Makruk JS

Makruk (Thai chess) library written in Typescript

Initialize state

import { State, importFen, INITIAL_FEN } from '@kaisukez/makruk-js'
const state: State = importFen(INITIAL_FEN)

Move

There're 2 different ways to move

import {
	State,
	MoveObject,
	move,
	generateLegalMoves,
} from '@kaisukez/makruk-js'

// 1. Use Standard Algebraic Notation (SAN)
const newState: State = move(state, 'Me2')

// 2. Choose from legal moves
const moves: MoveObject[] = generateLegalMoves(state)
const newState: State = move(state, moves[0])

Check if game over

import { gameOver } from '@kaisukez/makruk-js'
const end: boolean = gameOver(state)

Simple AI (Minimax with Alpha-beta pruning technique)

import {
	State,
	importFen,
	INITIAL_FEN,
	move,
	gameOver,
	findBestMove,
	ascii,
} from '@kaisukez/makruk-js'

function runUntilGameFinished(state?: State) {
	state = state || importFen(INITIAL_FEN)
	while(!gameOver(state)) {
		const { bestMove } = findBestMove(state, 3)
		if (!bestMove) { // there's no best move, it means you're already lost
			break
		}
		state = move(state, bestMove!)
		console.log(ascii(state.boardState))
	}
	console.log('game over!')
}

runUntilGameFinished()

     +------------------------+
 8 | r  m  t  e  k  t  m  r |
 7 | .  .  .  .  .  .  .  . |
 6 | b  b  b  b  b  b  b  b |
 5 | .  .  .  .  .  .  .  . |
 4 | .  .  .  .  .  .  .  . |
 3 | B  B  B  B  B  B  B  B |
 2 | .  .  .  .  M  .  .  . |
 1 | R  M  T  K  E  T  .  R |
     +------------------------+
     a  b  c  d  e  f  g  h

     +------------------------+
 8 | r  m  t  e  k  t  m  r |
 7 | .  .  .  .  .  .  .  . |
 6 | b  b  .  b  b  b  b  b |
 5 | .  .  b  .  .  .  .  . |
 4 | .  .  .  .  .  .  .  . |
 3 | B  B  B  B  B  B  B  B |
 2 | .  .  .  .  M  .  .  . |
 1 | R  M  T  K  E  T  .  R |
     +------------------------+
     a  b  c  d  e  f  g  h

     +------------------------+
 8 | r  m  t  e  k  t  m  r |
 7 | .  .  .  .  .  .  .  . |
 6 | b  b  .  b  b  b  b  b 
 5 | .  .  b  .  .  .  .  . |
 4 | .  .  .  .  .  M  .  . |
 3 | B  B  B  B  B  B  B  B |
 2 | .  .  .  .  .  .  .  . |
 1 | R  M  T  K  E  T  .  R |
     +------------------------+
     a  b  c  d  e  f  g  h

     +------------------------+
 8 | r  m  t  e  .  t  m  r |
 7 | .  .  .  .  .  k  .  . |
 6 | b  b  .  b  b  b  b  b |
 5 | .  .  b  .  .  .  .  . |
 4 | .  .  .  .  .  M  .  . |
 3 | B  B  B  B  B  B  B  B |
 2 | .  .  .  .  .  .  .  . |
 1 | R  M  T  K  E  T  .  R |
     +------------------------+
     a  b  c  d  e  f  g  h

     +------------------------+
 8 | r  m  t  e  .  t  m  r |
 7 | .  .  .  .  .  k  .  . |
 6 | b  b  .  b  b  b  b  b |
 5 | .  .  b  .  .  .  .  . |
 4 | .  .  .  .  .  M  .  . |
 3 | B  B  B  B  B  B  B  B |
 2 | .  .  .  M  .  .  .  . |
 1 | R  .  T  K  E  T  .  R |
     +------------------------+
     a  b  c  d  e  f  g  h

Symbol

• Capital letter = White pieces (move first)
• Lowercase letter = black pieces

Symbol	Piece (English)	Piece (Thai)
B / b	Bia	เบี้ยคว่ำ
F / f	Flipped Bia	เบี้ยหงาย
R / r	Rua	เรือ
M / m	Ma	ม้า
T / t	Thon	โคน
K / k	Khun	ขุน
E / e	Met	เม็ด

Todos

• attacked (its name was changed to canThisColorAttackThisSquare) function
• inCheck / inCheckmate / inStalemate / inThreefoldRepetition
• insufficientMaterial (half finished but it's ok for now)
• functional programming utility function like "compose" ...
• refactor code
• replace Ramda with regular js (because it make code hard to read and add friction in development process)
• counting rules
• import / export FEN
• import / export PGN
• write test (Why write test last? I don't know. I'm not familiar with TDD or any kind of tests so I will put it last to be more focused on chess algorithm.)
• write documentation
• release version 0.1.0 to npm
• decide what to do next. Maybe optimize existing code or rewrite entire library using bitboard.