<?php
  include_once("../vendor/autoload.php");
  session_start();

  if(isset($_SESSION["loggedin"]) && $_SESSION["loggedin"] === true)
  {
      header("location: /mainpage.php");
      exit;
  }

  if (!empty($_POST))
  {

    $username = $_POST["email"];
    $password = $_POST["password"];
    $mng = new MongoDB\Driver\Manager("mongodb://localhost:27017");

    $filter = [
                '_id'=>$username,
                'password' =>$password
              ];

    $query = new MongoDB\Driver\Query($filter);
    $cursor = $mng->executeQuery('Assignment2.MyUsersCollection', $query);

    foreach($cursor as $row)
    {
        $_SESSION["userid"] = $row->_id;
        $_SESSION["loggedin"] = true;
        header("location: /mainpage.php");
    }

    echo '<script type="text/JavaScript">
            alert("Your UserID or Password is incorrect");
          </script>';
}
?>