import { useState } from 'react';

import { Link, Navigate, useNavigate } from 'react-router-dom';

import { PasswordInput } from '@/features/auth/components/PasswordInput';
import { Toast } from '@/features/auth/components/Toast';
import { VerificationCodeButton } from '@/features/auth/components/VerificationCodeButton';
import { confirmPasswordReset, verifyPasswordResetCode } from '@/lib/api/auth';
import { ImApiError } from '@/lib/api/client';
import { useSessionStore } from '@/stores/session';

const PHONE_RE = /^\d{11}$/;

export function ResetPasswordPage() {
  const navigate = useNavigate();
  const tenant = useSessionStore((s) => s.tenant);

  const [phone, setPhone] = useState('');
  const [code, setCode] = useState('');
  const [password, setPassword] = useState('');
  const [confirm, setConfirm] = useState('');
  const [challengeId, setChallengeId] = useState('');
  const [error, setError] = useState('');
  const [submitting, setSubmitting] = useState(false);
  const [toast, setToast] = useState('');

  if (!tenant) return <Navigate to="/tenant" replace />;

  const submit = async (e: React.FormEvent) => {
    e.preventDefault();
    if (!PHONE_RE.test(phone)) return setError('请输入 11 位手机号');
    if (!challengeId || !/^\d{6}$/.test(code)) return setError('请先获取并输入 6 位验证码');
    // Matches Register's rule (>= 8, no upper bound -- the backend's checkPasswordPolicy only
    // enforces a minimum length).
    if (password.length < 8) return setError('密码至少 8 位，需包含字母和数字');
    if (password !== confirm) return setError('两次输入的密码不一致');

    setSubmitting(true);
    setError('');
    try {
      const verified = await verifyPasswordResetCode(challengeId, code);
      await confirmPasswordReset(verified.reset_token, password);
      setToast('密码修改成功，请重新登录');
      window.setTimeout(() => navigate('/login'), 1200);
    } catch (err) {
      setError(err instanceof ImApiError ? err.message : '验证码错误或已过期');
      setSubmitting(false);
    }
  };

  return (
    <div className="flex h-dvh w-full items-center justify-center bg-surface-page px-6">
      <form onSubmit={submit} className="flex w-full max-w-[380px] flex-col gap-4">
        <Link to="/login" className="flex items-center gap-1 text-sm text-text-secondary no-underline">
          <span className="material-icons text-[16px]">arrow_back_ios_new</span>
          返回登录
        </Link>
        <div className="flex flex-col gap-1">
          <h1 className="m-0 text-[22px] font-bold text-text-title">重置密码</h1>
          <p className="m-0 text-sm text-text-tertiary-1">
            通过已绑定的手机号验证身份。未绑定手机号的账号请联系企业管理员重置。
          </p>
        </div>
        {error ? (
          <div className="rounded-lg bg-error-strip-bg px-3 py-2.5 text-sm text-error-strip-text">{error}</div>
        ) : null}

        <label className="flex h-[50px] items-center gap-2 rounded-lg bg-surface-input px-3.5 has-focus:border has-focus:border-focus-border has-focus:shadow-focus-ring">
          <span className="text-[15px] text-text-tertiary-2">+86</span>
          <input
            value={phone}
            onChange={(e) => setPhone(e.target.value.replace(/\D/g, '').slice(0, 11))}
            placeholder="请输入手机号"
            inputMode="numeric"
            className="w-full bg-transparent text-[15px] outline-none"
          />
        </label>

        <div className="flex gap-2">
          <input
            value={code}
            onChange={(e) => setCode(e.target.value.replace(/\D/g, '').slice(0, 6))}
            placeholder="短信验证码"
            inputMode="numeric"
            className="h-[50px] flex-1 rounded-lg bg-surface-input px-3.5 text-[15px] outline-none"
          />
          <VerificationCodeButton phone={phone} scene="reset_password" onChallenge={setChallengeId} onError={setError} />
        </div>

        <PasswordInput value={password} onChange={setPassword} placeholder="新密码" autoComplete="new-password" />
        <PasswordInput value={confirm} onChange={setConfirm} placeholder="再次输入新密码" autoComplete="new-password" />

        <button
          type="submit"
          disabled={!phone || !code || !password || !confirm || submitting}
          className="h-[50px] rounded-lg bg-btn text-base font-medium text-white shadow-btn disabled:bg-btn-disabled disabled:shadow-none"
        >
          {submitting ? '提交中…' : '确认重置'}
        </button>
      </form>
      <Toast message={toast} onDone={() => setToast('')} />
    </div>
  );
}