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package com.camilstaps.route66;

import OO14route66.Car;
import java.util.HashMap;
import java.util.Map;

/**
 *
 * @author pieterkoopman
 */
public class Overviewer {
    
    private static Overviewer instance;
    
    Map<Car, Integer> locations;
    
    protected Overviewer() {
        locations = new HashMap<>();
    }
    
    public static Overviewer getInstance() {
        if (instance == null) {
            instance = new Overviewer();
        }
        return instance;
    }
    
    public synchronized void setLocation(Car car, int location) {
        if (locations.containsKey(car)) {
            locations.remove(car);
        } 
        locations.put(car, location);
    }
    
    public synchronized boolean isSafeLocation(Car car, int requested_location) {
        for (Map.Entry<Car, Integer> location : locations.entrySet()) {
            Car that_car = location.getKey();
            if (that_car != car && 
                    that_car.getDirection() == car.getDirection() &&
                    that_car.getLocation() > requested_location &&
                    that_car.getLocation() < requested_location + Car.CARLENGTH + Car.MINCARSPACE) {
                return false;
            }
        }
        return true;
    }

}