adminfront 로그인 페이지에 auto redirect SSO 진입 추가

adminfront/src/features/auth/AuthCallbackPage.tsx

@@ -14,7 +14,14 @@ function AuthCallbackPage() {
       if (user?.access_token) {
         window.localStorage.setItem("admin_session", user.access_token);
       }
-      navigate("/", { replace: true });
+      const returnTo =
+        typeof auth.user?.state === "object" &&
+        auth.user?.state !== null &&
+        "returnTo" in auth.user.state &&
+        typeof auth.user.state.returnTo === "string"
+          ? auth.user.state.returnTo
+          : "/";
+      navigate(returnTo, { replace: true });
     } else if (auth.error) {
       console.error("Auth Error:", auth.error);
       navigate("/login", { replace: true });

adminfront/src/features/auth/LoginPage.tsx

@@ -1,5 +1,7 @@
 import { ExternalLink, LogIn, ShieldHalf } from "lucide-react";
+import { useEffect, useRef } from "react";
 import { useAuth } from "react-oidc-context";
+import { useNavigate, useSearchParams } from "react-router-dom";
 import { Button } from "../../components/ui/button";
 import {
   Card,
@@ -11,10 +13,46 @@ import {
 
 function LoginPage() {
   const auth = useAuth();
+  const navigate = useNavigate();
+  const [searchParams] = useSearchParams();
+  const autoStartedRef = useRef(false);
+  const returnTo = searchParams.get("returnTo") || "/";
+  const shouldAutoLogin = searchParams.get("auto") === "1";
+
+  useEffect(() => {
+    if (auth.isAuthenticated) {
+      navigate(returnTo, { replace: true });
+    }
+  }, [auth.isAuthenticated, navigate, returnTo]);
+
+  useEffect(() => {
+    if (!shouldAutoLogin) {
+      return;
+    }
+    if (autoStartedRef.current || auth.isLoading || auth.activeNavigator) {
+      return;
+    }
+
+    autoStartedRef.current = true;
+    void auth.signinRedirect({
+      state: {
+        returnTo,
+      },
+    });
+  }, [
+    auth,
+    auth.activeNavigator,
+    auth.isLoading,
+    returnTo,
+    shouldAutoLogin,
+  ]);
 
   const handleSSOLogin = () => {
-    // OIDC client-side authentication flow started here
-    auth.signinRedirect();
+    void auth.signinRedirect({
+      state: {
+        returnTo: "/",
+      },
+    });
   };
 
   return (