<?php

/*
 * This file is part of the Access to Memory (AtoM) software.
 *
 * Access to Memory (AtoM) is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Affero General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * Access to Memory (AtoM) is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with Access to Memory (AtoM).  If not, see <http://www.gnu.org/licenses/>.
 */

class arRestApiPluginHttpAuthFilter extends sfFilter
{
  public function execute($filterChain)
  {
    if (!$this->isFirstCall())
    {
      $filterChain->execute();

      return;
    }

    $context = $this->getContext();

    // If the user have been already authenticated (e.g. via cookies/session),
    // we can just ignore the Authorization header and let it pass.
    if ($context->getUser()->isAuthenticated())
    {
      $filterChain->execute();

      return;
    }


    // We want to give the anonymous user a chance to access to the requested
    // resource. Obviously, we want to discard cases where the user has sent us
    // the Authorization header.
    // Unfortunately, sfWebRequest::getHttpHeader() won't work for that specific
    // header in mod_php (never makes it into $_SERVER), so we are just going to
    // check if PHP_AUTH_USER and PHP_AUTH_PW are set.
    if (!isset($_SERVER['PHP_AUTH_USER']) || !isset($_SERVER['PHP_AUTH_PW']))
    {
      $filterChain->execute();

      return;
    }

    // Authenticate
    if (!$context->getUser()->authenticate($_SERVER['PHP_AUTH_USER'], $_SERVER['PHP_AUTH_PW']))
    {
      $this->sendUnauthorizedHeader();

      throw new sfStopException();
    }

    $filterChain->execute();
  }

  protected function sendUnauthorizedHeader()
  {
    // We avoid using WWW-Authentication, otherwise the browser will prompt the
    // user for credentials even when using XHR
    // Don't: header('WWW-Authenticate: Basic realm="Secure area"');

    header('HTTP/1.0 401 Unauthorized');
  }
}
