import java.util.concurrent.CyclicBarrier;
import java.util.concurrent.BrokenBarrierException;
import java.util.concurrent.CountDownLatch;
import java.util.Random;

class SiHei implements Runnable{
    CyclicBarrier barriere;
    int speed;
    int nr;

    SiHei(CyclicBarrier b, int speed, int nr){
        this.speed = speed;
        this.nr = nr;
        barriere = b;
    }

    public void run() {
        for (int i =0; i<4; i++){
            try {
                Thread.currentThread().sleep(speed);
            } catch(Exception e) {
                System.out.println(e);
            }

            System.out.println("hei fra traad nr " + nr + "...");

            try {
                barriere.await();
            } catch(InterruptedException e) {
                System.out.println(e);
            } catch (BrokenBarrierException e){
                System.out.println(e);
            }
        }
    }
}

class Loper implements Runnable{
    Random r;
    CountDownLatch maal;
    int lopsNummer;
    int etapper;

    Loper(Random r, int etapper, int lopsNummer, CountDownLatch maal){
        this.r = r;
        this.etapper = etapper;
        this.lopsNummer = lopsNummer;
        this.maal = maal;
    }

    public void run(){
        int lopt = 0;
        int etappeTid;
        int totalTid = 0;
        while (lopt<etapper){
            lopt++;
            etappeTid = r.nextInt(800);
            totalTid += etappeTid;
            try {
                Thread.currentThread().sleep(etappeTid);
            } catch(Exception e) {
                System.out.println(e);
            }
        }
        System.out.println("Løper nummer "+lopsNummer+" kom i mål!");
        try {
            maal.countDown();
            maal.await();
        } catch(Exception e) {
            System.out.println(e);
        }
        System.out.println("Løper "+lopsNummer+" kom i mål på " +totalTid);
    }
}



class TestBarrierer {
    public static void main(String[] args){


        System.out.println("Starter noe cyclical bussiness..");

        Random r = new Random();
        CyclicBarrier barriere = new CyclicBarrier(5, new Runnable(){
            public void run(){
                System.out.println("Nå har 5 tråder sagt hei!");
            }
        });

        for (int i = 0; i<5; i++){
            new Thread(new SiHei(barriere, r.nextInt(1000), (i+1))).start();
        }

        try {
            Thread.currentThread().sleep(4000);
        } catch(Exception e) {
            System.out.println(e);
        }


        System.out.println("\n\nStarter noe countdown stuff...\n");

        CountDownLatch countDown = new CountDownLatch(5);

        for (int i = 0; i<5; i++){
            System.out.println("Starten går for løper nr " + (i+1));
            new Thread(new Loper(r, 5, i+1, countDown)).start();
        }
        System.out.println("Main kunne sluttet nå!");
        try {
            countDown.await();
        } catch(InterruptedException e) {
            System.out.println(e);
        }
        System.out.println("Nå er main ferdig.");
    }
}