type_user_nids.module

<?php

/**
 * @file
 * This Module creates a User Nid token  [unid].
 *    The unid token provides a Number for each node that is unique
 *    within the nodes of the same type created by the same author.
 *
 * Database definitions:
 * @code
 *   CREATE TABLE number_unids (
 *     uid int(10) unsigned NOT NULL,
 *     type int(10) unsigned NOT NULL,
 *     num_unids int(10) unsigned NOT NULL,
 *     PRIMARY KEY (uid, type)
 *   )
 *   CREATE TABLE node_unid (
 *     nid int(10) unsigned NOT NULL,
 *     unid int(10) unsigned NOT NULL,
 *     PRIMARY KEY (nid)
 *   )
 * @endcode
 */

/**
 * Internal function called for nodes that don't yet have a unid.
 *    Function generates new  unid and sets up database
 *       with new values.
 */
function _type_user_nids_generate_unid(&$node) {
  $node->unid = 1 + db_result(db_query("
    SELECT num_unids
    FROM {number_unids}
    WHERE uid = %d AND type = '%s' ",
      $node->uid,
      $node->type));
  if($node->unid != 1) {
    db_query("
      UPDATE {number_unids}
      SET num_unids = num_unids + 1
      WHERE uid = %d AND type = '%s' ",
        $node->uid,
        $node->type);
  }
// else occurs when this node's author has never previously
//    created a node of this type.
  else {db_query("
    INSERT INTO {number_unids}
    SET uid = %d, type = '%s', num_unids = 1 ",
      $node->uid,
      $node->type);
  }
  db_query("
    INSERT INTO {node_unid}
    SET nid = %d, unid = %d",
      $node->nid,
      $node->unid);
}

/**
 * Implementation of hook_nodeapi().
 */
function type_user_nids_nodeapi(&$node, $op, $a3 = NULL, $a4 = NULL) {
  switch ($op) {
    case 'load':
    case 'update':
      $node->unid = db_result(db_query("
        SELECT unid
        FROM {node_unid}
        WHERE nid = %d",
          $node->nid));
    case 'insert':
      if(!$node->unid) {
        _type_user_nids_generate_unid($node);
      }
      return array('unid' => $node->unid);
    case 'delete':
      db_query("
        DELETE FROM {node_unid}
        WHERE nid = %d",
          $node->nid);
        break;
  }
}

/**
 * Implementation of hook_node_type().
 */
function type_user_nids_node_type($op, $info) {
  switch ($op){
    case 'delete':
      db_query("
        DELETE FROM {number_unids}
        WHERE type = '%s' ",
          $info->type);
      break;
    case 'update':
      if(!empty($info->old_type) && $info->old_type != $info->type) {
        db_query("
          UPDATE {number_unids}
          SET type = '%s'
          WHERE type = '%s' ",
            $info->type, 
            $info->old_type);
      }
      break;
  }
}

/**
 * Implementation of hook_token_values().
 *   Part of Token modules API.
 *   See http://drupal.org/node/307140 for more info 
 */
function type_user_nids_token_values($type, $object = NULL, $options = array()) {
  if($type == 'node') {
    $tokens['unid'] = $object->unid;
    return $tokens;
  }
}

/**
 * Implementation of hook_token_list().
 *   Part of Token modules API.
 *   See http://drupal.org/node/307140 for more info 
 */
function type_user_nids_token_list($type = 'all') {
  if($type == 'node' || $type == 'all') {
    $tokens['node']['unid'] = t("The Type user nid.");
    return $tokens;
  }
}

/**
 * Implementation of hook_views_api().
 * This function tells views that a type_user_nids_views.inc file exists
 *      with data/program for the views module
 */
function type_user_nids_views_api() {
  return array('api' => 2.0);
}