index.php

<?php

require_once 'core/init.php';

$user = new User();

if ($user->isLoggedIn()) {
    $username = escape($user->data()->username);
?>
<?php include 'resources.php'; ?>

<?php if (Session::exists('success')) : ?>
  <div class="alert alert-success">
    <?php echo Session::flash('success'); ?>
  </div>
<?php endif; ?>

<?php if (Session::exists('error')) : ?>
  <div class="alert alert-danger">
    <?php echo Session::flash('error'); ?>
  </div>
<?php endif; ?>

<section class="ftco-section">
      <div class="container">
        <div class="row justify-content-center">
          <div class="col-md-6 text-center mb-4">
            <h2 class="heading-section">Welcome, <?php echo escape($user->data()->username); ?>!</h2>
          </div>
        </div>
        <div class="row justify-content-center mb-4">
          <nav class="navbar navbar-expand-lg bg-primary rounded-xlg px-2">
            <ul class="navbar-nav mr-auto font-weight-semibold">
                <li class="nav-item px-2">
                    <a class="nav-link" href="index.php?user=<?php echo escape($user->data()->username); ?>">Profile</a>
                </li>
                <li class="nav-item px-2">
                    <a class="nav-link" href="index.php?update">Edit Profile</a>
                </li>
                <li class="nav-item px-2">
                    <a class="nav-link" href="index.php?changepassword">Change Password</a>
                </li>
                <li class="nav-item px-2">
                    <a class="nav-link" href="logout.php">Logout</a>
                </li>
            </ul>
         </nav>
        </div>
        <div class="row justify-content-center">
          <div class="col-md-6">
          <?php
                if (isset($_GET['user'])) {
                    require_once 'profile.php';
                } elseif (isset($_GET['update'])) {
                    require_once 'update.php';
                } elseif (isset($_GET['changepassword'])) {
                    require_once 'changepassword.php';
                } else {
                    if (!isset($_GET['user']) || $_GET['user'] !== $username) {
                        Redirect::to("index.php?user=" . $username);
                    }
                }
            ?>
          </div>
        </div>
      </div>
    </section>
<?php
} else {
    redirect::to('login.php');
}