game-kit/template/deploy/replay-ledgers.ts

// Replays every ledger in a directory with THIS checkout's engine and, when
// a server address is given, compares the result with what that server is
// showing for the room: the round reached and the outcome. A ledger the
// engine cannot replay, or replays differently, is reported and fails the
// run. Used by deploy/verify-ledgers.sh.
//   tsx deploy/replay-ledgers.ts <ledger-dir> [https://host]

import { readdirSync, readFileSync } from 'node:fs';
import { join } from 'node:path';
import { game } from '../src/lib/game';
import type { SeatId } from '../src/lib/game/spec';

interface Seat {
	id: SeatId;
	name: string;
	token: string;
	bot: boolean;
}

const [dir, host] = process.argv.slice(2);
if (!dir) {
	console.error('usage: replay-ledgers.ts <ledger-dir> [https://host]');
	process.exit(2);
}

async function main(): Promise<void> {
	const files = readdirSync(dir).filter((f) => f.endsWith('.jsonl'));
	let failures = 0;
	for (const file of files) {
		const code = file.slice(0, -'.jsonl'.length);
		const lines = readFileSync(join(dir, file), 'utf8')
			.split('\n')
			.filter((l) => l.trim())
			.map((l) => JSON.parse(l));
		const seats: Seat[] = [];
		let state: ReturnType<typeof game.create> | null = null;
		let turns = 0;
		try {
			for (const line of lines) {
				if (line.t === 'seat') seats.push(line);
				else if (line.t === 'unseat') seats.splice(seats.findIndex((s) => s.id === line.id), 1);
				else if (line.t === 'start') state = game.create(Object.fromEntries(seats.map((s) => [s.id, s.name])), line.seed, line.rules ?? 1);
				else if (line.t === 'turn' && state) {
					state = game.resolve(state, line.inputs);
					turns += 1;
				}
			}
		} catch (e) {
			console.log(`${code}: REFUSED at turn ${turns + 1}: ${e instanceof Error ? e.message : String(e)}`);
			failures += 1;
			continue;
		}
		const outcome = state ? game.over(state) : null;
		let verdict = state ? `${turns} turns, ${outcome ? 'over' : 'in play'}` : 'not started';
		const human = seats.find((s) => !s.bot);
		if (host && state && human) {
			const res = await fetch(`${host}/api/rooms/${code}?token=${encodeURIComponent(human.token)}`);
			if (!res.ok) {
				verdict += `, server ${res.status}`;
			} else {
				const theirs = (await res.json()) as { turn: number | null; over: { winner: SeatId | null } | null };
				const same = theirs.turn === game.turn(state) && (theirs.over?.winner ?? null) === (outcome?.winner ?? null);
				if (!same) {
					failures += 1;
					verdict += `, DIFFERS from the server (server round ${theirs.turn}, local round ${game.turn(state)})`;
				} else verdict += ', matches the server';
			}
		}
		console.log(`${code}: ${verdict}`);
	}
	console.log(`${files.length} ledger${files.length === 1 ? '' : 's'}, ${failures} problem${failures === 1 ? '' : 's'}`);
	process.exit(failures ? 1 : 0);
}

void main();