From 42874b90d93e245230a3d911ee19af920dc04296 Mon Sep 17 00:00:00 2001
From: Lynix <lynix680@gmail.com>
Date: Sat, 19 Mar 2016 12:21:07 +0100
Subject: [PATCH] SDK: Add StateMachine (FSM)

Former-commit-id: 8029f7cce71809ff1f661982d39750c48c86431f
---
 SDK/include/NDK/State.hpp        | 28 +++++++++++++++++++++++
 SDK/include/NDK/StateMachine.hpp | 39 ++++++++++++++++++++++++++++++++
 SDK/include/NDK/StateMachine.inl | 26 +++++++++++++++++++++
 3 files changed, 93 insertions(+)
 create mode 100644 SDK/include/NDK/State.hpp
 create mode 100644 SDK/include/NDK/StateMachine.hpp
 create mode 100644 SDK/include/NDK/StateMachine.inl

diff --git a/SDK/include/NDK/State.hpp b/SDK/include/NDK/State.hpp
new file mode 100644
index 000000000..0a113def3
--- /dev/null
+++ b/SDK/include/NDK/State.hpp
@@ -0,0 +1,28 @@
+// Copyright (C) 2015 Jérôme Leclercq
+// This file is part of the "Nazara Development Kit"
+// For conditions of distribution and use, see copyright notice in Prerequesites.hpp
+
+#pragma once
+
+#ifndef NDK_STATE_HPP
+#define NDK_STATE_HPP
+
+#include <NDK/Prerequesites.hpp>
+
+namespace Ndk
+{
+	class StateMachine;
+
+	class State
+	{
+		public:
+			State();
+			~State();
+
+			virtual void Enter(StateMachine& fsm) = 0;
+			virtual void Leave(StateMachine& fsm) = 0;
+			virtual bool Update(StateMachine& fsm, float elapsedTime) = 0;
+	};
+}
+
+#endif // NDK_STATE_HPP
\ No newline at end of file
diff --git a/SDK/include/NDK/StateMachine.hpp b/SDK/include/NDK/StateMachine.hpp
new file mode 100644
index 000000000..8d05f8335
--- /dev/null
+++ b/SDK/include/NDK/StateMachine.hpp
@@ -0,0 +1,39 @@
+// Copyright (C) 2015 Jérôme Leclercq
+// This file is part of the "Nazara Development Kit"
+// For conditions of distribution and use, see copyright notice in Prerequesites.hpp
+
+#pragma once
+
+#ifndef NDK_STATEMACHINE_HPP
+#define NDK_STATEMACHINE_HPP
+
+#include <NDK/Prerequesites.hpp>
+#include <NDK/State.hpp>
+#include <memory>
+
+namespace Ndk
+{
+	class StateMachine
+	{
+		public:
+			inline StateMachine();
+			StateMachine(const StateMachine&) = delete;
+			inline StateMachine(StateMachine&& fsm) = default;
+			inline ~StateMachine();
+
+			inline void ChangeState(std::shared_ptr<State> state);
+
+			inline bool Update(float elapsedTime);
+
+			inline StateMachine& operator=(StateMachine&& fsm) = default;
+			StateMachine& operator=(const StateMachine&) = delete;
+
+		private:
+			std::shared_ptr<State> m_currentState;
+			std::shared_ptr<State> m_nextState;
+	};
+}
+
+#include <NDK/StateMachine.inl>
+
+#endif // NDK_STATEMACHINE_HPP
\ No newline at end of file
diff --git a/SDK/include/NDK/StateMachine.inl b/SDK/include/NDK/StateMachine.inl
new file mode 100644
index 000000000..0a1e195c4
--- /dev/null
+++ b/SDK/include/NDK/StateMachine.inl
@@ -0,0 +1,26 @@
+// Copyright (C) 2015 Jérôme Leclercq
+// This file is part of the "Nazara Development Kit"
+// For conditions of distribution and use, see copyright notice in Prerequesites.hpp
+
+#include <NDK/StateMachine.hpp>
+#include <utility>
+
+namespace Ndk
+{
+	inline void StateMachine::ChangeState(std::shared_ptr<State> state)
+	{
+		m_nextState = std::move(state);
+	}
+
+	inline bool StateMachine::Update(float elapsedTime)
+	{
+		if (m_nextState)
+		{
+			m_currentState->Leave(*this);
+			m_currentState = std::move(m_nextState);
+			m_currentState->Enter(*this);
+		}
+
+		return m_currentState->Update(*this, elapsedTime);
+	}
+}