package OO14route66;

import com.camilstaps.route66.Crossing;
import java.util.ArrayList;
import java.util.Observable;
import java.util.logging.Level;
import java.util.logging.Logger;
import javax.swing.JFrame;

/**
 * OO1route66 initial class
 * @author Pieter Koopman
 *
 * The class model holds all cars in the simulation
 */
public class Model extends Observable
{
    private final Car [] cars;
    public static final int
        DIRECTIONS = 4,
        NUMBEROFCARS = 5 * DIRECTIONS;   // total number of cars in system
        
    private final ArrayList<JFrame> views;
    private final Crossing crossing = new Crossing(this, Direction.North);

    /**
     * Constructor: create all cars
     */
    public Model() {
        views = new ArrayList<>();
        cars = new Car [NUMBEROFCARS];
        for (int c = 0; c < NUMBEROFCARS; c += 1) {
            cars[c] = new Car(c, this);
        }
    }
    
    /**
     * add the view to this model. It will be repainted upon an update
     * @param view 
     */
    public void addView(JFrame view) {
        views.add(view);
    }
    
    public Car[] getCars() {
        return cars;
    }

    /**
     * get a car from the model
     * @param i numbers of required car
     * @return the car itself (not a copy)
     */
    public Car getCar(int i) {
        return cars[i];
    }
    
    /**
     * repaint all views
     */
    public synchronized void update() {
        for (JFrame view: views) {
            view.repaint();
        }
        notifyAll();
    }
    
    /**
     * Check if a location is safe for a car to go to. This should always be 
     * checked by a driver before actually driving.
     * @param car
     * @param requested_location
     * @return 
     */
    public synchronized boolean isSafeLocation(Car car, int requested_location) {
        Car that_car = cars[car.getNumber() < DIRECTIONS ? car.getNumber() + NUMBEROFCARS - DIRECTIONS : car.getNumber() - DIRECTIONS];
        
        boolean ok;
        
        System.err.println("Car " + car.getNumber() + " requests safety.");
        
        do {
            ok = !(that_car.getLocation() > requested_location &&
                    that_car.getLocation() < requested_location + Car.CARLENGTH + Car.MINCARSPACE);

//            if (!ok && that_car.getDriver().getWaitingToCross()) {
//                crossing.doRequest();
//            }
            
            if (car.isInFrontOfCrossing() && !crossing.isAllowed(car.getDirection())) {
                System.err.println("Requesting switch for car " + car.getNumber());
                ok = false;
                //if (!car.getDriver().getWaitingToCross()) {
                    //car.getDriver().setWaitingToCross(true);
                    ok = crossing.doRequest();
                    //car.getDriver().setWaitingToCross(!ok);
                //}
            }
            
            if (!ok) {
                System.err.println("Car " + car.getNumber() + " waiting.");
                try {
                    wait();
                } catch (InterruptedException ex) {
                }
                System.err.println("Car " + car.getNumber() + " acquired lock.");
            }
        } while (!ok);
        
        System.err.println("Car " + car.getNumber() + " has safe location.");
        
        return ok;
    }
    
    public synchronized boolean isNoCarsOnCrossing() {
        boolean ok = false;
        while (!ok) {
            ok = true;
            for (Car car : cars) {
                if (car.isOnCrossing()) {
                    System.err.println("Car " + car.getNumber() + " is on crossing.");
                    ok = false;
                }
            }
            if (!ok) {
                System.err.println("Checking crossing waiting");
                try {
                    wait();
                } catch (InterruptedException ex) {
                }
                System.err.println("Checking crossing");
            }
        }
        return true;
    }
}