<?php
// $Id$

/**
 * @file
 * Install, update and uninstall functions for the update module.
 */

/**
 * Implements 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) {
  $requirements = array();
  if ($phase == 'runtime') {
    if ($available = update_get_available(FALSE)) {
      module_load_include('inc', 'update', 'update.compare');
      $data = update_calculate_project_data($available);
      // First, populate the requirements for core:
      $requirements['update_core'] = _update_requirement_check($data['drupal'], 'core');
      // We don't want to check drupal a second time.
      unset($data['drupal']);
      if (!empty($data)) {
        // Now, sort our $data array based on each project's status. The
        // status constants are numbered in the right order of precedence, so
        // we just need to make sure the projects are sorted in ascending
        // order of status, and we can look at the first project we find.
        uasort($data, '_update_project_status_sort');
        $first_project = reset($data);
        $requirements['update_contrib'] = _update_requirement_check($first_project, 'contrib');
      }
    }
    else {
      $requirements['update_core']['title'] = t('Drupal core update status');
      $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;
}

/**
 * Implements hook_schema().
 */
function update_schema() {
  $schema['cache_update'] = drupal_get_schema_unprocessed('system', 'cache');
  $schema['cache_update']['description'] = 'Cache table for the Update module to store information about available releases, fetched from central server.';
  return $schema;
}

/**
 * Implements hook_install().
 */
function update_install() {
  $queue = DrupalQueue::get('update_fetch_tasks');
  $queue->createQueue();
}

/**
 * Implements hook_uninstall().
 */
function update_uninstall() {
  // Clear any variables that might be in use
  $variables = array(
    'update_check_frequency',
    'update_fetch_url',
    'update_last_check',
    'update_notification_threshold',
    'update_notify_emails',
    'update_max_fetch_attempts',
    'update_max_fetch_time',
  );
  foreach ($variables as $variable) {
    variable_del($variable);
  }
  $queue = DrupalQueue::get('update_fetch_tasks');
  $queue->deleteQueue();
}

/**
 * Private helper method to fill in the requirements array.
 *
 * This is shared for both core and contrib to generate the right elements in
 * the array for hook_requirements().
 *
 * @param $project
 *  Array of information about the project we're testing as returned by
 *  update_calculate_project_data().
 * @param $type
 *  What kind of project is this ('core' or 'contrib').
 *
 * @return
 *  An array to be included in the nested $requirements array.
 *
 * @see hook_requirements()
 * @see update_requirements()
 * @see update_calculate_project_data()
 */
function _update_requirement_check($project, $type) {
  $requirement = array();
  if ($type == 'core') {
    $requirement['title'] = t('Drupal core update status');
  }
  else {
    $requirement['title'] = t('Module and theme update status');
  }
  $status = $project['status'];
  if ($status != UPDATE_CURRENT) {
    $requirement['reason'] = $status;
    $requirement['description'] = _update_message_text($type, $status, TRUE);
    $requirement['severity'] = REQUIREMENT_ERROR;
  }
  switch ($status) {
    case UPDATE_NOT_SECURE:
      $requirement_label = t('Not secure!');
      break;
    case UPDATE_REVOKED:
      $requirement_label = t('Revoked!');
      break;
    case UPDATE_NOT_SUPPORTED:
      $requirement_label = t('Unsupported release');
      break;
    case UPDATE_NOT_CURRENT:
      $requirement_label = t('Out of date');
      $requirement['severity'] = REQUIREMENT_WARNING;
      break;
    case UPDATE_UNKNOWN:
    case UPDATE_NOT_CHECKED:
    case UPDATE_NOT_FETCHED:
      $requirement_label = isset($project['reason']) ? $project['reason'] : t('Can not determine status');
      $requirement['severity'] = REQUIREMENT_WARNING;
      break;
    default:
      $requirement_label = t('Up to date');
  }
  if ($status != UPDATE_CURRENT && $type == 'core' && isset($project['recommended'])) {
    $requirement_label .= ' ' . t('(version @version available)', array('@version' => $project['recommended']));
  }
  $requirement['value'] = l($requirement_label, update_manager_access() ? 'admin/reports/updates/update' : 'admin/reports/updates');
  return $requirement;
}

/**
 * @defgroup updates-6.x-to-7.x Filter updates from 6.x to 7.x
 * @{
 */

/**
 * Create a queue to store tasks for requests to fetch available update data.
 */
function update_update_7000() {
  module_load_include('inc', 'system', 'system.queue');
  $queue = DrupalQueue::get('update_fetch_tasks');
  $queue->createQueue();
}

/**
 * Recreates cache_update table.
 *
 * Converts fields that hold serialized variables from text to blob.
 * Removes 'headers' column.
 */
function update_update_7001() {
  $schema = system_schema_cache_7054();

  db_drop_table('cache_update');
  db_create_table('cache_update', $schema);
}

/**
 * @} End of "defgroup updates-6.x-to-7.x"
 * The next series of updates should start at 8000.
 */
