polycode-sim/simulator.py

#!/usr/bin/env python3
"""PolyCode Simulator v0.1 — single-run demo."""
from __future__ import annotations

import json
import random
from dataclasses import asdict, dataclass
from datetime import UTC, datetime
from pathlib import Path

from strategies import (
    LenientVoter,
    Proposal,
    RandomInvestor,
    ThresholdInvestor,
    ValueVoter,
)


@dataclass
class RoundResult:
    round: int
    proposal_id: int
    funded: float
    approved: bool
    effort: float
    value: float


@dataclass
class RunSummary:
    accepted: int
    rejected: int
    total_funded: float
    acceptance_rate: float
    rounds: list[RoundResult]


def load_params(path: Path | None = None) -> dict:
    params_path = path or Path(__file__).with_name("params_default.json")
    return json.loads(params_path.read_text(encoding="utf-8"))


def make_proposal(round_idx: int, rng: random.Random) -> Proposal:
    effort = rng.uniform(30, 120)
    value = effort * rng.uniform(0.7, 1.4)
    return Proposal(id=round_idx, effort=round(effort, 2), value=round(value, 2))


def run_simulation(params: dict | None = None) -> RunSummary:
    params = params or load_params()
    rng = random.Random(params.get("random_seed", 42))
    investors = [ThresholdInvestor(), RandomInvestor(), RandomInvestor()]
    voters = [ValueVoter(), ValueVoter(), LenientVoter(), LenientVoter(), ValueVoter()]

    capital = float(params["initial_capital"])
    threshold = float(params["funding_threshold"])
    rounds: list[RoundResult] = []
    accepted = rejected = 0
    total_funded = 0.0

    for i in range(int(params["rounds"])):
        proposal = make_proposal(i + 1, rng)
        funded = 0.0
        for investor in investors:
            stake = min(capital, capital / len(investors))
            amount = investor.allocate(proposal, funded, stake, rng)
            amount = min(amount, capital)
            funded += amount
            capital -= amount
            if funded >= threshold:
                break

        votes = sum(1 for voter in voters if voter.approve(proposal, funded, rng))
        approved = votes > len(voters) / 2 and funded >= proposal.effort
        if approved:
            accepted += 1
        else:
            rejected += 1
            capital += funded * 0.5
        total_funded += funded
        rounds.append(
            RoundResult(
                round=i + 1,
                proposal_id=proposal.id,
                funded=round(funded, 2),
                approved=approved,
                effort=proposal.effort,
                value=proposal.value,
            )
        )

    total = accepted + rejected
    return RunSummary(
        accepted=accepted,
        rejected=rejected,
        total_funded=round(total_funded, 2),
        acceptance_rate=round(accepted / total, 3) if total else 0.0,
        rounds=rounds,
    )


def write_run(summary: RunSummary, params: dict, out_dir: Path | None = None) -> Path:
    out_dir = out_dir or Path("runs")
    out_dir.mkdir(exist_ok=True)
    stamp = datetime.now(UTC).strftime("%Y%m%dT%H%M%SZ")
    path = out_dir / f"run-{stamp}.json"
    payload = {
        "params": params,
        "summary": {
            "accepted": summary.accepted,
            "rejected": summary.rejected,
            "total_funded": summary.total_funded,
            "acceptance_rate": summary.acceptance_rate,
        },
        "rounds": [asdict(r) for r in summary.rounds],
    }
    path.write_text(json.dumps(payload, indent=2), encoding="utf-8")
    return path


def main() -> None:
    params = load_params()
    summary = run_simulation(params)
    out = write_run(summary, params)
    print(f"PolyCode demo run complete: {summary.accepted} accepted, {summary.rejected} rejected")
    print(f"acceptance_rate={summary.acceptance_rate} total_funded={summary.total_funded}")
    print(f"output: {out}")


if __name__ == "__main__":
    main()