package nl.tudelft.goal.EIS2Java.handlers;
   
   import java.lang.reflect.InvocationTargetException;
   import java.lang.reflect.Method;
   import java.util.HashMap;
   import java.util.LinkedList;
   import java.util.Map;
   
   import nl.tudelft.goal.EIS2Java.exception.TranslationException;
  import nl.tudelft.goal.EIS2Java.translation.Translator;
  import nl.tudelft.goal.EIS2Java.util.EIS2JavaUtil;
  
  import eis.exceptions.ActException;
  import eis.exceptions.EntityException;
  import eis.iilang.Action;
  import eis.iilang.Parameter;
  import eis.iilang.Percept;
  
  public class SynchronizedActionHandler extends ActionHandler {
  
  	protected final Map<String, Method> actionMethods;
  	protected final AsynchronousEntity entity;
  
  	public SynchronizedActionHandler(AsynchronousEntity entity) throws EntityException {
  		this.entity = entity;
  		this.actionMethods = EIS2JavaUtil.processActionAnnotations(entity.getClass());
  	}
  
  	@Override
  	public final boolean isSupportedByEntity(Action action) {
  		String actionName = EIS2JavaUtil.getNameOfAction(action);
  		return actionMethods.get(actionName) != null;
  	}
  
  	@Override
  	public final Percept performAction(Action action) throws ActException {
  		String actionName = EIS2JavaUtil.getNameOfAction(action);
  		Method actionMethod = actionMethods.get(actionName);
  		if (actionMethod == null) {
  			throw new ActException(ActException.FAILURE, "Entity does not support action: " + action);
  		}
  
  		// workaround/fix for an EIS issue. #1986.
  		try {
  			return performAction(entity, actionMethod, action.getName(), action.getParameters());
  		} catch (Exception e) {
  			if (e instanceof ActException) {
  				throw (ActException) e;
  			}
  			throw new ActException(ActException.FAILURE, "execution of action " + action + "failed", e);
  		}
  	}
  
  	/**
  	 * Performs the action method on the given method using the parameters. The
  	 * returned {@link Percept} will have the same name as the action.
  	 * 
  	 * @param entity
  	 *            The entity to perform the method on.
  	 * @param method
  	 *            The method to invoke on the entity.
  	 * @param actionName
  	 *            The name of the action that is being performed.
  	 * @param parameters
  	 *            The parameters to the method (before translation).
  	 * @return The percept generated by the action.
  	 * @throws ActException
  	 *             if the action can not be performed for any reason.
  	 */
  	private Percept performAction(AsynchronousEntity entity, Method method, String actionName,
  			LinkedList<Parameter> parameters) throws ActException {
  		Translator translator = Translator.getInstance();
  
  		Class<?>[] parameterTypes = method.getParameterTypes();
  
  		Object[] arguments = new Object[parameters.size()];
  		// Doing it the hard way because LinkedList.get(index) sucks!
  		int i = 0;
  		for (Parameter parameter : parameters) {
  			try {
  				arguments[i] = translator.translate2Java(parameter, parameterTypes[i]);
  			} catch (TranslationException e) {
  				throw new ActException(ActException.FAILURE, "Action " + actionName + " with parameters " + parameters
  						+ " failed to be translated", e);
  			}
  			i++;
  		}
  
  		Object returnValue;
  		try {
  			entity.acquire();
  			try {
  				returnValue = method.invoke(entity, arguments);
  			} finally {
  				entity.release();
  			}
  
  		} catch (IllegalArgumentException e) {
  			throw new ActException(ActException.FAILURE, "Action " + actionName + " with parameters " + parameters
 					+ " failed to execute", e);
 		} catch (IllegalAccessException e) {
 			throw new ActException(ActException.FAILURE, "Action " + actionName + " with parameters " + parameters
 					+ " failed to execute", e);
 		} catch (InvocationTargetException e) {
 			throw new ActException(ActException.FAILURE, "Action " + actionName + " with parameters " + parameters
 					+ " failed to execute", e);
 		} catch (InterruptedException e) {
 			throw new ActException(ActException.FAILURE, "Action " + actionName + " with parameters " + parameters
 					+ " failed to execute. Interupted while aquiring the entity.", e);
 		}
 		if (returnValue == null) {
 			return null;
 		} else {
 			try {
 				return new Percept(actionName, translator.translate2Parameter(returnValue));
 			} catch (TranslationException e) {
 				throw new ActException(ActException.FAILURE, "Action " + actionName + " with parameters " + parameters
 						+ " failed to return a proper failue", e);
 			}
 		}
 	}
 
 }