package cz.cuni.amis.pogamut.defcon.utils;
   
   import java.lang.reflect.Method;
   import java.util.concurrent.CountDownLatch;
   import java.util.concurrent.TimeUnit;
   
   import javabot.PogamutJBotSupport;
   
   /**
   * Container for execution of queries from game info in the main thread from
   * other threads.
   * 
   * @author Radek 'Black_Hand' Pibil
   * 
   */
  public class SyncMethodExecContainer {
  	public volatile Method method;
  	public volatile Object[] parameters;
  	public volatile Object returnValue = null;
  	public volatile Object lock = new Object();
  	public volatile boolean used = false;
  
  	public SyncMethodExecContainer(Method method, Object[] parameters) {
  
  		if (method == null)
  			throw new IllegalArgumentException(
  					"method argument cannot be null.");
  
  		this.method = method;
  		this.parameters = parameters;
  	}
  
  	/**
  	 * Called in the main thread to execute herein contained method with a given
  	 * parameters and collecting the return value.
  	 */
  	public void execute() {
  		synchronized (lock) {
  			try {
  				this.returnValue = method.invoke(null, parameters);
  			} catch (Exception e) {
  				e.printStackTrace();
  			} finally {
  				latch.countDown();
  			}
  		}
  	}
  	
  	private final CountDownLatch latch = new CountDownLatch(1);
  
  	/**
  	 * Enqueue and wait for execution of the herein contained method in the main
  	 * thread.
  	 * 
  	 * @return
  	 */
  	public Object syncCallInMainThread() {
  
  		synchronized (lock) {
  			if (used)
  			throw new RuntimeException(
  					"Called twice! Previous call must finish first!");
  			used = true;
  		}
  
  
  		PogamutJBotSupport.addQuery(this);
  		try {
  			latch.await(10000, TimeUnit.MILLISECONDS);
  		} catch (InterruptedException e) {
  			PogamutJBotSupport.writeToConsole("Intteruped waiting");
  		} catch (Exception e) {
  			PogamutJBotSupport.writeToConsole("Exception!");
  			e.printStackTrace();
  			e.getCause().printStackTrace();
  		}
  
  		return returnValue;
  	}
  	
  	public Object getLock() {
  		return lock;
  	}
  }