import { unwrap } from '@pipu/core';
import { useMutation, useQuery, useQueryClient } from '@tanstack/react-query';
import { useId } from 'react';
import { useTranslation } from 'react-i18next';

import { useSession, useUser } from '../../app/session';
import { useErrorText } from '../../shared/lib/errors';
import { refreshIcon } from '../../shared/ui/icons';
import { Button, FormError } from '../../shared/ui/ui';
import s from '../page.module.css';
import l from './library.module.css';
import { ScanLine, StatusBadge } from './ScanStatus';

/** Состояние библиотеки: счётчики, хранилища и сканы (admin, moderator), ошибки чтения (admin). */
export function LibraryPage() {
  const { t } = useTranslation(['admin', 'common']);
  const session = useSession();
  const user = useUser();
  const errorText = useErrorText();
  const admin = user.role === 'admin';

  const status = useQuery({
    queryKey: ['library-status'],
    queryFn: async () => unwrap(await session.client.GET('/api/v1/admin/library/status')),
    refetchInterval: (q) => (q.state.data?.sources.some((x) => x.scan?.running) ? 2000 : 15000),
  });
  const errors = useQuery({
    queryKey: ['library-errors'],
    enabled: admin,
    queryFn: async () => unwrap(await session.client.GET('/api/v1/admin/library/errors', { params: { query: { limit: 50 } } })),
  });
  const reindex = useMutation({
    mutationFn: async () => unwrap(await session.client.POST('/api/v1/admin/search/reindex')),
  });
  const queryClient = useQueryClient();
  const retry = useMutation({
    mutationFn: async () => unwrap(await session.client.POST('/api/v1/admin/library/analysis/retry')),
    onSuccess: () => void queryClient.invalidateQueries({ queryKey: ['library-status'] }),
  });
  const d = status.data;
  const tiles = d
    ? ([
        ['artists', d.artists],
        ['albums', d.albums],
        ['tracks', d.tracks],
        ['files', d.files],
        ['missing', d.missing_files],
        ['errors', d.file_errors],
      ] as const)
    : [];

  return (
    <div className={s.page}>
      <div className={s.head}>
        <div>
          <h1>{t('library.title')}</h1>
          <p className={s.subtitle}>{t('library.subtitle')}</p>
        </div>
        {admin && (
          <Button icon={refreshIcon} busy={reindex.isPending} onClick={() => reindex.mutate()}>
            {reindex.isSuccess ? t('library.reindex_started') : t('library.reindex')}
          </Button>
        )}
      </div>
      <FormError>{status.error || reindex.error ? errorText(status.error ?? reindex.error) : null}</FormError>
      <div className={l.tiles}>
        {tiles.map(([k, v]) => (
          <div key={k} className={l.tile}>
            <span className={l.tileValue}>{v.toLocaleString()}</span>
            <span className={l.tileLabel}>{t(`library.${k}`)}</span>
          </div>
        ))}
      </div>
      {d && (
        <section className={s.section}>
          <h2>{t('library.analysis')}</h2>
          <ScanLineBar
            done={d.analysis.done}
            total={d.analysis.done + d.analysis.queued + d.analysis.running + d.analysis.failed}
            label={t('library.analysis_progress', {
              done: d.analysis.done,
              total: d.analysis.done + d.analysis.queued + d.analysis.running + d.analysis.failed,
            })}
          />
          {d.analysis.failed > 0 && (
            <div className={l.retryRow}>
              <span className={l.scanError}>
                {t('library.analysis_failed', { count: d.analysis.failed })}
                {d.analysis.top_error && <span className={l.errorDetail}>{d.analysis.top_error}</span>}
              </span>
              {admin && (
                <Button variant="secondary" icon={refreshIcon} busy={retry.isPending} onClick={() => retry.mutate()}>
                  {t('library.analysis_retry')}
                </Button>
              )}
            </div>
          )}
          {d.analysis.analyzer_ver && <span className={l.scanSummary}>{t('library.analyzer', { ver: d.analysis.analyzer_ver })}</span>}
        </section>
      )}
      {d && (
        <section className={s.section}>
          <h2>{t('library.wave')}</h2>
          <div className={l.tiles}>
            {(
              [
                ['wave_served', d.wave.served.toLocaleString()],
                ['wave_sessions', d.wave.sessions.toLocaleString()],
                ['wave_listen', pct(d.wave.listen_through_rate)],
                ['wave_early_skip', pct(d.wave.early_skip_rate)],
                ['wave_likes', d.wave.like_rate === null ? '—' : d.wave.like_rate.toFixed(1)],
              ] as const
            ).map(([k, v]) => (
              <div key={k} className={l.tile}>
                <span className={l.tileValue}>{v}</span>
                <span className={l.tileLabel}>{t(`library.${k}`)}</span>
              </div>
            ))}
          </div>
          {d.wave.by_model.length > 1 && (
            <div className={s.tableWrap}>
              <table className={s.table}>
                <caption className={s.muted}>{t('library.wave_by_model')}</caption>
                <thead>
                  <tr>
                    <th scope="col">{t('library.wave_model')}</th>
                    <th scope="col">{t('library.wave_served')}</th>
                    <th scope="col">{t('library.wave_listen')}</th>
                    <th scope="col">{t('library.wave_early_skip')}</th>
                    <th scope="col">{t('library.wave_likes')}</th>
                  </tr>
                </thead>
                <tbody>
                  {d.wave.by_model.map((m) => (
                    <tr key={m.model_ver}>
                      <td>{m.model_ver || '—'}</td>
                      <td>{m.served.toLocaleString()}</td>
                      <td>{pct(m.listen_through_rate)}</td>
                      <td>{pct(m.early_skip_rate)}</td>
                      <td>{m.like_rate === null ? '—' : m.like_rate.toFixed(1)}</td>
                    </tr>
                  ))}
                </tbody>
              </table>
            </div>
          )}
        </section>
      )}
      {d && d.sources.length > 0 && (
        <section className={s.section}>
          <h2>{t('library.sources')}</h2>
          {d.sources.map((src) => (
            <div key={src.id} className={l.cardFoot}>
              <div className={l.cardTitle}>
                {src.name} <StatusBadge status={src.status} />
              </div>
              <ScanLine scan={src.scan} lastScanAt={src.last_scan_at} />
            </div>
          ))}
        </section>
      )}
      {admin && errors.data && errors.data.items.length > 0 && (
        <section className={s.section}>
          <h2>{t('library.error_files')}</h2>
          {errors.data.items.map((e) => (
            <div key={e.file_id} className={l.cardFoot}>
              <span className={l.location}>{e.rel_path}</span>
              <span className={l.scanError}>{e.error}</span>
            </div>
          ))}
        </section>
      )}
    </div>
  );
}

const pct = (v: number | null) => (v === null ? '—' : `${Math.round(v * 100)}%`);

function ScanLineBar({ done, total, label }: { done: number; total: number; label: string }) {
  const value = total > 0 ? Math.round((done / total) * 100) : 0;
  const id = useId();
  return (
    <div className={l.scan}>
      <div className={l.scanText} id={id}>
        {label}
      </div>
      <div className={l.bar} role="progressbar" aria-labelledby={id} aria-valuenow={value} aria-valuemin={0} aria-valuemax={100}>
        <span style={{ width: `${value}%` }} />
      </div>
    </div>
  );
}