feat: authenticate user token

.env.dev

@@ -0,0 +1 @@
+SECRET_KEY_DEV=MIGRATION_API_V2_DEV;

.env.prod

@@ -0,0 +1 @@
+SECRET_KEY_PROD=MIGRATION_API_V2_PROD;

src/middlewares/auth.middleware.ts

@@ -1,16 +1,32 @@
 // middleware/authentication.middleware.ts
 import { Request, Response, NextFunction } from "express";
+import jwt from "jsonwebtoken";
 
 export const authenticateUser = (
   req: Request,
   res: Response,
   next: NextFunction
-): void => {
+) => {
   // Simulate authentication logic (e.g., check for a token)
-  const isAuthenticated = /* Your authentication logic here */ true;
-  if (isAuthenticated) {
-    next(); // User is authenticated, proceed to the next middleware or route handler
+  const token = req.headers.authorization?.split(" ")[1];
+  const secretKey =
+    process.env.NODE_ENV === "dev" ?
+      process.env.SECRET_KEY_DEV!
+      : process.env.SECRET_KEY_PROD!;
+  if (token) {
+    jwt.verify(token, secretKey, (err, decoded) => {
+      if (err) {
+        return res
+          .status(401)
+          .json({ message: "Unauthorized - Invalid token" });
+      }
+
+      // Attach the decoded token to the request object for later use
+      (req as any).decodedToken = decoded;
+
+      next();
+    });
   } else {
-    res.status(401).json({ message: "Authentication failed" });
+    return res.status(401).json({ message: "Unauthorized - Token missing" });
   }
 };