import * as fs from 'fs';
import * as os from 'os';
import * as path from 'path';
import { isBackportMissing } from './wwebjs-backport-check';

/**
 * Guards the startup diagnostic for an unpatched whatsapp-web.js (#889). The cost of getting this
 * wrong runs both ways: a missed detection restores the silence the check exists to break, and a
 * false alarm sends operators after a patch they do not need.
 */
describe('isBackportMissing', () => {
  const tmpDirs: string[] = [];

  /** A whatsapp-web.js install stubbed down to the one file the check reads. */
  function install(messageJs: string): string {
    const dir = fs.mkdtempSync(path.join(os.tmpdir(), 'wwjs-check-'));
    tmpDirs.push(dir);
    fs.mkdirSync(path.join(dir, 'src', 'structures'), { recursive: true });
    fs.writeFileSync(path.join(dir, 'src', 'structures', 'Message.js'), messageJs);
    return dir;
  }

  afterAll(() => {
    for (const dir of tmpDirs) fs.rmSync(dir, { recursive: true, force: true });
  });

  it('flags a tree that still reads the pre-rename id', () => {
    expect(isBackportMissing(install('this.id = data.id;'))).toBe(true);
  });

  it('accepts the shape our patcher lands', () => {
    expect(isBackportMissing(install('this.id = Base._normalizeId(data.id);'))).toBe(false);
  });

  it('accepts an upstream fix that inlines the $1 fallback instead', () => {
    // The check must stand down for any fix, not just ours — otherwise the first upstream release
    // that lands this differently makes every healthy install log a phantom error.
    expect(isBackportMissing(install('this.id = data.id._serialized || data.id.$1;'))).toBe(false);
  });

  it('stays quiet about an install it cannot inspect', () => {
    expect(isBackportMissing(path.join(os.tmpdir(), 'wwjs-not-installed-here'))).toBe(false);
  });

  it('can reach the file it reads in a real install', () => {
    // The no-argument path fails open, so a resolution that silently stopped working — an `exports`
    // map on a future whatsapp-web.js would do it — would retire the check without failing anything.
    const installed = path.dirname(require.resolve('whatsapp-web.js/package.json'));
    expect(fs.existsSync(path.join(installed, 'src', 'structures', 'Message.js'))).toBe(true);
  });
});