/*
 * This file is part of ADDIS (Aggregate Data Drug Information System).
 * ADDIS is distributed from http://drugis.org/.
 * Copyright © 2009 Gert van Valkenhoef, Tommi Tervonen.
 * Copyright © 2010 Gert van Valkenhoef, Tommi Tervonen, Tijs Zwinkels,
 * Maarten Jacobs, Hanno Koeslag, Florin Schimbinschi, Ahmad Kamal, Daniel
 * Reid.
 * Copyright © 2011 Gert van Valkenhoef, Ahmad Kamal, Daniel Reid, Florin
 * Schimbinschi.
 * Copyright © 2012 Gert van Valkenhoef, Daniel Reid, Joël Kuiper, Wouter
 * Reckman.
 * Copyright © 2013 Gert van Valkenhoef, Joël Kuiper.
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

package org.drugis.addis.entities;

import java.util.Collections;
import java.util.Comparator;
import java.util.Set;

import org.drugis.common.EqualsUtil;

public class MeasurementKey extends AbstractEntity implements Entity {

	private final Arm d_arm;
	private final WhenTaken d_wt;
	private final StudyOutcomeMeasure<? extends Variable> d_som;

	public MeasurementKey(StudyOutcomeMeasure<? extends Variable> som, Arm a, WhenTaken wt) {
		if (som.getValue() instanceof OutcomeMeasure && a == null) throw new NullPointerException("Arm may not be null for Endpoints/ADEs");
		if (wt == null) throw new NullPointerException("Moment of measurement may not be null");

		d_som = som;
		d_arm = a;
		d_wt = wt;
	}

	public Variable getVariable() {
		return d_som.getValue();
	}

	public StudyOutcomeMeasure<? extends Variable> getStudyOutcomeMeasure() {
		return d_som;
	}

	public Arm getArm() {
		return d_arm;
	}

	public WhenTaken getWhenTaken() {
		return d_wt;
	}

	@Override
	public String toString() {
		return "<" + d_som + ", " + d_arm + " at " + d_wt + ">";
	}

	@Override
	public boolean equals(Object o) {
		MeasurementKey other = matching(o);
		return other != null && d_som == other.d_som;
	}

	public boolean deepEquals(Object o)  {
		MeasurementKey other = matching(o);
		return other != null && EqualsUtil.equal(d_som, other.d_som);
	}

	public MeasurementKey matching(Object o) {
		if (o instanceof MeasurementKey) {
			MeasurementKey other = (MeasurementKey) o;
			if(EqualsUtil.equal(d_arm, other.d_arm)
				&& EqualsUtil.equal(d_wt, other.d_wt)) {
				return other;
			}
		}
		return null;
	}

	@Override
	public int hashCode() {
		int code = 1;
		code = code ^ (d_som == null ? 0 : System.identityHashCode(d_som));
		code = code ^ (d_arm == null ? 0 : d_arm.hashCode());
		code = code ^ (d_wt == null ? 0 : d_wt.hashCode());
		return code;
	}

	@Override
	public Set<? extends Entity> getDependencies() {
		return Collections.emptySet();
	}

	public static class MeasurementKeyComparator implements Comparator<MeasurementKey> {
		public int compare(MeasurementKey k0, MeasurementKey k1) {
			int variable = k0.getVariable().compareTo(k1.getVariable());
			if (variable == 0) {
				if (k0.getArm() != null) {
					if (k0.getArm().compareTo(k1.getArm()) == 0) {
						return k0.getWhenTaken().compareTo(k1.getWhenTaken());
					}
					return k0.getArm().compareTo(k1.getArm());
				} else if (k1.getArm() == null) {
					return k0.getWhenTaken().compareTo(k1.getWhenTaken());
				} else {
					return -1;
				}
			}
			return variable;
		}
	}
}