-->> index.ts ( my backend )

import express from "express";
import dotenv from "dotenv";
import cors from "cors";
import connectDB from "./config/db";
import authRoutes from "./routes/authRoutes";
import userRoutes from "./routes/UserRoutes";
import twoFaRoutes from "./routes/TwoFARoutes";
import enhanceTextRoutes from "./routes/enhanceTextRoutes";
import checklistRoutes from "./routes/checklistRoutes";
import faqRoutes from "./routes/faqRoutes";
import visitorSecurityRoutes from "./routes/visitor-routes/visitorSecurityRoutes";
import aiChatRoutes from "./routes/AI-routes/aiChatRoutes";
import incubatorRoutes from "./routes/incubator-routes/incubatorRoutes";
import resourceRoutes from "./routes/resource-routes/resourceRoutes";
import path from "path";
import templateRoutes from "./routes/template-routes/templateRoutes";
import adminRoutes from "./routes/admin-routes/adminRoutes";
import cookieParser from "cookie-parser";
import googleAuthRoutes from "./routes/google-auth/googleAuthRoutes";
import influencerRoutes from "./routes/influencer-routes/influencerRoutes";
import StartupInfluencerRoutes from "./routes/influencer-routes/StartupInfluencerRoutes";
import AngelRoutes from "./routes/angel-routes/AngelRoutes";
import preSeedRoutes from "./routes/preSeed-routes/preSeedRoutes";
import seedRoutes from "./routes/Seed-Routes/seedRoutes";

dotenv.config();

const FRONTEND_URL = "https://founders-portal-test-server-client.onrender.com";
const BACKEND_URL = "https://founders-portal-test-server-apii.onrender.com";

const app = express();
const PORT = process.env.PORT || 5000;

app.use(cookieParser());

// Middleware
app.use(
  cors({
    origin: "https://founders-portal-test-server-client.onrender.com",
    credentials: true,
    methods: ["GET", "POST", "PUT", "DELETE", "OPTIONS", "PATCH"],
    allowedHeaders: ["Content-Type", "Authorization", "Cookie"],
    exposedHeaders: ["set-cookie"],
  })
);

app.use(express.json());

app.get("/", (req, res) => {
  res.send("API is running...");
});

// Connect to Database
connectDB();

// Routes
app.use("/api/auth", googleAuthRoutes);
app.use("/api/admin", adminRoutes);

app.use("/api", authRoutes);
app.use("/api/user", userRoutes);
app.use("/api/twofa", twoFaRoutes);
app.use("/api/check", checklistRoutes);
app.use("/api/faq", faqRoutes);
app.use("/api", visitorSecurityRoutes);

app.use("/api/ai", enhanceTextRoutes);
app.use("/api/ai-chat", aiChatRoutes);

app.use("/api", incubatorRoutes);
app.use("/api", AngelRoutes);
app.use("/api", preSeedRoutes);
app.use("/api", seedRoutes);

app.use("/api", templateRoutes);

app.use("/api/resources", resourceRoutes);
app.use("/api/influencers", influencerRoutes);
app.use("/api/startup-influencers", StartupInfluencerRoutes);

app.use("/resuploads", (req, res, next) => {
  // Check if it's a download request
  if (req.query.download === "true") {
    // Set headers for download
    res.setHeader("Content-Disposition", "attachment");
  }
  next();
});

app.use("/resuploads", express.static(path.join(__dirname, "Resuploads")));

if (process.env.NODE_ENV === "development") {
  app.get("/api/debug/routes", (req, res) => {
    const routes = app._router.stack
      .filter((r: any) => r.route)
      .map((r: any) => ({
        path: r.route.path,
        methods: Object.keys(r.route.methods),
      }));
    res.json(routes);
  });
}

app.listen(PORT, () => console.log(`Server running on port ${PORT}`));

export default app;

-->> frontend ( AdminLogin.tsx ) this is where the backend is connected to

import React, { useState } from "react";
import { useNavigate } from "react-router-dom";
import { Card, message } from "antd";
import { GoogleLogin, GoogleOAuthProvider } from "@react-oauth/google";

const GOOGLE_CLIENT_ID = import.meta.env.VITE_ADMIN_PRODUCTION_GOOGLE_CLIENT_ID;
const BACKEND_URL =
  import.meta.env.VITE_BACKEND_URL ||
  "https://founders-portal-test-server-apii.onrender.com";

const AdminLogin: React.FC = () => {
  const navigate = useNavigate();
  const [loading, setLoading] = useState(false);

  const handleGoogleSuccess = async (credentialResponse: any) => {
    setLoading(true);
    try {
      const response = await fetch(`${BACKEND_URL}/api/auth/google-login`, {
        // Update with your actual backend URL
        method: "POST",
        headers: {
          "Content-Type": "application/json",
        },
        body: JSON.stringify({
          credential: credentialResponse.credential,
        }),
        credentials: "include",
        mode: "cors",
      });

      if (!response.ok) {
        throw new Error("Authentication failed");
      }

      const data = await response.json();
      if (data.isAdmin) {
        message.success("Login successful!");
        navigate("/adminPortal/dashboard");
      } else {
        message.error("You do not have admin access");
      }
    } catch (error) {
      console.error("Login error:", error);
      message.error("Login failed. Please try again.");
    } finally {
      setLoading(false);
    }
  };

  return (
    <GoogleOAuthProvider clientId={GOOGLE_CLIENT_ID}>
      <div
        style={{
          minHeight: "100vh",
          display: "flex",
          alignItems: "center",
          justifyContent: "center",
          background: "#f0f2f5",
        }}
      >
        <Card style={{ width: 400 }}>
          <h1 style={{ textAlign: "center", marginBottom: 24 }}>Admin Login</h1>
          <div style={{ display: "flex", justifyContent: "center" }}>
            <GoogleLogin
              onSuccess={handleGoogleSuccess}
              onError={() => {
                console.error("Login Failed");
                message.error("Login Failed");
              }}
              useOneTap
              theme="outline"
              size="large"
              text="continue_with"
            />
          </div>
        </Card>
      </div>
    </GoogleOAuthProvider>
  );
};

export default AdminLogin;

-->> GoogleAuthRoutes.ts ( route file, backend )

import express, { RequestHandler } from "express";
import { googleLogin } from "../../controllers/googleauthController";
import { authenticateAdmin } from "../../middleware/adminAuth";

const router = express.Router();
const FRONTEND_URL = "https://founders-portal-test-server-client.onrender.com";

// Get current user info
const getCurrentUser: RequestHandler = (req, res) => {
  res.header("Access-Control-Allow-Origin", FRONTEND_URL);
  res.header("Access-Control-Allow-Credentials", "true");
  res.json({
    id: req.adminuser?._id,
    adminemail: req.adminuser?.adminemail,
    adminname: req.adminuser?.adminname,
    adminrole: req.adminuser?.adminrole,
    profilePic: req.adminuser?.profilePic,
  });
};

// Logout handler
const logout: RequestHandler = (req, res) => {
  res.header("Access-Control-Allow-Origin", FRONTEND_URL);
  res.header("Access-Control-Allow-Credentials", "true");
  res.clearCookie("adminToken", {
    httpOnly: true,
    secure: true,
    sameSite: "none",
  });
  res.json({ message: "Logged out successfully" });
};

// Wrap googleLogin to ensure proper headers
const wrappedGoogleLogin: RequestHandler = async (req, res, next) => {
  try {
    const origin = req.headers.origin;
    if (origin === FRONTEND_URL) {
      res.header("Access-Control-Allow-Origin", FRONTEND_URL);
      res.header("Access-Control-Allow-Credentials", "true");
    }
    await googleLogin(req, res, next);
  } catch (error) {
    next(error);
  }
};

// Route definitions
router.post("/google-login", wrappedGoogleLogin);
router.get("/current-user", authenticateAdmin, getCurrentUser);
router.post("/logout", logout);

export default router;