♜ @mady9613/chess-engine

A complete chess engine with move validation, FEN support, and utilities

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---# @mady9613/chess-engine

Comprehensive chess engine for move validation and game state management.

• npm: https://www.npmjs.com/package/@mady9613/chess-engine
• Author: mady9613

Installation

npm install @mady9613/chess-engine

Quick Start

import { ChessGame } from '@mady9613/chess-engine';

const game = new ChessGame();

const move = game.move('e2e4');
console.log(move.success); // true
console.log(move.san);     // "e4"
console.log(game.getFEN()); // Current FEN

Main Class: ChessGame

Create game

const game = new ChessGame();           // start position
const gameFromFen = new ChessGame(fen); // from FEN

Common methods

• move(move, promotionPiece?)
• undo(), redo(), canUndo(), canRedo()
• reset()
• loadFEN(fen), getFEN()
• loadPGN(pgn), getPGN()
• getBoard(), getPieceAt(square), getTurn()
• getValidMoves(square), getAllValidMoves()
• isValidMove(move)
• isCheck(), isCheckmate(), isStalemate(), isDraw(), isGameOver()
• isThreefoldRepetition(), isFiftyMoveRule(), isInsufficientMaterial()
• getWinner(), getResult()
• getMoveHistory(), getMoves(), getLastMove(), getMoveCount()
• goToMove(index), goToStart(), goToEnd()
• toJSON(), toObject(), clone(), fromJSON(data)

Static utility

• ChessGame.isValidFEN(fen)

Move Input Format

Supported move input styles:

• UCI-like string: "e2e4", "e7e8q"
• Object format: { from: 'e2', to: 'e4' }
• Object with promotion: { from: 'e7', to: 'e8', promotion: 'q' }

Promotion pieces: q, r, b, n

Move Result Shape

game.move(...) returns:

{
  success: true,
  san: 'e4',
  piece: 'wp',
  capture: false,
  check: false,
  checkmate: false,
  stalemate: false,
  promotion: null
}

If invalid:

{ success: false, error: 'Illegal move' }

Named Exports

The package also exposes lower-level helpers from src/index.js.

Validators

• getValidMoves
• getAllLegalMoves
• isMoveLegal
• isMoveLegalBasic
• isMoveLegalQuick

Piece move generators

• getPawnMoves
• getKnightMoves
• getBishopMoves
• getRookMoves
• getQueenMoves
• getKingMoves

Board / notation / FEN utilities

• getInitialBoardPosition
• getEmptyBoard
• copyBoard
• algebraicToCoord
• coordToAlgebraic
• isValidCoord
• getPieceAt
• isSquareAttacked
• doesPieceAttackSquare
• getSAN
• getDetailedSAN
• parseSAN
• boardToFEN
• FENToBoard
• getStartingFEN
• isValidFEN

Core move helpers

• executeMove
• isCaptureMove
• isPromotionMove
• getMoveSAN

Example: Validate & Play Loop

import { ChessGame } from '@mady9613/chess-engine';

const game = new ChessGame();
const moves = ['e2e4', 'e7e5', 'g1f3', 'b8c6'];

for (const m of moves) {
  const result = game.move(m);
  if (!result.success) {
    console.log('Invalid:', result.error);
    break;
  }
  console.log(result.san, game.getFEN());
}

License

MIT