import java.util.Scanner;

public class Seabatle {
    //Len. of gamefield. Ships count. Min-max size range.
    static final int SIZE = 20, COUNT_SHIP = 3, MIN_SIZE_SHIP = 1, MAX_SIZE_SHIP = 3;
    static final char LIVE = 'X', DEAD = '#', MISS = '*', EMPTY = '.';
    static char[] cells = new char[SIZE];

    public static void main(String[] args) {
        doGame();
    }

    private static void doGame() {
        initField();
        createShips();
        mainGameCycle();
    }

    private static void mainGameCycle() {
        Scanner scanner = new Scanner(System.in);
        do {
            showGameField();
            int shoot = userMakeShoot(scanner);
            switch (cells[shoot]) {
                case EMPTY:
                    System.out.println("Промах");
                    cells[shoot] = MISS;
                    break;
                case LIVE:
                    System.out.println("Попадание");
                    cells[shoot] = DEAD;
                    break;
                case DEAD: // Нет оповещения о потоплении корабля
                case MISS:
                    System.out.println("Повторный выстрел");
                    break;
            }
        } while (!isAllShipsSunk());
        showGameField();
        System.out.println("Игра окончена");
    }

    private static void initField() {
        for (int i = 0; i < SIZE; i++) {  //Init field
            cells[i] = EMPTY;
        }
    }

    private static void createShips() {
        int part = SIZE / COUNT_SHIP;             //Partition field for one ship
        for (int i = 0; i < COUNT_SHIP; i++) {
            int sizeShipRandom = (int) (Math.random() * (MAX_SIZE_SHIP - 1)) + MIN_SIZE_SHIP;
            int positionShipRandom = (int) (Math.random() * (part - sizeShipRandom) + (part * i + i));
            for (int j = positionShipRandom; j <= sizeShipRandom + positionShipRandom; j++) {
                cells[j] = LIVE;
            }
        }
    }

    private static void showGameField() {
        for (int i = 0; i < SIZE; i++) {
            char cell = cells[i] == LIVE ? EMPTY : cells[i];
            System.out.print(cell);
        }
        System.out.print("\n");
    }

    private static int userMakeShoot(Scanner scanner) {
        //Не уверен что правильно с передачей параметров но делать scanner и shoot глобальными не хотелось
        int shoot = -1;

        do {
            System.out.println("Введите координату для выстрела число от 0 до 19");
            if (scanner.hasNextInt()) {
                shoot = scanner.nextInt();
                scanner.nextLine();
                if ((shoot >= 0)&&(shoot < SIZE)) break;
            } else {
                scanner.nextLine();
            }
            System.out.println("Ввод неверный");
        } while (true);
        System.out.println("Вы ввели " + shoot);
        return shoot;
    }

    private static boolean isAllShipsSunk() {
        boolean allShipsSunk = true;
        for (int i = 0; i < SIZE; i++) {
            allShipsSunk &= cells[i] != LIVE;
        }
        return allShipsSunk;
    }
}