import { render } from 'preact';
import { readBootstrap } from './bootstrap';
import { App } from './App';
import { createT } from './i18n';
import { WidgetApi, buildCapabilities } from './widget-api';
import './styles.css';

// Input-mode detector for hover styling. CSS gates `:hover` and
// `:focus-visible` rules on `:root[data-input="mouse"]` because Capacitor's
// Android Chromium WebView synthesises `:hover` on the focused element
// after a tap and never clears it until the next interaction elsewhere —
// without the gate, every tap leaves a sticky hover state on the tapped
// card («card greys out after tap and only un-greys when you tap a
// different button»).
//
// Truth comes from `pointerdown.pointerType`. The capture-phase listener
// runs in the same task as any post-tap `:hover` synthesis, so a touch
// tap on Android lands in 'touch' mode in the same render frame as the
// synthesised hover would paint.
//
// Initial mode is plain 'mouse'. matchMedia-based guessing was tried
// here and dropped — every interaction-media query is mis-reported on at
// least one shipping device: Capacitor Android WebView falsely matches
// `hover: hover` and `any-pointer: fine` on pure-touch phones;
// Samsung / OnePlus / Moto Androids expose a virtual-mouse HID and
// falsely match `pointer: fine`; older Firefox-on-Windows desktops
// reported `pointer: coarse` despite a real mouse. Defaulting to 'mouse'
// is strictly no worse than any of those queries on any device: a
// desktop / hybrid user gets hover affordances from frame zero, and a
// touch user cannot trigger `:hover` before tapping because there is no
// pointer hovering anything — by the time the first tap fires
// `:hover` (synthesised), our listener has already moved the attribute
// to 'touch'. Pen / stylus also lands in 'touch' (pointerType is `pen`,
// matched by the `!== 'mouse'` branch).
const setInputMode = (mode: 'touch' | 'mouse'): void => {
  document.documentElement.dataset.input = mode;
};
setInputMode('mouse');
window.addEventListener(
  'pointerdown',
  (event) => {
    setInputMode(event.pointerType === 'mouse' ? 'mouse' : 'touch');
  },
  { passive: true, capture: true }
);

const root = document.getElementById('app');
if (!root) {
  throw new Error('#app root element missing — index.html out of sync');
}

const result = readBootstrap(window.location.search);

if (!result.ok) {
  // Either someone opened the widget URL directly (no host params), or a
  // host bug failed to provide them. Either way render a self-contained
  // diagnostic instead of going silent. Bootstrap failed before we could
  // read clientLanguage from the URL, so let createT fall back to
  // navigator.language.
  const t = createT();
  render(
    <div class="app">
      <div class="error-banner">
        <strong>{t('bootstrap.failed')}</strong>
        {t('bootstrap.missing-params', { names: result.missing.join(', ') })}{' '}
        {t('bootstrap.embedded-only', { route: '/bots/telegram' })}
      </div>
    </div>,
    root
  );
} else {
  // Apply initial theme synchronously so the first paint isn't flashed
  // through the wrong palette.
  document.documentElement.dataset.theme = result.bootstrap.theme;

  // Instantiate the WidgetApi BEFORE React render. The constructor attaches
  // the `window.addEventListener('message', ...)` listener synchronously,
  // so by the time the host's ClientWidgetApi fires its capabilities
  // request on iframe `load` we're already listening.
  //
  // The pre-fix flow built the WidgetApi inside App.tsx's useEffect, which
  // runs AFTER React's first commit. On a fresh mount the bundle parse +
  // initial render took long enough for the host's request to arrive
  // after the listener was attached, so it worked by accident. On the
  // *second* mount (after «Show chat» → «Show widget») the bundle is
  // browser-cached and parses near-instantly; the host's request raced
  // ahead of useEffect, the listener missed it, and capability handshake
  // hung forever — only the «Соединение с Vojo…» diag line ever showed.
  const api = new WidgetApi(result.bootstrap, buildCapabilities(result.bootstrap.roomId));
  render(<App bootstrap={result.bootstrap} api={api} />, root);
}