Chess

This repository contains the Java implementation of a complete running version of the chess game developed for the Software Development Methods course (a.y. 2024/2025).

The project provides both the core game logic (rules, movement, validation, win conditions) and a graphical user interface (GUI) that allows two players to play against each other in a timed setting.

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📖 Game Overview

Chess is a two-player strategic board game played on an 8×8 grid, the chessboard. Each player commands 16 pieces of either white or black, and the objective is to checkmate the opponent's king.

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♟️ Chessboard Layout

• Size: 8×8 grid (64 squares total)
• Colors: Alternating light and dark squares
• Notation:
  • Columns are called Files, labeled A–H (left to right from White’s perspective).
  • Rows are called Ranks, labeled 1–8 (bottom to top from White’s perspective).

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👥 Players and Pieces

Each player controls 16 pieces at the start of the game:

• Pawns (×8)
• Rooks (×2)
• Knights (×2)
• Bishops (×2)
• Queen (×1)
• King (×1)

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🔹 Initial Setup

Piece	Initial Position (White)	Initial Position (Black)
Pawns	A2–H2	A7–H7
Rooks	A1, H1	A8, H8
Knights	B1, G1	B8, G8
Bishops	C1, F1	C8, F8
Queen	D1	D8
King	E1	E8

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📊 Piece Values

While the king cannot be assigned a numeric value (since its capture ends the game), conventional chess assigns approximate point values to pieces for evaluation:

• Pawn: 1
• Knight: 3
• Bishop: 3
• Rook: 5
• Queen: 9
• King: ∞ (priceless)

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🔄 Movement and Capturing Rules

General Rules

• Moves must remain within the 8×8 chessboard.
• A piece cannot move to a square occupied by another piece of the same color.
• With the exception of the knight, pieces cannot move through other pieces.
• Capturing occurs by replacing an opponent’s piece on its square.

Piece Movements

• Pawn:
  • Moves forward 1 square, or 2 squares forward from its starting position.
  • Captures diagonally forward by 1 square.
• Rook:
  • Moves any number of squares horizontally or vertically.
• Knight:
  • Moves in an “L” shape: 2 squares in one direction, then 1 square perpendicular.
  • Can jump over other pieces.
• Bishop:
  • Moves any number of squares diagonally.
• Queen:
  • Moves any number of squares in any direction (horizontal, vertical, diagonal).
• King:
  • Moves 1 square in any direction.

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⭐ Special Moves

In addition to standard movement, chess includes special moves with specific conditions. This implementation currently supports:

1. Promotion

• When: If a pawn reaches the last rank (rank 8 for White, rank 1 for Black).
• How: It must be promoted to another piece.
• Implementation: Currently, promotion is always to a Queen (automatic queen promotion).
• Example: If a White pawn moves from E7 → E8, it becomes a White Queen.

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2. Castling

• When: A special king + rook move performed under these conditions:

  • Neither the king nor the rook involved has moved previously.
  • The squares between the king and rook are unoccupied.
  • The king is not currently in check.
  • The king cannot move through or end up in a square that is under attack.

• How:

  • The king moves two squares towards the rook.
  • The rook moves to the square immediately on the opposite side of the king.

• Types:

  • Kingside castling (short castling): King from E1 → G1 and rook from H1 → F1 (for White).
  • Queenside castling (long castling): King from E1 → C1 and rook from A1 → D1 (for White).
  • The same applies symmetrically for Black.

• Example: White king on E1 and rook on H1, with squares F1 and G1 empty and not attacked → White can castle kingside.

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3. En Passant

• When: If a pawn advances two squares forward from its starting position and passes through a square that could have been attacked by an opposing pawn.

• How: The opposing pawn may capture it as if it had only moved one square forward.

• Condition: This move must be made immediately on the following turn, otherwise the opportunity is lost.

• Example:

  • Black pawn on D4.
  • White pawn moves from E2 → E4.
  • On the next move, Black can capture the White pawn en passant by moving D4 → E3.

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🖥️ Graphical User Interface (GUI) & Game Flow

The project includes a fully interactive Java Swing GUI designed for an intuitive game experience.

Game Orientation

• The board is always oriented with White at the bottom.
• The game always starts with White’s turn.

Turn & Move Handling

• Players alternate turns, with White moving first.
• Each player has 5 minutes total to make their moves (countdown timer).
• To make a move:
  1. The current player selects a piece.
  2. The GUI highlights all legal destination squares.
  3. The player selects one of the highlighted squares to move the piece.

Toolbar Features

• Restart Game: Reset the board to the initial setup.
• Undo Last Move: Revert the most recent move.
• Exit: Quit the application.

Winning Conditions

• A player wins by:

  • Checkmate (opponent’s king is trapped), or
  • Timeout (opponent’s clock reaches zero).

• By default, after a win the game automatically restarts.

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