import { render, screen } from '@testing-library/react';
import userEvent from '@testing-library/user-event';
import { vi, test, expect } from 'vitest';

vi.mock('../utils/icsFile.js', async (orig) => ({ ...(await orig()), downloadIcs: vi.fn() }));
import SessionSchedule, { sessionsOf } from './SessionSchedule.jsx';
import { downloadIcs } from '../utils/icsFile.js';

const chunk = (id, s, e, x = {}) => ({ id, startVerse: s, endVerse: e, ...x });
const project = {
  title: 'Romans 8', series: 'Romans', chapters: [{ book: 'Romans', bookAbbrev: 'ROM', chapter: '8', verses: [], chunks: [
    chunk('a', 1, 11, { episodeNumber: '4', episodeTitle: 'No condemnation' }), chunk('b', 12, 17),
  ] }],
};

test('each chunk is a session named for the series, its number and title (or passage)', () => {
  const s = sessionsOf(project);
  expect(s[0].title).toBe('Romans — Session 4: No condemnation');
  expect(s[1].title).toMatch(/^Romans — Session 2: Romans 8:12/);
});

test('the calendar file has one event per session, spaced as asked', async () => {
  const user = userEvent.setup();
  render(<SessionSchedule project={project} />);
  await user.clear(screen.getByLabelText('First session'));
  await user.type(screen.getByLabelText('First session'), '2026-10-11');
  await user.click(screen.getByRole('button', { name: /download calendar file/i }));
  const [text, name] = downloadIcs.mock.calls[0];
  expect(name).toBe('romans-8-schedule.ics');
  expect(text.match(/BEGIN:VEVENT/g)).toHaveLength(2);
  expect(text).toContain('DTSTART;VALUE=DATE:20261011');
  expect(text).toContain('DTSTART;VALUE=DATE:20261018'); // a week later
});

test('a study with no chunks shows nothing', () => {
  const { container } = render(<SessionSchedule project={{ title: 'x', chapters: [] }} />);
  expect(container).toBeEmptyDOMElement();
});