<?php
  session_start();

  $username = "";
  $email = "";
  $errors = array();
  $_SESSION['success'] = "";

  //zur Datenbank verbinden
  $db = mysqli_connect('localhost', 'root', '', 'registration');

  //wenn der registrierknopf geklickt wurde
  if (isset($_POST['reg_user'])) {
    $username = mysql_real_escape_string($db, $_POST['username']);
    $email = mysql_real_escape_string($db, $_POST['email']);
    $password_1 = mysql_real_escape_string($db, $_POST['password_1']);
    $password_2 = mysql_real_escape_string($db, $_POST['password_2']);

    //checken ob Anmeldedaten richtig sind
    if (empty($username)) { array_push($errors, "Username is required"); }
    if (empty($email)) { array_push($errors, "Email is required"); }
    if (empty($password_1)) { array_push($errors, "Password is required"); }

    if ($password_1 != $password_2) {
      array_push($errors, "The two passwords do not match");
    }

    // register user if there are no errors in the form
    if (count($errors) == 0) {
      $password = md5($password_1);//encrypt the password before saving in the database
      $query = "INSERT INTO users (username, email, password)
            VALUES('$username', '$email', '$password')";
      mysqli_query($db, $query);

      $_SESSION['username'] = $username;
			$_SESSION['success'] = "You are now logged in";
			header('location: index.php');
    }

  }
  if (isset($_POST['login_user'])) {
    $username = mysqli_real_escape_string($db, $_POST['username']);
    $password = mysqli_real_escape_string($db, $_POST['password']);

    if (empty($username)) {
      array_push($errors, "Username is required");
    }
    if (empty($password)) {
      array_push($errors, "Password is required");
    }

    if (count($errors) == 0) {
      $password = md5($password);
      $query = "SELECT * FROM users WHERE username='$username' AND password='$password'";
      $results = mysqli_query($db, $query);

      if (mysqli_num_rows($results) == 1) {
        $_SESSION['username'] = $username;
        $_SESSION['success'] = "You are now logged in";
        header('location: index.php');
      }else {
        array_push($errors, "Wrong username/password combination");
      }
    }
  }

 ?>