import { unwrap } from '@pipu/core';
import { useMutation, useQuery, useQueryClient } from '@tanstack/react-query';
import { Link, useNavigate } from '@tanstack/react-router';
import { useState, type MouseEvent } from 'react';
import { useTranslation } from 'react-i18next';
import { useSession } from '../app/session';
import { Cover, TrackList } from '../entities/catalog';
import { PlaylistEditor, playlistInput, usePlaylist, usePlaylists, type Playlist } from '../entities/playlists';
import type { components } from '@pipu/api-client';
import { usePlayer } from '../player/context';
import { useErrorText } from '../shared/lib/errors';
import { playlistShareUrl } from '@pipu/core';
import { desktopHandle } from '../desktop';
import { useMusicShare } from '../features/social/Social';
import { formatDuration } from '../shared/lib/format';
import { Button, Dialog, EmptyState, Field, FormError, Icon, PageSkeleton } from '../shared/ui/ui';
import { playIcon, playlistAddIcon, searchIcon, shuffleIcon, shareIcon } from '../shared/ui/icons';
import c from './catalog.module.css';
import s from './page.module.css';
import p from './playlists.module.css';

export function PlaylistsPage() {
  const { t } = useTranslation();
  const list = usePlaylists();
  const errorText = useErrorText();
  const navigate = useNavigate();
  const [create, setCreate] = useState(false);
  const [search, setSearch] = useState('');
  const items = list.data?.items.filter(x => x.name.toLocaleLowerCase().includes(search.toLocaleLowerCase())) ?? [];
  return <div className={s.page}>
    <header className={s.toolbar}><h1>{t('playlists.title')}</h1><Button variant="primary" onClick={() => setCreate(true)}>{t('playlists.create')}</Button></header>
    <Field label={t('playlists.search')} value={search} onChange={setSearch} type="search" />
    <FormError>{list.error ? errorText(list.error) : null}</FormError>
    {list.isPending && <PageSkeleton />}
    {list.isSuccess && !items.length && (
      <EmptyState
        icon={search ? searchIcon : playlistAddIcon}
        action={!search ? <Button variant="primary" onClick={() => setCreate(true)}>{t('playlists.create')}</Button> : undefined}
      >
        {t(search ? 'playlists.no_results' : 'playlists.empty')}
      </EmptyState>
    )}
    <div className={p.grid}>{items.map(item => <PlaylistCard key={item.id} item={item} />)}</div>
    {create && <PlaylistEditor onClose={() => setCreate(false)} onSaved={item => { setCreate(false); void navigate({ to: '/playlist/$id', params: { id: item.id } }); }} />}
  </div>;
}

export function PlaylistPage({ id, shared = false }: { id: string; shared?: boolean }) {
  const { t } = useTranslation();
  const query = usePlaylist(id, shared);
  const errorText = useErrorText();
  return <div className={s.page}>
    <Link to="/collection/playlists">← {t('playlists.title')}</Link>
    <FormError>{query.error ? errorText(query.error) : null}</FormError>
    {query.isPending && <PageSkeleton />}
    {query.data && !query.isError && <PlaylistDetail key={id} playlist={query.data} readOnly={shared} shareId={shared ? id : undefined} />}
  </div>;
}

export function ActivityPlaylistPage({ userId }: { userId: string }) {
  const session = useSession();
  const errorText = useErrorText();
  const { t } = useTranslation();
  const query = useQuery({ queryKey: ['activity-playlist', session.state.status === 'signed_in' ? session.state.user.id : '', userId], queryFn: async () => unwrap(await session.client.GET('/api/v1/social/activity/{userId}/playlist', { params: { path: { userId } } })), staleTime: 0, refetchInterval: 15_000 });
  return <div className={s.page}>
    <Link to="/friends">← {t('social.title')}</Link>
    <FormError>{query.error ? errorText(query.error) : null}</FormError>
    {query.isPending && <PageSkeleton />}
    {query.data && !query.isError && <PlaylistDetail key={query.data.id} playlist={query.data} readOnly activity />}
  </div>;
}

function PlaylistDetail({ playlist, readOnly = false, shareId, activity = false }: { playlist: Playlist; readOnly?: boolean; shareId?: string; activity?: boolean }) {
  const openShare = useMusicShare();
  const { t } = useTranslation();
  const session = useSession();
  const cache = useQueryClient();
  const player = usePlayer();
  const navigate = useNavigate();
  const errorText = useErrorText();
  const [edit, setEdit] = useState(false);
  const [remove, setRemove] = useState(false);
  const [manage, setManage] = useState(false);
  const sharing = useMutation({ mutationFn: async () => {
    let token = shareId ?? playlist.share_id;
    if (!readOnly) {
      token = unwrap(await session.client.POST('/api/v1/me/playlists/{id}/share', { params: { path: { id: playlist.id } } })).share_id;
      cache.setQueryData<Playlist>(['playlists', playlist.id], current => current ? { ...current, share_id: token } : current);
    }
    if (!token) throw new Error('Share link unavailable');
    openShare({ attachment: { kind: 'playlist', id: token, title: playlist.name }, url: playlistShareUrl(desktopHandle()?.server ?? window.location.origin, token) });
  } });
  const revoke = useMutation({ mutationFn: async () => unwrap(await session.client.DELETE('/api/v1/me/playlists/{id}/share', { params: { path: { id: playlist.id } } })),
    onSuccess: () => { cache.setQueryData<Playlist>(['playlists', playlist.id], current => current ? { ...current, share_id: null } : current); cache.removeQueries({ queryKey: ['shared-playlists', playlist.share_id] }); } });

  const context = { type: 'collection' as const, id: playlist.id, label: playlist.name };
  const save = useMutation({ mutationFn: async (ids: string[]) => unwrap(await session.client.PUT('/api/v1/me/playlists/{id}', {
    params: { path: { id: playlist.id } }, body: { ...playlistInput(playlist), track_ids: ids },
  })), onSuccess: data => { cache.setQueryData(['playlists', playlist.id], data); void cache.invalidateQueries({ queryKey: ['playlists'] }); },
  onError: () => { void cache.invalidateQueries({ queryKey: ['playlists'] }); } });
  const deletion = useMutation({ mutationFn: async () => unwrap(await session.client.DELETE('/api/v1/me/playlists/{id}', { params: { path: { id: playlist.id } } })),
    onSuccess: () => { cache.removeQueries({ queryKey: ['playlists', playlist.id] }); void cache.invalidateQueries({ queryKey: ['playlists'] }); void navigate({ to: '/collection/playlists' }); } });
  const play = (shuffle: boolean) => {
    const tracks = playlist.tracks.filter(x => x.available);
    if (shuffle) for (let i = tracks.length - 1; i > 0; i--) { const j = Math.floor(Math.random() * (i + 1)); [tracks[i], tracks[j]] = [tracks[j]!, tracks[i]!]; }
    if (tracks.length) player.playList(tracks, 0, context);
  };
  const move = (index: number, delta: number) => {
    const ids = playlist.tracks.map(x => x.id);
    [ids[index], ids[index + delta]] = [ids[index + delta]!, ids[index]!];
    save.mutate(ids);
  };
  return <>
    <header className={c.colHero}>
      <Cover album={playlist.tracks[0]?.album ?? playlist} size={144} />
      <div className={c.heroText}><span className={c.kicker}>{t(readOnly || playlist.share_id ? 'playlists.shared' : 'playlists.private')}</span><h1 className={c.colTitle}>{playlist.name}</h1>
        <p className={p.description}>{playlist.description}</p>
        <span>{t('catalog.track_count', { count: playlist.track_count })} · {formatDuration(playlist.duration_ms)}</span>
      </div>
    </header>
    <div className={s.toolbar}>
      <Button variant="primary" icon={playIcon} disabled={!playlist.tracks.some(x => x.available)} onClick={() => play(false)}>{t('collection.play_all')}</Button>
      <Button icon={shuffleIcon} disabled={!playlist.tracks.some(x => x.available)} onClick={() => play(true)}>{t('collection.shuffle')}</Button>
      {!activity && <Button icon={shareIcon} busy={sharing.isPending} disabled={revoke.isPending} onClick={() => sharing.mutate()}>{t('playlists.share')}</Button>}
      {!readOnly && <>
      <Button disabled={save.isPending} onClick={() => setEdit(true)}>{t('playlists.edit')}</Button>
      <Button aria-pressed={manage} onClick={() => setManage(!manage)}>{t('playlists.manage')}</Button>
      <Button variant="ghost" disabled={save.isPending} onClick={() => setRemove(true)}>{t('playlists.delete')}</Button>
      {playlist.share_id && <Button variant="ghost" busy={revoke.isPending} disabled={sharing.isPending} onClick={() => revoke.mutate()}>{t('playlists.revoke_share')}</Button>}
      </>}
    </div>
    {!readOnly && <p>{t('playlists.share_hint')}</p>}
    <FormError>{sharing.error ? t('player.share_error') : revoke.error ? errorText(revoke.error) : null}</FormError>
    <FormError>{save.error ? errorText(save.error) : null}</FormError>
    {!playlist.tracks.length && (
      <EmptyState icon={playlistAddIcon} action={<Link to="/search" search={{ q: '' }}>{t('playlists.find_tracks')}</Link>}>
        {t('playlists.empty_tracks')}
      </EmptyState>
    )}
    <TrackList tracks={playlist.tracks} showAlbum context={context} lead={(_, i) => String(i + 1)}
      actions={!readOnly && manage ? (track, i) => <span className={p.actions}>
        <button type="button" disabled={i === 0 || save.isPending} aria-label={t('playlists.move_up', { name: track.title })} onClick={() => move(i, -1)}>↑</button>
        <button type="button" disabled={i === playlist.tracks.length - 1 || save.isPending} aria-label={t('playlists.move_down', { name: track.title })} onClick={() => move(i, 1)}>↓</button>
        <button type="button" disabled={save.isPending} aria-label={t('playlists.remove_track', { name: track.title })} onClick={() => save.mutate(playlist.tracks.filter(x => x.id !== track.id).map(x => x.id))}>×</button>
      </span> : undefined} />
    {!readOnly && edit && <PlaylistEditor playlist={playlist} onClose={() => setEdit(false)} onSaved={() => setEdit(false)} />}
    {!readOnly && remove && (
      <Dialog
        title={t('playlists.delete')}
        onClose={() => {
          if (!deletion.isPending) setRemove(false);
        }}
        footer={
          <>
            <Button disabled={deletion.isPending} onClick={() => setRemove(false)}>{t('form.cancel')}</Button>
            <Button variant="danger" busy={deletion.isPending} onClick={() => deletion.mutate()}>{t('playlists.delete')}</Button>
          </>
        }
      >
        <p>{t('playlists.delete_confirm', { name: playlist.name })}</p>
        <FormError>{deletion.error ? errorText(deletion.error) : null}</FormError>
      </Dialog>
    )}
  </>;
}

function PlaylistCard({ item }: { item: components['schemas']['PlaylistSummary'] }) {
  const { t } = useTranslation();
  const session = useSession();
  const player = usePlayer();
  const play = (e: MouseEvent) => {
    e.preventDefault();
    e.stopPropagation();
    void (async () => {
      const full = unwrap(await session.client.GET('/api/v1/me/playlists/{id}', { params: { path: { id: item.id } } }));
      const tracks = full.tracks.filter((x) => x.available);
      if (tracks.length) player.playList(tracks, 0, { type: 'collection', id: item.id, label: item.name });
    })();
  };
  return (
    <Link to="/playlist/$id" params={{ id: item.id }} className={p.card}>
      <span className={p.coverWrap}>
        <Cover album={item} size="100%" />
        {item.track_count > 0 && (
          <button type="button" className={p.play} aria-label={t('catalog.play')} onClick={play}>
            <Icon src={playIcon} size={22} />
          </button>
        )}
      </span>
      <strong>{item.name}</strong>
      <span>{t('catalog.track_count', { count: item.track_count })} · {formatDuration(item.duration_ms)}</span>
      {item.description && <span className={p.description}>{item.description}</span>}
    </Link>
  );
}