11 files changed, 189 insertions, 0 deletions
diff --git a/src/crepe/CMakeLists.txt b/src/crepe/CMakeLists.txt
index d938eb8..8e3a81c 100644
--- a/src/crepe/CMakeLists.txt
+++ b/src/crepe/CMakeLists.txt
@@ -31,6 +31,8 @@ target_sources(crepe PUBLIC FILE_SET HEADERS FILES
 	Collider.h
 	SDLContext.h
 	RenderSystem.h
+	Proxy.h
+	Proxy.hpp
 )
 
 add_subdirectory(api)
diff --git a/src/crepe/Proxy.h b/src/crepe/Proxy.h
new file mode 100644
index 0000000..97b8afa
--- /dev/null
+++ b/src/crepe/Proxy.h
@@ -0,0 +1,23 @@
+#pragma once
+
+#include <memory>
+
+#include "ProxyHandler.h"
+
+namespace crepe {
+
+template <typename T>
+class Proxy {
+public:
+	Proxy & operator = (const T &);
+	operator const T & () const;
+
+public:
+	Proxy(std::unique_ptr<ProxyHandler<T>> handler) : val(std::move(handler)) {}
+private:
+	std::unique_ptr<ProxyHandler<T>> val = nullptr;
+};
+
+}
+
+#include "Proxy.hpp"
diff --git a/src/crepe/Proxy.hpp b/src/crepe/Proxy.hpp
new file mode 100644
index 0000000..7f23716
--- /dev/null
+++ b/src/crepe/Proxy.hpp
@@ -0,0 +1,19 @@
+#pragma once
+
+#include "Proxy.h"
+
+namespace crepe {
+
+template <typename T>
+Proxy<T> & Proxy<T>::operator = (const T & val) {
+	this->val->set(val);
+	return *this;
+}
+
+template <typename T>
+Proxy<T>::operator const T & () const {
+	return this->val->get();
+}
+
+}
+
diff --git a/src/crepe/ProxyHandler.h b/src/crepe/ProxyHandler.h
new file mode 100644
index 0000000..ff2be70
--- /dev/null
+++ b/src/crepe/ProxyHandler.h
@@ -0,0 +1,13 @@
+#pragma once
+
+namespace crepe {
+
+template <typename T>
+class ProxyHandler {
+public:
+	virtual void set(const T &) = 0;
+	virtual const T & get() = 0;
+};
+
+}
+
diff --git a/src/crepe/api/CMakeLists.txt b/src/crepe/api/CMakeLists.txt
index 0bb1263..97bc6b1 100644
--- a/src/crepe/api/CMakeLists.txt
+++ b/src/crepe/api/CMakeLists.txt
@@ -11,6 +11,7 @@ target_sources(crepe PUBLIC
 	Texture.cpp
 	AssetManager.cpp
 	Sprite.cpp
+	SaveManager.cpp
 )
 
 target_sources(crepe PUBLIC FILE_SET HEADERS FILES
@@ -28,4 +29,6 @@ target_sources(crepe PUBLIC FILE_SET HEADERS FILES
 	Texture.h 
 	AssetManager.h 
 	AssetManager.hpp
+	SaveManager.h
+	SaveManager.hpp
 )
diff --git a/src/crepe/api/SaveManager.cpp b/src/crepe/api/SaveManager.cpp
new file mode 100644
index 0000000..a05e2c7
--- /dev/null
+++ b/src/crepe/api/SaveManager.cpp
@@ -0,0 +1,9 @@
+#include "SaveManager.h"
+
+using namespace crepe::api;
+
+SaveManager & SaveManager::get_instance() {
+	static SaveManager instance;
+	return instance;
+}
+
diff --git a/src/crepe/api/SaveManager.h b/src/crepe/api/SaveManager.h
new file mode 100644
index 0000000..37463ca
--- /dev/null
+++ b/src/crepe/api/SaveManager.h
@@ -0,0 +1,39 @@
+#pragma once
+
+#include "../Proxy.h"
+
+namespace crepe::api {
+
+class SaveManager {
+public:
+	//! Get a reference to a value and initialize it with a value if it does not yet exist
+	template <typename T>
+	Proxy<T> & get(const char * key, const T & default_value);
+
+	//! Get a reference to a value
+	template <typename T>
+	Proxy<T> & get(const char * key);
+
+	//! Set a value directly
+	template <typename T>
+	void set(const char * key, const T & value);
+
+	//! Check if the save file has a value for this \c key
+	bool has(const char * key);
+
+private:
+	SaveManager();
+	virtual ~SaveManager();
+
+public:
+	// singleton
+	static SaveManager & get_instance();
+	SaveManager(const SaveManager &) = delete;
+	SaveManager(SaveManager &&) = delete;
+	SaveManager & operator = (const SaveManager &) = delete;
+	SaveManager & operator = (SaveManager &&) = delete;
+};
+
+}
+
+#include "SaveManager.hpp"
diff --git a/src/crepe/api/SaveManager.hpp b/src/crepe/api/SaveManager.hpp
new file mode 100644
index 0000000..44f58ed
--- /dev/null
+++ b/src/crepe/api/SaveManager.hpp
@@ -0,0 +1,4 @@
+#pragma once
+
+#include "SaveManager.h"
+
diff --git a/src/example/CMakeLists.txt b/src/example/CMakeLists.txt
index fea6f60..8158d60 100644
--- a/src/example/CMakeLists.txt
+++ b/src/example/CMakeLists.txt
@@ -24,3 +24,6 @@ add_example(rendering)
 add_example(asset_manager)
 add_example(particle)
 add_example(physics)
+add_example(savemgr)
+add_example(proxy)
+
diff --git a/src/example/proxy.cpp b/src/example/proxy.cpp
new file mode 100644
index 0000000..7e2efa5
--- /dev/null
+++ b/src/example/proxy.cpp
@@ -0,0 +1,47 @@
+/** \file
+ * 
+ * Standalone example for usage of the proxy type
+ */
+
+#include <crepe/api/Config.h>
+#include <crepe/util/log.h>
+#include <crepe/Proxy.h>
+
+using namespace std;
+using namespace crepe;
+using namespace crepe::util;
+
+template <typename T>
+class MyProxyHandler : public ProxyHandler<T> {
+public:
+	virtual void set(const T & val) {
+		dbg_logf("set %s", to_string(val).c_str());
+		this->val = val;
+	}
+
+	virtual const T & get() {
+		dbg_logf("get %s", to_string(this->val).c_str());
+		return this->val;
+	}
+
+private:
+	T val = 0;
+};
+
+void test_ro(const int & val) { }
+void test_rw(int & val) { }
+
+int main() {
+	auto & cfg = api::Config::get_instance();
+	cfg.log.level = util::LogLevel::DEBUG;
+
+	Proxy<int> val(make_unique<MyProxyHandler<int>>());
+
+	val = 54;
+
+	test_ro(val); // this is allowed
+	// test_rw(val); // this should throw a compile error
+
+	return 0;
+}
+
diff --git a/src/example/savemgr.cpp b/src/example/savemgr.cpp
new file mode 100644
index 0000000..810947d
--- /dev/null
+++ b/src/example/savemgr.cpp
@@ -0,0 +1,27 @@
+/** \file
+ * 
+ * Standalone example for usage of the save manager
+ */
+
+#include <cassert>
+#include <crepe/util/log.h>
+#include <crepe/api/SaveManager.h>
+
+using namespace crepe;
+using namespace crepe::api;
+using namespace crepe::util;
+
+int main() {
+	const char * key = "mygame.test";
+	SaveManager & mgr = SaveManager::get_instance();
+
+	auto & prop = mgr.get<unsigned int>(key, 1);
+	prop = 2;
+
+	mgr.set<unsigned int>(key, 3);
+
+	assert(true == mgr.has(key));
+
+	return 0;
+}
+