import { ServiceUnavailableException } from '@nestjs/common';

import { NcrRatingsClient } from './ncr-ratings.client';
const isin = 'RU000A10EW44';
const row = (value = 'AAA.ru', code = isin, href = '/ratings/issues/123/') =>
  `<tr><td>Эмитент</td><td>Облигация</td><td>${value}</td><td><a href="${href}">${code}</a></td><td>REG</td><td>17.04.2026</td></tr>`;
const table = (rows: string) =>
  `<table id="issues-table"><thead><tr><th>Лицо</th><th>Выпуск</th><th>Рейтинг</th><th>ISIN</th><th>Регномер</th><th>Дата</th></tr></thead><tbody>${rows}</tbody></table>`;
const response = (html: string) =>
  ({ ok: true, text: () => Promise.resolve(html) }) as Response;
const cacheClock = performance;
describe('public NCR issue ratings', () => {
  beforeEach(() => {
    jest.useFakeTimers().setSystemTime(new Date('2026-09-10T10:00:00Z'));
    jest.spyOn(cacheClock, 'now').mockImplementation(() => Date.now());
  });
  afterEach(() => {
    jest.restoreAllMocks();
    jest.useRealTimers();
  });
  it('matches only exact ISIN and shares one public registry download', async () => {
    const fetchMock = jest
      .spyOn(global, 'fetch')
      .mockResolvedValue(response(table(row())));
    const client = new NcrRatingsClient();
    const [rating, missing] = await Promise.all([
      client.rating(isin),
      client.rating('RU000A1065B1'),
    ]);
    expect(rating).toEqual({
      agency: 'NCR',
      value: 'AAA.ru',
      status: 'active',
      date: '2026-04-17',
      sourceUrl: 'https://ratings.ru/ratings/issues/123/',
      observedAt: '2026-09-10T10:00:00.000Z',
    });
    expect(missing).toBeNull();
    expect(await client.rating('issuer-name')).toBeNull();
    expect(fetchMock).toHaveBeenCalledTimes(1);
    await jest.advanceTimersByTimeAsync(6 * 60 * 60_000 + 1);
    await client.rating(isin);
    expect(fetchMock).toHaveBeenCalledTimes(2);
  });
  it('preserves withdrawal and never displays an issuer rating as an issue rating', async () => {
    jest
      .spyOn(global, 'fetch')
      .mockResolvedValue(response(table(row('рейтинг  отозван'))));
    expect(await new NcrRatingsClient().rating(isin)).toMatchObject({
      status: 'withdrawn',
      value: null,
    });
  });
  it.each([
    '<html>Service unavailable</html>',
    table(row('AAA.ru', isin, 'https://untrusted.test/')),
    table(row('unrecognized')),
    table(row() + row('AA.ru')),
    table(''),
  ])(
    'reports changed or ambiguous registry as unavailable, not unrated',
    async (html) => {
      jest.spyOn(global, 'fetch').mockResolvedValue(response(html));
      await expect(new NcrRatingsClient().rating(isin)).rejects.toBeInstanceOf(
        ServiceUnavailableException,
      );
    },
  );
  it.each(['AA+.ru', 'B-.ru', 'BBB+.ru', 'CCC-.ru', 'CC.ru', 'D.ru'])(
    'accepts the public rating grammar: %s', async (value) => {
      jest.spyOn(global, 'fetch').mockResolvedValue(response(table(row(value))));
      expect(await new NcrRatingsClient().rating(isin)).toMatchObject({ value });
    },
  );
  it.each(['AAA+.ru', 'CC-.ru', 'BBBB.ru', 'BBB++.ru'])(
    'rejects invalid rating grades: %s', async (value) => {
      jest.spyOn(global, 'fetch').mockResolvedValue(response(table(row(value))));
      await expect(new NcrRatingsClient().rating(isin)).rejects.toBeInstanceOf(ServiceUnavailableException);
    },
  );
  it('bounds outage retries then recovers without retaining a false missing rating', async () => {
    const fetchMock = jest
      .spyOn(global, 'fetch')
      .mockRejectedValueOnce(new Error('offline'))
      .mockResolvedValue(response(table(row())));
    const client = new NcrRatingsClient();
    await expect(client.rating(isin)).rejects.toBeInstanceOf(
      ServiceUnavailableException,
    );
    await expect(client.rating(isin)).rejects.toBeInstanceOf(
      ServiceUnavailableException,
    );
    expect(fetchMock).toHaveBeenCalledTimes(1);
    await jest.advanceTimersByTimeAsync(60_001);
    expect(await client.rating(isin)).toMatchObject({ value: 'AAA.ru' });
    expect(fetchMock).toHaveBeenCalledTimes(2);
  });
});