/*
 * Copyright (c) 2005-2010 KOM – Multimedia Communications Lab
 *
 * This file is part of PeerfactSim.KOM.
 * 
 * PeerfactSim.KOM 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
 * any later version.
 * 
 * PeerfactSim.KOM 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 PeerfactSim.KOM.  If not, see <http://www.gnu.org/licenses/>.
 *
 */

package de.tud.kom.p2psim.impl.topology.movement.modularosm.transition;

import java.util.Collection;
import java.util.Collections;
import java.util.LinkedHashMap;
import java.util.LinkedHashSet;
import java.util.LinkedList;
import java.util.List;
import java.util.Map;
import java.util.Random;
import java.util.Set;

import de.tud.kom.p2psim.api.scenario.ConfigurationException;
import de.tud.kom.p2psim.api.topology.movement.SimLocationActuator;
import de.tudarmstadt.maki.simonstrator.api.Randoms;
import de.tudarmstadt.maki.simonstrator.api.component.sensor.location.AttractionPoint;

/**
 * Abstract base class for Transition Strategies ({@link ITransitionStrategy}s) using {@link AttractionPoint}s.
 * 
 * @author Julian Zobel
 * @version 1.0, 23.01.2019
 */
public abstract class AbstractAttractionBasedTransitionStrategy implements ITransitionStrategy {

	protected Random rnd = Randoms.getRandom(AbstractAttractionBasedTransitionStrategy.class);
	
	protected Set<AttractionPoint> attractionPoints = new LinkedHashSet<>();
	
	protected Map<SimLocationActuator, AttractionPoint> assignments = new LinkedHashMap<>();
	
	protected Map<SimLocationActuator, AttractionPoint> lastAssignments = new LinkedHashMap<>();
	
	private List<AttractionAssignmentListener> listeners = new LinkedList<>();
	
	private long pauseTimeMin = 0;
	
	private long pauseTimeMax = 0;
	
	protected final static int EVENT_PAUSE_ENDED = 1;
	
	@Override
	public AttractionPoint getAssignment(SimLocationActuator comp) {
		return assignments.get(comp);
	}
	
	@Override
	public void addAttractionAssignmentListener(
			AttractionAssignmentListener listener) {
		listeners.add(listener);
	}
	
	@Override
	public void removeAttractionAssignmentListener(
			AttractionAssignmentListener listener) {
		listeners.remove(listener);
	}

	@Override
	public void setAttractionPoints(
			Collection<AttractionPoint> attractionPoints) {
		this.attractionPoints.clear();
		this.attractionPoints.addAll(attractionPoints);
	}

	@Override
	public Set<AttractionPoint> getAllAttractionPoints() {
		return Collections.unmodifiableSet(attractionPoints);
	}

	/**
	 * Notify all listeners of an updated attraction point assignment for the given component
	 * 
	 * @param comp
	 * @param attractionPoint
	 */
	protected void notifyListenersOfAssignmentUpdate(SimLocationActuator comp,
			AttractionPoint attractionPoint) {
		listeners.forEach(listener -> listener.updatedAttractionAssignment(comp, attractionPoint));
	}
	
	@Override
	public void updateTargetAttractionPoint(SimLocationActuator comp,
			AttractionPoint attractionPoint) {
		if(assignments.containsKey(comp)) {
			this.lastAssignments.put(comp, this.assignments.remove(comp));
		}
		this.assignments.put(comp, attractionPoint);
		notifyListenersOfAssignmentUpdate(comp, attractionPoint);	
	}
	
	protected long getPauseTime() {
		return (long) (rnd.nextDouble() * (pauseTimeMax-pauseTimeMin)) + pauseTimeMin;
	}
	
	public void setMinPauseTime(long minPauseTime) {
		if (minPauseTime < 0) {
			throw new ConfigurationException(
					"MinPauseTime should be >= 0!");
		}
		this.pauseTimeMin = minPauseTime;
	}

	public void setMaxPauseTime(long maxPauseTime) {
		if (maxPauseTime < 0) {
			throw new ConfigurationException(
					"MaxPauseTime should be >= 0!");
		}
		this.pauseTimeMax = maxPauseTime;
	}
}