Requirements

1. User Interface:
   • The game should have a graphical user interface (GUI) that represents the chessboard and the pieces.
   • Players should be able to join as either "White" or "Black".
2. Game Logic:
   • The system must enforce the rules of chess, including legal moves for each piece, check, checkmate, and stalemate conditions.
   • Players should be able to take turns making moves.
3. Game State Management:
   • The game state should keep track of the current position of pieces, captured pieces, and whose turn it is.
   • The ability to save and resume games.
4. User Accounts:
   • Optionally, register and manage user accounts for tracking wins/losses.
5. Multiplayer Support:
   • The game should be able to support two players playing against each other, either locally or over a network.
6. Timer:
   • Optionally, implement a timer to limit the time each player can take for their moves.

Core Objects & Relationships

Define Core Objects

From the requirements, the core objects for the chess system are:

1. Game: Orchestrates the entire game lifecycle.
2. Player: Represents the two participants in the game.
3. Board: Represents the 8x8 grid with squares and pieces.
4. Cell: Represents each square.
5. Piece: Represents chess pieces (King, Queen, Rook, Bishop, Knight, Pawn).
6. Square: Represents individual squares on the chessboard.

APIs & Class Members

Analyze Relationships

• Game and Player: The Game object will manage two Player objects, alternating turns between them.
• Game and Board: The Game will initialize and interact with the Board object for state updates.
• Board and Piece: The Board will contain pieces placed on Square objects.
• Piece and Move: Each Piece will validate its specific movement logic through a Move object.
• Player and Piece: Each Player will control a set of pieces (White or Black).

Establish Hierarchy

To promote code reuse, the chess pieces will inherit from a common base class:

Piece (Abstract Class): Contains common attributes like position and color.

• King
• Queen
• Rook
• Bishop
• Knight
• Pawn

Deep Dive

SOLID Guidelines

• Single Responsibility: Each class has a single purpose (e.g., Game manages gameplay, Board manages the grid).
• Open/Closed: Classes can be extended for new functionality (e.g., adding AI) without modifying existing code.
• Liskov Substitution: Derived classes (King, Queen, etc.) can replace the base class (Piece) without breaking functionality.
• Interface Segregation: Methods are well-defined and specific to their roles.
• Dependency Inversion: High-level modules like Game depend on abstractions like Piece and not concrete implementations.