[НП] File system

import java.time.LocalDate;
import java.time.LocalDateTime;
import java.util.*;
import java.util.stream.Collectors;

/**
 * Partial exam II 2016/2017
 */
public class FileSystemTest {
    public static void main(String[] args) {
        FileSystem fileSystem = new FileSystem();
        Scanner scanner = new Scanner(System.in);
        int n = scanner.nextInt();
        scanner.nextLine();
        for (int i = 0; i < n; i++) {
            String line = scanner.nextLine();
            String[] parts = line.split(":");
            fileSystem.addFile(parts[0].charAt(0), parts[1],
                    Integer.parseInt(parts[2]),
                    LocalDateTime.of(2016, 12, 29, 0, 0, 0).minusDays(Integer.parseInt(parts[3]))
            );
        }
        int action = scanner.nextInt();
        if (action == 0) {
            scanner.nextLine();
            int size = scanner.nextInt();
            System.out.println("== Find all hidden files with size less then " + size);
            List<File> files = fileSystem.findAllHiddenFilesWithSizeLessThen(size);
            files.forEach(System.out::println);
        } else if (action == 1) {
            scanner.nextLine();
            String[] parts = scanner.nextLine().split(":");
            System.out.println("== Total size of files from folders: " + Arrays.toString(parts));
            int totalSize = fileSystem.totalSizeOfFilesFromFolders(Arrays.stream(parts)
                    .map(s -> s.charAt(0))
                    .collect(Collectors.toList()));
            System.out.println(totalSize);
        } else if (action == 2) {
            System.out.println("== Files by year");
            Map<Integer, Set<File>> byYear = fileSystem.byYear();
            byYear.keySet().stream().sorted()
                    .forEach(key -> {
                        System.out.printf("Year: %d\n", key);
                        Set<File> files = byYear.get(key);
                        files.stream()
                                .sorted()
                                .forEach(System.out::println);
                    });
        } else if (action == 3) {
            System.out.println("== Size by month and day");
            Map<String, Long> byMonthAndDay = fileSystem.sizeByMonthAndDay();
            byMonthAndDay.keySet().stream().sorted()
                    .forEach(key -> System.out.printf("%s -> %d\n", key, byMonthAndDay.get(key)));
        }
        scanner.close();
    }
}

// Your code here

class File implements Comparable<File>{
    private String name;
    private int size;
    private LocalDateTime date;

    public File(String name, int size, LocalDateTime date) {
        this.name = name;
        this.size = size;
        this.date = date;
    }

    @Override
    public int compareTo(File other){
        if(getDate().compareTo(other.getDate()) == 0){
            if(getName().compareTo(other.getName()) == 0)
                return Integer.compare(getSize(), other.getSize());
                return getName().compareTo(other.getName());
        }
        return getDate().compareTo(other.getDate());
    }

    @Override
    public String toString(){
        return String.format("%-10s %5dB %s", name, size, date);
    }

    public String getName() {
        return name;
    }


    public int getSize() {
        return size;
    }

    public LocalDateTime getDate() {
        return date;
    }

    public int getYear(){
        return date.getYear();
    }

    public String getMonthAndDay(){
        return date.getMonth() + "-" + date.getDayOfMonth();
    }
}

class FileSystem{
    Map<Character, TreeSet<File>> folders;

    FileSystem(){
        folders = new HashMap<>();
    }

    public void addFile(char folder, String name, int size, LocalDateTime createdAt){
        if(folders.containsKey(folder)){
            TreeSet<File> set = folders.computeIfAbsent(folder, f -> new TreeSet<>());
            set.add(new File(name, size, createdAt));
            return;
        }
        TreeSet<File> set = new TreeSet<>();
        set.add(new File(name, size, createdAt));
        folders.put(folder, set);
    }

    public List<File> findAllHiddenFilesWithSizeLessThen(int size){
        return
        folders.values().stream()
                .flatMap(set -> set.stream())
                .filter(folder -> folder.getName().startsWith("."))
                .filter(folder -> folder.getSize() < size)
                .collect(Collectors.toList());
    }

    public int totalSizeOfFilesFromFolders(List<Character> folders){
        return this.folders.entrySet().stream()
                .filter(entry -> folders.contains(entry.getKey()))
                .flatMap(entry -> entry.getValue().stream())
                .mapToInt(File::getSize)
                .sum();
    }

    public Map<Integer, Set<File>> byYear(){
        return folders.values().stream()
                .flatMap(folder -> folder.stream())
                .collect(Collectors.groupingBy(File::getYear, Collectors.toSet()));
    }

    public Map<String, Long> sizeByMonthAndDay(){
        return folders.values().stream()
                .flatMap(folder -> folder.stream())
                .collect(Collectors.groupingBy(File::getMonthAndDay, Collectors.summingLong(File::getSize)));
    }
}