Local and shared state

2 files changed, 64 insertions, 1 deletions

diff --git a/include/erebos/identity.h b/include/erebos/identity.h
index 7ba3f29..66a4afb 100644
--- a/include/erebos/identity.h
+++ b/include/erebos/identity.h
@@ -7,8 +7,14 @@ namespace erebos {
 class Identity
 {
 public:
+	Identity(const Identity &) = default;
+	Identity(Identity &&) = default;
+	Identity & operator=(const Identity &) = default;
+	Identity & operator=(Identity &&) = default;
+
 	static std::optional<Identity> load(const Ref &);
 	static std::optional<Identity> load(const std::vector<Ref> &);
+	std::vector<Ref> store(const Storage & st) const;
 
 	std::optional<std::string> name() const;
 	std::optional<Identity> owner() const;
@@ -38,9 +44,11 @@ public:
 	static Builder create(const Storage &);
 	Builder modify() const;
 
+	static const UUID sharedTypeId;
+
 private:
 	struct Priv;
-	const std::shared_ptr<const Priv> p;
+	std::shared_ptr<const Priv> p;
 	Identity(const Priv * p);
 	Identity(std::shared_ptr<const Priv> && p);
 };
diff --git a/include/erebos/state.h b/include/erebos/state.h
new file mode 100644
index 0000000..543e03c
--- /dev/null
+++ b/include/erebos/state.h
@@ -0,0 +1,55 @@
+#pragma once
+
+#include <erebos/identity.h>
+#include <erebos/uuid.h>
+
+#include <optional>
+
+namespace erebos {
+
+using std::optional;
+using std::vector;
+
+class LocalState
+{
+public:
+	LocalState();
+	explicit LocalState(const Ref &);
+	static LocalState load(const Ref & ref) { return LocalState(ref); }
+	Ref store(const Storage &) const;
+
+	static const UUID headTypeId;
+
+	const optional<Identity> & identity() const;
+	LocalState identity(const Identity &) const;
+
+	template<class T> optional<T> shared() const;
+	template<class T> LocalState shared(const vector<Stored<T>> &) const;
+	template<class T> LocalState shared(const Stored<T> & x) const { return shared({ x }); };
+	template<class T> LocalState shared(const Storage & st, const T & x)
+	{ return updateShared(T::sharedTypeId, x.store(st)); }
+
+private:
+	vector<Ref> lookupShared(UUID) const;
+	LocalState updateShared(UUID, const vector<Ref> &) const;
+
+	struct Priv;
+	std::shared_ptr<Priv> p;
+};
+
+template<class T>
+optional<T> LocalState::shared() const
+{
+	return T::load(lookupShared(T::sharedTypeId));
+}
+
+template<class T>
+LocalState LocalState::shared(const vector<Stored<T>> & v) const
+{
+	vector<Ref> refs;
+	for (const auto x : v)
+		refs.push_back(x.ref());
+	return updateShared(T::sharedTypeId, refs);
+}
+
+}