import { useEffect, useMemo, useRef, useState } from 'preact/hooks';
import { Clipboard, Globe } from 'lucide-preact';
import { calcTotpNow } from '@/lib/crypto';
import { t } from '@/lib/i18n';
import type { Cipher } from '@/lib/types';

interface TotpCodesPageProps {
  ciphers: Cipher[];
  loading: boolean;
  onNotify: (type: 'success' | 'error', text: string) => void;
}

const TOTP_PERIOD_SECONDS = 30;
const TOTP_RING_RADIUS = 14;
const TOTP_RING_CIRCUMFERENCE = 2 * Math.PI * TOTP_RING_RADIUS;

function formatTotp(code: string): string {
  if (!code || code.length < 6) return code;
  return `${code.slice(0, 3)} ${code.slice(3, 6)}`;
}

function firstCipherUri(cipher: Cipher): string {
  const uris = cipher.login?.uris || [];
  for (const uri of uris) {
    const raw = uri.decUri || uri.uri || '';
    if (raw.trim()) return raw.trim();
  }
  return '';
}

function hostFromUri(uri: string): string {
  if (!uri.trim()) return '';
  try {
    const normalized = /^https?:\/\//i.test(uri) ? uri : `https://${uri}`;
    return new URL(normalized).hostname || '';
  } catch {
    return '';
  }
}

function TotpListIcon({ cipher }: { cipher: Cipher }) {
  const uri = firstCipherUri(cipher);
  const host = hostFromUri(uri);
  const [errored, setErrored] = useState(false);

  if (host && !errored) {
    return (
      <img
        className="list-icon"
        src={`/icons/${host}/icon.png?v=2`}
        alt=""
        loading="lazy"
        onError={() => setErrored(true)}
      />
    );
  }

  return (
    <span className="list-icon-fallback">
      <Globe size={18} />
    </span>
  );
}

export default function TotpCodesPage(props: TotpCodesPageProps) {
  const [totpMap, setTotpMap] = useState<Record<string, { code: string; remain: number } | null>>({});
  const [columnCount, setColumnCount] = useState(1);
  const listRef = useRef<HTMLDivElement | null>(null);

  async function copyToClipboard(value: string): Promise<void> {
    if (!value.trim()) return;
    await navigator.clipboard.writeText(value);
    props.onNotify('success', t('txt_code_copied'));
  }

  const totpItems = useMemo(
    () =>
      props.ciphers
        .filter((cipher) => {
          const isDeleted = !!(cipher.deletedDate || (cipher as { deletedAt?: string | null }).deletedAt);
          return !isDeleted && !!cipher.login?.decTotp;
        })
        .sort((a, b) => {
          const nameA = (a.decName || a.name || '').trim().toLowerCase();
          const nameB = (b.decName || b.name || '').trim().toLowerCase();
          return nameA.localeCompare(nameB);
        }),
    [props.ciphers]
  );

  useEffect(() => {
    if (!totpItems.length) {
      setTotpMap({});
      return;
    }
    let stopped = false;
    let timer = 0;
    const tick = async () => {
      const entries = await Promise.all(
        totpItems.map(async (cipher) => {
          try {
            const next = await calcTotpNow(cipher.login?.decTotp || '');
            return [cipher.id, next] as const;
          } catch {
            return [cipher.id, null] as const;
          }
        })
      );
      if (!stopped) setTotpMap(Object.fromEntries(entries));
    };
    void tick();
    timer = window.setInterval(() => void tick(), 1000);
    return () => {
      stopped = true;
      window.clearInterval(timer);
    };
  }, [totpItems]);

  useEffect(() => {
    const element = listRef.current;
    if (!element) return;

    const gap = 10;
    const minCardWidth = 320;
    const maxColumns = 4;

    const updateColumns = () => {
      const width = element.clientWidth;
      if (!width) return;
      const next = Math.max(1, Math.min(maxColumns, Math.floor((width + gap) / (minCardWidth + gap))));
      setColumnCount(next);
    };

    updateColumns();
    const observer = new ResizeObserver(() => updateColumns());
    observer.observe(element);
    return () => observer.disconnect();
  }, []);

  return (
    <div className="totp-codes-page">
      <div className="card">
        <div className="section-head">
          <h3 className="detail-title">{t('txt_verification_code')}</h3>
        </div>
        <div
          ref={listRef}
          className="totp-codes-list"
          style={{ '--totp-columns': String(columnCount) } as Record<string, string>}
        >
          {!totpItems.length && !props.loading && <div className="empty">{t('txt_no_verification_codes')}</div>}
          {totpItems.map((cipher) => {
            const live = totpMap[cipher.id] || null;
            const name = cipher.decName || cipher.name || t('txt_no_name');
            const username = cipher.login?.decUsername || '';
            return (
              <div key={cipher.id} className="totp-code-row">
                <div className="totp-code-info">
                  <div className="list-icon-wrap">
                    <TotpListIcon cipher={cipher} />
                  </div>
                  <div className="totp-code-meta">
                    <div className="totp-code-name" title={name}>{name}</div>
                    <div className="totp-code-username" title={username}>{username || t('txt_no_username')}</div>
                  </div>
                </div>
                <div className="totp-code-main">
                  <strong>{live ? formatTotp(live.code) : t('txt_text_3')}</strong>
                  <div
                    className="totp-timer"
                    title={t('txt_refresh_in_seconds_s', { seconds: live ? live.remain : 0 })}
                    aria-label={t('txt_refresh_in_seconds_s', { seconds: live ? live.remain : 0 })}
                  >
                    <svg viewBox="0 0 36 36" className="totp-ring" role="presentation" aria-hidden="true">
                      <circle className="totp-ring-track" cx="18" cy="18" r={TOTP_RING_RADIUS} />
                      <circle
                        className="totp-ring-progress"
                        cx="18"
                        cy="18"
                        r={TOTP_RING_RADIUS}
                        style={{
                          strokeDasharray: `${TOTP_RING_CIRCUMFERENCE} ${TOTP_RING_CIRCUMFERENCE}`,
                          strokeDashoffset: String(
                            TOTP_RING_CIRCUMFERENCE -
                              TOTP_RING_CIRCUMFERENCE *
                                (Math.max(0, Math.min(TOTP_PERIOD_SECONDS, live?.remain ?? 0)) / TOTP_PERIOD_SECONDS)
                          ),
                        }}
                      />
                    </svg>
                    <span className="totp-timer-value">{live ? live.remain : 0}</span>
                  </div>
                  <button type="button" className="btn btn-secondary small totp-copy-btn" onClick={() => void copyToClipboard(live?.code || '')} aria-label={t('txt_copy')}>
                    <Clipboard size={14} className="btn-icon" />
                  </button>
                </div>
              </div>
            );
          })}
        </div>
      </div>
    </div>
  );
}