HuntPlan.java

package jadex.bdi.examples.hunterprey_classic.creature.hunters.ldahunter;

import jadex.bdi.examples.hunterprey_classic.Hunter;
import jadex.bdi.examples.hunterprey_classic.Location;
import jadex.bdi.examples.hunterprey_classic.Prey;
import jadex.bdi.examples.hunterprey_classic.Vision;
import jadex.bdi.examples.hunterprey_classic.creature.hunters.ldahunter.potentialfield.JointField;
import jadex.bdi.examples.hunterprey_classic.creature.hunters.ldahunter.potentialfield.PotentialFrame;
import jadex.bdi.runtime.IGoal;
import jadex.bdi.runtime.Plan;

/**
 * A plan skeleton. Custom code goes into the body() method.
 */
public class HuntPlan extends Plan {
	Hunter myself;
	Location myLoc;
	JointField jf;
	PotentialFrame pf;
	Vision vis;
	Prey prey;

	/**
	 * The plan body. The plan is finished when this method returns.
	 */
	public void body() {
		// set variables
		vis = (Vision) (getBeliefbase()).getBelief("vision").getFact();
		while (vis == null) {
			waitFor(500);
			vis = (Vision) getBeliefbase().getBelief("vision").getFact();
		}
		myself = (Hunter) getBeliefbase().getBelief("my_self").getFact();
		myLoc = myself.getLocation();

		jf = (JointField) getBeliefbase().getBelief("potential_field")
				.getFact();
		pf = (PotentialFrame) getBeliefbase().getBelief("potential_window")
				.getFact();

		prey = (Prey) getBeliefbase().getBelief("next_sheep").getFact();

		jf.update(vis.getObjects(), myself);

		if (!eating())
			foolAround();
	}

	/**
	 * @return true if it was eating
	 */
	protected boolean eating() {
		if (prey != null) {
			if (prey.getLocation().equals(myLoc)) { // eat it
				IGoal eat = createGoal("eat");
				eat.getParameter("object").setValue(prey);
				jf.eaten(prey);
				pf.update(jf, myLoc, myLoc.getX(), myLoc.getY());
				dispatchSubgoalAndWait(eat); // / ------------->
				return true;
			}
		}
		return false;
	}

	/** 
   */
	protected void foolAround() {
		Location to;
		String dir = null;

		to = prey != null ? prey.getLocation() : jf.getBestLocation();
		pf.update(jf, myLoc, to.getX(), to.getY());

		while (myself.getLocationDistance(myLoc, to) > 1
				&& jf.getNearerLocation(to)) {/**/
		}

		if (myself.getLocationDistance(myLoc, to) == 1) {
			String dirs[] = myself.getDirections(myLoc, to);
			if (dirs.length > 0)
				dir = dirs[0];
		}

		if (dir == null) {
			String posDirs[] = myself.getPossibleDirections(vis.getObjects());
			String lastDir = (String) getBeliefbase().getBelief(
					"last_direction").getFact();
			dir = posDirs[randomInt(posDirs.length)];
			for (int i = 0; i < posDirs.length; i++) {
				if (lastDir == posDirs[i] && Math.random() > 0.2) {
					dir = lastDir;
					break;
				}
			}
		}

		getLogger().info("Moving " + dir + " to " + to);

		IGoal move = createGoal("move");
		move.getParameter("direction").setValue(dir);
		getBeliefbase().getBelief("last_direction").setFact(dir);
		dispatchSubgoalAndWait(move); // / ------------->
	}

	/**
	 * @param max
	 * @return integer less than max
	 */
	int randomInt(final int max) {
		int rnd = (int) Math.floor(Math.random() * max);
		return (rnd < max) ? rnd : max - 1;
	}

}