Shogi MCP Server

// engine.js const { spawn } = require("node:child_process"); const DEBUG = process.env.DEBUG === "1"; class LineReader { constructor(onLine) { this.buf = ""; this.onLine = onLine; } push(chunk) { this.buf += chunk.toString(); let idx; while ((idx = this.buf.indexOf("\n")) >= 0) { const line = this.buf.slice(0, idx).trim(); this.buf = this.buf.slice(idx + 1); if (line) this.onLine(line); } } } class Mutex { constructor() { this.p = Promise.resolve(); } async run(fn) { let release; const wait = new Promise((r) => (release = r)); const prev = this.p; this.p = this.p.then(() => wait); await prev; try { return await fn(); } finally { release(); } } } function parseInfo(line) { const g = {}; const mDepth = /(?:^| )depth (\d+)/.exec(line); const mMPV = /(?:^| )multipv (\d+)/.exec(line); const mCp = / score cp (-?\d+)/.exec(line); const mMate = / score mate (-?\d+)/.exec(line); const mNodes= / nodes (\d+)/.exec(line); const mNps = / nps (\d+)/.exec(line); const mPv = / pv (.+)$/.exec(line); if (mDepth) g.depth = Number(mDepth[1]); if (mMPV) g.multipv = Number(mMPV[1]); if (mCp) g.scoreCp = Number(mCp[1]); if (mMate) g.mate = Number(mate = mMate[1]); if (mNodes) g.nodes = Number(mNodes[1]); if (mNps) g.nps = Number(mNps[1]); if (mPv) g.pv = mPv[1].trim().split(/\s+/); return g; } class AIEngine { constructor(enginePath, opts = {}) { this.enginePath = enginePath; this.defaultThreads = opts.defaultThreads ?? 1; this.defaultHashMB = opts.defaultHashMB ?? 256; this.proc = null; this.ready = false; this.mutex = new Mutex(); this.pending = null; this._start(); } _log(...a){ if (DEBUG) console.log("[engine]", ...a); } _start() { this.proc = spawn(this.enginePath, [], { cwd: process.cwd() }); this.proc.on("exit", (c, s) => console.error(`[engine] exited code=${c} sig=${s}`)); this.proc.on("error", (e) => console.error(`[engine] failed to start: ${e.message}`)); const out = new LineReader((line) => this._onLine(line)); this.proc.stdout.on("data", (d) => out.push(d)); this.proc.stderr.on("data", (d) => process.stderr.write(d.toString())); this.ready = false; this._write("usi"); } _write(s) { this._log(">>", s); this.proc.stdin.write(s + "\n"); } _onLine(line) { this._log("<<", line); if (line === "usiok") { this._write("isready"); return; } if (line === "readyok") { this.ready = true; this._write(`setoption name Threads value ${this.defaultThreads}`); this._write(`setoption name Hash value ${this.defaultHashMB}`); if (process.env.EVAL_FILE) this._write(`setoption name EvalFile value ${process.env.EVAL_FILE}`); if (process.env.EVAL_DIR) this._write(`setoption name EvalDir value ${process.env.EVAL_DIR}`); return; } if (this.pending && line.startsWith("info ")) { const parsed = parseInfo(line); if (parsed.multipv) { const idx = parsed.multipv; this.pending.results[idx] = { ...(this.pending.results[idx] || {}), ...parsed }; } return; } if (this.pending && line.startsWith("bestmove ")) { const bestmove = line.split(" ")[1]; const infos = Object.values(this.pending.results) .sort((a, b) => (a.multipv || 999) - (b.multipv || 999)); const resolve = this.pending.resolve; this.pending = null; resolve({ bestmove, infos }); } } async _waitReady(timeoutMs = 4000) { const start = Date.now(); while (!this.ready) { await new Promise((r) => setTimeout(r, 50)); if (Date.now() - start > timeoutMs) throw new Error("engine not ready (usi/readyok not received)"); } } // sfen: "startpos" も OK / "startpos moves ..." もそのまま渡せる _writePosition(sfen, forceMove) { const isStartpos = /^startpos(\s|$)/.test(sfen); if (isStartpos) { // すでに moves を含むならそのまま、無ければ forceMove を付加 if (forceMove) { if (/(\s|^)moves(\s|$)/.test(sfen)) this._write(`position ${sfen}`); else this._write(`position ${sfen} moves ${forceMove}`); } else { this._write(`position ${sfen}`); } } else { // こちらは SFEN 形式 if (forceMove) this._write(`position sfen ${sfen} moves ${forceMove}`); else this._write(`position sfen ${sfen}`); } } /** * @param {{sfen:string, depth:number, multipv:number, threads?:number, forceMove?:string}} params */ async analyze({ sfen, depth, multipv, threads = this.defaultThreads, forceMove }) { return this.mutex.run(async () => { await this._waitReady(); this._write(`setoption name MultiPV value ${multipv}`); if (threads && threads !== this.defaultThreads) this._write(`setoption name Threads value ${threads}`); this._writePosition(sfen, forceMove); const timeoutMs = Math.max(8000, 400 * depth); const results = {}; const prom = new Promise((resolve, reject) => { const timer = setTimeout(() => { if (this.pending) { this.pending = null; reject(new Error("engine timeout (no bestmove)")); } }, timeoutMs); this.pending = { results, resolve: (v) => { clearTimeout(timer); resolve(v); } }; }); this._write(`go depth ${depth}`); return prom; }); } } module.exports = { AIEngine };