Description

This project allows the user to play a game of Battleship against the computer. It was implemented in Haskell and runs on a CLI.

Setup

1. Download and install GHC/GHCI from the official downloads page (https://www.haskell.org/downloads/);

2. Type "ghci" on a terminal window, followed by ":l Main.hs";

3. Type "main" to launch the game;

4. Follow the game's instructions and have fun!

Code structure

Main.hs: contains the function responsible for actually playing the game;
AuxFunctions.hs: contains a plethora of pure and impure functions that are needed throughout the game;
GameMoves.hs: contains the functions responsible for placing the player's and computer's ships, as well as, registering their attacking moves;
GamePrints.hs: contains the functions that print the game's interface (messages, information screens, etc...);
Board.hs: contains the type definitions and instance of Show for the type BoardF;
Constants.hs: contains the game's settings (board size, ship lengths, etc...)
GameState.hs: contains some records for the state of the game, as well as, an instance of Show for the record GameState.

Implementation details

The Board

The game makes use of a record where we have offense and defense boards for both the player and the computer. In the defense boards, each player has its ships and the markings corresponding to the attacking attempts from the opposing player. These markings are:

` for a Ship;
x for a Hit;
o for a Miss;
* for a Sunken Ship.

As for the offense boards, they comprise the guesses made by each player, obviously not knowing where the opposing ships are located.

For each board (represented by the Board data record), we have a function that maps each coordinate (Coord) to a position state (PositionState) and a list of lists with the coordinates of every ship that belongs to the board/player in question.

The Players

Both players go through the process of distributing the ships in their respective boards. The computer does so automatically (either randomly or wisely - this behaviour can be configured with the boolean wiseComputer in Constants.hs), while the player is asked to enter coordinates for every ship in the following format:

startCoord;endCoord
e.g. (0,0);(0,4) - for a ship of size 5

Once the ships are in place, the game starts with each player attacking in turns.

As a side note, at any point, the player can press q to leave the game immediately.

The Game

The player will be able to see both boards (defense and offense) like in a traditional Battleship game:

o--------------------------------------------------------o
|                          PLAY                          |
o--------------------------------------------------------o

	    Player's Offense Board

     0   1   2   3   4   5   6   7   8   9
   +---+---+---+---+---+---+---+---+---+---+
0  |   |   |   |   |   |   |   |   |   |   |
   +---+---+---+---+---+---+---+---+---+---+
1  |   |   |   |   |   |   |   |   |   |   |
   +---+---+---+---+---+---+---+---+---+---+
2  |   |   |   |   |   |   |   |   |   |   |
   +---+---+---+---+---+---+---+---+---+---+
3  |   |   |   |   |   |   |   |   |   |   |
   +---+---+---+---+---+---+---+---+---+---+
4  |   |   |   |   |   |   |   |   |   |   |
   +---+---+---+---+---+---+---+---+---+---+
5  |   |   |   |   |   |   |   |   |   |   |
   +---+---+---+---+---+---+---+---+---+---+
6  |   |   |   |   |   |   |   |   |   |   |
   +---+---+---+---+---+---+---+---+---+---+
7  |   |   |   |   |   |   |   |   |   |   |
   +---+---+---+---+---+---+---+---+---+---+
8  |   |   |   |   |   |   |   |   |   |   |
   +---+---+---+---+---+---+---+---+---+---+
9  |   |   |   |   |   |   |   |   |   |   |
   +---+---+---+---+---+---+---+---+---+---+

	    Player's Defense Board

     0   1   2   3   4   5   6   7   8   9
   +---+---+---+---+---+---+---+---+---+---+
0  |   |   |   |   |   |   |   | ` |   |   |
   +---+---+---+---+---+---+---+---+---+---+
1  |   | ` | ` | ` | ` | ` |   | ` |   |   |
   +---+---+---+---+---+---+---+---+---+---+
2  | ` |   | ` | ` | ` | ` |   |   |   |   |
   +---+---+---+---+---+---+---+---+---+---+
3  | ` |   | ` |   |   |   |   | ` | ` | ` |
   +---+---+---+---+---+---+---+---+---+---+
4  |   |   | ` |   |   |   |   |   |   |   |
   +---+---+---+---+---+---+---+---+---+---+
5  |   |   | ` |   | ` |   |   |   |   |   |
   +---+---+---+---+---+---+---+---+---+---+
6  |   |   |   |   | ` |   |   |   |   | ` |
   +---+---+---+---+---+---+---+---+---+---+
7  |   |   |   |   | ` |   |   |   |   | ` |
   +---+---+---+---+---+---+---+---+---+---+
8  |   |   |   |   |   | ` | ` |   |   | ` |
   +---+---+---+---+---+---+---+---+---+---+
9  |   | ` | ` |   |   |   |   |   |   | ` |
   +---+---+---+---+---+---+---+---+---+---+

(Player) Attack position >

From this point forward, both players will enter coordinates in the familiar format (i.e. (line,column)) and wait for the program to state the outcomes, like so:

o--------------------------------------------------------o
|                       ROUND INFO                       |
o--------------------------------------------------------o
| (Player) Coordinate (1,1) was a MISS!                  |
| (Computer) Coordinate (4,7) was a HIT!                 |
o--------------------------------------------------------o

Eventually, the game will come to an end with a message indicating the winner (or winners, in case of a tie). Then, the coordinates of every ship will be revealed:

o--------------------------------------------------------o
|                       GAME OVER                        |
o--------------------------------------------------------o
| The player has won the game!				 |
o--------------------------------------------------------o

Side Note

If needed, the code can be modified to put 2 computers against each other. To do so, one can uncomment every line within a BEGIN TEST VERSION ... END TEST VERSION block and, conversely, comment every line within a BEGIN FINAL VERSION ... END FINAL VERSION block.

These blocks can be found in:

Main.hs;
GameMoves.hs;
GameState.hs.

ojoaobrito / Battleship