/**
 * Main function that imports, updates or deletes item or bibliographic records.
 * It can optionally take in a MARC record to bypass harvesting from the WebOPAC.
 * @param $data
 *   An associative array of data for a record, with the following keys:
 *     - 'bib_recnum' (optional)
 *       Millennium record number (b123456) for the record to process.
 *     - 'item_recnum' (optional)
 *       A Millennium record number (i123456) for the record to process.
 *       If bib_recnum is also given, it is assumed it is the bib record
 *       associated with this item.
 *     - 'marc' (optional)
 *       MARC text as it is exported from the WebOPAC.
 * @param bool $force_update (Optional) States if the function should always update existing data.
 */
function millennium_process_record(&$data, $force_update = false) {
  // Set defaults
  if (!isset($data['marc'])) {
    $data['marc'] = null;
  }
  if (!isset($data['item_recnum'])) {
    $data['item_recnum'] = null;
  }
  if (!isset($data['bib_recnum'])) {
    $data['bib_recnum'] = null;
  }
  #drupal_set_message("millennium_process_record():");
  #dpm($data);

  $type = "";
  // If only bib_recnum
  if ($data['bib_recnum'] && !$data['item_recnum']) {
    $type = "bib";
  }
  // If only item_recnum set, or if both record numbers set:
  if (
    (!$data['bib_recnum'] && $data['item_recnum']) ||
    ($data['bib_recnum'] && $data['item_recnum'])) {
    $type = "item";
  }

  switch($type) {
    case "bib":
      $result = millennium_process_bib_record(
        $data,
        $force_update
      );
      break;
    case "item":
      $result = millennium_process_item_record(
        $data,
        $force_update
      );
      break;
    default:
      watchdog("Millennium", "millennium_process_record() unknown record type: @data", array('@data' => var_export($data, TRUE)));
      return array("success" => false, "error" => "Could not determine function to call.");
  }

  if ($result["node"]) {
    $data["node"] = $result["node"];
  }
  #dpm($result);
  // Log errors
  if ($result['success'] !== true) {
    watchdog("Millennium", "millennium_process_record() failed with error @error", array('@error' => $result['error']));
  }

  return array("success" => $result['result'], 'status' => $result['status'], 'error' => $result['error']);
}

/**
 * Imports or updates Millennium item records in Drupal
 * @param array $data Millennium record information
 * @param bool $force_update (Optional) States if an existing node for that item record number should be updated.
 */
function millennium_process_item_record($data, $force_update = true) {
  #drupal_set_message("millennium_process_item_record($item_recnum, $force_update, $marc_text, $bib_recnum)");

  if ($data['base_url']) {
    $base_url = $data['base_url'];
  } else {
    return array("success" => false, "error" => "No base_url in item #" . $data['item_recnum']);
  }

  // Had we already imported this item record?
  $item_import_history = db_fetch_object(db_query(
    "SELECT * FROM {millennium_bib_item} WHERE item_recnum='%s' AND base_url = '%s'",
    $data['item_recnum'],
    $base_url
    ));
  if ($item_import_history->nid) {
    #drupal_set_message("Item $item_recnum was imported before");
    // Item was imported before.
    $status = millennium_process_item_record_prev_imported($data, $item_import_history, $force_update = true);
    $node = node_load($item_import_history->nid);
    return array(
      "success" => true,
      "status" => $status['result'],
      "node" => $node,
      #"error" => t("This item #@item_number had already been imported under nid @nid", array("@item_number" => $item_recnum, "@nid" => $item_import_history->nid))
    );
  } else {
    // Item was not imported before.
    // If not given as the function's argument, get the item's bib record number.
    if ($bib_recnum == null) {
      $result = millennium_fetch_recordpage($data['item_recnum'], $base_url, 'plain');
      $record_html = $result->data;
      $ok = preg_match('/\/record=(b[0-9]+)/si', $record_html, $matches);
      if ($ok) {
        $bib_recnum = $matches[1];
      }
    }
  }

  if (!$bib_recnum) {
    return array("success" => false, "error" => "Could not get bib_recnum for item #" . $data['item_recnum']);
  }

  // We have a bib_number by now.
  // Is there an existing node with this bib_number?
  $bib_import_history = db_fetch_object(db_query(
    "SELECT * FROM {millennium_node_bib} WHERE bib_recnum='%s' AND base_url = '%s'",
    $bib_recnum,
    $base_url
    ));
  if (!$bib_import_history->nid) {
    // New item, new bib.
    // Must the node for the bib before the item can be imported.
    $data = array('bib_recnum' => $bib_recnum, 'marc' => $marc_text);
    $result = millennium_process_bib_record($data, $force_update);
    if ($result["success"] != true) {
      return array("success" => false, "error" => "Could not create a new node for item: " . $data['item_recnum'] . " and bib: " . $data['bib_recnum']);
    } else {
      $nid = $result["node"]->nid;
    }
  } else {
    $nid = $bib_import_history->nid;
  }

  // Do actual import of new item.
  $ok = millennium_process_item_record_new_import($data, $nid);
  if ($ok) {
    return array('success' => true, 'status' => 'item_created');
  } else {
    return array('success' => false, 'error' => "Could not create a new item for item $item_recnum");
  }
}