login_class.php
<?php
class LoginClass
{
    public function loginUser($params)
    {
        $loginParams = [
            'username' => $params['username'],
            'password' => $params['password'],
            'grant_type' => 'password',
            'client_id' => 'test',
            'client_secret' => 'test'
        ];

        $curl = curl_init();
        curl_setopt($curl, CURLOPT_URL, API_V2 . '/oauth/access_token');
        curl_setopt($curl, CURLOPT_POSTFIELDS, http_build_query($loginParams));
        curl_setopt($curl, CURLOPT_RETURNTRANSFER, 1);

        $result = json_decode(curl_exec($curl), true);
        curl_close($curl);

        if ($result['message'] === 'success')
        {
            $curlUser = curl_init();
            curl_setopt($curlUser, CURLOPT_URL, API_V2 . "/me?access_token=" . $result['data']['access_token']);
            curl_setopt($curlUser, CURLOPT_RETURNTRANSFER, 1);

            $user = json_decode(curl_exec($curlUser), true);
            curl_close($curlUser);

            if ($user['status'] == 200) {

                // TEMPORARY FOR NOW
                $_SESSION['access_token'] = $results['access_token'];
                $_SESSION['expires_in'] = $results['expires_in'];
                $_SESSION['beone_user_name'] = $results['username'];
                $_SESSION['beone_user_type'] = $results['user_type'];
                $_SESSION['beone_has_store'] = $results['has_store'];
                $_SESSION['beone_email'] = $results['email'];
                $_SESSION['beone_last_name'] = $results['last_name'];
                $_SESSION['beone_first_name'] = $results['first_name'];
                $_SESSION['beone_user_type_id'] = $results['user_type_id'];
                $_SESSION['beone_payment_type'] = $results['payment_type'];
                $_SESSION['beone_user_logo'] = $results['store_logo'];
                $_SESSION['beone_user_image'] = $results['user_image'];
                $_SESSION['beone_theme_folder'] = $results['theme_folder'];
                $_SESSION['beone_user_id'] = $_SESSION['beone_new_user_id'] = $results['id'];

                $url = '/userdashboard/index.php';
                if ($results['user_type'] == 3 && $results['has_store'] == 0){
                    $url = '/campaign/not_available.php';
                }

                if (isset($params['redirect_url'])) {
                    $url = $params['redirect_url'];
                }
                header("Location: " . $url);
                die();
            }
        }

        $err = 'Invalid Username or Password';
        header("Location: /login.php?error_msg=" . $err);
        die();
    }

};