1 files changed, 34 insertions, 5 deletions

diff --git a/src/crepe/Component.h b/src/crepe/Component.h
index dc17721..52e06d5 100644
--- a/src/crepe/Component.h
+++ b/src/crepe/Component.h
@@ -1,5 +1,7 @@
 #pragma once
 
+#include <memory>
+
 #include "types.h"
 
 namespace crepe {
@@ -8,7 +10,7 @@ class ComponentManager;
 
 /**
  * \brief Base class for all components
- * 
+ *
  * This class is the base class for all components. It provides a common interface for all
  * components.
  */
@@ -16,7 +18,12 @@ class Component {
 public:
 	//! Whether the component is active
 	bool active = true;
-	//! The id of the GameObject this component belongs to
+	/**
+	 * \brief The id of the GameObject this component belongs to
+	 *
+	 * \note Only systems are supposed to use this member, but since friend
+	 * relations aren't inherited this needs to be public.
+	 */
 	const game_object_id_t game_object_id;
 
 protected:
@@ -24,14 +31,36 @@ protected:
 	 * \param id The id of the GameObject this component belongs to
 	 */
 	Component(game_object_id_t id);
-	//! Only the ComponentManager can create components
+	//! Only ComponentManager can create components
 	friend class ComponentManager;
 
-	Component(const Component &) = delete;
+	// components are never moved
 	Component(Component &&) = delete;
-	virtual Component & operator=(const Component &) = delete;
 	virtual Component & operator=(Component &&) = delete;
 
+protected:
+	/**
+	 * \name ReplayManager (Memento) functions
+	 * \{
+	 */
+	/**
+	 * \brief Save a snapshot of this component's state
+	 * \note This function should only be implemented on components that should be saved/restored
+	 * by ReplayManager.
+	 * \returns Unique pointer to a deep copy of this component
+	 */
+	virtual std::unique_ptr<Component> save() const;
+	//! Copy constructor (used by \c save())
+	Component(const Component &) = default;
+	/**
+	 * \brief Restore this component from a snapshot
+	 * \param snapshot Data to fill this component with (as returned by \c save())
+	 */
+	virtual void restore(const Component & snapshot);
+	//! Copy assignment operator (used by \c restore())
+	virtual Component & operator=(const Component &);
+	//! \}
+
 public:
 	virtual ~Component() = default;