<?php

/**
 * Implements hook_views_api().
 */
function search_api_multi_views_api() {
  if (module_exists('search_api_views')) {
    return array(
      'api' => '3.0-alpha1',
      'path' => drupal_get_path('module', 'search_api_multi') . '/views',
    );
  }
}

/**
 * Implements hook_search_api_server_enabled().
 */
function search_api_multi_search_api_server_enabled(array $servers) {
  if (!module_exists('search_api_views')) {
    return;
  }
  foreach ($servers as $server) {
    if ($server->supportsFeature('search_api_multi')) {
      // Make the new server(s) available for views.
      views_invalidate_cache();
      break;
    }
  }
}

/**
 * Implements hook_search_api_server_update().
 */
function search_api_multi_search_api_server_update(SearchApiServer $server) {
  if (module_exists('search_api_views') && $server->supportsFeature('search_api_multi') && !$server->enabled && $server->original->enabled) {
    _search_api_multi_server_unavailable($server);
  }
}

/**
 * Implements hook_search_api_server_delete().
 */
function search_api_multi_search_api_server_delete(SearchApiServer $server) {
  if (module_exists('search_api_views') && $server->supportsFeature('search_api_multi')) {
    _search_api_multi_server_unavailable($server);
  }
}

/**
 * Function for reacting to a disabled or deleted search server.
 */
function _search_api_multi_server_unavailable(SearchApiServer $server) {
  $names = array();
  $table = 'search_api_server_' . $server->machine_name;
  foreach (views_get_all_views() as $name => $view) {
    if (empty($view->disabled) && $view->base_table == $table) {
      $names[] = $name;
      // @todo: if ($server_deleted) $view->delete()?
    }
  }
  if ($names) {
    views_invalidate_cache();
    drupal_set_message(t('The following views were using the server %name: @views. You should disable or delete them.', array('%name' => $server->name, '@views' => implode(', ', $names))), 'warning');
  }
}

/**
 * Creates a multi-index search query on a specified search server.
 *
 * @param $id
 *   The ID or machine name of the index to execute the search on.
 * @param array $options
 *   Associative array of options configuring this query. Recognized options
 *   are:
 *   - conjunction: The type of conjunction to use for this query - either
 *     'AND' or 'OR'. 'AND' by default. This only influences the search keys,
 *     filters will always use AND by default.
 *   - 'parse mode': The mode with which to parse the $keys variable, if it
 *     is set and not already an array. See SearchApiMultiQuery::parseModes() for
 *     recognized parse modes.
 *   - languages: The languages to search for, as an array of language IDs.
 *     If not specified, all languages will be searched. Language-neutral
 *     content (LANGUAGE_NONE) is always searched.
 *   - offset: The position of the first returned search results relative to
 *     the whole result on the server.
 *   - limit: The maximum number of search results to return. -1 means no
 *     limit.
 *   - 'filter class': Can be used to change the SearchApiQueryFilterInterface
 *     implementation to use.
 *   - 'search id': A string that will be used as the identifier when storing
 *     this search in the static cache.
 *   All options are optional.
 *
 * @return SearchApiMultiQueryInterface
 *   An object for searching on the specified server.
 */
function search_api_multi_query($id, array $options = array()) {
  $server = search_api_server_load($id);
  if (!$server) {
    throw new SearchApiException(t('Unknown server with ID @id.', array('@id' => $id)));
  }
  if (!$server->supportsFeature('search_api_multi')) {
    throw new SearchApiException(t("The search server @name doesn't support multi-index searches.", array('@name' => $server->name)));
  }
  return $server->queryMultiple($options);
}

/**
 * Static store for the multi-index searches executed on the current page. Can
 * either be used to store an executed search, or to retrieve a previously
 * stored search.
 *
 * @param $search_id
 *   For pages displaying multiple searches, an optional ID identifying the
 *   search in questions. When storing a search, this is filled automatically,
 *   unless it is manually set.
 * @param SearchApiMultiQuery $query
 *   When storing an executed search, the query that was executed. NULL
 *   otherwise.
 * @param array $results
 *   When storing an executed search, the returned results as specified by
 *   SearchApiMultiQueryInterface::execute(). An empty array, otherwise.
 *
 * @return array
 *   If a search with the specified ID was executed, an array containing
 *   ($query, $results) as used in this function's parameters. If $search_id is
 *   NULL, an array of all executed searches will be returned, keyed by ID.
 */
function search_api_multi_current_search($search_id = NULL, SearchApiMultiQuery $query = NULL, array $results = array()) {
  $searches = &drupal_static(__FUNCTION__, array());

  if (isset($query)) {
    if (!isset($search_id)) {
      $search_id = $query->getOption('search id');
    }
    $base = $search_id;
    $i = 0;
    while (isset($searches[$search_id])) {
      $search_id = $base . '-' . ++$i;
    }
    $searches[$search_id] = array($query, $results);
  }

  if (isset($searches[$search_id])) {
    return $searches[$search_id];
  }
  return $searches;
}