ai.libs.jaicore.planning.hierarchical.problems.htn.CostSensitivePlanningToSearchProblemReduction Maven / Gradle / Ivy

package ai.libs.jaicore.planning.hierarchical.problems.htn;

import ai.libs.jaicore.basic.IObjectEvaluator;
import ai.libs.jaicore.basic.algorithm.reduction.AlgorithmicProblemReduction;
import ai.libs.jaicore.planning.core.EvaluatedPlan;
import ai.libs.jaicore.planning.core.Plan;
import ai.libs.jaicore.search.model.other.EvaluatedSearchGraphPath;
import ai.libs.jaicore.search.model.other.SearchGraphPath;
import ai.libs.jaicore.search.probleminputs.GraphSearchInput;
import ai.libs.jaicore.search.probleminputs.GraphSearchWithPathEvaluationsInput;

public class CostSensitivePlanningToSearchProblemReduction, I1 extends IHTNPlanningProblem, I2 extends GraphSearchWithPathEvaluationsInput, O2 extends EvaluatedSearchGraphPath>
implements IHierarchicalPlanningToGraphSearchReduction, EvaluatedPlan, I2, O2> {

	private final IHierarchicalPlanningToGraphSearchReduction, SearchGraphPath> baseReduction;
	private final AlgorithmicProblemReduction, ? super EvaluatedSearchGraphPath, I2, O2> forwardReduction;

	public CostSensitivePlanningToSearchProblemReduction(final IHierarchicalPlanningToGraphSearchReduction, SearchGraphPath> baseReduction,
			final AlgorithmicProblemReduction, ? super EvaluatedSearchGraphPath, I2, O2> forwardReduction) {
		super();
		this.baseReduction = baseReduction;
		this.forwardReduction = forwardReduction;
	}

	/**
	 * This method operates in three steps:
	 * 1) it derives a general graph search problem from the given planning problem
	 * 2) it combines the obtained graph search problem with a path evaluation function into a GrahhSearchWithPathEvaluationsInput
	 * 3) it derives a potentially more informed GraphSearchInput
	 *
	 * The last process is called the forward reduction. The output does not change.
	 */
	@Override
	public I2 encodeProblem(final CostSensitiveHTNPlanningProblem problem) {
		IObjectEvaluator, V> solutionEvaluator = solutionPath -> problem.getPlanEvaluator().evaluate(CostSensitivePlanningToSearchProblemReduction.this.baseReduction.decodeSolution(solutionPath));
		return this.forwardReduction.encodeProblem(new GraphSearchWithPathEvaluationsInput<>(this.baseReduction.encodeProblem(problem.getCorePlanningProblem()).getGraphGenerator(), solutionEvaluator));
	}

	@Override
	public EvaluatedPlan decodeSolution(final O2 solution) {
		return new EvaluatedPlan<>(this.baseReduction.decodeSolution(solution), solution.getScore());
	}
}