Chess

A Python chess game where you can play against a bot that matches your skill level adaptively.

Game, bot, and website all developed by ishsharm0 and rosharma719.

Overview

• gameLogic.py — Generates legal moves, including castling, en passant, and promotion, and removes moves that leave the king in check.
• bot.py — Evaluates positions using material plus piece-square tables to account for piece placement.

The engine searches using negamax with alpha–beta pruning, exploring several plies while cutting off branches that cannot improve the result. A quiescence search extends evaluation in tactical positions (mainly captures) to avoid unstable leaf evaluations.

Terminal states are handled explicitly: if a side has no legal moves, the engine distinguishes checkmate from stalemate.

Adaptive Difficulty

The web app adjusts difficulty dynamically:

• After each player move, the system compares it with the engine’s stronger candidate line using evaluate_move_quality.
• A running error estimate is tracked during the session.
• The bot’s search depth is increased or decreased accordingly, producing stronger replies for stronger play and faster replies for weaker play.

Setup + Running Locally

Prerequisites:

• Python 3.8+
• Git

Run these commands in a directory of your choice (Windows/MacOS/Linux):

git clone https://github.com/starryxvii/chess.git
cd chess
pip install -r requirements.txt
echo SECRET_KEY=MySecretKey > .env
python app.py

To play the game in your console, simply run python consoleMode.py instead of python app.py.

Optional Engine Testing

This repo includes a minimal UCI wrapper (uci.py) so you can play games against other engines like Stockfish.

• Run a direct OurBot vs Stockfish match (prints moves live):
  • python match_runner.py --black stockfish --movetime-ms 30000 --pgnout matches.pgn
• Run move-generation correctness checks (perft):
  • python perft.py startpos 4