// index corresponds to difference in player rank const KOMI_REC = { '9': [ 5.5, 2.5, -0.5, -3.5, -6.5, -9.5, 12.5, 15.5, 18.5, 21.5 ], '13': [ 5.5, 0.5, -5.5, 0.5, -5.5, 0.5, -5.5, 0.5, -5.5, 0.5 ], '19': [ 7.5, 0.5, 0.5, 0.5, 0.5, 0.5, 0.5, 0.5, 0.5, 0.5 ] } const HANDI_REC = { '9': [ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 ], '13': [ 0, 0, 0, 2, 2, 3, 3, 4, 4, 5 ], '19': [ 0, 0, 2, 3, 4, 5, 6, 7, 8, 9 ] } // index represents handicap placement for different board-sizes, eg handiPlace['9][1] = { (3, 3), (7, 7) } // last array in each property also used for hoshi rendering const HANDI_PLACE = { 9 : [ 0, 0, [ '7-3', '3-7' ], // 2 [ '7-7', '7-3', '3-7' ], [ '3-3', '7-7', '3-7', '7-3' ] ], 13 : [ 0, 0, [ '4-10', '10-4' ], // 2 [ '10-10', '4-10', '10-4' ], [ '4-4', '10-10', '4-10', '10-4' ], [ '7-7', '4-4', '10-10', '4-10', '10-4' ], [ '7-4', '4-7', '4-4', '10-10', '4-10', '10-4' ], [ '7-7', '7-4', '4-7', '4-4', '10-10', '4-10', '10-4' ], [ '10-7', '7-4', '7-10', '4-7', '4-4', '10-10', '4-10', '10-4' ], [ '7-7', '10-7', '7-4', '7-10', '4-7', '4-4', '10-10', '4-10', '10-4' ], ], 19 : [ 0, 0, [ '4-16', '16-4' ], // 2 [ '16-16', '4-16', '16-4' ], [ '4-4', '16-16', '4-16', '16-4' ], [ '10-10', '4-4', '16-16', '4-16', '16-4' ], [ '10-4', '4-10', '4-4', '16-16', '4-16', '16-4' ], [ '10-10', '10-4', '4-10', '4-4', '16-16', '4-16', '16-4' ], [ '16-10', '10-4', '10-16', '4-10', '4-4', '16-16', '4-16', '16-4' ], [ '10-10', '16-10', '10-4', '10-16', '4-10', '4-4', '16-16', '4-16', '16-4' ], ] }; const pipeMap = (...funcs) => obj => { const arr = Object.entries(obj).reduce((acc, [key, value], i, arr) => { funcs.forEach(func => value = func(value, i, arr)); return [...acc, [key, value]]; },[]); return arr.reduce((acc, [key, value]) => { return { ...acc, [key]: value } }, {}); } const checkLegal = ({ point, Game }) => { // if stone (includes ko) return false let legal = false; if (point.stone) { return { ...point, legal }; } // if liberties return true // if group has liberties return true // if move would capture opposing group // set capturing object and return true point.legal = !point.stone ? true : false; return point; } const getBoardState = (Game) => { const getLegal = point => checkLegal({ point, Game }).legal ? 'l' : point.stone; return pipeMap(getLegal)(Game.boardState); } const getNeighbors = boardSize => (point, i, boardState) => { const { top, btm, lft, rgt} = point.neighbors; // boardState[0] = [ '1-1', Point({x:1, y:1, boardSize}) ] point.neighbors.top = top ? boardState[i - boardSize][1] : top; point.neighbors.btm = btm ? boardState[i + boardSize][1] : btm; point.neighbors.lft = lft ? boardState[i - 1][1] : lft; point.neighbors.rgt = rgt ? boardState[i + 1][1] : rgt; return point; } const initBoard = (game) => { const boardState = {}; const { boardSize, handicap } = game; for (let i = 0; i < Math.pow(boardSize, 2); i++) { const point = Point({ x: Math.floor(i / boardSize) + 1, y: i % boardSize + 1, boardSize }); boardState[`${point.pos.x}-${point.pos.y}`] = point; } if (handicap) { HANDI_PLACE[boardSize][handicap].forEach(pt => { boardState[pt].makeMove(game); }); game.turn *= -1; } const boardStateWithNeighbors = pipeMap(getNeighbors(boardSize))(boardState) return boardStateWithNeighbors; } // returns Game object const Game = ({gameData = {}, gameRecord = []} = {}) => ({ winner: gameData.winner ||null, turn: gameData.turn || 0, // turn logic depends on handicap stones pass: gameData.pass || 0, // -1 represents state in which resignation has been submitted, not confirmed komi: gameData.komi || 6.5, // komi depends on handicap stones + player rank handicap: gameData.handicap || 0, boardSize: gameData.boardSize || 19, groups: {}, boardState: {}, gameRecord: gameRecord, playerState: gameData.playerState || { bCaptures: 0, wCaptures: 0, bScore: 0, wScore: 0 }, initGame: function() { this.winner = null; this.pass = 0; this.turn = 1; this.boardState = initBoard(this) return { ...this, legalMoves: getBoardState(this)}; }, getMeta: function() { return { winner: this.winner, turn: this.turn, pass: this.pass, playerState: this.playerState, gameRecord: this.gameRecord } }, makeMove: function({ player, pos: {x, y}}) { let success = false; const point = this.boardState[`${x}-${y}`]; const isTurn = ( this.turn === 1 && player === 'black' ) || ( this.turn === -1 && player === 'white' ); if (isTurn) { if (point.legal) { point.makeMove(this); this.turn *= -1; success = true; } } return {...this, legalMoves: getBoardState(this), success }; }, initGroup: function(point) { const newSymbol = Symbol(`${point.pos.x}-${point.pos.y}`); this.groups[newSymbol] = { stones: new Set(), liberties: new Set()}; return newSymbol; } }); const Point = ({x, y, boardSize = 19}) => ({ pos: {x, y}, stone: 0, // can be 1, -1, 0, or 'k' for ko legal: true, territory: 0, capturing: [], group: null, neighbors: { top: x > 1 ? `${ x - 1 }-${ y }` : null, btm: x < boardSize ? `${ x + 1 }-${ y }` : null, rgt: y < boardSize ? `${ x }-${ y + 1 }` : null, lft: y > 1 ? `${ x }-${ y - 1 }` : null }, makeMove: function(game) { this.stone = game.turn; this.legal = false; return this.joinGroup({ point: this, game }); }, joinGroup: function({ point, game }) { if (point.group !== this.group || !point.group) { // if point has no group set current group to new Symbol in game object if (!point.group) { point.group = game.initGroup(point); } // add current point to global group and override current group game.groups[point.group].stones.add(this); this.group = point.group; this.setLiberties(game); for (let neighbor of Object.values(this.neighbors)) { if ( neighbor.stone === this.stone // this check prevents infinite call chains && neighbor.group !== this.group ) { neighbor.joinGroup({ point: this, game }); } } } }, setLiberties: function(game) { const neighbors = Object.values(this.neighbors); const liberties = game.groups[this.group].liberties; // if point is occupied remove it from liberties set of point group, else add it neighbors.forEach( pt => pt ? liberties.delete(pt) : liberties.add(pt) ); } }); module.exports = { Game, Point }