Tic-tac-toe-minimax NPM

Tic-Tac-Toe Minimax AI Module

Module that given a tic-tac-toe board determines the AI's move and/or returns next state board based on the given board. It has three level of AI's difficulty. Note: Only tested on a 3x3 board

Difficulty	Description
Easy	AI's move is decided solely based on Math.random()
Hard	AI's move is decided through the minimax algorithm
Normal	AI's move has 50/50 chance to be a "Hard difficulty" move or a "Easy difficulty" move

DEMO

Modules

ComputerMove

const nextMove = ComputerMove( board, symbols, difficulty );      //returns a Number

This module computes the best move to be made by the computer.

Inputs	Description
symbols	Object with huPlayer and aiPlayer symbol.
board	Array representing the board. Empty squares should have the value of the index numer in the respective element.
difficulty	"Easy"\|"Normal"\|"Hard"

Example:

import Minimax from 'tic-tac-toe-minimax'
const { ComputerMove } = Minimax;

const huPlayer = "X";
const aiPlayer = "O";
const symbols = {
    huPlayer: huPlayer,
    aiPlayer: aiPlayer
}
const difficulty = "Hard";
const board = [0,1,aiPlayer,3,huPlayer,huPlayer,6,7,8];

const nextMove = ComputerMove( board, symbols, difficulty );        //returns 3

GameStep

This module wraps the ComputerMove module and calculates the "next" board. If a final game condition in reached it will be informed through the winner property. Also, if a final condition is met the board will remain the same.

const gameState = GameStep(board, symbols, difficulty);      //returns an Object
/*
returns {
    winner: ("huPlayer" | "aiPlayer" | "draw" | null),
    board: Array
}
*/

If the provided board has both winning conditions (both player and AI won somehow), the winner will be the player.

Example:

import Minimax from 'tic-tac-toe-minimax'
const { GameStep } = Minimax;

const huPlayer = "X";
const aiPlayer = "O";
const symbols = {
    huPlayer: huPlayer,
    aiPlayer: aiPlayer
}
const difficulty = "Hard";
const board = [0,1,aiPlayer,3,huPlayer,huPlayer,6,7,8];

const gameStep = GameStep( board, symbols, difficulty );
/*
returns {
    winner: null,
    board: [0,1,aiPlayer,aiPlayer,huPlayer,huPlayer,6,7,8]
}
*/