<?php

/**
 * @file
 * Checks to see if your installed modules are available for a selected major
 * release of Drupal.
 */

/**
 * Default version of core we want to query for.
 */
define('UPGRADE_STATUS_CORE_VERSION', '10.2.x');

/**
 * Project has a new release available, but it is not a security release.
 */
define('UPGRADE_STATUS_DEVELOPMENT', 1000);

/**
 * Project is available.
 */
define('UPGRADE_STATUS_STABLE', 5);

/**
 * Project has been moved into core.
 */
define('UPGRADE_STATUS_CORE', 5000);

/**
 * Project has become obsolete by an alternative.
 */
define('UPGRADE_STATUS_OBSOLETE', 3000);

/**
 * Project does not exist for this version (yet).
 */
define('UPGRADE_STATUS_UNAVAILABLE', 6000);

/**
 * Implementation of hook_menu().
 */
function upgrade_status_menu() {
  $items['admin/reports/updates/upgrade'] = array(
    'title' => 'Upgrade Status',
    'page callback' => 'upgrade_status_status',
    'access arguments' => array('administer site configuration'),
    'type' => MENU_LOCAL_TASK,
    'weight' => 10,
    'file' => 'upgrade_status.report.inc'
  );
  return $items;
}

/**
 * Implementation of hook_theme().
 */
function upgrade_status_theme() {
  return array(
    'upgrade_status_report' => array(
      'variables' => array('data' => NULL),
      'file' => 'upgrade_status.report.inc',
    ),
    'upgrade_status_status_label' => array(
      'variables' => array('status' => NULL, 'project' => NULL),
    ),
  );
}

/**
 * Tries to get update information from cache and refreshes it when necessary.
 *
 * In addition to checking the cache lifetime, this function also ensures that
 * there are no .info files for enabled modules or themes that have a newer
 * modification timestamp than the last time we checked for available update
 * data. If any .info file was modified, it almost certainly means a new version
 * of something was installed. Without fresh available update data, the logic in
 * update_calculate_project_data() will be wrong and produce confusing, bogus
 * results.
 *
 * @param $refresh
 *   (optional) Boolean to indicate if this method should refresh the cache
 *   automatically if there's no data. Defaults to FALSE.
 *
 * @return
 *   Array of data about available releases, keyed by project shortname.
 *
 * @see update_get_projects()
 */
function upgrade_status_get_available($refresh = FALSE) {
  module_load_include('inc', 'upgrade_status', 'upgrade_status.compare');
  $needs_refresh = FALSE;

  // Grab whatever data we currently have cached in the DB.
  $available = _upgrade_status_get_cached_available_releases();
  $num_avail = count($available);

  $projects = update_get_projects();
  foreach ($projects as $key => $project) {
    // If there's no data at all, we clearly need to fetch some.
    if (empty($available[$key])) {
      upgrade_status_create_fetch_task($project);
      $needs_refresh = TRUE;
      continue;
    }

    // See if the .info file is newer than the last time we checked for data,
    // and if so, mark this project's data as needing to be re-fetched. Any
    // time an admin upgrades their local installation, the .info file will
    // be changed, so this is the only way we can be sure we're not showing
    // bogus information right after they upgrade.
    if ($project['info']['_info_file_ctime'] > $available[$key]['last_fetch']) {
      $available[$key]['fetch_status'] = UPDATE_FETCH_PENDING;
    }

    // If we have project data but no release data, we need to fetch. This
    // can be triggered when we fail to contact a release history server.
    if (empty($available[$key]['releases'])) {
      $available[$key]['fetch_status'] = UPDATE_FETCH_PENDING;
    }

    // If we think this project needs to fetch, actually create the task now
    // and remember that we think we're missing some data.
    if (!empty($available[$key]['fetch_status']) && $available[$key]['fetch_status'] == UPDATE_FETCH_PENDING) {
      upgrade_status_create_fetch_task($project);
      $needs_refresh = TRUE;
    }
  }

  if ($needs_refresh && $refresh) {
    // Attempt to drain the queue of fetch tasks.
    upgrade_status_fetch_data();
    // After processing the queue, we've (hopefully) got better data, so pull
    // the latest from the cache again and use that directly.
    $available = _upgrade_status_get_cached_available_releases();
  }

  return $available;
}

/**
 * Creates a new fetch task after loading the necessary include file.
 *
 * @param $project
 *   Associative array of information about a project. See update_get_projects()
 *   for the keys used.
 *
 * @see _upgrade_status_create_fetch_task()
 */
function upgrade_status_create_fetch_task($project) {
  module_load_include('inc', 'upgrade_status', 'upgrade_status.fetch');
  return _upgrade_status_create_fetch_task($project);
}

/**
 * Attempts to fetch update data after loading the necessary include file.
 *
 * @see _upgrade_status_fetch_data()
 */
function upgrade_status_fetch_data() {
  module_load_include('inc', 'upgrade_status', 'upgrade_status.fetch');
  return _upgrade_status_fetch_data();
}

/**
 * Returns all currently cached data about available releases for all projects.
 *
 * @return
 *   Array of data about available releases, keyed by project shortname.
 */
function _upgrade_status_get_cached_available_releases() {
  $data = array();
  $cache_items = _update_get_cache_multiple('upgrade_status_available_releases');
  foreach ($cache_items as $cid => $cache) {
    $cache->data['last_fetch'] = $cache->created;
    if ($cache->expire < REQUEST_TIME) {
      $cache->data['fetch_status'] = UPDATE_FETCH_PENDING;
    }
    // The project shortname is embedded in the cache ID, even if there's no
    // data for this project in the DB at all, so use that for the indexes in
    // the array.
    $parts = explode('::', $cid, 2);
    $data[$parts[1]] = $cache->data;
  }
  return $data;
}

/**
 * Form to display Drupal core version selection.
 */
function upgrade_status_core_version_form($form, &$form_state) {
  $last = variable_get('upgrade_status_last_check', 0);

  $form['upgrade_status_core_version'] = array(
    '#type' => 'select',
    '#title' => t('Check upgrade status to version'),
    '#options' => drupal_map_assoc(array('8.9.x', '9.5.x', '10.2.x')),
    '#default_value' => variable_get('upgrade_status_core_version', UPGRADE_STATUS_CORE_VERSION),
    '#description' => $last ? t('Last checked: @time ago', array('@time' => format_interval(REQUEST_TIME - $last))) : t('Last checked: never'),
  );
  $form['submit'] = array(
    '#type' => 'submit',
    '#value' => t('Check upgrade status'),
  );
  return $form;
}

/**
 * Set the new Drupal core version in a variable; refresh project data.
 *
 * @todo Why do we do these shenanigans with the variable and not just let
 * system_settings_form_submit do its thang?
 */
function upgrade_status_core_version_form_submit($form, &$form_state) {
  variable_set('upgrade_status_core_version', $form_state['values']['upgrade_status_core_version']);
  module_load_include('inc', 'upgrade_status', 'upgrade_status.fetch');
  upgrade_status_manual_status();
}