adding new ai functional

OpenRA.Mods.RA/AI/StateMachine.cs

@@ -0,0 +1,79 @@
+#region Copyright & License Information
+/*
+ * Copyright 2007-2011 The OpenRA Developers (see AUTHORS)
+ * This file is part of OpenRA, which is free software. It is made
+ * available to you under the terms of the GNU General Public License
+ * as published by the Free Software Foundation. For more information,
+ * see COPYING.
+ */
+#endregion
+
+namespace OpenRA.Mods.RA.AI
+{
+	class StateMachine
+	{
+		//a pointer to the agent that owns this instance
+		private Squad owner;
+
+		private IState currentState;
+
+		//a record of the last state the agent was in
+		private IState previousState;
+
+		public StateMachine(Squad owner)
+		{
+			this.owner = owner;
+		}
+
+		public IState CurrentState
+		{
+			get { return currentState; }
+			set { currentState = value; }
+		}
+
+		public IState PreviousState
+		{
+			get { return previousState; }
+			set { previousState = value; }
+		}
+
+		//call this to update the FSM
+		public void UpdateFsm()
+		{
+			currentState.Execute(owner);
+		}
+
+		//change to a new state
+		//boolean variable isSaveCurrentState respons on save or not current state
+		public void ChangeState(IState newState, bool saveCurrentState)
+		{
+			if (saveCurrentState)
+				//keep a record of the previous state
+				previousState = currentState;
+
+			//call the exit method of the existing state
+			if(currentState != null)
+				currentState.Exit(owner);
+
+			//change state to the new state
+			if (newState != null)
+				currentState = newState;
+
+			//call the entry method of the new state
+			currentState.Enter(owner);
+		}
+
+		//change state back to the previous state
+		public void RevertToPreviousState(bool saveCurrentState)
+		{
+			ChangeState(previousState, saveCurrentState);
+		}
+	}
+
+	interface IState
+	{
+		void Enter(Squad bot);
+		void Execute(Squad bot);
+		void Exit(Squad bot);
+	}
+}