just in case...
+						version->setVersionType(MinecraftVersion::CurrentStable);
+					}
+					
+					assetsList.push_back(version);
+				}
+			}
+			else // If there isn't a current stable version.
+			{
+				bool isSnapshot = versionName.contains(snapshotRegex);
+				
+				MinecraftVersion *version = new MinecraftVersion(
+							versionName, versionName, 
+							versionTimestamp.toMSecsSinceEpoch(),
+							dlUrl, etagStr);
+				version->setVersionType(isSnapshot? MinecraftVersion::Snapshot :
+													MinecraftVersion::Stable);
+				assetsList.push_back(version);
+			}
+		}
+		
+		setSubStatus("Loaded assets.minecraft.net");
+		succeeded = true;
+		break;
+	}
+		
+	default:
+		// TODO: Network error handling.
+		qDebug() << "Failed to load assets.minecraft.net" << assetsReply->errorString();
+		break;
+	}
+	
+	processedAssetsReply = true;
+	updateStuff();
+	return succeeded;
+}
+
+bool MCVListLoadTask::loadMCNostalgia()
+{
+	QNetworkReply *mcnReply = netMgr->get(QNetworkRequest(QUrl(QString(MCN_URLBASE) + "?pversion=1&list=True")));
+	NetUtils::waitForNetRequest(mcnReply);
+	processedMCNReply = true;
+	updateStuff();
+	return true;
+}
+
+bool MCVListLoadTask::finalize()
+{
+	// First, we need to do some cleanup. We loaded assets versions into assetsList,
+	// MCNostalgia versions into mcnList and all the others into tempList. MCNostalgia 
+	// provides some versions that are on assets.minecraft.net and we want to ignore 
+	// those, so we remove and delete them from mcnList. assets.minecraft.net also provides
+	// versions that are on Mojang's version list and we want to ignore those as well.
+	
+	// To start, we get a list of the descriptors in tmpList.
+	QStringList tlistDescriptors;
+	for (int i = 0; i < tempList.count(); i++)
+		tlistDescriptors.append(tempList.at(i)->descriptor());
+	
+	// Now, we go through our assets version list and remove anything with
+	// a descriptor that matches one we already have in tempList.
+	for (int i = 0; i < assetsList.count(); i++)
+		if (tlistDescriptors.contains(assetsList.at(i)->descriptor()))
+			delete assetsList.takeAt(i--); // We need to decrement here because we're removing an item.
+	
+	// We also need to rebuild the list of descriptors.
+	tlistDescriptors.clear();
+	for (int i = 0; i < tempList.count(); i++)
+		tlistDescriptors.append(tempList.at(i)->descriptor());
+	
+	// Next, we go through our MCNostalgia version list and do the same thing.
+	for (int i = 0; i < mcnList.count(); i++)
+		if (tlistDescriptors.contains(mcnList.at(i)->descriptor()))
+			delete mcnList.takeAt(i--); // We need to decrement here because we're removing an item.
+	
+	// Now that the duplicates are gone, we need to merge the lists. This is
+	// simple enough.
+	tempList.append(assetsList);
+	tempList.append(mcnList);
+	
+	// We're done with these lists now, but the items have been moved over to 
+	// tempList, so we don't need to delete them yet.
+	
+	// Now, we invoke the updateListData slot on the GUI thread. This will copy all
+	// the versions we loaded and set their parents to the version list.
+	// Then, it will swap the new list with the old one and free the old list's memory.
+	QMetaObject::invokeMethod(m_list, "updateListData", Qt::BlockingQueuedConnection, 
+							  Q_ARG(QList<InstVersion*>, tempList));
+	
+	// Once that's finished, we can delete the versions in our temp list.
+	while (!tempList.isEmpty())
+		delete tempList.takeFirst();
+	
+#ifdef PRINT_VERSIONS
+	m_list->printToStdOut();
+#endif
+	return true;
+}
+
+void MCVListLoadTask::updateStuff()
+{
+	const int totalReqs = 3;
+	int reqsComplete = 0;
+	
+	if (processedMCVListReply)
+		reqsComplete++;
+	if (processedAssetsReply)
+		reqsComplete++;
+	if (processedMCNReply)
+		reqsComplete++;
+	
+	calcProgress(reqsComplete, totalReqs);
+	
+	if (reqsComplete >= totalReqs)
+	{
+		quit();
+	}
+}
diff --git a/backend/lists/MinecraftVersionList.h b/backend/lists/MinecraftVersionList.h
new file mode 100644
index 00000000..10570b01
--- /dev/null
+++ b/backend/lists/MinecraftVersionList.h
@@ -0,0 +1,106 @@
+/* Copyright 2013 Andrew Okin
+ *
+ * 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 <QObject>
+
+#include <QNetworkAccessManager>
+
+#include <QList>
+
+#include "InstVersionList.h"
+
+#include "tasks/Task.h"
+
+#include "MinecraftVersion.h"
+
+#include "libmmc_config.h"
+
+class MCVListLoadTask;
+
+class LIBMULTIMC_EXPORT MinecraftVersionList : public InstVersionList
+{
+	Q_OBJECT
+public:
+	friend class MCVListLoadTask;
+	
+	explicit MinecraftVersionList(QObject *parent = 0);
+	
+	virtual Task *getLoadTask();
+	virtual bool isLoaded();
+	virtual const InstVersion *at(int i) const;
+	virtual int count() const;
+	virtual void printToStdOut() const;
+	virtual void sort();
+	
+	virtual InstVersion *getLatestStable() const;
+	
+	/*!
+	 * Gets the main version list instance.
+	 */
+	static MinecraftVersionList &getMainList();
+	
+	
+protected:
+	QList<InstVersion *>m_vlist;
+	
+	bool m_loaded;
+	
+protected slots:
+	virtual void updateListData(QList<InstVersion *> versions);
+};
+
+class MCVListLoadTask : public Task
+{
+	Q_OBJECT
+	
+public:
+	explicit MCVListLoadTask(MinecraftVersionList *vlist);
+	~MCVListLoadTask();
+	
+	virtual void executeTask();
+	
+protected:
+	void setSubStatus(const QString msg = "");
+	
+	//! Loads versions from Mojang's official version list.
+	bool loadFromVList();
+	
+	//! Loads versions from assets.minecraft.net. Any duplicates are ignored.
+	bool loadFromAssets();
+	
+	//! Loads versions from MCNostalgia.
+	bool loadMCNostalgia();
+	
+	//! Finalizes loading by updating the version list.
+	bool finalize();
+	
+	void updateStuff();
+	
+	QNetworkAccessManager *netMgr;
+	
+	MinecraftVersionList *m_list;
+	QList<InstVersion *> tempList; //! < List of loaded versions
+	QList<InstVersion *> assetsList; //! < List of versions loaded from assets.minecraft.net
+	QList<InstVersion *> mcnList; //! < List of loaded MCNostalgia versions
+	
+	MinecraftVersion *m_currentStable;
+	
+	bool processedMCVListReply;
+	bool processedAssetsReply;
+	bool processedMCNReply;
+};
+
diff --git a/backend/tasks/GameUpdateTask.cpp b/backend/tasks/GameUpdateTask.cpp
new file mode 100644
index 00000000..0a1df0e1
--- /dev/null
+++ b/backend/tasks/GameUpdateTask.cpp
@@ -0,0 +1,283 @@
+/* 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 "GameUpdateTask.h"
+
+#include <QtNetwork>
+
+#include <QFile>
+#include <QFileInfo>
+#include <QTextStream>
+#include <QDataStream>
+
+#include <QDebug>
+
+#include "lists/MinecraftVersionList.h"
+#include "VersionFactory.h"
+#include "OneSixVersion.h"
+
+#include "pathutils.h"
+
+
+GameUpdateTask::GameUpdateTask(const LoginResponse &response, BaseInstance *inst, QObject *parent) :
+	Task(parent), m_response(response)
+{
+	m_inst = inst;
+	m_updateState = StateInit;
+}
+
+void GameUpdateTask::executeTask()
+{
+	updateStatus();
+	
+	// Get a pointer to the version object that corresponds to the instance's version.
+	targetVersion = (MinecraftVersion *)MinecraftVersionList::getMainList().
+			findVersion(m_inst->intendedVersion());
+	if(targetVersion == NULL)
+	{
+		//Q_ASSERT_X(targetVersion != NULL, "game update", "instance's intended version is not an actual version");
+		setState(StateFinished);
+		emit gameUpdateComplete(m_response);
+		return;
+	}
+	
+	/////////////////////////
+	// BUILD DOWNLOAD LIST //
+	/////////////////////////
+	// Build a list of URLs that will need to be downloaded.
+	
+	setState(StateDetermineURLs);
+	
+	if (targetVersion->versionSource() == MinecraftVersion::Launcher16)
+	{
+		determineNewVersion();
+	}
+	else
+	{
+		getLegacyJar();
+	}
+	QEventLoop loop;
+	loop.exec();
+}
+
+void GameUpdateTask::determineNewVersion()
+{
+	QString urlstr("http://s3.amazonaws.com/Minecraft.Download/versions/");
+	urlstr += targetVersion->descriptor() + "/" + targetVersion->descriptor() + ".json";
+	auto dljob = DownloadJob::create(QUrl(urlstr));
+	specificVersionDownloadJob.reset(new JobList());
+	specificVersionDownloadJob->add(dljob);
+	connect(specificVersionDownloadJob.data(), SIGNAL(finished()), SLOT(versionFileFinished()));
+	connect(specificVersionDownloadJob.data(), SIGNAL(failed()), SLOT(versionFileFailed()));
+	connect(specificVersionDownloadJob.data(), SIGNAL(progress(qint64,qint64)), SLOT(updateDownloadProgress(qint64,qint64)));
+	download_queue.enqueue(specificVersionDownloadJob);
+}
+
+void GameUpdateTask::versionFileFinished()
+{
+	JobPtr firstJob = specificVersionDownloadJob->getFirstJob();
+	auto DlJob = firstJob.dynamicCast<DownloadJob>();
+	FullVersionFactory parser;
+	auto version = parser.parse(DlJob->m_data);
+	
+	if(!version)
+	{
+		error(parser.error_string);
+		exit(0);
+	}
+	
+	if(version->isLegacy)
+	{
+		getLegacyJar();
+		return;
+	}
+	
+	// save the version file in $instanceId/version.json and versions/$version/$version.json
+	QString version_id = targetVersion->descriptor();
+	QString mc_dir = m_inst->minecraftDir();
+	QString inst_dir = m_inst->rootDir();
+	QString version1 =  PathCombine(inst_dir, "/version.json");
+	QString version2 =  QString("versions/") + version_id + "/" + version_id + ".json";
+	DownloadJob::ensurePathExists(version1);
+	DownloadJob::ensurePathExists(version2);
+	QFile  vfile1 (version1);
+	QFile  vfile2 (version2);
+	vfile1.open(QIODevice::Truncate | QIODevice::WriteOnly );
+	vfile2.open(QIODevice::Truncate | QIODevice::WriteOnly );
+	vfile1.write(DlJob->m_data);
+	vfile2.write(DlJob->m_data);
+	vfile1.close();
+	vfile2.close();
+	
+	// download the right jar, save it in versions/$version/$version.jar
+	QString urlstr("http://s3.amazonaws.com/Minecraft.Download/versions/");
+	urlstr += targetVersion->descriptor() + "/" + targetVersion->descriptor() + ".jar";
+	QString targetstr ("versions/");
+	targetstr += targetVersion->descriptor() + "/" + targetVersion->descriptor() + ".jar";
+	auto dljob = DownloadJob::create(QUrl(urlstr), targetstr);
+	
+	jarlibDownloadJob.reset(new JobList());
+	jarlibDownloadJob->add(dljob);
+	connect(jarlibDownloadJob.data(), SIGNAL(finished()), SLOT(jarlibFinished()));
+	connect(jarlibDownloadJob.data(), SIGNAL(failed()), SLOT(jarlibFailed()));
+	connect(jarlibDownloadJob.data(), SIGNAL(progress(qint64,qint64)), SLOT(updateDownloadProgress(qint64,qint64)));
+	// determine and download all the libraries, save them in libraries/whatever...
+	download_queue.enqueue(jarlibDownloadJob);
+}
+
+void GameUpdateTask::jarlibFinished()
+{
+	m_inst->setCurrentVersion(targetVersion->descriptor());
+	m_inst->setShouldUpdate(false);
+	// m_inst->setIsForNewLauncher(true);
+	exit(1);
+}
+
+void GameUpdateTask::jarlibFailed()
+{
+	error("Failed to download the binary garbage. Try again. Maybe. IF YOU DARE");
+	exit(0);
+}
+
+void GameUpdateTask::versionFileFailed()
+{
+	error("Failed to download the version description. Try again.");
+	exit(0);
+}
+
+
+// this is legacy minecraft...
+void GameUpdateTask::getLegacyJar()
+{
+	// Make directories
+	QDir binDir(m_inst->binDir());
+	if (!binDir.exists() && !binDir.mkpath("."))
+	{
+		error("Failed to create bin folder.");
+		return;
+	}
+	
+	// Add the URL for minecraft.jar
+	// This will be either 'minecraft' or the version number, depending on where
+	// we're downloading from.
+	QString jarFilename = "minecraft";
+	if (targetVersion->versionSource() == MinecraftVersion::Launcher16)
+	{
+		jarFilename = targetVersion->descriptor();
+	}
+	
+	QUrl mcJarURL = targetVersion->downloadURL() + jarFilename + ".jar";
+	qDebug() << mcJarURL.toString();
+	auto dljob = DownloadJob::create(mcJarURL, PathCombine(m_inst->minecraftDir(), "bin/minecraft.jar"));
+	
+	legacyDownloadJob.reset(new JobList());
+	legacyDownloadJob->add(dljob);
+	connect(legacyDownloadJob.data(), SIGNAL(finished()), SLOT(legacyJarFinished()));
+	connect(legacyDownloadJob.data(), SIGNAL(failed()), SLOT(legacyJarFailed()));
+	connect(legacyDownloadJob.data(), SIGNAL(progress(qint64,qint64)), SLOT(updateDownloadProgress(qint64,qint64)));
+	
+	download_queue.enqueue(legacyDownloadJob);
+}
+
+
+void GameUpdateTask::legacyJarFinished()
+{
+	setState(StateFinished);
+	emit gameUpdateComplete(m_response);
+	// m_inst->setIsForNewLauncher(true);
+	exit(1);
+}
+
+void GameUpdateTask::legacyJarFailed()
+{
+	emit gameUpdateError("failed to download the minecraft.jar");
+	exit(0);
+}
+
+int GameUpdateTask::state() const
+{
+	return m_updateState;
+}
+
+void GameUpdateTask::setState(int state, bool resetSubStatus)
+{
+	m_updateState = state;
+	if (resetSubStatus)
+		setSubStatus("");
+	else // We only need to update if we're not resetting substatus becasue setSubStatus updates status for us.
+		updateStatus();
+}
+
+QString GameUpdateTask::subStatus() const
+{
+	return m_subStatusMsg;
+}
+
+void GameUpdateTask::setSubStatus(const QString &msg)
+{
+	m_subStatusMsg = msg;
+	updateStatus();
+}
+
+QString GameUpdateTask::getStateMessage(int state)
+{
+	switch (state)
+	{
+	case StateInit:
+		return "Initializing";
+		
+	case StateDetermineURLs:
+		return "Determining files to download";
+		
+	case StateDownloadFiles:
+		return "Downloading files";
+		
+	case StateInstall:
+		return "Installing";
+		
+	case StateFinished:
+		return "Finished";
+	
+	default:
+		return "Downloading instance files";
+	}
+}
+
+void GameUpdateTask::updateStatus()
+{
+	QString newStatus;
+	
+	newStatus = getStateMessage(state());
+	if (!subStatus().isEmpty())
+		newStatus += ": " + subStatus();
+	else
+		newStatus += "...";
+	
+	setStatus(newStatus);
+}
+
+
+void GameUpdateTask::error(const QString &msg)
+{
+	emit gameUpdateError(msg);
+}
+
+void GameUpdateTask::updateDownloadProgress(qint64 current, qint64 total)
+{
+	// The progress on the current file is current / total
+	float currentDLProgress = (float) current / (float) total;
+	setProgress((int)(currentDLProgress * 100)); // convert to percentage
+}
+
diff --git a/backend/tasks/GameUpdateTask.h b/backend/tasks/GameUpdateTask.h
new file mode 100644
index 00000000..94e798f1
--- /dev/null
+++ b/backend/tasks/GameUpdateTask.h
@@ -0,0 +1,157 @@
+/* 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 <QObject>
+
+#include <QList>
+
+#include <QNetworkAccessManager>
+#include <QUrl>
+#include "dlqueue.h"
+
+#include "Task.h"
+#include "tasks/LoginResponse.h"
+#include "BaseInstance.h"
+
+#include "libmmc_config.h"
+
+class MinecraftVersion;
+
+/*!
+ * The game update task is the task that handles downloading instances' files.
+ */
+class LIBMULTIMC_EXPORT GameUpdateTask : public Task
+{
+	Q_OBJECT
+	
+	/*!
+	 * The task's state.
+	 * A certain state message will be shown depending on what this is set to.
+	 */
+	Q_PROPERTY(int state READ state WRITE setState)
+	
+	/*!
+	 * The substatus message.
+	 * This will be next to the the state message in the task's status.
+	 */
+	Q_PROPERTY(QString subStatus READ subStatus WRITE setSubStatus)
+public:
+	explicit GameUpdateTask(const LoginResponse &response, BaseInstance *inst, QObject *parent = 0);
+	
+	
+	/////////////////////////
+	// EXECUTION FUNCTIONS //
+	/////////////////////////
+	
+	virtual void executeTask();
+	
+	//////////////////////
+	// STATE AND STATUS //
+	//////////////////////
+	
+	virtual int state() const;
+	virtual void setState(int state, bool resetSubStatus = true);
+	
+	virtual QString subStatus() const;
+	virtual void setSubStatus(const QString &msg);
+	
+	/*!
+	 * Gets the message that will be displated for the given state.
+	 */
+	virtual QString getStateMessage(int state);
+	
+private:
+	void getLegacyJar();
+	void determineNewVersion();
+	
+public slots:
+	
+	/*!
+	 * Updates the status message based on the state and substatus message.
+	 */
+	virtual void updateStatus();
+	
+	
+	virtual void error(const QString &msg);
+	
+	
+private slots:
+	void updateDownloadProgress(qint64 current, qint64 total);
+	void legacyJarFinished();
+	void legacyJarFailed();
+	
+	void versionFileFinished();
+	void versionFileFailed();
+	
+	void jarlibFinished();
+	void jarlibFailed();
+	
+signals:
+	/*!
+	 * \brief Signal emitted when the game update is complete.
+	 * \param response The login response received from login task.
+	 */
+	void gameUpdateComplete(const LoginResponse &response);
+	
+	/*!
+	 * \brief Signal emitted if an error occurrs during the update.
+	 * \param errorMsg An error message to be displayed to the user.
+	 */
+	void gameUpdateError(const QString &errorMsg);
+	
+private:
+	///////////
+	// STUFF //
+	///////////
+	
+	BaseInstance *m_inst;
+	LoginResponse m_response;
+	
+	////////////////////////////
+	// STATE AND STATUS STUFF //
+	////////////////////////////
+	
+	int m_updateState;
+	QString m_subStatusMsg;
+	
+	enum UpdateState
+	{
+		// Initializing
+		StateInit = 0,
+		
+		// Determining files to download
+		StateDetermineURLs,
+		
+		// Downloading files
+		StateDownloadFiles,
+		
+		// Installing files
+		StateInstall,
+		
+		// Finished
+		StateFinished
+	};
+	JobListPtr legacyDownloadJob;
+	JobListPtr specificVersionDownloadJob;
+	JobListPtr jarlibDownloadJob;
+	JobListQueue download_queue;
+	
+	// target version, determined during this task
+	MinecraftVersion *targetVersion;
+};
+
+
diff --git a/backend/tasks/LoginResponse.cpp b/backend/tasks/LoginResponse.cpp
new file mode 100644
index 00000000..218f51c1
--- /dev/null
+++ b/backend/tasks/LoginResponse.cpp
@@ -0,0 +1,69 @@
+/* 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 "tasks/LoginResponse.h"
+
+LoginResponse::LoginResponse(const QString& username, const QString& sessionID, 
+							 qint64 latestVersion, QObject *parent) :
+	QObject(parent)
+{
+	this->m_username = username;
+	this->m_sessionID = sessionID;
+	this->m_latestVersion = latestVersion;
+}
+
+LoginResponse::LoginResponse()
+{
+	this->m_username = "";
+	this->m_sessionID = "";
+	this->m_latestVersion = 0;
+}
+
+LoginResponse::LoginResponse(const LoginResponse &other)
+{
+	this->m_username = other.username();
+	this->m_sessionID = other.sessionID();
+	this->m_latestVersion = other.latestVersion();
+}
+
+QString LoginResponse::username() const
+{
+	return m_username;
+}
+
+void LoginResponse::setUsername(const QString& username)
+{
+	this->m_username = username;
+}
+
+QString LoginResponse::sessionID() const
+{
+	return m_sessionID;
+}
+
+void LoginResponse::setSessionID(const QString& sessionID)
+{
+	this->m_sessionID = sessionID;
+}
+
+qint64 LoginResponse::latestVersion() const
+{
+	return m_latestVersion;
+}
+
+void LoginResponse::setLatestVersion(qint64 v)
+{
+	this->m_latestVersion = v;
+}
diff --git a/backend/tasks/LoginResponse.h b/backend/tasks/LoginResponse.h
new file mode 100644
index 00000000..60875619
--- /dev/null
+++ b/backend/tasks/LoginResponse.h
@@ -0,0 +1,94 @@
+/* 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 <QObject>
+
+#include "libmmc_config.h"
+
+/*!
+ * \brief The LoginResponse class represents a response received from Minecraft's login servers.
+ */
+class LIBMULTIMC_EXPORT LoginResponse : public QObject
+{
+	Q_OBJECT
+public:
+	/*!
+	 * \brief Creates a new instance of the LoginResponse class.
+	 * \param username The user's username.
+	 * \param sessionID The user's session ID.
+	 * \param latestVersion The latest version of Minecraft.
+	 * \param parent The parent object.
+	 */
+	explicit LoginResponse(const QString &username, const QString &sessionID, 
+						   qint64 latestVersion, QObject *parent = 0);
+	LoginResponse();
+	LoginResponse(const LoginResponse& other);
+	
+	/*!
+	 * \brief Gets the username.
+	 * This one should go without saying.
+	 * \return The username.
+	 * \sa setUsername()
+	 */
+	QString username() const;
+	
+	/*!
+	 * \brief setUsername Sets the username.
+	 * \param username The new username.
+	 * \sa username()
+	 */
+	void setUsername(const QString& username);
+	
+	
+	/*!
+	 * \brief Gets the session ID.
+	 * \return The session ID.
+	 * \sa setSessionID()
+	 */
+	QString sessionID() const;
+	
+	/*!
+	 * \brief Sets the session ID.
+	 * \param sessionID The new session ID.
+	 * \sa sessionID()
+	 */
+	void setSessionID(const QString& sessionID);
+	
+	
+	/*!
+	 * \brief Gets the latest version.
+	 * This is a value returned by the login servers when a user logs in.
+	 * \return The latest version.
+	 * \sa setLatestVersion()
+	 */
+	qint64 latestVersion() const;
+	
+	/*!
+	 * \brief Sets the latest version.
+	 * \param v The new latest version.
+	 * \sa latestVersion()
+	 */
+	void setLatestVersion(qint64 v);
+	
+private:
+	QString m_username;
+	QString m_sessionID;
+	qint64 m_latestVersion;
+};
+
+Q_DECLARE_METATYPE(LoginResponse)
+
diff --git a/backend/tasks/LoginTask.cpp b/backend/tasks/LoginTask.cpp
new file mode 100644
index 00000000..11f58f28
--- /dev/null
+++ b/backend/tasks/LoginTask.cpp
@@ -0,0 +1,121 @@
+/* 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 "LoginTask.h"
+
+#include <QStringList>
+
+#include <QtNetwork/QNetworkAccessManager>
+#include <QtNetwork/QNetworkReply>
+#include <QtNetwork/QNetworkRequest>
+
+#include <QUrl>
+#include <QUrlQuery>
+
+LoginTask::LoginTask( const UserInfo& uInfo, QObject* parent ) :
+	Task(parent), uInfo(uInfo)
+{
+	
+}
+
+void LoginTask::executeTask()
+{
+	setStatus("Logging in...");
+	
+	QNetworkAccessManager netMgr;
+	connect(&netMgr, SIGNAL(finished(QNetworkReply*)),
+			SLOT(processNetReply(QNetworkReply*)));
+	
+	QUrl loginURL("https://login.minecraft.net/");
+	QNetworkRequest netRequest(loginURL);
+	netRequest.setHeader(QNetworkRequest::ContentTypeHeader, 
+						 "application/x-www-form-urlencoded");
+	
+	QUrlQuery params;
+	params.addQueryItem("user", uInfo.username());
+	params.addQueryItem("password", uInfo.password());
+	params.addQueryItem("version", "13");
+	
+	netReply = netMgr.post(netRequest, params.query(QUrl::EncodeSpaces).toUtf8());
+	exec();
+}
+
+void LoginTask::processNetReply(QNetworkReply *reply)
+{
+	// Check for errors.
+	switch (reply->error())
+	{
+	case QNetworkReply::NoError:
+	{
+		// Check the response code.
+		int responseCode = reply->attribute(QNetworkRequest::HttpStatusCodeAttribute).toInt();
+		
+		if (responseCode == 200)
+		{
+			QString responseStr(reply->readAll());
+			
+			QStringList strings = responseStr.split(":");
+			if (strings.count() >= 4)
+			{
+				bool parseSuccess;
+				qint64 latestVersion = strings[0].toLongLong(&parseSuccess);
+				if (parseSuccess)
+				{
+					// strings[1] is the download ticket. It isn't used anymore.
+					QString username = strings[2];
+					QString sessionID = strings[3];
+					
+					LoginResponse response(username, sessionID, latestVersion);
+					emit loginComplete(response);
+				}
+				else
+				{
+					emit loginFailed("Failed to parse Minecraft version string.");
+				}
+			}
+			else
+			{
+				if (responseStr.toLower() == "bad login")
+					emit loginFailed("Invalid username or password.");
+				else if (responseStr.toLower() == "old version")
+					emit loginFailed("Launcher outdated, please update.");
+				else
+					emit loginFailed("Login failed: " + responseStr);
+			}
+		}
+		else if (responseCode == 503)
+		{
+			emit loginFailed("The login servers are currently unavailable. "
+							 "Check http://help.mojang.com/ for more info.");
+		}
+		else
+		{
+			emit loginFailed(QString("Login failed: Unknown HTTP error %1 occurred.").
+							 arg(QString::number(responseCode)));
+		}
+		break;
+	}
+		
+	case QNetworkReply::OperationCanceledError:
+		emit loginFailed("Login canceled.");
+		break;
+		
+	default:
+		emit loginFailed("Login failed: " + reply->errorString());
+		break;
+	}
+	
+	quit();
+}
diff --git a/backend/tasks/LoginTask.h b/backend/tasks/LoginTask.h
new file mode 100644
index 00000000..e23ea9e9
--- /dev/null
+++ b/backend/tasks/LoginTask.h
@@ -0,0 +1,49 @@
+/* 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.
+ */
+
+#ifndef LOGINTASK_H
+#define LOGINTASK_H
+
+#include "Task.h"
+
+#include "UserInfo.h"
+#include "tasks/LoginResponse.h"
+
+#include "libmmc_config.h"
+
+//class QNetworkAccessManager;
+class QNetworkReply;
+
+class LIBMULTIMC_EXPORT LoginTask : public Task
+{
+	Q_OBJECT
+public:
+	explicit LoginTask(const UserInfo& uInfo, QObject *parent = 0);
+	
+public slots:
+	void processNetReply(QNetworkReply* reply);
+	
+signals:
+	void loginComplete(LoginResponse loginResponse);
+	void loginFailed(const QString& errorMsg);
+	
+protected:
+	void executeTask();
+	
+	QNetworkReply* netReply;
+	UserInfo uInfo;
+};
+
+#endif // LOGINTASK_H
diff --git a/backend/tasks/Task.cpp b/backend/tasks/Task.cpp
new file mode 100644
index 00000000..7831ee58
--- /dev/null
+++ b/backend/tasks/Task.cpp
@@ -0,0 +1,83 @@
+/* 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 "Task.h"
+
+Task::Task(QObject *parent) :
+	QThread(parent)
+{
+	
+}
+
+QString Task::getStatus() const
+{
+	return status;
+}
+
+void Task::setStatus(const QString &status)
+{
+	this->status = status;
+	emitStatusChange(status);
+}
+
+int Task::getProgress() const
+{
+	return progress;
+}
+
+void Task::calcProgress(int parts, int whole)
+{
+	setProgress((int)((((float)parts) / ((float)whole))*100)); // Not sure if C++ or LISP...
+}
+
+void Task::setProgress(int progress)
+{
+	this->progress = progress;
+	emitProgressChange(progress);
+}
+
+void Task::startTask()
+{
+	start();
+}
+
+void Task::run()
+{
+	emitStarted();
+	executeTask();
+	emitEnded();
+}
+
+void Task::emitStarted()
+{
+	emit started();
+	emit started(this);
+}
+
+void Task::emitEnded()
+{
+	emit ended();
+	emit ended(this);
+}
+
+void Task::emitStatusChange(const QString &status)
+{
+	emit statusChanged(status);
+}
+
+void Task::emitProgressChange(int progress)
+{
+	emit progressChanged(progress);
+}
diff --git a/backend/tasks/Task.h b/backend/tasks/Task.h
new file mode 100644
index 00000000..c8c12c02
--- /dev/null
+++ b/backend/tasks/Task.h
@@ -0,0 +1,78 @@
+/* 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.
+ */
+
+#ifndef TASK_H
+#define TASK_H
+
+#include <QObject>
+#include <QThread>
+#include <QString>
+
+#include "libmmc_config.h"
+
+class LIBMULTIMC_EXPORT Task : public QThread
+{
+	Q_OBJECT
+public:
+	explicit Task(QObject *parent = 0);
+	
+	// Starts the task.
+	void startTask();
+	
+	QString getStatus() const;
+	int getProgress() const;
+	
+	/*!
+	 * \brief Calculates and sets the task's progress based on the number of parts completed out of the total number to complete.
+	 * This is essentially just shorthand for setProgress((parts / whole) * 100);
+	 * \param parts The parts out of the whole completed. This parameter should
+	 * be less than whole. If it is greater than whole, progress is set to 100.
+	 * \param whole The total number of things that need to be completed.
+	 */
+	void calcProgress(int parts, int whole);
+	
+public slots:
+	void setStatus(const QString& status);
+	void setProgress(int progress);
+	
+signals:
+	void started(Task* task);
+	void ended(Task* task);
+	
+	void started();
+	void ended();
+	
+	
+	void statusChanged(Task* task, const QString& status);
+	void progressChanged(Task* task, int progress);
+	
+	void statusChanged(const QString& status);
+	void progressChanged(int progress);
+	
+protected:
+	virtual void run();
+	virtual void executeTask() = 0;
+	
+	virtual void emitStarted();
+	virtual void emitEnded();
+	
+	virtual void emitStatusChange(const QString &status);
+	virtual void emitProgressChange(int progress);
+	
+	QString status;
+	int progress;
+};
+
+#endif // TASK_H
diff --git a/backend/tasks/UserInfo.cpp b/backend/tasks/UserInfo.cpp
new file mode 100644
index 00000000..82225309
--- /dev/null
+++ b/backend/tasks/UserInfo.cpp
@@ -0,0 +1,49 @@
+/* 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 "UserInfo.h"
+
+UserInfo::UserInfo(const QString &username, const QString &password, QObject *parent) :
+	QObject(parent)
+{
+	this->m_username = username;
+	this->m_password = password;
+}
+
+UserInfo::UserInfo(const UserInfo &other)
+{
+	this->m_username = other.m_username;
+	this->m_password = other.m_password;
+}
+
+QString UserInfo::username() const
+{
+	return m_username;
+}
+
+void UserInfo::setUsername(const QString &username)
+{
+	this->m_username = username;
+}
+
+QString UserInfo::password() const
+{
+	return m_password;
+}
+
+void UserInfo::setPassword(const QString &password)
+{
+	this->m_password = password;
+}
diff --git a/backend/tasks/UserInfo.h b/backend/tasks/UserInfo.h
new file mode 100644
index 00000000..280f98de
--- /dev/null
+++ b/backend/tasks/UserInfo.h
@@ -0,0 +1,41 @@
+/* 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.
+ */
+
+#ifndef USERINFO_H
+#define USERINFO_H
+
+#include <QObject>
+
+#include "libmmc_config.h"
+
+class LIBMULTIMC_EXPORT UserInfo : public QObject
+{
+	Q_OBJECT
+public:
+	explicit UserInfo(const QString& username, const QString& password, QObject *parent = 0);
+	explicit UserInfo(const UserInfo& other);
+	
+	QString username() const;
+	void setUsername(const QString& username);
+	
+	QString password() const;
+	void setPassword(const QString& password);
+	
+protected:
+	QString m_username;
+	QString m_password;
+};
+
+#endif // USERINFO_H