Let's write a basic implementation of the classic game Battleship!

You should start with a very basic implementation. Write Battleship as a single-player game; it's you against the game. There is only one board; the computer will fill it with ships at random, and it will be your job to find and destroy these ships by guessing their coordinates.

As in previous projects, you should organize your program using multiple classes; each class should have clear responsibilities and encapsulate a distinct part of the overall game "story". I split my program into the following classes:

• A Board class with an underlying grid (a two-dimensional Array), where each element in a row represents a ship, open water, or a space that has already been attacked. I used the symbol :s to represent an undamaged ship (or ship segment), nil for empty space, and :x to represent a destroyed space. Useful Board methods:
  • Board#display: prints the board, with marks on any spaces that have been fired upon.
  • Board#count: returns the number of valid targets (ships) remaining
  • Board#populate_grid to randomly distribute ships across the board
  • Board#in_range?(pos)
• A HumanPlayer class, responsible for translating user input into positions of the form [x, y]
• A BattleshipGame class to enforce rules and run the game. The game should keep a reference to the Player, as well as the Board. Some (possibly) useful methods:
  • BattleshipGame#play: runs the game by calling play_turn until the game is over.
  • BattleshipGame#play_turn: gets a guess from the player and makes an attack.
  • BattleshipGame#attack(pos): Marks the board at pos, destroying or replacing any ship that might be there.
  • BattleshipGame#display_status: Prints information on the current state of the game, including board state and the number of ships remaining.

Note: You probably won't need a Ship class (at least, not at first). As noted above, a simple Symbol is sufficient for the basic implementation. For the bonus phase, however, you probably will want to write this class.

• Add a ComputerPlayer class that will fire at random positions on the board. Make it as smart as you can; ensure that it doesn't fire at the same position twice. You should not need to modify any logic internal to your Game class in order to support computer players.
• Refactor your game so that there are two players, each with his or her own board. Players should take turns firing at each other's fleet.
• Introduce a "setup" phase, where each player can place ships on their board.
• Update your game to use different types of ships, each of a different size. Here are the canonical ship sizes (though of course you could choose your own):