add authentication

app/Controllers/EventController.php

-
 <?php
 // app/Controllers/EventController.php
 
+ob_start();
 require_once(__DIR__ . '/../Models/Event.php');
 
+if (!isset($_SESSION["user_id"])) {
+    // User is not authenticated; redirect to login page
+    header("Location: /app/Views/login/login.php");
+    ob_end_flush();
+}
+
 class EventController {
     private $eventModel;
 

app/Controllers/TicketController.php

 <?php
 // app/controllers/ticketController.php
 
+ob_start();
 // require_once 'Ticket.php';
 require_once(__DIR__ . '/../Models/Ticket.php');
 
+if (!isset($_SESSION["user_id"])) {
+    // User is not authenticated; redirect to login page
+    header("Location: /app/Views/login/login.php");
+    ob_end_flush();
+}
+
 class TicketController {
     private $ticketModel;
 

app/Controllers/UserController.php

@@ -38,6 +38,7 @@ class UserController {
     public function loginByEmail($email,$password) {
         $user = $this->userModel->getUserByEmail($email);
         if ($user !== false && password_verify($password, $user['user_hashedPass'])) {
+            session_start();
             $_SESSION["user_id"] = $user['user_ID'];
             return "success";
         } else {
@@ -48,6 +49,7 @@ class UserController {
     public function loginByUsername($username,$password) {
         $user = $this->userModel->getUserByUsername($username);
         if ($user !== false && password_verify($password, $user['user_hashedPass'])) {
+            session_start();
             $_SESSION["user_id"] = $user['user_ID'];
             return "success";
         } else {