package ch.epfl.maze.physical.stragegies.reducer;

import ch.epfl.maze.physical.World;
import ch.epfl.maze.util.Direction;
import ch.epfl.maze.util.Vector2D;

import java.util.Set;

/**
 * A choice filter that can exclude choices.
 *
 * @author Pacien TRAN-GIRARD
 */
public interface ChoiceReducer {

    /**
     * Reduces the Direction choices by eliminating the improper ones from the given choices.
     *
     * @param choices The choices left to the animal
     * @return A subset of possible direction of the animal, chosen in {@code choices}
     */
    Set<Direction> reduce(Set<Direction> choices);

    /**
     * Reduces the Direction choices by eliminating the improper ones from the given choices.
     * In this variation, the animal knows the world entirely. It can therefore
     * use the position of other animals in the world to move more effectively.
     *
     * @param choices The choices left to the animal
     * @return A subset of possible direction of the animal, chosen in {@code choices}
     */
    Set<Direction> reduce(Set<Direction> choices, World world);

}