import { useEffect, useRef, useState, type RefObject } from 'react';
import { Link, useNavigate, useSearchParams } from 'react-router-dom';
import AppImage from '@dukang/shared-ui/AppImage';
import { isWxAuthorizeEnabled } from '@dukang/shared-types';
import { stripOAuthParamsFromLocation } from '@dukang/weixin-sdk';
import { useStoreSession } from '../contexts/StoreSessionContext';
import { getLastPhone, getStoreProfile, hasShopWxSession, request, saveAuth, type ShopSessionPayload } from '../lib/api';
import { routeAfterShopLogin } from './SelectStorePage';
import {
  bindShopWechatAfterSmsLogin,
  fetchClientConfig,
  handleShopWechatCallback,
  handleShopWechatLoginResult,
  loginShopWithWechat,
} from '../lib/wechat-auth';
import { isWechatEnv } from '../lib/weixin';

function maskPhone(phone: string) {
  if (phone.length < 7) return phone;
  return `${phone.slice(0, 3)} **** ${phone.slice(-4)}`;
}

function formatWechatError(e: unknown): string {
  const text = e instanceof Error ? e.message : '微信登录失败';
  if (text.includes('首次登录') || text.includes('手机验证码')) {
    return '该微信尚未绑定门店账号，请先使用手机验证码登录，登录后将自动关联微信';
  }
  return text;
}

function ShopAgreementCheckbox({
  agreed,
  onChange,
  labelRef,
}: {
  agreed: boolean;
  onChange: (next: boolean) => void;
  labelRef?: RefObject<HTMLLabelElement | null>;
}) {
  return (
    <label className="shop-login-agreement" ref={labelRef}>
      <input
        type="checkbox"
        checked={agreed}
        onChange={(e) => onChange(e.target.checked)}
      />
      <span>
        我已阅读并同意
        <Link to="/legal/user-agreement" onClick={(e) => e.stopPropagation()}>
          《用户协议》
        </Link>
        与
        <Link to="/legal/privacy-policy" onClick={(e) => e.stopPropagation()}>
          《隐私政策》
        </Link>
      </span>
    </label>
  );
}

export default function LoginPage() {
  const navigate = useNavigate();
  const { applySession } = useStoreSession();
  const [params, setSearchParams] = useSearchParams();
  const quick = params.get('quick') === '1';
  const savedProfile = getStoreProfile();
  const [phone, setPhone] = useState(getLastPhone());
  const [code, setCode] = useState('');
  const [agreed, setAgreed] = useState(false);
  const [loading, setLoading] = useState(false);
  const [wxLoading, setWxLoading] = useState(false);
  const [msg, setMsg] = useState('');
  const [codeCooldown, setCodeCooldown] = useState(0);
  const [wxAuthorize, setWxAuthorize] = useState(false);
  const agreementRef = useRef<HTMLLabelElement>(null);

  useEffect(() => {
    fetchClientConfig()
      .then((config) => setWxAuthorize(isWxAuthorizeEnabled(config)))
      .catch(() => setWxAuthorize(false));
  }, []);

  useEffect(() => {
    if (!isWechatEnv() || !wxAuthorize || !params.get('code')) return;
    void handleShopWechatCallback()
      .then((result) => {
        if (!result) return;
        const session = handleShopWechatLoginResult(result);
        if (session) {
          applySession(session);
          stripOAuthParamsFromLocation();
          setSearchParams({}, { replace: true });
          routeAfterShopLogin(session, navigate);
        }
      })
      .catch((e) => setMsg(formatWechatError(e)));
  }, [applySession, navigate, params, setSearchParams, wxAuthorize]);

  const quickStoreName = savedProfile?.storeName ?? '门店管理中心';
  const quickPhone = savedProfile?.phone || phone;

  function ensureAgreed() {
    if (!agreed) {
      setMsg('请先阅读并同意用户协议');
      agreementRef.current?.scrollIntoView({ behavior: 'smooth', block: 'center' });
      return false;
    }
    return true;
  }

  async function sendCode() {
    if (!ensureAgreed()) return;
    setMsg('');
    try {
      await request('SHOP_H5', '/shop/auth/sms/send', {
        method: 'POST',
        body: JSON.stringify({ phone, scene: 'STORE_LOGIN' }),
      });
      setMsg('验证码已发送');
      setCodeCooldown(60);
      const timer = setInterval(() => {
        setCodeCooldown((c) => {
          if (c <= 1) {
            clearInterval(timer);
            return 0;
          }
          return c - 1;
        });
      }, 1000);
    } catch (e) {
      setMsg(e instanceof Error ? e.message : '发送失败');
    }
  }

  async function login() {
    if (!ensureAgreed()) return;
    setLoading(true);
    setMsg('');
    try {
      const data = await request<ShopSessionPayload>('SHOP_H5', '/shop/auth/login/sms', {
        method: 'POST',
        body: JSON.stringify({ phone, code }),
      });
      saveAuth(data);
      applySession(data);
      if (isWechatEnv() && wxAuthorize) {
        setMsg('登录成功，正在关联微信…');
        await bindShopWechatAfterSmsLogin();
        return;
      }
      routeAfterShopLogin(data, navigate);
    } catch (e) {
      setMsg(e instanceof Error ? e.message : '登录失败');
    } finally {
      setLoading(false);
    }
  }

  async function wechatLogin() {
    if (!ensureAgreed()) return;
    setMsg('');
    if (!isWechatEnv()) {
      setMsg('请在微信内打开以使用微信一键登录');
      return;
    }
    setWxLoading(true);
    try {
      const session = await loginShopWithWechat();
      if (session) {
        applySession(session);
        routeAfterShopLogin(session, navigate);
      }
    } catch (e) {
      setMsg(formatWechatError(e));
    } finally {
      setWxLoading(false);
    }
  }

  if (quick) {
    const canWechatQuick = wxAuthorize && isWechatEnv() && hasShopWxSession() && !!savedProfile;

    return (
      <div className="shop-quick-login-page">
        <header className="shop-quick-header">
          <AppImage src="/logo.png" alt="杜康好客" wrapperClassName="shop-quick-logo" fit="contain" />
          <h1 className="shop-quick-welcome">欢迎回来</h1>
          <div className="shop-quick-welcome-line" />
        </header>

        <section className="shop-quick-store-card">
          <div className="shop-quick-store-inner">
            <div className="shop-quick-store-icon">
              <span className="material-symbols-outlined shop-fill-icon">storefront</span>
            </div>
            <div>
              <h2 className="shop-quick-store-name">{quickStoreName}</h2>
              <p className="shop-quick-store-phone">{maskPhone(quickPhone)}</p>
            </div>
            <span className="shop-quick-verified">
              <span className="material-symbols-outlined shop-fill-icon" style={{ fontSize: 14 }}>verified_user</span>
              认证门店
            </span>
            <div className="shop-quick-switch">
              <Link to="/login">
                <span className="material-symbols-outlined" style={{ fontSize: 18 }}>sync</span>
                切换账号
              </Link>
            </div>
          </div>
        </section>

        <div className="shop-quick-actions">
          {msg && <p className="shop-login-msg">{msg}</p>}
          <ShopAgreementCheckbox
            agreed={agreed}
            onChange={setAgreed}
            labelRef={agreementRef}
          />
          {canWechatQuick ? (
            <button
              type="button"
              className="shop-quick-login-btn shop-quick-login-btn--wechat"
              disabled={wxLoading}
              onClick={() => void wechatLogin()}
            >
              <span className="material-symbols-outlined">chat</span>
              <span>{wxLoading ? '登录中...' : '微信一键登录'}</span>
            </button>
          ) : (
            <p className="shop-login-msg" style={{ textAlign: 'center' }}>
              {wxAuthorize && !isWechatEnv()
                ? '请在微信内打开以使用一键登录'
                : '请使用验证码登录并绑定微信后，即可 7 天内免登录'}
            </p>
          )}
          {!canWechatQuick && (
            <Link to="/login" className="shop-quick-login-btn" style={{ textAlign: 'center', textDecoration: 'none' }}>
              验证码登录
            </Link>
          )}
          <div className="shop-quick-secure">
            <span className="material-symbols-outlined" style={{ fontSize: 16 }}>lock</span>
            <span>{canWechatQuick ? '微信验证 · 7 天内免登录' : '加密环境安全登录中'}</span>
          </div>
        </div>

        <footer className="shop-quick-footer">
          <p className="shop-login-footer-brand">SECURED BY DUKANG HERITAGE</p>
          <p style={{ fontSize: 10, fontFamily: 'var(--font-label)' }}>© 2024 杜康酒业门店管理系统</p>
        </footer>
      </div>
    );
  }

  return (
    <div className="shop-login-page">
      <header className="shop-login-hero">
        <div className="shop-login-logo-wrap">
          <AppImage src="/logo.png" alt="杜康好客" wrapperClassName="app-image--fill" fit="contain" />
        </div>
        <h1 className="shop-login-brand">杜康好客</h1>
        <p className="shop-login-tagline">门店管理系统</p>
      </header>

      <main className="shop-login-main">
        <div className="shop-login-card">
          <div className="shop-login-field">
            <label htmlFor="phone">手机号码</label>
            <div className="shop-login-input-wrap">
              <span className="material-symbols-outlined">phone_iphone</span>
              <input
                id="phone"
                type="tel"
                maxLength={11}
                placeholder="请输入您的手机号"
                value={phone}
                onChange={(e) => setPhone(e.target.value)}
              />
            </div>
          </div>

          <div className="shop-login-field">
            <label htmlFor="code">验证码</label>
            <div className="shop-login-code-row">
              <div className="shop-login-input-wrap">
                <span className="material-symbols-outlined">shield</span>
                <input
                  id="code"
                  type="text"
                  maxLength={6}
                  placeholder="验证码"
                  value={code}
                  onChange={(e) => setCode(e.target.value)}
                />
              </div>
              <button
                type="button"
                className="shop-login-code-btn"
                disabled={codeCooldown > 0}
                onClick={sendCode}
              >
                {codeCooldown > 0 ? `${codeCooldown}s` : '获取验证码'}
              </button>
            </div>
          </div>

          {msg && <p className="shop-login-msg">{msg}</p>}

          <ShopAgreementCheckbox
            agreed={agreed}
            onChange={setAgreed}
            labelRef={agreementRef}
          />

          <button
            type="button"
            className="shop-login-submit"
            disabled={loading}
            onClick={() => void login()}
          >
            <span>{loading ? '登录中...' : '登录'}</span>
            {!loading && <span className="material-symbols-outlined">arrow_forward</span>}
          </button>

          {wxAuthorize && (
            <>
              <div className="shop-login-divider">
                <span className="shop-login-divider-line" />
                <span className="shop-login-divider-text">或者</span>
                <span className="shop-login-divider-line" />
              </div>

              <button
                type="button"
                className="shop-login-wechat"
                disabled={wxLoading}
                onClick={() => void wechatLogin()}
              >
                <span className="material-symbols-outlined">chat</span>
                <span>{wxLoading ? '登录中...' : '微信一键登录'}</span>
              </button>
            </>
          )}
        </div>
      </main>

      <footer className="shop-login-footer">
        <p className="shop-login-footer-brand">Secured by DUKANG HERITAGE</p>
        <span className="material-symbols-outlined shop-fill-icon" style={{ opacity: 0.3, fontSize: 20, color: 'var(--color-outline)' }}>
          security
        </span>
        {hasShopWxSession() && savedProfile && (
          <p style={{ marginTop: 16, textAlign: 'center' }}>
            <Link to="/login?quick=1" className="text-primary body-md">微信快捷登录</Link>
          </p>
        )}
      </footer>
    </div>
  );
}