import { describe, it, expect, vi } from 'vitest';
import { readFileSync } from 'node:fs';

/**
 * AC-3 itself — *"the suite fails loudly rather than skipping green"* — which nothing asserted.
 *
 * ⛔ Story 4.4 review, HIGH-3. The behaviour was correct and verified only by a reviewer running it by hand. Its corpus
 * twin has exactly this spec, and for a stated reason: without mocking `node:fs`, *"the only branch reachable from here
 * is the one that was never broken"*. The throw branch is the whole point of the guard, and it was untested.
 *
 * This spec lives in `unit`, not `corpus`: it mocks the filesystem, so it needs no checkout — which is also the only
 * way the ABSENT case can be exercised on a machine that has one.
 */
const GUARD = 'apps/cli/src/__tests__/goldenCheckout.ts';

describe('an absent golden checkout is a failure, not a skip (AC-3)', () => {
  const loadWithoutFixtures = async (): Promise<unknown> => {
    vi.resetModules();
    vi.doMock('node:fs', () => ({ existsSync: () => false }));
    try {
      const module = (await import('./goldenCheckout.js')) as {
        goldenSuite: (a: string, b: string, c: string) => unknown;
      };
      return module.goldenSuite(
        'golden-flows',
        'Cannot run.',
        'Because nothing is there.',
      );
    } finally {
      vi.doUnmock('node:fs');
      vi.resetModules();
    }
  };

  it('throws rather than returning a skippable suite', async () => {
    await expect(loadWithoutFixtures()).rejects.toThrow(/No golden fixtures/);
  });

  it("says what was lost, in the caller's own words", async () => {
    // The three arguments exist so the message names what THIS suite cannot check, not a generic absence.
    await expect(loadWithoutFixtures()).rejects.toThrow(
      /Cannot run\. Because nothing is there\./,
    );
  });

  it('says how to fix it BOTH ways — clone it, or stop selecting these', async () => {
    const error = (await loadWithoutFixtures().catch(
      (e: unknown) => e,
    )) as Error;
    expect(error.message, 'names the repository to clone').toContain(
      'hexasync-ideation-hub',
    );
    expect(error.message, 'names the override').toContain(
      'HEXASYNC_CONNECTIONS_FEATURE',
    );
    expect(error.message, 'names the CI escape').toContain('yarn test:ci');
    // And the resolved path, so a wrong override is visible rather than mysterious.
    expect(error.message).toContain('golden-flows/fixtures');
  });

  it('never consults process.env.CI', () => {
    // A guard keyed on CI decides for the runner instead of stating a fact about the machine it is on.
    expect(readFileSync(GUARD, 'utf8')).not.toContain('process.env.CI');
  });

  it('returns a suite with NO `.skip`, so AC-3 cannot be opted out of', () => {
    /**
     * `corpusCheckout.ts` narrows its return type for exactly this reason — *"Narrower than `typeof describe` on
     * purpose"*. This file used `typeof describe`, which carries `.skip`, so `goldenSuite(...).skip(...)` compiled
     * cleanly — re-opening the escape hatch the module exists to close.
     */
    // The DECLARATION, not the prose: the docblock explaining the fix names the old type, and matching the whole file
    // failed on the very comment that records why it changed.
    expect(
      readFileSync(GUARD, 'utf8'),
      'the return type re-opens `.skip`',
    ).not.toMatch(/type Suite\s*=\s*typeof describe/);
  });
});