StateMachine.java

package com.siondream.core.entity.fsm;

import ashley.core.Entity;

import com.badlogic.gdx.utils.Logger;
import com.badlogic.gdx.utils.ObjectMap;
import com.siondream.core.Env;

public class StateMachine {
	
	private Logger logger;
	private ObjectMap<Class<? extends State>, State> states;
	private State initialState;
	private State currentState;
	private State nextState;
	private Entity entity;
	
	public StateMachine(String name, Entity entity) {
		logger = new Logger(name, Env.debugLevel);
		logger.info("initialising");
		states = new ObjectMap<Class<? extends State>, State>();
		this.entity = entity;
	}
	
	public void addState(State state) {
		if (states.size == 0) {
			initialState = state;
		}
		
		states.put(state.getClass(), state);
	}
	
	public void update(float deltaTime) {
		if (currentState == null && initialState != null) {
			currentState = initialState;
			currentState.enter();
		}
		
		if (currentState != null) {
			currentState.update(deltaTime);
		}
		
		if (nextState != null && nextState != currentState) {
			logger.info("switching to state " + nextState.getClass().getSimpleName());
			currentState.exit();
			currentState = nextState;
			nextState = null;
			currentState.enter();
		}
	}
	
	public State getState() {
		return currentState;
	}
	
	public <T extends State> T getState(Class<T> stateClass) {
		return stateClass.cast(states.get(stateClass));
	}
	
	public void setNextState(Class<? extends State> stateClass) {
		nextState = states.get(stateClass);
	}
	
	public Entity getEntity() {
		return entity;
	}
}