package battleship;

import java.util.Scanner;

public class Main {

public static void main(String[] args) {

// Write your code here

GameBoard gameBoard = new GameBoard();

gameBoard.initPlayers();

gameBoard.prepareShips();

gameBoard.startWar();

}

}

class Player {

public Player(String playerName) {

this.playerName = playerName;

this.shipBoard = Tools.initTheFogOfWar();

this.targetShipBoard = Tools.initTheFogOfWar();

this.ships = new Ship[DefineShip.values().length];

}

private final String playerName;

private final String[][] shipBoard;

private final String[][] targetShipBoard;

private final Ship[] ships;

private int shipCells;

private int hitCounter;

private Ship hitShip;

public String[][] getShipBoard() {

return shipBoard;

}

public String[][] getTargetShipBoard() {

return targetShipBoard;

}

public int getShipCells() {

return shipCells;

}

public int getHitCounter() {

return hitCounter;

}

public String getPlayerName() {

return playerName;

}

public void updateShipBoard(Ship ship) {

for (int i = 0; i < ship.cells(); i++) {

updateShipBoard(ship.location()[i].rowNum(), ship.location()[i].colNum(), ship.denotes()[i].toString());

}

}

private void updateShipBoard(int row, int col, String symbol) {

shipBoard[row][col] = symbol;

}

public void updateTargetShipBoard(int row, int col, String symbol) {

targetShipBoard[row][col] = symbol;

}

public void countThisShipCells(int cells) {

shipCells += cells;

}

public void collectPlayerShips(int shipIndex, Ship nextShip) {

ships[shipIndex] = nextShip;

}

public boolean hitAShoot(int[] shipLocation) {

boolean hasHitANewShip = ShipSymbol.O.name().equals(shipBoard[shipLocation[0]][shipLocation[1]]);

boolean isThatOldShip = ShipSymbol.X.name().equals(shipBoard[shipLocation[0]][shipLocation[1]]);

updateShipBoard(shipLocation[0], shipLocation[1],

hasHitANewShip || isThatOldShip ? ShipSymbol.X.name() : ShipSymbol.M.name());

if (hasHitANewShip) {

updatePlayerShip(shipLocation);

hitCounter++;

}

return hasHitANewShip || isThatOldShip;

}

public void updatePlayerShip(int[] shipLocation) {

int j = 0;

out:

for (Ship ship : ships) {

for (Location location : ship.location()) { // each location has one ship symbol

if (location.rowNum() == shipLocation[0] && location.colNum() == shipLocation[1]

&& ship.denotes()[j] == ShipSymbol.O) {

ship.denotes()[j] = ShipSymbol.X;

hitShip = ship;

break out;

}

j++;

}

j = 0;

}

}

public boolean isShipSink() {

for (int i = 0; i < hitShip.denotes().length; i++) {

if (hitShip.denotes()[i] == ShipSymbol.O) {

return false;

}

}

return true;

}

}

class Tools {

public static final String FOG = "~";

private static final String COL_HEADER = " 1 2 3 4 5 6 7 8 9 10";

private static final String C_SPACE = " ";

public static String[][] initTheFogOfWar() {

return new String[][] { { FOG, FOG, FOG, FOG, FOG, FOG, FOG, FOG, FOG, FOG },

{ FOG, FOG, FOG, FOG, FOG, FOG, FOG, FOG, FOG, FOG },

{ FOG, FOG, FOG, FOG, FOG, FOG, FOG, FOG, FOG, FOG },

{ FOG, FOG, FOG, FOG, FOG, FOG, FOG, FOG, FOG, FOG },

{ FOG, FOG, FOG, FOG, FOG, FOG, FOG, FOG, FOG, FOG },

{ FOG, FOG, FOG, FOG, FOG, FOG, FOG, FOG, FOG, FOG },

{ FOG, FOG, FOG, FOG, FOG, FOG, FOG, FOG, FOG, FOG },

{ FOG, FOG, FOG, FOG, FOG, FOG, FOG, FOG, FOG, FOG },

{ FOG, FOG, FOG, FOG, FOG, FOG, FOG, FOG, FOG, FOG },

{ FOG, FOG, FOG, FOG, FOG, FOG, FOG, FOG, FOG, FOG } };

}

public static void showFields(String[][] gameFields) {

char rowHeader = 'A';

System.out.println(COL_HEADER);

for (String[] gameField : gameFields) {

System.out.print(rowHeader++);

for (String shipOrFog : gameField) {

System.out.print(C_SPACE + shipOrFog);

}

System.out.print("\n");

}

System.out.print("\n");

}

public static Location[] buildShipLocation(int length, int[] beginEnd) {

// 0 1 0 5 -> 01 02 03 04 05

// 0 1 5 1 -> 01 11 21 31 41 51

int i0 = beginEnd[0];

int i1 = beginEnd[1];

int i2 = beginEnd[2];

int i3 = beginEnd[3];

Location[] locations = new Location[length];

for (int i = 0; i < length; i++) {

if (beginEnd[0] == beginEnd[2] && beginEnd[1] < beginEnd[3]) {

locations[i] = new Location(i0, i1++);

} else if (beginEnd[0] == beginEnd[2] && beginEnd[1] > beginEnd[3]) {

locations[i] = new Location(i0, i3++);

} else if (beginEnd[1] == beginEnd[3] && beginEnd[0] < beginEnd[2]) {

locations[i] = new Location(i0++, i1);

} else if (beginEnd[1] == beginEnd[3] && beginEnd[0] > beginEnd[2]) {

locations[i] = new Location(i2++, i1);

}

}

return locations;

}

public static ShipSymbol[] buildShipSymbols(int size) {

ShipSymbol[] s = new ShipSymbol[size];

for (int i = 0; i < size; i++) {

s[i] = ShipSymbol.O;

}

return s;

}

public static int[] getInput(String coordinate) {

try {

// split("\\s+")

int space = coordinate.indexOf(C_SPACE);

int c1 = convertTo(coordinate.charAt(0));

int c2 = Integer.parseInt(coordinate.substring(1, space)) - 1;

int c3 = convertTo(coordinate.substring(space + 1, space + 2).charAt(0));

int c4 = Integer.parseInt(coordinate.substring(space + 2)) - 1;

return new int[] { c1, c2, c3, c4 };

} catch (NumberFormatException e) {

// un-define 1A 5A

System.out.println(e.getMessage());

return new int[] {};

}

}

private static int convertTo(char c) {

int i = -1;

switch (c) {

case 'A' -> i = 0;

case 'B' -> i = 1;

case 'C' -> i = 2;

case 'D' -> i = 3;

case 'E' -> i = 4;

case 'F' -> i = 5;

case 'G' -> i = 6;

case 'H' -> i = 7;

case 'I' -> i = 8;

case 'J' -> i = 9;

}

return i;

}

public static int[] getShootLocation(String choose) {

// choose.replaceAll(regex,"");

int row = Tools.convertTo(choose.charAt(0));

int col = Integer.parseInt(choose.substring(1)) - 1;

return new int[] { row, col };

}

}

class GameBoard {

private static final int PLAYERS = 2;

private Player[] players;

private static final Scanner sc = new Scanner(System.in);

public void initPlayers() {

players = new Player[PLAYERS];

// for[0,1]

players[0] = new Player("Player 1");

players[1] = new Player("Player 2");

}

public void prepareShips() {

int[] beginEnd;

boolean isValidBeginEnd;

Ship nextShip;

Location[] locations;

ShipSymbol[] shipSymbols;

int shipIndex;

for (int i = 0; i < PLAYERS; i++) {

System.out.println(players[i].getPlayerName() + ", place your ships on the game field");

Tools.showFields(players[i].getShipBoard());

shipIndex = 0;

for (DefineShip ship : DefineShip.values()) {

System.out.println("Enter the coordinates of the " + ship.toString());

do {

isValidBeginEnd = false;

beginEnd = Tools.getInput(sc.nextLine().trim().toUpperCase());

if (beginEnd.length == 4) {

isValidBeginEnd = checkCoordinate(players[i], ship, beginEnd);

}

} while (!isValidBeginEnd);

locations = Tools.buildShipLocation(ship.getCell(), beginEnd);

shipSymbols = Tools.buildShipSymbols(ship.getCell());

nextShip = new Ship(ship.getCell(), locations, shipSymbols);

players[i].updateShipBoard(nextShip);

players[i].countThisShipCells(ship.getCell());

players[i].collectPlayerShips(shipIndex++, nextShip);

Tools.showFields(players[i].getShipBoard());

}

nextPLayer();

}

}

public void startWar() {

int index = 0;

int turn, nextTurn;

do {

turn = index % 2; // 0 1

nextTurn = turn == 0 ? 1 : 0;

Tools.showFields(players[turn].getTargetShipBoard());

System.out.println("---------------------");

Tools.showFields(players[turn].getShipBoard());

System.out.println(players[turn].getPlayerName() + ", it's your turn:");

int[] location;

do {

location = Tools.getShootLocation(sc.nextLine().trim().toUpperCase());

} while (!checkShootLocation(location));

boolean howThatShoot = players[nextTurn].hitAShoot(location); // player 1 hit player 2 or versa

if (howThatShoot) { // hit ship's other player or not?

players[turn].updateTargetShipBoard(location[0], location[1], ShipSymbol.X.name());

if (players[nextTurn].getHitCounter() == players[nextTurn].getShipCells()) {

System.out.println("You sank the last ship. You won. Congratulations!");

break; // here

} else if (players[nextTurn].isShipSink()) {

System.out.println("You sank a ship!\n");

} else {

System.out.println("You hit a ship!\n");

}

} else {

players[turn].updateTargetShipBoard(location[0], location[1], ShipSymbol.M.name());

System.out.println("You missed!");

}

index++;

nextPLayer();

} while (players[nextTurn].getHitCounter() < players[nextTurn].getShipCells());

}

private void nextPLayer() {

System.out.println("Press Enter and pass the move to another player\n...");

sc.nextLine();

}

private boolean checkShootLocation(int[] choose) {

if (choose[0] < 0 || choose[1] < 0 || choose[1] > 9) {

System.out.println("Error! You entered the wrong coordinates! Try again:");

return false;

}

return true;

}

private boolean checkCoordinate(Player player, DefineShip ship, int[] coordinate) {

int i0 = coordinate[0];

int i1 = coordinate[1];

int i2 = coordinate[2];

int i3 = coordinate[3];

// Math.abs(n);

// Math.max(a,b)

int size = i0 == i2 ? Math.abs(i3 - i1) + 1 : Math.abs(i2 - i0) + 1;

// Math.()

if (i0 < 0 || i0 > 9 || i1 < 0 || i1 > 9 || i2 < 0 || i2 > 9 || i3 < 0 || i3 > 9) {

// un-define A-1 A-5

return false;

} else if (size != ship.getCell()) {

System.out.println("Error! Wrong length of the " + ship.getShipName() + "! Try again:");

return false;

} else if (i0 != i2 && i1 != i3) { // mean 1 2 2 1, mean A2 B1

System.out.println("Error! Wrong ship location! Try again:");

return false;

} else {

Location[] newLocations = Tools.buildShipLocation(ship.getCell(), coordinate);

if (checkAround(player, newLocations)) { // has any ship around?

System.out.println("Error! You placed it too close to another one. Try again:");

return false;

}

}

return true;

}

private boolean checkAround(Player player, Location[] newLocations) {

int ySub1, xSub1, yAdd1, xAdd1, row, col;

for (Location l : newLocations) {

row = l.rowNum();

col = l.colNum();

ySub1 = Math.max(row - 1, 0);

yAdd1 = Math.min(row + 1, 9);

xSub1 = Math.max(col - 1, 0);

xAdd1 = Math.min(col + 1, 9);

// max are 8 fog around 1 point + itself check

if (!Tools.FOG.equals(player.getShipBoard()[ySub1][xSub1])

|| !Tools.FOG.equals(player.getShipBoard()[row][xSub1])

|| !Tools.FOG.equals(player.getShipBoard()[yAdd1][xSub1])

|| !Tools.FOG.equals(player.getShipBoard()[ySub1][col])

|| !Tools.FOG.equals(player.getShipBoard()[yAdd1][col])

|| !Tools.FOG.equals(player.getShipBoard()[ySub1][xAdd1])

|| !Tools.FOG.equals(player.getShipBoard()[row][xAdd1])

|| !Tools.FOG.equals(player.getShipBoard()[yAdd1][xAdd1])

|| !Tools.FOG.equals(player.getShipBoard()[row][col])) {

return true;

}

}

return false;

}

}

enum DefineShip {

AC("Aircraft Carrier", 5)

, B("Battleship", 4)

, S("Submarine", 3)

, C("Cruiser", 3)

, D("Destroyer", 2);

private final String shipName;

private final int cell;

DefineShip(String shipName, int cell) {

this.cell = cell;

this.shipName = shipName;

}

public String getShipName() {

return shipName;

}

public int getCell() {

return cell;

}

@Override

public String toString() {

return this.getShipName() + " (" + this.getCell() + " cells)";

}

}

enum ShipSymbol {

O, X, M

}

record Ship(int cells, Location[] location, ShipSymbol[] denotes) {

}

record Location(int rowNum, int colNum) {

}