<?php
// $Id$

/**
 * @file
 * The "Update status" module checks for available updates of Drupal core and
 * any installed contributed modules and themes. It warns site administrators
 * if newer releases are available via the system status report
 * (admin/reports/status), the module and theme pages, and optionally via email.
 */

/**
 * URL to check for updates, if a given project doesn't define its own.
 */
define('UPDATE_DEFAULT_URL', 'http://updates.drupal.org/release-history');

// These are internally used constants for this code, do not modify.

/**
 * Project is up to date.
 */
define('UPDATE_CURRENT', 1);

/**
 * Project is missing security update(s).
 */
define('UPDATE_NOT_SECURE', 2);

/**
 * Project has a new release available, but it is not a security release.
 */
define('UPDATE_NOT_CURRENT', 3);

/**
 * Project's status cannot be checked.
 */
define('UPDATE_NOT_CHECKED', 4);

/**
 * No available update data was found for project.
 */
define('UPDATE_UNKNOWN', 5);

/**
 * Implementation of hook_help().
 */
function update_help($path, $arg) {
  switch ($path) {
    case 'admin/reports/updates':
      $output = '<p>'. t('Here you can find information about available updates for your installed modules and themes. Note that each module or theme is part of a "project", which may or may not have the same name, and might include multiple modules or themes within it.') .'</p>';
      $output .= '<p>'. t('To extend the functionality or to change the look of your site, a number of contributed <a href="@modules">modules</a> and <a href="@themes">themes</a> are available.', array('@modules' => 'http://drupal.org/project/modules', '@themes' => 'http://drupal.org/project/themes')) .'</p>';
      return $output;
    case 'admin/build/themes':
    case 'admin/build/modules':
      include_once './includes/install.inc';
      $status = update_requirements('runtime');
      foreach (array('core', 'contrib') as $report_type) {
        $type = 'update_'. $report_type;
        if (isset($status[$type]['severity'])) {
          if ($status[$type]['severity'] == REQUIREMENT_ERROR) {
            drupal_set_message($status[$type]['description'], 'error');
          }
          elseif ($status[$type]['severity'] == REQUIREMENT_WARNING) {
            drupal_set_message($status[$type]['description']);
          }
        }
      }
      return '<p>'. t('See the <a href="@available_updates">available updates</a> page for information on installed modules and themes with new versions released.', array('@available_updates' => url('admin/reports/updates'))) .'</p>';

    case 'admin/reports/updates/settings':
    case 'admin/reports/status':
      // These two pages don't need additional nagging.
      break;

    case 'admin/help#update':
      $output = '<p>'. t("The Update status module periodically checks for new versions of your site's software (including contributed modules and themes), and alerts you to available updates.") .'</p>';
      $output .= '<p>'. t('The <a href="@update-report">report of available updates</a> will alert you when new releases are available for download. You may configure options for update checking frequency and notifications at the <a href="@update-settings">Update status module settings page</a>.', array('@update-report' => url('admin/logs/updates'), '@update-settings' => url('admin/logs/updates/settings'))) .'</p>';
      $output .= '<p>'. t('Please note that in order to provide this information, anonymous usage statistics are sent to drupal.org. If desired, you may disable the Update status module from the <a href="@modules">module administration page</a>.', array('@modules' => url('admin/build/modules'))) .'</p>';
      $output .= '<p>'. t('For more information please read the configuration and customization handbook <a href="@update">Update status page</a>.', array('@update' => 'http://drupal.org/handbook/modules/update')) .'</p>';
      return $output;

    default:
      // Otherwise, if we're on *any* admin page and there's a security
      // update missing, print an error message about it.
      if (arg(0) == 'admin' && strpos($path, '#') === FALSE
          && user_access('administer site configuration')) {
        include_once './includes/install.inc';
        $status = update_requirements('runtime');
        foreach (array('core', 'contrib') as $report_type) {
          $type = 'update_'. $report_type;
          if (isset($status[$type])
              && isset($status[$type]['reason'])
              && $status[$type]['reason'] === UPDATE_NOT_SECURE) {
            drupal_set_message($status[$type]['description'], 'error');
          }
        }
      }

  }
}

/**
 * Implementation of hook_menu().
 */
function update_menu() {
  $items = array();

  $items['admin/reports/updates'] = array(
    'title' => 'Available updates',
    'description' => 'Get a status report about available updates for your installed modules and themes.',
    'page callback' => 'update_status',
    'access arguments' => array('administer site configuration'),
    'file' => 'update.report.inc',
    'weight' => 10,
  );
  $items['admin/reports/updates/list'] = array(
    'title' => 'List',
    'page callback' => 'update_status',
    'access arguments' => array('administer site configuration'),
    'file' => 'update.report.inc',
    'type' => MENU_DEFAULT_LOCAL_TASK,
  );
  $items['admin/reports/updates/settings'] = array(
    'title' => 'Settings',
    'page callback' => 'drupal_get_form',
    'page arguments' => array('update_settings'),
    'access arguments' => array('administer site configuration'),
    'file' => 'update.settings.inc',
    'type' => MENU_LOCAL_TASK,
  );
  $items['admin/reports/updates/check'] = array(
    'title' => 'Manual update check',
    'page callback' => 'update_manual_status',
    'access arguments' => array('administer site configuration'),
    'file' => 'update.fetch.inc',
    'type' => MENU_CALLBACK,
  );

  return $items;
}

/**
 * Implementation of the hook_theme() registry.
 */
function update_theme() {
  return array(
    'update_settings' => array(
      'arguments' => array('form' => NULL),
    ),
    'update_report' => array(
      'arguments' => array('data' => NULL),
    ),
    'update_version' => array(
      'arguments' => array('version' => NULL, 'tag' => NULL, 'class' => NULL),
    ),
  );
}

/**
 * Implementation of hook_requirements.
 *
 * @return
 *   An array describing the status of the site regarding available updates.
 *   If there is no update data, only one record will be returned, indicating
 *   that the status of core can't be determined. If data is available, there
 *   will be two records: one for core, and another for all of contrib
 *   (assuming there are any contributed modules or themes enabled on the
 *   site). In addition to the fields expected by hook_requirements ('value',
 *   'severity', and optionally 'description'), this array will contain a
 *   'reason' attribute, which is an integer constant to indicate why the
 *   given status is being returned (UPDATE_NOT_SECURE, UPDATE_NOT_CURRENT, or
 *   UPDATE_UNKNOWN). This is used for generating the appropriate e-mail
 *   notification messages during update_cron(), and might be useful for other
 *   modules that invoke update_requirements() to find out if the site is up
 *   to date or not.
 *
 * @see _update_message_text()
 * @see _update_cron_notify()
 */
function update_requirements($phase) {
  if ($phase == 'runtime') {
    $requirements['update_core']['title'] = t('Drupal core update status');
    $notification_level = variable_get('update_notification_threshold', 'all');
    if ($available = update_get_available(FALSE)) {
      include_once './modules/update/update.compare.inc';
      $data = update_calculate_project_data($available);
      switch ($data['drupal']['status']) {
        case UPDATE_NOT_CURRENT:
          $requirements['update_core']['value'] = t('Out of date (version @version available)', array('@version' => $data['drupal']['recommended']));
          $requirements['update_core']['severity'] = $notification_level == 'all' ? REQUIREMENT_ERROR : REQUIREMENT_WARNING;
          $requirements['update_core']['reason'] = UPDATE_NOT_CURRENT;
          $requirements['update_core']['description'] = _update_message_text('core', UPDATE_NOT_CURRENT, TRUE);
          break;

        case UPDATE_NOT_SECURE:
          $requirements['update_core']['value'] = t('Not secure! (version @version available)', array('@version' => $data['drupal']['recommended']));
          $requirements['update_core']['severity'] = REQUIREMENT_ERROR;
          $requirements['update_core']['reason'] = UPDATE_NOT_SECURE;
          $requirements['update_core']['description'] = _update_message_text('core', UDPDATE_NOT_SECURE, TRUE);
          break;

        default:
          $requirements['update_core']['value'] = t('Up to date');
          break;
      }
      // We don't want to check drupal a second time.
      unset($data['drupal']);
      $not_current = FALSE;
      if (!empty($data)) {
        $requirements['update_contrib']['title'] = t('Module and theme update status');
        // Default to being current until we see otherwise.
        $requirements['update_contrib']['value'] = t('Up to date');
        foreach (array_keys($data) as $project) {
          if (isset($available[$project])) {
            if ($data[$project]['status'] == UPDATE_NOT_SECURE) {
              $requirements['update_contrib']['value'] = t('Not secure!');
              $requirements['update_contrib']['severity'] = REQUIREMENT_ERROR;
              $requirements['update_contrib']['reason'] = UPDATE_NOT_SECURE;
              $requirements['update_contrib']['description'] = _update_message_text('contrib', UPDATE_NOT_SECURE, TRUE);
              break;
            }
            elseif ($data[$project]['status'] == UPDATE_NOT_CURRENT) {
              $not_current = TRUE;
            }
          }
        }
        if (!isset($requirements['update_contrib']['severity']) && $not_current) {
          $requirements['update_contrib']['severity'] = $notification_level == 'all' ? REQUIREMENT_ERROR : REQUIREMENT_WARNING;
          $requirements['update_contrib']['value'] = t('Out of date');
          $requirements['update_contrib']['reason'] = UPDATE_NOT_CURRENT;
          $requirements['update_contrib']['description'] = _update_message_text('contrib', UPDATE_NOT_CURRENT, TRUE);
        }
      }
    }
    else {
      $requirements['update_core']['value'] = t('No update data available');
      $requirements['update_core']['severity'] = REQUIREMENT_WARNING;
      $requirements['update_core']['reason'] = UPDATE_UNKNOWN;
      $requirements['update_core']['description'] = _update_no_data();
    }
    return $requirements;
  }
}

/**
 * Implementation of hook_cron().
 */
function update_cron() {
  $frequency = variable_get('update_check_frequency', 1);
  $interval = 60 * 60 * 24 * $frequency;
  if (time() - variable_get('update_last_check', 0) > $interval) {
    update_refresh();
    _update_cron_notify();
  }
}

/**
 * Implementation of hook_form_alter().
 *
 * Adds a submit handler to the system modules and themes forms, so that if a
 * site admin saves either form, we invalidate the cache of available updates.
 *
 * @see update_invalidate_cache()
 */
function update_form_alter(&$form, $form_state, $form_id) {
  if ($form_id == 'system_modules' || $form_id == 'system_themes' ) {
    $form['#submit'][] = 'update_invalidate_cache';
  }
}

/**
 * Prints a warning message when there is no data about available updates.
 */
function _update_no_data() {
  $destination = drupal_get_destination();
  return t('No information is available about potential new releases for currently installed modules and themes. To check for updates, you may need to <a href="@run_cron">run cron</a> or you can <a href="@check_manually">check manually</a>. Please note that checking for available updates can take a long time, so please be patient.', array(
    '@run_cron' => url('admin/reports/status/run-cron', array('query' => $destination)),
    '@check_manually' => url('admin/reports/updates/check', array('query' => $destination)),
  ));
}

/**
 * Internal helper to try to get the update information from the cache
 * if possible, and to refresh the cache when necessary.
 *
 * @param $refresh
 *   Boolean to indicate if this method should refresh the cache automatically
 *   if there's no data.
 */
function update_get_available($refresh = FALSE) {
  $available = array();
  if (($cache = cache_get('update_info', 'cache_update'))
       && $cache->expire > time()) {
    $available = $cache->data;
  }
  elseif ($refresh) {
    $available = update_refresh();
  }
  return $available;
}

/**
 * Invalidates any cached data relating to update status.
 */
function update_invalidate_cache() {
  cache_clear_all('update_info', 'cache_update');
}

/**
 * Wrapper to load the include file and then refresh the release data.
 */
function update_refresh() {
  include_once './modules/update/update.fetch.inc';
  return _update_refresh();
}

/**
 * Implementation of hook_mail().
 *
 * Constructs the email notification message when the site is out of date.
 *
 * @param $key
 *   Unique key to indicate what message to build, always 'status_notify'.
 * @param $message
 *   Reference to the message array being built.
 * @param $params
 *   Array of parameters to indicate what kind of text to include in the
 *   message body. This is a keyed array of message type ('core' or 'contrib')
 *   as the keys, and the status reason constant (UPDATE_NOT_SECURE, etc) for
 *   the values.
 *
 * @see drupal_mail();
 * @see _update_cron_notify();
 * @see _update_message_text();
 */
function update_mail($key, &$message, $params) {
  $language = $message['language'];
  $langcode = $language->language;
  $message['subject'] .= t('New release(s) available for !site_name', array('!site_name' => variable_get('site_name', 'Drupal')), $langcode);
  foreach ($params as $msg_type => $msg_reason) {
    $message['body'][] = _update_message_text($msg_type, $msg_reason, FALSE, $language);
  }
  $message['body'][] = t('See the available updates page for more information:', array(), $langcode) ."\n". url('admin/reports/updates', array('absolute' => TRUE, 'language' => $language));
}

/**
 * Helper function to return the appropriate message text when the site is out
 * of date or missing a security update.
 *
 * These error messages are shared by both update_requirements() for the
 * site-wide status report at admin/reports/status and in the body of the
 * notification emails generated by update_cron().
 *
 * @param $msg_type
 *   String to indicate what kind of message to generate. Can be either
 *   'core' or 'contrib'.
 * @param $msg_reason
 *   Integer constant specifying why message is generated. Can be either
 *   UPDATE_NOT_CURRENT or UPDATE_NOT_SECURE.
 * @param $report_link
 *   Boolean that controls if a link to the updates report should be added.
 * @param $language
 *   An optional language object to use.
 * @return
 *   The properly translated error message for the given key.
 */
function _update_message_text($msg_type, $msg_reason, $report_link = FALSE, $language = NULL) {
  $langcode = isset($language) ? $language->language : NULL;
  $text = '';
  switch ($msg_reason) {
    case UPDATE_NOT_CURRENT:
      if ($msg_type == 'core') {
        $text = t('There are updates available for your version of Drupal. To ensure the proper functioning of your site, you should update as soon as possible.', array(), $langcode);
      }
      else {
        $text = t('There are updates available for one or more of your modules or themes. To ensure the proper functioning of your site, you should update as soon as possible.', array(), $langcode);
      }
      break;

    case UPDATE_NOT_SECURE:
      if ($msg_type == 'core') {
        $text = t('There is a security update available for your version of Drupal. To ensure the security of your server, you should update immediately!', array(), $langcode);
      }
      else {
        $text = t('There are security updates available for one or more of your modules or themes. To ensure the security of your server, you should update immediately!', array(), $langcode);
      }
      break;
  }

  if ($report_link) {
    $text .= ' '. t('See the <a href="@available_updates">available updates</a> page for more information.', array('@available_updates' => url('admin/reports/updates', array('language' => $language))), $langcode);
  }

  return $text;
}