import './styles/tokens.css';
import './styles/layout.css';

import { registerSW } from 'virtual:pwa-register';
import { el } from './lib/dom.js';
import { initRouter, rerender } from './router.js';
import { Nav } from './components/Nav.js';
import { settings, applyTheme } from './store/settings.js';
import { ui } from './store/ui.js';

applyTheme();

// Own the scroll position ourselves (views restore it deliberately).
if ('scrollRestoration' in history) history.scrollRestoration = 'manual';
// Navigation scroll memory is per-session — start a cold launch at the top.
ui.set({ feedScroll: 0, searchScroll: 0 });

// Land on the configured default screen for a fresh launch (no hash yet at
// all — a bookmark, the home-screen icon, or typing the bare URL). Explicit
// navigation, like tapping "Dex" in the nav, is never redirected — that
// only ever touches location.hash after this point.
if (!location.hash) {
  const DEFAULT_ROUTES = { dex: '#/', team: '#/team', search: '#/search' };
  location.hash = DEFAULT_ROUTES[settings.get().defaultRoute] || '#/';
}

// React to preference changes. The dex feed updates itself in place, but the
// Pokémon detail page is built once per visit — rebuild it when the selected
// game changes so its data (flavour text, learnset, matchups, evolution,
// abilities, locations, era sprites) matches the new game.
let lastVersionGroup = settings.get().versionGroup;
settings.subscribe((s) => {
  applyTheme();
  if (s.versionGroup !== lastVersionGroup) {
    lastVersionGroup = s.versionGroup;
    if ((location.hash || '').startsWith('#/pokemon/')) rerender();
  }
});
window
  .matchMedia('(prefers-color-scheme: dark)')
  .addEventListener('change', () => applyTheme());

const app = document.getElementById('app');
app.replaceChildren();

const viewHost = el('main', { id: 'view', class: 'view-host' });
app.append(Nav(), viewHost);

initRouter(viewHost);

// --- Service worker: prompt to refresh rather than silently swapping ------
const updateSW = registerSW({
  onNeedRefresh() {
    showToast('A new version is available.', 'Reload', () => updateSW(true));
  },
  onOfflineReady() {
    showToast('Ready to use offline.', 'Dismiss');
  },
});

// --- Offline indicator -------------------------------------------------
const netPill = el('div', { class: 'netpill', role: 'status' }, 'Offline');
function syncNet() {
  if (navigator.onLine) {
    netPill.remove();
  } else if (!netPill.isConnected) {
    document.body.append(netPill);
  }
}
window.addEventListener('offline', syncNet);
window.addEventListener('online', () => {
  syncNet();
  showToast('Back online.', 'Dismiss');
});
syncNet();

function showToast(message, actionLabel, onAction) {
  const toast = el(
    'div',
    { class: 'toast', role: 'status' },
    el('span', {}, message),
    el(
      'button',
      {
        class: 'toast__action',
        type: 'button',
        onclick: () => {
          toast.remove();
          onAction?.();
        },
      },
      actionLabel,
    ),
  );
  document.body.append(toast);
  if (!onAction) setTimeout(() => toast.remove(), 5000);
}