<?php
// $Id: field_indexer.module,v 1.8 2009-03-13 19:50:33 davidlesieur Exp $

/**
 * @file
 * Indexes field content for use by modules that implement field search.
 */

/**
 * Implementation of hook_menu().
 */
function field_indexer_menu() {
  $items = array();
  $items['admin/settings/field_indexer'] = array(
    'title' => 'Field indexer',
    'access callback' => 'user_access',
    'access arguments' => array('administer search'),
    'description' => 'Enable fields for use by field searches.',
    'page callback' => 'drupal_get_form',
    'page arguments' => array('field_indexer_admin'),
    'file' => 'field_indexer.admin.inc',
  );

  return $items;
}

/**
 * Update the full-text search index for a particular field value.
 *
 * @param $nid
 *   Id of the node containing the value.
 * @param $fiid
 *   Id of the field containing the value.
 * @param $text
 *   The content of the field. Must be a piece of HTML text.
 */
function field_indexer_index($nid, $fiid, $text) {
  search_index($nid, field_indexer_type($fiid), $text);
}

/**
 * Mark all nodes for re-indexing.
 */
function field_indexer_reindex() {
  node_search('reset');
}

/**
 * Delete index entries for the specified field.
 */
function field_indexer_wipe($fiid) {
  $type = field_indexer_type($fiid);
  db_query("DELETE FROM {search_dataset} WHERE type = '%s'", $type);
  db_query("DELETE FROM {search_index} WHERE type = '%s'", $type);
  db_query("DELETE FROM {search_node_links} WHERE type = '%s'", $type);
}

/**
 * Retrieve a fresh list of fields that are exposed by modules for indexing.
 */
function field_indexer_find_fields() {
  $fields = array();
  foreach (module_implements('field_indexer_list') as $module) {
    $module_fields = module_invoke($module, 'field_indexer_list');
    foreach ($module_fields as $field) {
      // Add the field.
      $fields[_field_indexer_key($field)] = $field;
    }
  }
  return $fields;
}

/**
 * Retrieve the fields settings from the database.
 *
 * @param $status
 *   Optional status of the fields to be returned (TRUE for fields that are
 *   enabled for indexing, FALSE for fields that are not being indexed). When
 *   set, only fields with the given status are returned. When not set, all
 *   indexable fields are returned.
 * @param $namespace
 *   Optional namespace of whose fields we are interested in. When not
 *   specified, all indexable fields are returned.
 * @return
 *   An array describing the fields.
 */
function field_indexer_load_fields($status = NULL, $namespace = NULL) {
  $where = array();
  $args = array();
  if (isset($status)) {
    $where[] = 'status = %d';
    $args[] = $status ? 1 : 0;
  }
  if (isset($namespace)) {
    $where[] = "namespace = '%s'";
    $args[] = $namespace;
  }
  if (count($where)) {
    $where = ' WHERE '. implode(' AND ', $where);
  }
  else {
    $where = '';
  }
  $fields = array();
  $results = db_query('SELECT * FROM {field_indexer_map}'. $where, $args);
  while ($field = db_fetch_array($results)) {
    $fields[_field_indexer_key($field)] = $field;
  }
  return $fields;
}

/**
 * Return the index type of the specified field.
 */
function field_indexer_type($fiid) {
  return 'field_'. $fiid;
}

/**
 * Return a unique key for a field. This is useful when collecting fields whose
 * fiid have not yet been assigned.
 */
function _field_indexer_key($field) {
  return $field['namespace'] .'_'. $field['name'] .'_'. $field['extra_name'];
}