cutechess.py

from dataclasses import dataclass
from subprocess import PIPE, Popen
from pathlib import Path


@dataclass
class MatchResult:
    w: int
    l: int
    d: int
    elo_diff: float


class CutechessMan:

    def __init__(
        self,
        engine: str,
        book: str,
        games: int = 120,
        tc: float = 5.0,
        hash: int = 8,
        threads: int = 1,
        save_rate: int = 10,
        pgnout: str = "tuner/games.pgn",
        use_fastchess: bool = True
    ):
        self.engine = engine
        self.book = book
        self.games = games
        self.tc = tc
        self.inc = tc / 100
        self.hash_size = hash
        self.threads = threads
        self.save_rate = save_rate
        self.pgnout = pgnout
        self.use_fastchess = use_fastchess

    def get_cutechess_cmd(
        self,
        params_a: list[str],
        params_b: list[str]
    ) -> str:
        command = "fastchess -config discard=true outname=tuner/fastchess_config.json -output format=cutechess" if self.use_fastchess else "cutechess-cli"

        if Path("./tuner/" + command.split()[0]).exists():
            command = "./tuner/" + command

        return (
            f"{command} "
            f"-engine cmd=./tuner/{self.engine} name={self.engine}-1 proto=uci "
            f"option.Hash={self.hash_size} {' '.join(params_a)} "
            f"-engine cmd=./tuner/{self.engine} name={self.engine}-2 proto=uci "
            f"option.Hash={self.hash_size} {' '.join(params_b)} "
            "-resign movecount=3 score=400 "
            "-draw movenumber=40 movecount=8 score=10 "
            "-recover "
            f"-concurrency {self.threads} "
            f"-each tc={self.tc}+{self.inc} "
            f"-openings file=tuner/{self.book} "
            f"format={self.book.split('.')[-1]} order=random plies=16 "
            "-repeat 2 "
            "-games 2 "
            f"-rounds {self.games // 2} "
            f"-pgnout {self.pgnout}"
        )

    def run(self, params_a: list[str], params_b: list[str]) -> MatchResult:
        cmd = self.get_cutechess_cmd(params_a, params_b)
        print(cmd)
        cutechess = Popen(cmd.split(), stdout=PIPE)

        score = [0, 0, 0]
        elo_diff = 0.0

        while True:

            # Read each line of output until the pipe closes
            line = cutechess.stdout.readline().strip().decode('ascii')
            print(line)
            if not line:
                cutechess.wait()
                return MatchResult(*score, elo_diff)
            # Parse WLD score
            if line.startswith("Score of"):
                start_index = line.find(":") + 1
                end_index = line.find("[")
                split = line[start_index:end_index].split(" - ")

                score = [int(i) for i in split]

            # Parse Elo Difference
            if line.startswith("Elo difference"):
                start_index = line.find(":") + 1
                end_index = line.find("+")
                elo_diff = float(line[start_index:end_index])