o2o-castad-frontend/src/pages/Login/LoginSection.tsx

import React, { useState, useEffect } from 'react';
import { useTranslation } from 'react-i18next';
import { getKakaoLoginUrl, kakaoCallback, trackCompleteRegistration } from '../../utils/api';

interface LoginSectionProps {
  onBack: () => void;
  onLogin: () => void;
}

const LoginSection: React.FC<LoginSectionProps> = ({ onBack, onLogin }) => {
  const { t } = useTranslation();
  const [isLoading, setIsLoading] = useState(false);
  const [error, setError] = useState<string | null>(null);

  // 카카오 콜백 처리 (URL에서 code 파라미터 확인)
  useEffect(() => {
    const urlParams = new URLSearchParams(window.location.search);
    const code = urlParams.get('code');

    if (code) {
      handleKakaoCallback(code);
    }
  }, []);

  const handleKakaoCallback = async (code: string) => {
    setIsLoading(true);
    setError(null);

    try {
      const response = await kakaoCallback(code);

      // 신규 가입이면 Meta CompleteRegistration 전환 이벤트 발화
      // (서버가 계정당 최초 1회 판정 — App.tsx 경로와 중복 호출돼도 무해)
      if (response.is_new_user) {
        await trackCompleteRegistration();
      }

      // URL에서 code 파라미터 제거
      const url = new URL(window.location.href);
      url.searchParams.delete('code');
      window.history.replaceState({}, document.title, url.pathname);

      // 로그인 성공
      onLogin();
    } catch (err) {
      console.error('Kakao callback failed:', err);
      setError(t('login.kakaoLoginFailed'));

      // URL에서 code 파라미터 제거
      const url = new URL(window.location.href);
      url.searchParams.delete('code');
      window.history.replaceState({}, document.title, url.pathname);
    } finally {
      setIsLoading(false);
    }
  };

  const handleKakaoLogin = async () => {
    setIsLoading(true);
    setError(null);

    try {
      const response = await getKakaoLoginUrl();

      // 카카오 로그인 페이지로 리다이렉트
      window.location.href = response.auth_url;
    } catch (err) {
      console.error('Failed to get Kakao login URL:', err);
      setError(t('login.loginUrlFailed'));
      setIsLoading(false);
    }
  };

  return (
    <div className="login-container">
      {/* Back Button */}
      <button onClick={onBack} className="login-back-btn" disabled={isLoading}>
        <img src="/assets/images/icon-back.svg" alt="Back" />
        <span>{t('login.back')}</span>
      </button>

      <div className="login-content">
        {/* Logo */}
        <div className="login-logo">
          <img src="/assets/images/ADO2_with Slogan_white.svg" alt="ADO2" />
        </div>

        {/* Error Message */}
        {error && (
          <div className="login-error">
            {error}
          </div>
        )}

        {/* Kakao Login Button */}
        <button
          onClick={handleKakaoLogin}
          className="btn-kakao"
          disabled={isLoading}
        >
          {isLoading ? t('login.loggingIn') : t('login.kakaoStart')}
        </button>
      </div>
    </div>
  );
};

export default LoginSection;