<input type="text" placeholder="username" name="username"  />
    </div>
  </div>
  <div class="login-password">
    <div class="password-title">
      <h3>password:</h3>
    </div>
    <div class="password-input">
      <input type="password" placeholder="password" name="password"  />
    </div>
  </div>
  <div class="login-password">
    <div class="password-title">
      <h3>confirm password:</h3>
    </div>
    <div class="password-input">
      <input type="password" placeholder="password" name="pwagain"  />
    </div>

public function sign()
{
 $categories = $this->categoryRepository->allCategories();
 $abort = false;
 $error = "";
 if(!empty($_POST['username']) AND !empty($_POST['password']) AND !empty($_POST['pwagain'])) {
  $username = $_POST['username'];
  $password = $_POST['password'];
  $pwagain = $_POST['pwagain'];

public function logout()
{
  $this->loginService->logout();
  $_POST = [];
  $_SESSION = [];
  header("Location: index");
}

public function login()
{
 $categories = $this->categoryRepository->allCategories();

  $error = false;
  if(!empty($_POST['name']) AND !empty($_POST['pw'])){
    $username = $_POST['name'];
    $password = $_POST['pw'];

  if ($this->loginService->attempt($username, $password)) {
    header("Location: index");
    return;
  } else {
    $error = true;
  }
 }

$user =
 $this->render("user/login", [
  'error' => $error,
  'categories' => $categories,
 ]);
}