import { describe, it, expect } from 'vitest';
import { NewsLedger } from '../src/sim/news.js';
import { generateGalaxy } from '../src/sim/galaxy.js';
import { priceOf } from '../src/sim/economy.js';

describe('NewsLedger', () => {
  it('records snapshots and serves them with lane delay', () => {
    const galaxy = generateGalaxy('news-test', { systemCount: 8 });
    const news = new NewsLedger();
    news.record(galaxy, 0);
    news.record(galaxy, 1);
    news.record(galaxy, 2);

    const pid = galaxy.planets[0].id;
    // 0 hops away at t=2: freshest snapshot (t=2)
    expect(news.knownPrices(pid, 0, 2).time).toBe(2);
    // 2 hops away at t=2: only the t=0 snapshot has reached us
    expect(news.knownPrices(pid, 2, 2).time).toBe(0);
    // far away early on: clamps to the universally-known t=0 snapshot
    expect(news.knownPrices(pid, 5, 1).time).toBe(0);
  });

  it('snapshot prices match the live price curve at record time', () => {
    const galaxy = generateGalaxy('news-test', { systemCount: 8 });
    const news = new NewsLedger();
    news.record(galaxy, 0);
    const p = galaxy.planets[0];
    const snap = news.knownPrices(p.id, 0, 0);
    expect(snap.prices.ore).toBeCloseTo(priceOf('ore', p.stock.ore), 5);
  });

  it('trims history beyond SNAPSHOT_KEEP entries', () => {
    const galaxy = generateGalaxy('news-test', { systemCount: 8 });
    const news = new NewsLedger();
    for (let t = 0; t <= 50; t++) news.record(galaxy, t);
    // a 45-day-old snapshot is gone; we get the oldest retained one instead
    const snap = news.knownPrices(galaxy.planets[0].id, 45, 50);
    expect(snap.time).toBeGreaterThanOrEqual(50 - 30);
  });
});