/*
 * 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;


import java.util.LinkedHashSet;
import java.util.List;
import java.util.Map;
import java.util.Set;
import java.util.Vector;

import de.tud.kom.p2psim.api.scenario.ConfigurationException;
import de.tud.kom.p2psim.api.topology.Topology;
import de.tud.kom.p2psim.api.topology.movement.SimLocationActuator;
import de.tud.kom.p2psim.api.topology.movement.local.LocalMovementStrategy;
import de.tud.kom.p2psim.impl.topology.movement.modularosm.attraction.IAttractionGenerator;
import de.tud.kom.p2psim.impl.topology.movement.modularosm.attraction.hostcount.IAttractionPointHostCounter;
import de.tud.kom.p2psim.impl.topology.movement.modularosm.groups.MovementGroupContainer;
import de.tud.kom.p2psim.impl.topology.movement.modularosm.groups.SocialMovementGroup;
import de.tud.kom.p2psim.impl.topology.movement.modularosm.groups.groupencounter.IGroupEncounterBehavior;
import de.tud.kom.p2psim.impl.topology.movement.modularosm.groups.groupforming.IGroupFormingBehavior;
import de.tud.kom.p2psim.impl.topology.movement.modularosm.transition.IAttractionAssigmentStrategy;
import de.tud.kom.p2psim.impl.topology.util.PositionVector;
import de.tud.kom.p2psim.impl.topology.views.VisualizationTopologyView.VisualizationInjector;
import de.tudarmstadt.maki.simonstrator.api.Binder;
import de.tudarmstadt.maki.simonstrator.api.Event;
import de.tudarmstadt.maki.simonstrator.api.Time;
import de.tudarmstadt.maki.simonstrator.api.component.sensor.location.AttractionPoint;

/**
 * 
 * @author Julian Zobel
 * @version 1.0, 28.01.2020
 */
public class SocialGroupMovementModel extends ModularMovementModel {

	protected MovementGroupContainer groupContainer;
	protected IGroupFormingBehavior groupFormingBehavior;
	protected IGroupEncounterBehavior groupEncounterBehavior;
	protected IAttractionPointHostCounter attractionPointHostCounter;
	
	private Set<SimLocationActuator> singleHosts = new LinkedHashSet<SimLocationActuator>();
	private int numberOfSingleHosts;
		
	private boolean placeNodesAtAP = false;
	
	public void setPlaceNodes(boolean placeNodes) {
		this.placeNodesAtAP = placeNodes;
	}
	
	@Override
	public void initialize() {
		
		if (!initialized) {
			groupContainer = MovementGroupContainer.getInstance();
			attractionPointHostCounter.initialize(this);
			groupFormingBehavior.initialize(this);
			groupEncounterBehavior.initialize(this);
			
			// Choose single hosts
			if(numberOfSingleHosts > 0) {
				do {
					singleHosts.add(getRandomActuator());
				} while(singleHosts.size() < numberOfSingleHosts);
			}
			
			if (modelVisualisation == null) {
				modelVisualisation = new ModularMovementModelViz(this);
			}
			VisualizationInjector.injectComponent(modelVisualisation);
			if (mapVisualization != null) {
				VisualizationInjector.injectComponent(mapVisualization);
			}

			checkConfiguration();

			// setWayPointModel
			localMovementStrategy.setObstacleModel(Binder
					.getComponentOrNull(Topology.class).getObstacleModel());
			localMovementStrategy.setWaypointModel(Binder
					.getComponentOrNull(Topology.class).getWaypointModel());

			/*
			 * Scale depending on calculation interval, if interval != 1 Second.
			 */
			localMovementStrategy
					.setScaleFactor(timeBetweenMoveOperation / (double) Time.SECOND);
			
			attractionAssigment.addAttractionAssignmentListener(this);

			// This adds the mobile hosts (smartphones/users) to the transition
			// strategy
			for (SimLocationActuator ms : moveableHosts) {
				attractionAssigment.addComponent(ms);
				
				if(placeNodesAtAP)
					ms.updateCurrentLocation(attractionAssigment.getAssignment(ms));
				
			}
			
			setTimeBetweenMoveOperations(timeBetweenMoveOperation);

			// initial move
			move();

			initialized = true;
		
		}
	}

	
	
	
	/**
	 * Returns a random SimLocationActuator component from the set of moveable hosts.
	 * 
	 * @return SimLocationActuator
	 */
	private SimLocationActuator getRandomActuator() {
		
		int index = rand.nextInt(moveableHosts.size());
		int i = 0;
		for(SimLocationActuator actuator : moveableHosts) {
			if(i == index) {
				return actuator;
			}
			i++;
		}

		return null;
	}
	
	/**
	 * The movement model. 
	 * 1) Updates the number of hosts within each attraction point.
	 * 2) Creates and deletes groups, if necessary.
	 * 3) Applies encounter action to meeting groups.
	 * 4) Moves the hosts using doGroupMovement, movement style depends on role of the host (Leader, Participant, Single)
	 */
	@Override
	protected void move() {	
		
		// Update the number of hosts within each attraction point.
		attractionPointHostCounter.updateHostCount();

		// Check POIs if groups can be created. Delete groups, if destination reached.
		groupFormingBehavior.manageGroups();
		
		// Checks if groups encounter each other and applies a specified action to these groups.		
		groupEncounterBehavior.handleEncounters();
	
		/*	
		 * Moves all nodes according to definition in group movement method
		 */
		for (SimLocationActuator component : moveableHosts) {
			assert currentTargets.containsKey(component);
			doGroupMovement(component, currentTargets.get(component));
		}
		Event.scheduleWithDelay(timeBetweenMoveOperation, this, null, EVENT_MOVE);
	}
		
	/**
	 * Applies movement of the host according to different circumstances:
	 * 
	 * Towards Destination: Host is not a group member || Group has met at meeting point successfully.
	 * Towards MeetingPoint: Host if group member and has not reached meeting point yet.
	 * No movement: Host reached meeting point, but still waits for group members to arrive.
	 * 
	 * @param SimLocationActuator The host to move.
	 * @param PositionVector Destination of the host.
	 */
	protected void doGroupMovement(SimLocationActuator host, PositionVector destination) {
		// Single Host Movement
		if(singleHosts.contains(host) || !groupContainer.isGroupMember(host)) {			
			doLocalMovement(host, destination);
		}
				
		// Group Related Movement
		else if(groupContainer.isGroupMember(host)){
			if(movesToGroupMeetingPoint(host)) {
				if(hostIsAtMeetingPoint(host)) {
					if(groupAtMP(host)) {
						SocialMovementGroup group = groupContainer.getGroupOfHost(host);
						AttractionPoint currAp = group.getLeader().getCurrentTargetAttractionPoint();
						PositionVector currDest = group.getDestination();
						group.setMeetingPoint(currDest);
						
						for(SimLocationActuator participant : group.getMembers()) {
							attractionAssigment.updateTargetAttractionPoint(participant, currAp);
						}
					}
				}
				// MP not reached. Move to MP.
				else {
					PositionVector mp = groupContainer.getGroupOfHost(host).getMeetingPoint();
					doLocalMovement(host, mp);
				}
			}
			// MP reached. Move to destination.
			else {
				if(groupContainer.isLeader(host)) {
					if(!groupContainer.isWaiting(groupContainer.getGroupOfHost(host))) {						
						doLocalMovement(host, destination);
					}
				}
				else {
					followLeader(host);
				}
			}
		}
	}
	
	/* 
	 * =====================================================================================================
	 * === MEETING POINT FUNCTIONS
	 * =====================================================================================================
	 */
	/**
	 * Checks if a host is currently on its way to a meeting point or to its destination.
	 * Returns true if moving towards meeting point, false else.
	 * 
	 * @param SimLocationActuator The host to be checked.
	 * @return Boolean
	 */
	private boolean movesToGroupMeetingPoint(SimLocationActuator host) {
		PositionVector mp = groupContainer.getGroupOfHost(host).getMeetingPoint();
		PositionVector dest = groupContainer.getGroupOfHost(host).getDestination();
		if(mp != dest) {
			return true;
		}
		return false;
	}

	/**
	 * Returns true, if all group members of a host including the host itself reached the meeting point, false else.
	 * 
	 * @param SimLocationActuator The host to be checked.
	 * @return Boolean
	 */
	private boolean groupAtMP(SimLocationActuator host) {
		Set<SimLocationActuator> participants = groupContainer.getGroupMembers(host);
		int counter = 0;
		for(SimLocationActuator participant : participants) {
			if(hostIsAtMeetingPoint(participant)) {
				counter++;
			}
		}
		if(counter == participants.size()) {			
			return true;
		}
		return false;
	}

	/**
	 * Returns true if the host reached its current meeting point, false else.
	 * 
	 * @param SimLocationActuator The host to be checked.
	 * @return Boolean
	 * 
	 */
	private boolean hostIsAtMeetingPoint(SimLocationActuator host) {
		
		PositionVector currMP = groupContainer.getGroupOfHost(host).getMeetingPoint();
		
		// Setting the required distance to the meeting point to maximum of 2 meters
		// This is equivalent to a distance of group members in real life
		double distance = host.getLastLocation().distanceTo(currMP);
		if(distance <= 5) {			
			return true;
		}
		return false;
	}

	/* 
	 * =====================================================================================================
	 * === MOVEMENT FUNCTIONS
	 * =====================================================================================================
	 */
	

	/**
	 * Host position adapts to leaders position by taking the leader position and adding a small offset
	 * 
	 * @param SimLocationActuator The host to be moved.
	 */
	private void followLeader(SimLocationActuator host) {
		SimLocationActuator leader = groupContainer.getGroupOfHost(host).getLeader();
		
		if(leader.getCurrentTargetAttractionPoint() == null) {
			System.out.println();
		}
		
		AttractionPoint leaderDestination = leader.getCurrentTargetAttractionPoint();
		AttractionPoint hostDestination = host.getCurrentTargetAttractionPoint();
		
		// Update target attraction point if not already done
		if(leaderDestination != null && hostDestination != leaderDestination) {
			attractionAssigment.updateTargetAttractionPoint(host, leaderDestination);
		}
		
		int o = 10;
		
		// Assign small offset to the host depending on the leaders position.
		PositionVector leaderPos = leader.getRealPosition();
		PositionVector offset = new PositionVector(rand.nextInt(o), rand.nextInt(o));
		PositionVector newPos = leaderPos.plus(offset);

		// Update location of host, which will be around the leaders location.
		host.updateCurrentLocation(newPos);
	}


	/* 
	 * =====================================================================================================
	 * === GETTER AND SETTER FUNCTIONS
	 * =====================================================================================================
	 */
	
	public void setGroupFormingBehavior(IGroupFormingBehavior defaultGroupForming) {
		if (defaultGroupForming == null) {
			throw new ConfigurationException(
					"GroupFormingStrategy is missing in ModularMovementModel!");
		}
		this.groupFormingBehavior = defaultGroupForming;
	}

	public void setGroupEncounterBehavior(IGroupEncounterBehavior defaultGroupEncounterBehavior) {
		if (defaultGroupEncounterBehavior == null) {
			throw new ConfigurationException(
					"GroupEncounterStrategy is missing in ModularMovementModel!");
		}
		this.groupEncounterBehavior = defaultGroupEncounterBehavior;
	}

	public void setAttractionPointHostCounter(IAttractionPointHostCounter attractionPointHostCounter) {
		if (attractionPointHostCounter == null) {
			throw new ConfigurationException(
					"HostCountStrategy is missing in ModularMovementModel!");
		}
		this.attractionPointHostCounter = attractionPointHostCounter;
	}

	public IAttractionAssigmentStrategy getAttractionAssignmentStrategy() {
		return attractionAssigment;
	}
	
	public IGroupFormingBehavior getGroupFormingBehavior() {
		return groupFormingBehavior;
	}

	public LocalMovementStrategy getMovementStrategy() {
		return localMovementStrategy;
	}

	public IAttractionPointHostCounter getAttractionPointHostCounter() {
		return attractionPointHostCounter;
	}
	
	public void setNumberOfSingleHosts(int numberOfSingleHosts) {
		this.numberOfSingleHosts = numberOfSingleHosts;
	}
	
	public Set<SimLocationActuator> getSingleHosts(){
		return singleHosts;
	}	

	public Map<SimLocationActuator, PositionVector> getCurrentTargets(){
		return currentTargets;
	}
	
	/**
	 * Only for visualization!
	 * 
	 * @return
	 */
	public List<AttractionPoint> getAttractionPoints() {
		return new Vector<AttractionPoint>(IAttractionGenerator.attractionPoints);
	}
	
	

}