import { useEffect, useRef, useState } from 'react';

import { useEscapeKey } from '@/lib/hooks';
import { ImApiError } from '@/lib/api/client';
import { requestSecurityChallenge, verifySecurityChallenge } from '@/lib/api/security';
import { useSecurityChallengeStore } from '@/stores/securityChallenge';

/** Mounted once at the app root (App.tsx), same placement/pattern as ConfirmDialogRoot -- renders
 *  whatever `requestActionToken()` (stores/securityChallenge.ts) most recently asked for: the
 *  protocol's sensitive-action SMS re-verification (docs/IM-前后端对接文档.md:762-766), needed before
 *  a group can actually be dissolved (or its ownership transferred) -- both require `X-Action-Token`,
 *  and there was previously no UI anywhere in this app that could produce one. */
export function SecurityChallengeModal() {
  const pending = useSecurityChallengeStore((s) => s.pending);
  const respond = useSecurityChallengeStore((s) => s.respond);
  const [challengeId, setChallengeId] = useState('');
  const [phoneMask, setPhoneMask] = useState('');
  const [code, setCode] = useState('');
  const [seconds, setSeconds] = useState(0);
  const [busy, setBusy] = useState(false);
  const [error, setError] = useState('');
  const timerRef = useRef<number | undefined>(undefined);
  useEscapeKey(() => respond(null));

  const tick = (initial: number) => {
    window.clearInterval(timerRef.current);
    setSeconds(initial);
    timerRef.current = window.setInterval(() => {
      setSeconds((s) => {
        if (s <= 1) {
          window.clearInterval(timerRef.current);
          return 0;
        }
        return s - 1;
      });
    }, 1000);
  };

  // Fires the first SMS the moment the modal opens -- the doc's own flow has no separate "get code"
  // click for this endpoint (unlike VerificationCodeButton's register/reset-password scenes), since
  // the phone number isn't something the user enters here at all (read server-side from the login
  // identity), so there's nothing to wait on the user to fill in first.
  useEffect(() => {
    window.clearInterval(timerRef.current);
    setChallengeId('');
    setCode('');
    setError('');
    setSeconds(0);
    if (!pending) return undefined;
    let cancelled = false;
    requestSecurityChallenge(pending.scene)
      .then((data) => {
        if (cancelled) return;
        setChallengeId(data.challenge_id);
        setPhoneMask(data.phone_mask);
        tick(data.resend_after_seconds || 60);
      })
      .catch((err) => {
        if (cancelled) return;
        setError(err instanceof ImApiError ? err.message : '验证码发送失败，请重试');
      });
    return () => {
      cancelled = true;
      window.clearInterval(timerRef.current);
    };
    // eslint-disable-next-line react-hooks/exhaustive-deps
  }, [pending?.scene]);

  if (!pending) return null;

  const resend = () => {
    if (busy || seconds > 0) return;
    setError('');
    setBusy(true);
    requestSecurityChallenge(pending.scene)
      .then((data) => {
        setChallengeId(data.challenge_id);
        setPhoneMask(data.phone_mask);
        tick(data.resend_after_seconds || 60);
      })
      .catch((err) => setError(err instanceof ImApiError ? err.message : '验证码发送失败，请重试'))
      .finally(() => setBusy(false));
  };

  const submit = async () => {
    if (!challengeId || !/^\d{6}$/.test(code)) return setError('请输入 6 位验证码');
    setBusy(true);
    setError('');
    try {
      const verified = await verifySecurityChallenge(challengeId, code);
      respond(verified.action_token);
    } catch (err) {
      setError(err instanceof ImApiError ? err.message : '验证码错误或已过期');
      setBusy(false);
    }
  };

  return (
    <div className="fixed inset-0 z-[100] flex items-center justify-center bg-[#22262d]/25" onClick={() => respond(null)}>
      <div className="w-[340px] rounded-xl bg-white p-5 shadow-modal" onClick={(e) => e.stopPropagation()}>
        <strong className="mb-2 block text-base font-semibold text-text-heading">安全验证</strong>
        <p className="m-0 text-sm leading-relaxed text-text-body">
          即将{pending.actionDescription}，请验证手机号{phoneMask ? ` ${phoneMask}` : ''} 收到的短信验证码
        </p>
        <div className="mt-4 flex items-center gap-2">
          <input
            value={code}
            onChange={(e) => setCode(e.target.value.replace(/\D/g, '').slice(0, 6))}
            placeholder="请输入 6 位验证码"
            inputMode="numeric"
            autoFocus
            className="h-9 min-w-0 flex-1 rounded-lg border border-border-panel px-3 text-sm outline-none focus:border-accent"
          />
          <button
            type="button"
            onClick={resend}
            disabled={busy || seconds > 0 || !challengeId}
            className="h-9 w-28 flex-none rounded-lg bg-accent-soft-bg text-sm text-accent disabled:bg-[#e6e9ee] disabled:text-text-tertiary-3"
          >
            {seconds > 0 ? `重新获取(${seconds}s)` : '重新获取'}
          </button>
        </div>
        {error ? <p className="m-0 mt-2 text-xs text-danger-text">{error}</p> : null}
        <div className="mt-5 flex justify-end gap-3">
          <button
            type="button"
            onClick={() => respond(null)}
            className="grid h-9 place-items-center rounded-lg border border-[#d5d9df] px-4 text-sm text-text-secondary"
          >
            取消
          </button>
          <button
            type="button"
            onClick={submit}
            disabled={busy || !challengeId || code.length !== 6}
            className="grid h-9 place-items-center rounded-lg bg-btn px-4 text-sm font-medium text-white disabled:opacity-50"
          >
            {busy ? '验证中…' : '确定'}
          </button>
        </div>
      </div>
    </div>
  );
}