import { queueIcon } from '../shared/ui/icons';
import { unwrap } from '@pipu/core';
import { useQuery } from '@tanstack/react-query';
import { Link, Outlet, useNavigate } from '@tanstack/react-router';
import { Suspense, useCallback, useState, type ReactNode } from 'react';
import { useTranslation } from 'react-i18next';

import { useAuthState, useSession, useUser } from '../app/session';
import { useDesktop } from '../desktop';
import { useCollectionCounts } from '../entities/collection';
import {
  moreIcon,
  auditFillIcon,
  auditIcon,
  groupFillIcon,
  groupIcon,
  homeFillIcon,
  homeIcon,
  libraryFillIcon,
  libraryIcon,
  logoutIcon,
  historyFillIcon,
  historyIcon,
  likeFillIcon,
  likeIcon,
  dislikeFillIcon,
  dislikeIcon,
  settingsIcon,
  downloadIcon,
  chevronRightIcon,
  storageFillIcon,
  storageIcon, inboxFillIcon, inboxIcon, myUploadsFillIcon, myUploadsIcon, uploadFillIcon, uploadIcon, tuneFillIcon, tuneIcon} from '../shared/ui/icons';
import { Avatar, cx, Dialog, Icon, Logo, Menu } from '../shared/ui/ui';
import { LanguageSwitch } from './LanguageSwitch';
import { PlayerProvider, usePlayer, usePlayerState } from '../player/context';
import { Ambient } from './Ambient';
import { PlayerBar } from './PlayerBar';
import { SearchBox } from './SearchBox';
import s from './AppShell.module.css';

type NavPath =
  | '/'
  | '/admin/users'
  | '/admin/audit'
  | '/admin/sources'
  | '/admin/library'
  | '/admin/uploads'
  | '/uploads/new'
  | '/uploads/mine'
  | '/admin/settings'
  | '/collection/playlists'
  | '/collection/history'
  | '/collection/likes'
  | '/collection/dislikes';

function NavLink({
  to,
  label,
  icon,
  activeIcon,
  count,
  badge,
}: {
  to: NavPath;
  label: string;
  icon: string;
  activeIcon: string;
  count?: number; // счётчик справа (лайки, дизлайки)
  badge?: number; // яркий бейдж (ждут решения)
}) {
  return (
    <Link to={to} aria-label={label} title={label} className={s.navItem} activeOptions={{ exact: to === '/' }}>
      {({ isActive }) => (
        <>
          <Icon src={isActive ? activeIcon : icon} className={s.navIcon} />
          <span className={s.navLabel}>{label}</span>
          {badge ? <span className={s.navBadge}>{badge > 99 ? '99+' : badge}</span> : null}
          {!badge && count ? <span className={s.navCount}>{count}</span> : null}
        </>
      )}
    </Link>
  );
}

const FOLDED_KEY = 'pipu.nav.folded';
const TOUCHED_KEY = 'pipu.nav.touched';

function readIds(key: string): string[] {
  try {
    const v: unknown = JSON.parse(localStorage.getItem(key) ?? '[]');
    return Array.isArray(v) ? v.filter((x): x is string => typeof x === 'string') : [];
  } catch {
    return [];
  }
}

/** Раздел меню: заголовок сворачивает пункты; явный выбор помнит браузер. Свёрнутый раздел показывает сумму бейджей. */
function NavSection({
  id,
  title,
  badge,
  children,
  defaultFolded = false,
  mobile = false,
}: {
  id: string;
  title: string;
  badge?: number;
  children: ReactNode;
  defaultFolded?: boolean;
  mobile?: boolean;
}) {
  const [folded, setFolded] = useState(() => {
    if (readIds(FOLDED_KEY).includes(id)) return true;
    if (readIds(TOUCHED_KEY).includes(id)) return false;
    return defaultFolded;
  });
  const toggle = () => {
    const next = !folded;
    setFolded(next);
    try {
      const rest = readIds(FOLDED_KEY).filter((x) => x !== id);
      localStorage.setItem(FOLDED_KEY, JSON.stringify(next ? [...rest, id] : rest));
      const touched = readIds(TOUCHED_KEY);
      if (!touched.includes(id)) localStorage.setItem(TOUCHED_KEY, JSON.stringify([...touched, id]));
    } catch {
      // Без хранилища раздел просто не запомнит состояние.
    }
  };
  return (
    <>
      {mobile ? (
        <h3 className={s.navSection}><span className={s.navSectionTitle}>{title}</span></h3>
      ) : (
        <button type="button" className={s.navSection} aria-expanded={!folded} onClick={toggle}>
          <span className={s.navSectionTitle}>{title}</span>
          {folded && badge ? <span className={s.navBadge}>{badge > 99 ? '99+' : badge}</span> : null}
          <Icon src={chevronRightIcon} size={16} className={cx(s.navChevron, !folded && s.navChevronOpen)} />
        </button>
      )}
      <div className={cx(s.navGroup, !mobile && folded && s.navGroupFolded)}>{children}</div>
    </>
  );
}

/** Между выходом и редиректом на /login каркас не рисуется: пользователя уже нет. */
export function AppShell() {
  return useAuthState().status === 'signed_in' ? (
    <PlayerProvider>
      <Shell />
    </PlayerProvider>
  ) : null;
}

function Shell() {
  const { t } = useTranslation();
  const user = useUser();
  const session = useSession();
  const desktop = useDesktop();
  const navigate = useNavigate();
  const name = user.display_name ?? user.username;
  const staff = user.role !== 'user';
  const island = user.ui_prefs.web_player === 'island';
  const searchAt = user.ui_prefs.search_position ?? 'center';
  const search = <SearchBox align={searchAt} collapsible={user.ui_prefs.search_collapse === true} />;
  const counts = useCollectionCounts();
  const reviews = user.reviews_uploads;
  const pending = usePendingUploads(reviews);
  const unseen = useUnseenUploads(staff);
  const [mobileOpen, setMobileOpen] = useState(false);
  const closeMobile = useCallback(() => setMobileOpen(false), []);
  const navigation = (mobile = false) => (
    <>
        <NavLink to="/" label={t('nav.home')} icon={homeIcon} activeIcon={homeFillIcon} />
        <NavSection mobile={mobile} id="collection" title={t('nav.collection')}>
          <NavLink to="/collection/playlists" label={t('playlists.title')} icon={queueIcon} activeIcon={queueIcon} />
          <NavLink to="/collection/history" label={t('nav.history')} icon={historyIcon} activeIcon={historyFillIcon} />
          <NavLink to="/collection/likes" label={t('nav.likes')} icon={likeIcon} activeIcon={likeFillIcon} count={counts.likes} />
          <NavLink
            to="/collection/dislikes"
            label={t('nav.dislikes')}
            icon={dislikeIcon}
            activeIcon={dislikeFillIcon}
            count={counts.dislikes}
          />
        </NavSection>
        {!staff && reviews && (
          <NavLink
            to="/admin/uploads"
            label={t('nav.upload_queue')}
            icon={inboxIcon}
            activeIcon={inboxFillIcon}
            badge={pending}
          />
        )}
        {staff && (
          <NavSection mobile={mobile} id="admin" title={t('nav.admin')} badge={reviews ? pending : undefined} defaultFolded>
            <NavLink to="/admin/users" label={t('nav.users')} icon={groupIcon} activeIcon={groupFillIcon} />
            {user.role === 'admin' && (
              <NavLink to="/admin/sources" label={t('nav.sources')} icon={storageIcon} activeIcon={storageFillIcon} />
            )}
            <NavLink to="/admin/library" label={t('nav.library')} icon={libraryIcon} activeIcon={libraryFillIcon} />
            <NavLink to="/uploads/new" label={t('nav.suggest')} icon={uploadIcon} activeIcon={uploadFillIcon} />
            <NavLink to="/uploads/mine" label={t('nav.my_uploads')} icon={myUploadsIcon} activeIcon={myUploadsFillIcon} badge={unseen} />
            {reviews && (
              <NavLink
                to="/admin/uploads"
                label={t('nav.upload_queue')}
                icon={inboxIcon}
                activeIcon={inboxFillIcon}
                badge={pending}
              />
            )}
            {user.role === 'admin' && (
              <>
                <NavLink to="/admin/settings" label={t('nav.admin_settings')} icon={tuneIcon} activeIcon={tuneFillIcon} />
                <NavLink to="/admin/audit" label={t('nav.audit')} icon={auditIcon} activeIcon={auditFillIcon} />
              </>
            )}
          </NavSection>
        )}
    </>
  );


  return (
    <div className={cx(s.shell, island && s.island)}>
      {user.ui_prefs.ambient !== false && <ShellAmbient />}
      <header className={s.top}>
        <div className={s.topLeft}>
          <Link to="/" className={s.logoLink}>
            <Logo />
          </Link>
          {searchAt === 'left' && search}
        </div>
        <div className={s.topCenter}>{searchAt === 'center' && search}</div>
        <div className={s.topRight}>
          {searchAt === 'right' && search}
          <Menu
            label={t('profile.menu')}
            triggerClassName={s.profileButton}
            trigger={<Avatar name={name} />}
            header={
              <div className={s.profileHead}>
                <Avatar name={name} size={40} />
                <div>
                  <div className={s.profileName}>{name}</div>
                  <div className={s.profileMeta}>
                    @{user.username} · {t(`roles.${user.role}`)}
                  </div>
                </div>
                <LanguageSwitch />
              </div>
            }
            items={[
              { label: t('profile.settings'), icon: settingsIcon, onSelect: () => void navigate({ to: '/settings' }) },
              ...(!desktop
                ? [{ label: t('profile.download_apps'), icon: downloadIcon, onSelect: () => void navigate({ to: '/download' }) }]
                : []),
              { label: t('profile.logout'), icon: logoutIcon, danger: true, onSelect: () => void session.logout() },
            ]}
          />
        </div>
      </header>

      <nav className={s.side} aria-label={t('nav.main')}>{navigation()}</nav>
      <nav className={s.mobileBottom} aria-label={t('nav.main')}>
        <NavLink to="/" label={t('nav.home')} icon={homeIcon} activeIcon={homeFillIcon} />
        <NavLink to="/collection/history" label={t('nav.history')} icon={historyIcon} activeIcon={historyFillIcon} />
        <NavLink to="/collection/likes" label={t('nav.likes')} icon={likeIcon} activeIcon={likeFillIcon} />
        <button type="button" className={s.navItem} aria-label={t('nav.more')}
          aria-haspopup="dialog" aria-expanded={mobileOpen} onClick={() => setMobileOpen(true)}>
          <Icon src={moreIcon} className={s.navIcon} />
          <span className={s.navLabel}>{t('nav.more')}</span>
          {(pending ?? 0) + (unseen ?? 0) > 0 && <span className={s.mobileDot} />}
        </button>
      </nav>
      {mobileOpen && (
        <Dialog title={t('nav.main')} onClose={closeMobile}>
          <nav className={s.mobileMenu} aria-label={t('nav.main')}
            onClick={(e) => { if ((e.target as HTMLElement).closest('a')) closeMobile(); }}>
            {navigation(true)}
          </nav>
        </Dialog>
      )}

      <main className={s.content}>
        <Suspense fallback={null}>
          <Outlet />
        </Suspense>
      </main>

      <PlayerBar variant={island ? 'island' : 'bar'} />
    </div>
  );
}

/** Третье пятно фона — в цвете обложки текущего трека. */
function ShellAmbient() {
  const player = usePlayer();
  const track = usePlayerState().track;
  return <Ambient color={track?.album.cover_colors[0] ?? '#35D3FF'} readAudio={player.readAudio} />;
}

/** Файлов на рассмотрении — бейдж «Очереди» у админа (docs/uploads.md#10). */
function usePendingUploads(enabled: boolean) {
  const session = useSession();
  const q = useQuery({
    queryKey: ['admin-uploads-pending'],
    enabled,
    queryFn: async () =>
      unwrap(
        await session.client.GET('/api/v1/admin/uploads', { params: { query: { status: ['pending_review'], limit: 100 } } }),
      ).items.length,
    refetchInterval: 60_000,
  });
  return q.data;
}

/** Новые решения по своим загрузкам — бейдж «Мои предложения» у персонала. */
function useUnseenUploads(enabled: boolean) {
  const session = useSession();
  const q = useQuery({
    queryKey: ['uploads-unseen'],
    enabled,
    queryFn: async () => unwrap(await session.client.GET('/api/v1/uploads/unseen')).count,
    refetchInterval: 60_000,
  });
  return q.data || undefined;
}