import java.util.*;

public class Movie {
    private long id;
    private String title;
    private Date releaseDate;
    private HashSet<String> category;
    private Integer budget;
    private Rating rating;

    public long getId() {
        return id;
    }

    public String getTitle() {
        return title;
    }

    public Date getReleaseDate() {
        return releaseDate;
    }

    public HashSet<String> getCategory() {
        return category;
    }

    public Integer getBudget() {
        if (budget == null)
            return budget;
        else
            return 0;
    }

    public Integer getIncome() {
        if (income == null)
            return income;
        else
            return 0;
    }

    private Integer income;

    public double getProfit() {
        return income - budget;
    }

    public static final HashSet<String> knownCategories = new HashSet<String>() {{ add("horror"); add("comedy"); add("scifi"); }};

    private static ArrayList<Movie> movies = new ArrayList<Movie>();

    public static ArrayList<Movie> findByCategory(String cat) {
        ArrayList<Movie> movies = new ArrayList<Movie>();
        for (Movie movie : Movie.movies) {
            if (movie.getCategory().contains(cat))
                movies.add(movie);
        }
        return movies;
    }

    public static ArrayList<Movie> findByRating(Rating rating) {
        ArrayList<Movie> movies = new ArrayList<Movie>();
        for (Movie movie : Movie.movies) {
            if (movie.rating == rating)
                movies.add(movie);
        }
        return movies;
    }

    public Movie(long id, String title, Date releaseDate, HashSet<String> category, Integer budget, Rating rating, Integer income) {
        if (category.isEmpty()) {
            throw new IllegalArgumentException("categories cant be emppty");
        }


        this.id = id;
        this.title = title;
        this.releaseDate = releaseDate;
        this.category = new HashSet<String>();
        for (String cat : category) {
            if (knownCategories.contains(cat)) {
                this.category.add(cat);
            }
        }
        this.budget = budget;
        this.rating = rating;
        this.income = income;

        movies.add(this);
    }
}


import java.util.Date;
import java.util.HashSet;

public class Main {

    public static void main(String[] args) {

        System.out.println("Hello World!¬");
        Movie dramat = new Movie(1, "smolensk", new Date(), new HashSet<String>(){{add("drama");}}, 100, Rating._7, 500);
        Movie dramat2 = new Movie(1, "smolensk 2", new Date(), new HashSet<String>(){{add("drama"); add("horror");}}, 500, Rating._12, 500);
        Movie horror = new Movie(1, "maczeta", new Date(), new HashSet<String>(){{add("horror");}}, 500, Rating.AL, 500);

        System.out.println(Movie.findByCategory("horror"));
        System.out.println(Movie.findByCategory("drama"));
        System.out.println(Movie.findByRating(Rating._7));
        System.out.println(dramat.getProfit());
    }
}


public enum Rating {
    AL, _7, _12, _15, _21
}