import { useQuery } from '@tanstack/react-query';
import { Center, Icon, Spinner } from '@barev/ui';
import { I18nProvider, match, pickLocale, telegramLanguage, useI18n, useLocation, useTelegramBack, useTRPC } from '@barev/web';
import type { ReactNode } from 'react';
import { Consent } from './screens/Consent.tsx';
import { Docs } from './screens/Docs.tsx';
import { Move } from './screens/Move.tsx';
import { Segment } from './screens/Segment.tsx';
import { ServiceRequest } from './screens/ServiceRequest.tsx';
import { Home } from './screens/Home.tsx';
import { Membership } from './screens/Membership.tsx';
import { OrderDetail } from './screens/OrderDetail.tsx';
import { OrderForm } from './screens/OrderForm.tsx';
import { Orders } from './screens/Orders.tsx';
import { Perks } from './screens/Perks.tsx';
import { Profile } from './screens/Profile.tsx';
import { Services } from './screens/Services.tsx';
import { Chat } from './screens/Chat.tsx';

const ROOTS = ['/', '/services', '/perks', '/profile', '/docs'];

export function App({ hasInitData }: { hasInitData: boolean }) {
  const trpc = useTRPC();
  const me = useQuery({ ...trpc.client.me.queryOptions(), enabled: hasInitData });
  const locale = pickLocale(me.data?.locale, telegramLanguage(), navigator.language);

  return (
    <I18nProvider initial={locale}>
      {!hasInitData || me.error?.data?.httpStatus === 401 ? (
        <OpenInTelegram />
      ) : me.isPending ? (
        <Center>
          <Spinner />
        </Center>
      ) : me.error ? (
        <LoadError />
      ) : !me.data.consented ? (
        <Consent />
      ) : !me.data.segment ? (
        <Segment />
      ) : (
        <Routes segment={me.data.segment} />
      )}
    </I18nProvider>
  );
}

/**
 * Два сценария: MOVING — план переезда, документы, консьерж; LIVING — услуги со скидками, партнёры, заказы.
 * Остальные экраны (услуги, подписка, заказы) доступны из обоих.
 */
function Routes({ segment }: { segment: 'MOVING' | 'LIVING' }) {
  const { path } = useLocation();
  useTelegramBack(path, ROOTS);
  let screen: ReactNode;
  let m: Record<string, string> | null;
  if (path === '/') screen = segment === 'MOVING' ? <Move /> : <Home />;
  else if (path === '/docs') screen = <Docs />;
  else if ((m = match('/request/:code', path))) screen = <ServiceRequest code={m.code!} />;
  else if (path === '/services') screen = <Services />;
  else if ((m = match('/order/:code', path))) screen = <OrderForm code={m.code!} />;
  else if (path === '/orders') screen = <Orders />;
  else if ((m = match('/orders/:id', path))) screen = <OrderDetail id={m.id!} />;
  else if (path === '/perks') screen = <Perks />;
  else if (path === '/profile') screen = <Profile />;
  else if (path === '/membership') screen = <Membership />;
  else if (path === '/chat') screen = <Chat />;
  else screen = segment === 'MOVING' ? <Move /> : <Home />;
  const withNav = ROOTS.includes(path) || path === '/orders';
  return (
    <>
      {screen}
      {withNav && (segment === 'MOVING' ? <MoveNav path={path} /> : <BottomNav path={path} />)}
    </>
  );
}

/** Меню переезда: План / Документы / Консьерж (чат с ботом) / Услуги / Профиль */
function MoveNav({ path }: { path: string }) {
  const { t } = useI18n();
  const item = (href: string, icon: Parameters<typeof Icon>[0]['name'], label: string) => (
    <a href={`#${href}`} aria-current={path === href ? 'page' : undefined}>
      <Icon name={icon} size={22} />
      {label}
    </a>
  );
  return (
    <nav className="bc-bottomnav" aria-label={t('client.nav.label')}>
      {item('/', 'globe', t('client.nav.plan'))}
      {item('/docs', 'docs', t('client.nav.docs'))}
      <a href="#/chat" className="bc-bottomnav__plus" aria-label={t('client.concierge.title')}>
        <Icon name="chat" size={24} strokeWidth={2.4} />
      </a>
      {item('/services', 'grid', t('client.nav.services'))}
      {item('/profile', 'user', t('client.nav.profile'))}
    </nav>
  );
}

/** ORD-1: Главная / Услуги / + / Скидки / Профиль */
function BottomNav({ path }: { path: string }) {
  const { t } = useI18n();
  const item = (href: string, icon: Parameters<typeof Icon>[0]['name'], label: string) => (
    <a href={`#${href}`} aria-current={path === href ? 'page' : undefined}>
      <Icon name={icon} size={22} />
      {label}
    </a>
  );
  return (
    <nav className="bc-bottomnav" aria-label={t('client.nav.label')}>
      {item('/', 'home', t('client.nav.home'))}
      {item('/services', 'grid', t('client.nav.services'))}
      <a href="#/order/cleaning" className="bc-bottomnav__plus" aria-label={t('client.nav.newOrder')}>
        <Icon name="plus" size={26} strokeWidth={2.6} />
      </a>
      {item('/perks', 'gift', t('client.nav.perks'))}
      {item('/profile', 'user', t('client.nav.profile'))}
    </nav>
  );
}

function OpenInTelegram() {
  const { t } = useI18n();
  return (
    <div className="app app--plain">
      <Center>
        <div className="bc-stack" style={{ textAlign: 'center', alignItems: 'center' }}>
          <Icon name="logo" size={48} style={{ color: 'var(--bc-plum)' }} />
          <h1 className="bc-h2">{t('client.openInTelegram.title')}</h1>
          <p className="bc-muted">{t('client.openInTelegram.text')}</p>
        </div>
      </Center>
    </div>
  );
}

function LoadError() {
  const { t } = useI18n();
  return (
    <div className="app app--plain">
      <Center>
        <div className="bc-stack" style={{ textAlign: 'center', alignItems: 'center' }}>
          <p>{t('errors.generic')}</p>
          <button className="bc-btn bc-btn--dark" onClick={() => window.location.reload()}>
            {t('common.retry')}
          </button>
        </div>
      </Center>
    </div>
  );
}