package jcgp.backend.modules.mutator;

import jcgp.backend.function.Function;
import jcgp.backend.population.Chromosome;
import jcgp.backend.population.MutableElement;
import jcgp.backend.population.Node;
import jcgp.backend.population.Output;
import jcgp.backend.resources.Resources;
import jcgp.backend.resources.parameters.DoubleParameter;
import jcgp.backend.resources.parameters.Parameter;
import jcgp.backend.resources.parameters.ParameterStatus;

public class PointMutator implements Mutator {
	
	private DoubleParameter mutationRate;

	public PointMutator(final Resources resources) {
		mutationRate = new DoubleParameter(50, "Percent mutation", false, false) {
			@Override
			public void validate(double newValue) {
				if (newValue <= 0 || newValue > 100) {
					status = ParameterStatus.INVALID;
					status.setDetails("Mutation rate must be > 0 and <= 100");
				} else if ((int) ((newValue / 100) * resources.getDouble("nodes")) <=  0) {
					status = ParameterStatus.WARNING;
					status.setDetails("With mutation rate " + mutationRate.get() + ", 0 genes will be mutated.");
				} else {
					status = ParameterStatus.VALID;
				}
			}
		};
	}

	@Override
	public void mutate(Chromosome chromosome, Resources resources) {
		int mutations = (int) ((mutationRate.get()) * ((((resources.getDouble("nodes")) + (resources.getDouble("outputs")))) / 100));
		for (int i = 0; i < mutations; i++) {
			MutableElement m = chromosome.getRandomMutableElement();
			
			if (m instanceof Output) {
				m.setConnection(0, chromosome.getRandomConnection());
			} else if (m instanceof Node) {
				int geneType = resources.getRandomInt(1 + resources.getInt("arity"));
				if (geneType < 1) {
					Function f = resources.getRandomFunction();
					((Node) m).setFunction(f);
				} else {
					m.setConnection(resources.getRandomInt(resources.getInt("arity")), chromosome.getRandomConnection(((Node) m).getColumn()));
				}
			}
		}
	}

	@Override
	public Parameter[] getLocalParameters() {
		return new Parameter[] {mutationRate};
	}

	@Override
	public String toString() {
		return "Point mutation";
	}

}