feat: 최초가입자, 기존가입자 분기처리

src/features/auth/api/oauth.ts

@@ -2,6 +2,7 @@ import { ACCESS_TOKEN_LOCAL_STORAGE_KEY } from '../constants';
 import LocalStorage from '@/shared/utils/localStorage';
 import instance from '@/shared/api/axios/instance';
 import { API_BASE_URL } from '@/shared/api/constants';
+import { AxiosError } from 'axios';
 
 export const getAccessToken = () => LocalStorage.getItem(ACCESS_TOKEN_LOCAL_STORAGE_KEY);
 
@@ -35,6 +36,35 @@ export const getLoginToken = async (code: string) => {
   }
 };
 
+export const getNewLoginToken = async (code: string) => {
+  try {
+    const response = await instance.get(`${API_BASE_URL}/api/v1/oauth/login/new/kakao?code=${code}`);
+    const jwt = response.headers?.['authorization'] as string;
+
+    saveAccessToken(jwt);
+  } catch (error) {
+    alert('로그인 실패:');
+    console.error(error);
+  }
+};
+
+export const handleLogin = async (code: string) => {
+  try {
+    await getLoginToken(code);
+  } catch (error) {
+    if (error instanceof AxiosError) {
+      if (error.status === 400 && error.code === 'ERR_4000') {
+        // 최초 로그인 사용자인 경우
+        await getNewLoginToken(code);
+      } else {
+        alert('로그인 실패:');
+        console.error(error);
+        throw error;
+      }
+    }
+  }
+};
+
 export const saveAccessToken = (response: string) => {
   if (!response) {
     removeAccessToken();

src/features/auth/components/KakaoCallback.tsx

@@ -3,7 +3,7 @@
 import { useState, useEffect } from 'react';
 import { useRouter, useSearchParams } from 'next/navigation';
 import { useToast } from '@/shared/components/shadcn/ui/use-toast';
-import { getLoginToken } from '@/features/auth/api/oauth';
+import { handleLogin } from '@/features/auth/api/oauth';
 import { Loading } from '@/shared/components/Loading';
 
 export default function KakaoCallback() {
@@ -21,7 +21,7 @@ export default function KakaoCallback() {
 
   useEffect(() => {
     if (authCode) {
-      getLoginToken(authCode)
+      handleLogin(authCode)
         .then(() => {
           toast({
             title: '로그인 완료!',

src/features/auth/components/signup/index.tsx

@@ -6,11 +6,14 @@ import { Input } from '@/shared/components/shadcn/ui/input';
 import { Label } from '@/shared/components/shadcn/ui/label';
 import { ChangeEvent, FormEvent, KeyboardEvent, useRef, useState } from 'react';
 import { getSignupStatus } from '../../api/getSignupStatus';
+import { API_BASE_URL } from '@/shared/api/constants';
+import { useRouter } from 'next/navigation';
 
 export default function Signup() {
   const [phoneNumber, setPhoneNumber] = useState<string[]>(['010', '', '']);
   const [isValid, setIsValid] = useState<boolean>(false);
   const [error, setError] = useState<string>('');
+  const router = useRouter();
 
   const inputRefs = [useRef<HTMLInputElement>(null), useRef<HTMLInputElement>(null)];
 
@@ -52,8 +55,13 @@ export default function Signup() {
       const response = await getSignupStatus(fullNumber);
       const 회원가입된유저인가 = response.data.isDuplicatedPhoneNumber;
 
-      console.log(회원가입된유저인가);
-      // 여기에 서버로 데이터를 보내는 로직을 추가할 수 있습니다.
+      if (회원가입된유저인가) {
+        alert('이미 가입된 회원입니다. 카카오 로그인을 통해 로그인해주세요.');
+        router.push('/login');
+      } else {
+        alert('최초 가입자입니다. 카카오 로그인으로 이동합니다.');
+        window.location.href = `${API_BASE_URL}/api/v1/oauth/kakao`;
+      }
     } else {
       setError('유효한 전화번호를 입력해주세요.');
     }

src/shared/api/axios/instance.ts

@@ -29,7 +29,6 @@ instance.interceptors.response.use(
   },
   async function (error) {
     const {
-      config,
       response: { status },
     } = error;