Qi.js

Qi (棋) is an abstraction for initializing and updating positions of chess variants (including Chess, Janggi, Markruk, Shogi, Xiangqi).

Installation

npm install @sashite/qi

Usage

Let's replay The Shortest Possible Game of Shogi:

const Qi = require('./index');

var startingPosition = new Qi(
  [],
  {
     0: "l",
     1: "n",
     2: "s",
     3: "g",
     4: "k",
     5: "g",
     6: "s",
     7: "n",
     8: "l",
    10: "r",
    16: "b",
    18: "p",
    19: "p",
    20: "p",
    21: "p",
    22: "p",
    23: "p",
    24: "p",
    25: "p",
    26: "p",
    54: "P",
    55: "P",
    56: "P",
    57: "P",
    58: "P",
    59: "P",
    60: "P",
    61: "P",
    62: "P",
    64: "B",
    70: "R",
    72: "L",
    73: "N",
    74: "S",
    75: "G",
    76: "K",
    77: "G",
    78: "S",
    79: "N",
    80: "L"
  }
);

// List of moves generated from PMN (https://developer.sashite.com/specs/portable-move-notation)
var moves = [
  [   56, 47, 'P'       ],  [ 3, 11, 'g' ],
  [   64, 24, '+B', 'P' ],  [ 5, 14, 'g' ],
  [   24, 14, '+B', 'G' ],  [ 4,  3, 'k' ],
  [ null, 13, 'G'       ]
];

var lastPosition = moves.reduce(function(position, move) {
  return position.play(move);
}, startingPosition);

lastPosition.inHand;
// => [ 'P' ]

lastPosition.square;
// =>  {
//       '0': 'l',
//       '1': 'n',
//       '2': 's',
//       '3': 'k',
//       '6': 's',
//       '7': 'n',
//       '8': 'l',
//       '10': 'r',
//       '11': 'g',
//       '13': 'G',
//       '14': '+B',
//       '16': 'b',
//       '18': 'p',
//       '19': 'p',
//       '20': 'p',
//       '21': 'p',
//       '22': 'p',
//       '23': 'p',
//       '25': 'p',
//       '26': 'p',
//       '47': 'P',
//       '54': 'P',
//       '55': 'P',
//       '57': 'P',
//       '58': 'P',
//       '59': 'P',
//       '60': 'P',
//       '61': 'P',
//       '62': 'P',
//       '70': 'R',
//       '72': 'L',
//       '73': 'N',
//       '74': 'S',
//       '75': 'G',
//       '76': 'K',
//       '77': 'G',
//       '78': 'S',
//       '79': 'N',
//       '80': 'L'
//     }

License

The code is available as open source under the terms of the MIT License.

About Sashite

This package is maintained by Sashite.

With some lines of code, let's share the beauty of Chinese, Japanese and Western cultures through the game of chess!