import '@testing-library/jest-dom/vitest';
import userEvent from '@testing-library/user-event';
import { cleanup, findByText, render, screen } from '@testing-library/vue';
import {
  mockFetchDataStream,
  mockFetchDataStreamWithGenerator,
  mockFetchError,
} from '../tests/utils/mock-fetch';
import TestCompletionComponent from './TestCompletionComponent.vue';

beforeEach(() => {
  render(TestCompletionComponent);
});

afterEach(() => {
  vi.restoreAllMocks();
  cleanup();
});

it('should render complex text stream', async () => {
  mockFetchDataStream({
    url: 'https://example.com/api/completion',
    chunks: ['0:"Hello"\n', '0:","\n', '0:" world"\n', '0:"."\n'],
  });

  await userEvent.type(screen.getByTestId('input'), 'hi{enter}');

  await screen.findByTestId('completion');
  expect(screen.getByTestId('completion')).toHaveTextContent('Hello, world.');
});

describe('loading state', () => {
  it('should show loading state', async () => {
    let finishGeneration: ((value?: unknown) => void) | undefined;
    const finishGenerationPromise = new Promise(resolve => {
      finishGeneration = resolve;
    });

    mockFetchDataStreamWithGenerator({
      url: 'https://example.com/api/chat',
      chunkGenerator: (async function* generate() {
        const encoder = new TextEncoder();
        yield encoder.encode('0:"Hello"\n');
        await finishGenerationPromise;
      })(),
    });

    await userEvent.type(screen.getByTestId('input'), 'hi{enter}');

    await screen.findByTestId('loading');
    expect(screen.getByTestId('loading')).toHaveTextContent('true');

    finishGeneration?.();

    await findByText(await screen.findByTestId('loading'), 'false');
    expect(screen.getByTestId('loading')).toHaveTextContent('false');
  });

  it('should reset loading state on error', async () => {
    mockFetchError({ statusCode: 404, errorMessage: 'Not found' });

    await userEvent.type(screen.getByTestId('input'), 'hi{enter}');

    await screen.findByTestId('loading');
    expect(screen.getByTestId('loading')).toHaveTextContent('false');
  });
});