Split MultiMC up into a few separate libraries.

Fixed plugin system.

Tons of other stuff...

7 files changed, 749 insertions, 0 deletions

diff --git a/libinstance/include/instance.h b/libinstance/include/instance.h
new file mode 100644
index 00000000..7b3c001d
--- /dev/null
+++ b/libinstance/include/instance.h
@@ -0,0 +1,342 @@
+/* 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 INSTANCE_H
+#define INSTANCE_H
+
+#include <QObject>
+#include <QDateTime>
+
+#include "appsettings.h"
+#include "inifile.h"
+
+#include "libinstance_config.h"
+
+#define DEFINE_OVERRIDDEN_SETTING_ADVANCED(funcName, cfgEntryName, typeName) \
+	typeName get ## funcName() const { return getField(cfgEntryName, settings->get ## funcName()).value<typeName>(); }
+
+#define DEFINE_OVERRIDDEN_SETTING(funcName, typeName) \
+	DEFINE_OVERRIDDEN_SETTING_ADVANCED(funcName, STR_VAL(funcName), typeName)
+
+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 LIBMMCINST_EXPORT Instance : public SettingsBase
+{
+	Q_OBJECT
+public:
+	explicit Instance(const QString &rootDir, QObject *parent = 0);
+	
+	// Please, for the sake of my (and everyone else's) sanity, at least keep this shit
+	// *somewhat* organized. Also, documentation is semi-important here. Please don't
+	// leave undocumented stuff behind.
+	
+	
+	//////// STUFF ////////
+	
+	/*!
+	 * \brief Get 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.
+	 * 
+	 * \return The instance's ID.
+	 */
+	virtual QString id() const;
+	
+	/*!
+	 * \brief Gets the path to the instance's root directory.
+	 * \return  The path to the instance's root directory.
+	 */
+	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;
+	
+	
+	//////// FIELDS AND SETTINGS ////////
+	// Fields are options stored in the instance's config file that are specific
+	// to instances (not a part of SettingsBase). Settings are things overridden
+	// from SettingsBase.
+	
+	
+	////// Fields //////
+	
+	//// General Info ////
+	
+	/*!
+	 * \brief Gets this instance's name.
+	 *        This is the name that will be displayed to the user.
+	 * \return The instance's name.
+	 * \sa setName
+	 */
+	virtual QString name() { return getField("name", "Unnamed Instance").value<QString>(); }
+	
+	/*!
+	 * \brief Sets the instance's name
+	 * \param val The instance's new name.
+	 */
+	virtual void setName(QString val) { setField("name", val); }
+	
+	/*!
+	 * \brief Gets the instance's icon key.
+	 * \return The instance's icon key.
+	 * \sa setIconKey()
+	 */
+	virtual QString iconKey() const { return getField("iconKey", "default").value<QString>(); }
+	
+	/*!
+	 * \brief Sets the instance's icon key.
+	 * \param val The new icon key.
+	 */
+	virtual void setIconKey(QString val) { setField("iconKey", val); }
+	
+	
+	/*!
+	 * \brief Gets the instance's notes.
+	 * \return The instances notes.
+	 */
+	virtual QString notes() const { return getField("notes", "").value<QString>(); }
+	
+	/*!
+	 * \brief Sets the instance's notes.
+	 * \param val The instance's new notes.
+	 */
+	virtual void setNotes(QString val) { setField("notes", val); }
+	
+	
+	/*!
+	 * \brief Checks if	the instance's minecraft.jar needs to be rebuilt.
+	 *        If this is true, the instance's mods will be reinstalled to its
+	 *        minecraft.jar file. This value is automatically set to true when
+	 *        the jar mod list changes.
+	 * \return Whether or not the instance's jar file should be rebuilt.
+	 */
+	virtual bool shouldRebuild() const { return getField("NeedsRebuild", false).value<bool>(); }
+	
+	/*!
+	 * \brief Sets whether or not the instance's minecraft.jar needs to be rebuilt.
+	 * \param val Whether the instance's minecraft needs to be rebuilt or not.
+	 */
+	virtual void setShouldRebuild(bool val) { setField("NeedsRebuild", val); }
+	
+	
+	//// Version Stuff ////
+	
+	/*!
+	 * \brief Sets the instance's current version.
+	 *        This value represents the instance's current version. If this value
+	 *        is different from intendedVersion(), the instance should be updated.
+	 *        This value is updated by the updateCurrentVersion() function.
+	 * \return A string representing the instance's current version.
+	 */
+	virtual QString currentVersion() { return getField("JarVersion", "Unknown").value<QString>(); }
+	
+	/*!
+	 * \brief Sets the instance's current version.
+	 *        This is used to keep track of the instance's current version. Don't
+	 *        mess with this unless you know what you're doing.
+	 * \param val The new value.
+	 */
+	virtual void setCurrentVersion(QString val) { setField("JarVersion", val); }
+	
+	
+	/*!
+	 * \brief Gets the version of LWJGL that this instance should use.
+	 *        If no LWJGL version is specified in the instance's config file, 
+	 *        defaults to "Mojang"
+	 * \return The instance's LWJGL version.
+	 */
+	virtual QString lwjglVersion() { return getField("LwjglVersion", "Mojang").value<QString>(); }
+	
+	/*!
+	 * \brief Sets the version of LWJGL that this instance should use.
+	 * \param val The LWJGL version to use
+	 */
+	virtual void setLWJGLVersion(QString val) { setField("LwjglVersion", val); }
+	
+	
+	/*!
+	 * \brief Gets the version that this instance should try to update to.
+	 *        If this value differs from currentVersion(), the instance will
+	 *        download the intended version when it launches.
+	 * \return The instance's intended version.
+	 */
+	virtual QString intendedVersion() { return getField("IntendedJarVersion", currentVersion()).value<QString>(); }
+	
+	/*!
+	 * \brief Sets the version that this instance should try to update to.
+	 * \param val The instance's new intended version.
+	 */
+	virtual void setIntendedVersion(QString val) { setField("IntendedJarVersion", val); }
+	
+	
+	
+	//// Timestamps ////
+	
+	/*!
+	 * \brief Gets the time that the instance was last launched.
+	 *        Measured in milliseconds since epoch. QDateTime::currentMSecsSinceEpoch()
+	 * \return The time that the instance was last launched.
+	 */
+	virtual qint64 lastLaunch() { return getField("lastLaunchTime", 0).value<qint64>(); }
+	
+	/*!
+	 * \brief Sets the time that the instance was last launched.
+	 * \param val The time to set. Defaults to QDateTime::currentMSecsSinceEpoch()
+	 */
+	virtual void setLastLaunch(qint64 val = QDateTime::currentMSecsSinceEpoch()) 
+	{ setField("lastLaunchTime", val); }
+	
+	
+	////// Directories //////
+	//! Gets the path to the instance's minecraft folder.
+	QString minecraftDir() const;
+	
+	/*!
+	 * \brief Gets the path to the instance's instance mods folder.
+	 * This is the folder where the jar mods are kept.
+	 */
+	QString instModsDir() const;
+	
+	//! Gets the path to the instance's bin folder.
+	QString binDir() const;
+	
+	//! Gets the path to the instance's saves folder.
+	QString savesDir() const;
+	
+	//! Gets the path to the instance's mods folder. (.minecraft/mods)
+	QString mlModsDir() const;
+	
+	//! Gets the path to the instance's coremods folder.
+	QString coreModsDir() const;
+	
+	//! Gets the path to the instance's resources folder.
+	QString resourceDir() const;
+	
+	//! Gets the path to the instance's screenshots folder.
+	QString screenshotsDir() const;
+	
+	//! Gets the path to the instance's texture packs folder.
+	QString texturePacksDir() const;
+	
+	
+	////// Files //////
+	//! Gets the path to the instance's minecraft.jar
+	QString mcJar() const;
+	
+	//! Gets the path to the instance's mcbackup.jar.
+	QString mcBackup() const;
+	
+	//! Gets the path to the instance's config file.
+	QString configFile() const;
+	
+	//! Gets the path to the instance's modlist file.
+	QString modListFile() const;
+	
+	////// Settings //////
+	
+	//// Java Settings ////
+	DEFINE_OVERRIDDEN_SETTING_ADVANCED(JavaPath, JPATHKEY, QString)
+	DEFINE_OVERRIDDEN_SETTING(JvmArgs, QString)
+	
+	//// Custom Commands ////
+	DEFINE_OVERRIDDEN_SETTING(PreLaunchCommand, QString)
+	DEFINE_OVERRIDDEN_SETTING(PostExitCommand, QString)
+	
+	//// Memory ////
+	DEFINE_OVERRIDDEN_SETTING(MinMemAlloc, int)
+	DEFINE_OVERRIDDEN_SETTING(MaxMemAlloc, int)
+	
+	//// Auto login ////
+	DEFINE_OVERRIDDEN_SETTING(AutoLogin, bool)
+	
+	// This little guy here is to keep Qt Creator from being a dumbass and 
+	// auto-indenting the lines below the macros. Seriously, it's really annoying.
+	;
+	
+	
+	//////// 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() = 0;
+	
+	/*!
+	 * \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) = 0; 
+	
+protected:
+	/*!
+	 * \brief Gets the value of the given field in the instance's config file.
+	 *        If the value isn't in the config file, defVal is returned instead.
+	 * \param name The name of the field in the config file.
+	 * \param defVal The default value.
+	 * \return The value of the given field or defVal if the field doesn't exist.
+	 * \sa setField()
+	 */
+	virtual QVariant getField(const QString &name, QVariant defVal = QVariant()) const;
+	
+	/*!
+	 * \brief Sets the value of the given field in the config file.
+	 * \param name The name of the field in the config file.
+	 * \param val The value to set the field to.
+	 * \sa getField()
+	 */
+	virtual void setField(const QString &name, QVariant val);
+	
+	// Overrides for SettingBase stuff.
+	virtual QVariant getValue(const QString &name, QVariant defVal = QVariant()) const
+	{ return settings->getValue(name, defVal); }
+	virtual void setValue(const QString &name, QVariant val)
+	{ setField(name, val); }
+	
+	INIFile config;
+	
+private:
+	QString m_rootDir;
+};
+
+#endif // INSTANCE_H
diff --git a/libinstance/include/instancelist.h b/libinstance/include/instancelist.h
new file mode 100644
index 00000000..f6be815c
--- /dev/null
+++ b/libinstance/include/instancelist.h
@@ -0,0 +1,59 @@
+/* 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 INSTANCELIST_H
+#define INSTANCELIST_H
+
+#include <QObject>
+
+#include <QSharedPointer>
+
+#include "siglist.h"
+
+#include "libinstance_config.h"
+
+class Instance;
+
+class LIBMMCINST_EXPORT InstanceList : public QObject, public SigList<QSharedPointer<Instance>>
+{
+	Q_OBJECT
+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.
+	 */
+	InstListError loadList();
+	
+	DEFINE_SIGLIST_SIGNALS(QSharedPointer<Instance>);
+	SETUP_SIGLIST_SIGNALS(QSharedPointer<Instance>);
+protected:
+	QString m_instDir;
+};
+
+#endif // INSTANCELIST_H
diff --git a/libinstance/include/instanceloader.h b/libinstance/include/instanceloader.h
new file mode 100644
index 00000000..39696639
--- /dev/null
+++ b/libinstance/include/instanceloader.h
@@ -0,0 +1,137 @@
+/* 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 INSTANCELOADER_H
+#define INSTANCELOADER_H
+
+#include <QObject>
+#include <QMap>
+#include <QList>
+
+#include "libinstance_config.h"
+
+class InstanceTypeInterface;
+class Instance;
+
+typedef QList<const InstanceTypeInterface *> InstTypeList;
+
+/*!
+ * \brief The InstanceLoader is a singleton that manages all of the instance types and handles loading and creating instances.
+ * Instance types are registered with the instance loader through its registerInstType() function. 
+ * Creating instances is done through the InstanceLoader's createInstance() function. This function takes 
+ */
+class LIBMMCINST_EXPORT InstanceLoader : public QObject
+{
+	Q_OBJECT
+public:
+	/*!
+	 * \brief Gets a reference to the instance loader.
+	 */
+	static InstanceLoader &get() { return loader; }
+	
+	/*!
+	 * \brief Error codes returned by functions in the InstanceLoader and InstanceType classes.
+	 *
+	 * - NoError indicates that no error occurred.
+	 * - OtherError indicates that an unspecified error occurred.
+	 * - TypeIDExists is returned	by registerInstanceType() if the ID of the type being registered already exists.
+	 * - TypeNotRegistered is returned by createInstance() and loadInstance() when the given type is not registered.
+	 * - InstExists is returned by createInstance() if the given instance directory is already an instance.
+	 * - NotAnInstance is returned by loadInstance() if the given instance directory is not a valid instance.
+	 * - WrongInstType is returned by loadInstance() if the given instance directory's type doesn't match the given type.
+	 */
+	enum InstTypeError
+	{
+		NoError = 0,
+		OtherError,
+		
+		TypeIDExists,
+		
+		TypeNotRegistered,
+		InstExists,
+		NotAnInstance,
+		WrongInstType
+	};
+	
+	/*!
+	 * \brief Registers the given InstanceType with the instance loader.
+	 *
+	 * \param type The InstanceType to register.
+	 * \return An InstTypeError error code.
+	 * - TypeIDExists if the given type's is already registered to another instance type.
+	 */
+	InstTypeError registerInstanceType(InstanceTypeInterface *type);
+	
+	/*!
+	 * \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 InstTypeError error code.
+	 * - TypeNotRegistered if the given type is not registered with the InstanceLoader.
+	 * - InstExists if the given instance directory is already an instance.
+	 */
+	InstTypeError createInstance(Instance *inst, const InstanceTypeInterface *type, const QString &instDir);
+	
+	/*!
+	 * \brief Loads an instance from the given directory.
+	 *
+	 * \param inst Pointer to store the loaded instance in.
+	 * \param type The type of instance to load.
+	 * \param instDir The instance's directory.
+	 * \return An InstTypeError error code.
+	 * - TypeNotRegistered if the given type is not registered with the InstanceLoader.
+	 * - NotAnInstance if the given instance directory isn't a valid instance.
+	 * - WrongInstType if the given instance directory's type isn't the same as the given type.
+	 */
+	InstTypeError loadInstance(Instance *inst, const InstanceTypeInterface *type, 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 InstTypeError error code.
+	 * - TypeNotRegistered if the instance's type is not registered with the InstanceLoader.
+	 * - NotAnInstance if the given instance directory isn't a valid instance.
+	 */
+	InstTypeError loadInstance(Instance *inst, const QString &instDir);
+	
+	/*!
+	 * \brief Finds an instance type with the given ID.
+	 * If one cannot be found, returns NULL.
+	 *
+	 * \param id The ID of the type to find.
+	 * \return The type with the given ID. NULL if none were found.
+	 */
+	const InstanceTypeInterface *findType(const QString &id);
+	
+	/*!
+	 * \brief Gets a list of the registered instance types.
+	 *
+	 * \return A list of instance types.
+	 */
+	InstTypeList typeList();
+	
+private:
+	InstanceLoader();
+	
+	QMap<QString, InstanceTypeInterface *> m_typeMap;
+	
+	static InstanceLoader loader;
+};
+
+#endif // INSTANCELOADER_H
diff --git a/libinstance/include/instancetypeinterface.h b/libinstance/include/instancetypeinterface.h
new file mode 100644
index 00000000..a061b9d2
--- /dev/null
+++ b/libinstance/include/instancetypeinterface.h
@@ -0,0 +1,86 @@
+/* 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 INSTANCETYPE_H
+#define INSTANCETYPE_H
+
+#include <QObject>
+
+#include "instanceloader.h"
+
+//! The InstanceTypeInterface's interface ID.
+#define InstanceTypeInterface_IID "net.forkk.MultiMC.InstanceTypeInterface/0.1"
+
+/*!
+ * \brief The InstanceType class is an interface for all instance types.
+ * InstanceTypes are usually provided by plugins.
+ * It handles loading and creating instances of a certain type. There should be 
+ * one of these for each type of instance and they should be registered with the 
+ * InstanceLoader.
+ * To create an instance, the InstanceLoader calls the type's createInstance() 
+ * function. Loading is done through the loadInstance() function.
+ */
+class InstanceTypeInterface
+{
+public:
+	friend class InstanceLoader;
+	
+	/*!
+	 * \brief Gets the ID for this instance type. 
+	 *        The type ID should be unique as it is used to identify the type 
+	 *        of instances when they are loaded.
+	 *        Changing this value at runtime results in undefined behavior.
+	 * \return This instance type's ID string. 
+	 */
+	virtual QString typeID() const = 0;
+	
+	/*!
+	 * \brief Gets the name of this instance type as it is displayed to the user.
+	 * \return The instance type's display name.
+	 */
+	virtual QString displayName() const = 0;
+	
+	/*!
+	 * \brief Gets a longer, more detailed description of this instance type.
+	 * \return The instance type's description.
+	 */
+	virtual QString description() const	= 0;
+	
+protected:
+	/*!
+	 * \brief Creates an instance and stores it in inst.
+	 * \param inst Pointer to store the created instance in.
+	 * \param instDir The instance's directory.
+	 * \return An InstTypeError error code.
+	 *         TypeNotRegistered if the given type is not registered with the InstanceLoader.
+	 *         InstExists if the given instance directory is already an instance.
+	 */
+	virtual InstanceLoader::InstTypeError createInstance(Instance *inst, const QString &instDir) const = 0;
+	
+	/*!
+	 * \brief Loads an instance from the given directory.
+	 * \param inst Pointer to store the loaded instance in.
+	 * \param instDir The instance's directory.
+	 * \return An InstTypeError error code.
+	 *         TypeNotRegistered if the given type is not registered with the InstanceLoader.
+	 *         NotAnInstance if the given instance directory isn't a valid instance.
+	 *         WrongInstType if the given instance directory's type isn't an instance of this type.
+	 */
+	virtual InstanceLoader::InstTypeError loadInstance(Instance *inst, const QString &instDir) const = 0;
+};
+
+Q_DECLARE_INTERFACE(InstanceTypeInterface, InstanceTypeInterface_IID)
+
+#endif // INSTANCETYPE_H
diff --git a/libinstance/include/instversion.h b/libinstance/include/instversion.h
new file mode 100644
index 00000000..c505c5a3
--- /dev/null
+++ b/libinstance/include/instversion.h
@@ -0,0 +1,53 @@
+/* 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 INSTVERSION_H
+#define INSTVERSION_H
+
+#include <QObject>
+
+#include "libinstance_config.h"
+
+class InstVersionList;
+
+class LIBMMCINST_EXPORT InstVersion : public QObject
+{
+	Q_OBJECT
+public:
+	// Constructs a new InstVersion with the given parent. The parent *must*
+	// be the InstVersionList that contains this InstVersion. The InstVersion
+	// should be added to the list immediately after being created as any calls
+	// to id() will likely fail unless the InstVersion is in a list.
+	explicit InstVersion(InstVersionList *parent = 0);
+	
+	// Returns this InstVersion's ID. This is usually just the InstVersion's index
+	// within its InstVersionList, but not always.
+	// If this InstVersion is not in an InstVersionList, returns -1.
+	virtual int id() const = 0;
+	
+	// Returns this InstVersion's name. This is displayed to the user in the GUI
+	// and is usually just the version number ("1.4.7"), for example.
+	virtual QString name() const = 0;
+	
+	// Returns this InstVersion's name. This is usually displayed to the user 
+	// in the GUI and specifies what kind of version this is. For example: it 
+	// could be "Snapshot", "Latest Version", "MCNostalgia", etc.
+	virtual QString type() const = 0;
+	
+	// Returns the version list that this InstVersion is a part of.
+	virtual InstVersionList *versionList() const;
+};
+
+#endif // INSTVERSION_H
diff --git a/libinstance/include/instversionlist.h b/libinstance/include/instversionlist.h
new file mode 100644
index 00000000..2cd9ed1e
--- /dev/null
+++ b/libinstance/include/instversionlist.h
@@ -0,0 +1,45 @@
+/* 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 INSTVERSIONLIST_H
+#define INSTVERSIONLIST_H
+
+#include <QObject>
+
+#include "libinstance_config.h"
+
+class InstVersion;
+
+// 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.
+class LIBMMCINST_EXPORT InstVersionList : public QObject
+{
+	Q_OBJECT
+public:
+	explicit InstVersionList();
+	
+	// Reloads the version list.
+	virtual void loadVersionList() = 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;
+};
+
+#endif // INSTVERSIONLIST_H
diff --git a/libinstance/include/libinstance_config.h b/libinstance/include/libinstance_config.h
new file mode 100644
index 00000000..2e6dc884
--- /dev/null
+++ b/libinstance/include/libinstance_config.h
@@ -0,0 +1,27 @@
+/* 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 LIBINSTANCE_CONFIG_H
+//#define LIBINSTANCE_CONFIG_H
+
+#include <QtCore/QtGlobal>
+
+#ifdef LIBMMCINST_LIBRARY
+#  define LIBMMCINST_EXPORT Q_DECL_EXPORT
+#else
+#  define LIBMMCINST_EXPORT Q_DECL_IMPORT
+#endif
+
+//#endif // LIBINSTANCE_CONFIG_H