import assert from 'node:assert/strict';
import {readFile} from 'node:fs/promises';
import test from 'node:test';
import vm from 'node:vm';

const source = await readFile(new URL('./hop-native.js', import.meta.url), 'utf8');

function page({search = '', signedIn = false, fetchResult} = {}) {
  const dataset = {};
  const publicHomeLink = {
    classList: {toggle() {}},
    href: 'https://hop.test/',
  };
  let currentMainReplaced = false;
  const currentMain = {
    replaceWith() {
      currentMainReplaced = true;
    },
  };
  const publicMain = {
    parentElement: {querySelectorAll: () => []},
  };
  const document = {
    documentElement: {dataset},
    title: 'Dashboard',
    addEventListener() {},
    querySelector(selector) {
      if (selector === 'meta[name="hop-signed-user-id"]') return signedIn ? {} : null;
      if (selector === '[data-hop-public-home-link]') return signedIn ? publicHomeLink : null;
      if (selector === '[role="main"]') return currentMain;
      return null;
    },
    querySelectorAll() {
      return [];
    },
  };
  const context = {
    console: {error() {}},
    document,
    DOMParser: class {
      parseFromString() {
        return {
          title: 'Hop',
          querySelector: (selector) => selector === '#hop-main' ? publicMain : null,
        };
      }
    },
    fetch: fetchResult || (() => Promise.resolve({ok: true, text: () => Promise.resolve('<main id="hop-main"></main>')})),
    MutationObserver: class { observe() {} },
    URL,
    URLSearchParams,
    window: {
      location: {href: `https://hop.test/${search}`, origin: 'https://hop.test', pathname: '/', search},
      requestAnimationFrame() {},
    },
  };
  vm.runInNewContext(source, context);
  return {dataset, get currentMainReplaced() { return currentMainReplaced; }};
}

async function settle() {
  await new Promise((resolve) => setImmediate(resolve));
}

test('keeps the authenticated dashboard hidden until the public homepage is ready', async () => {
  let finishFetch;
  const fetchResult = () => new Promise((resolve) => { finishFetch = resolve; });
  const result = page({search: '?hop=home', signedIn: true, fetchResult});

  assert.equal(result.dataset.hopPublicHome, 'loading');
  assert.equal(result.dataset.hopNative, undefined);
  assert.equal(result.currentMainReplaced, false);

  finishFetch({ok: true, text: () => Promise.resolve('<main id="hop-main"></main>')});
  await settle();

  assert.equal(result.dataset.hopPublicHome, 'rendered');
  assert.equal(result.dataset.hopNative, 'true');
  assert.equal(result.currentMainReplaced, true);
});

test('reveals the existing page when the public homepage request fails', async () => {
  const result = page({
    search: '?hop=home',
    signedIn: true,
    fetchResult: () => Promise.reject(new Error('offline')),
  });

  assert.equal(result.dataset.hopNative, undefined);
  await settle();

  assert.equal(result.dataset.hopPublicHome, 'failed');
  assert.equal(result.dataset.hopNative, 'true');
  assert.equal(result.currentMainReplaced, false);
});

test('reveals ordinary pages immediately', () => {
  const result = page({signedIn: true});
  assert.equal(result.dataset.hopNative, 'true');
});