membership_entity.module

<?php

/**
 * @file
 * Allows users to create membership entities.
 */

/**
 * Membership status codes.
 */
define('MEMBERSHIP_ENTITY_EXPIRED', 0);
define('MEMBERSHIP_ENTITY_ACTIVE', 1);
define('MEMBERSHIP_ENTITY_CANCELLED', 2);
define('MEMBERSHIP_ENTITY_PENDING', 3);

/**
 * Retrieve a list of membership status options.
 */
function membership_entity_get_status_list() {
  return array(
    MEMBERSHIP_ENTITY_EXPIRED => t('Expired'),
    MEMBERSHIP_ENTITY_ACTIVE => t('Active'),
    MEMBERSHIP_ENTITY_CANCELLED => t('Cancelled'),
    MEMBERSHIP_ENTITY_PENDING => t('Pending'),
  );
}

/**
 * Implements hook_help().
 */
function membership_entity_help($path, $arg) {
  // @TODO add help documentation
}

/**
 * Implements hook_entity_info().
 */
function membership_entity_entity_info() {
  $info['membership_entity'] = array(
    'label' => t('Membership'),
    'module' => 'membership_entity',
    'plural label' => t('Memberships'),
    'entity class' => 'MembershipEntity',
    'controller class' => 'MembershipEntityController',
    'base table' => 'membership_entity',
    'revision table' => 'membership_entity_revision',
    'label callback' => 'entity_class_label',
    'uri callback' => 'entity_class_uri',
    'access callback' => 'membership_entity_access',
    'fieldable' => TRUE,
    'entity keys' => array(
      'id' => 'mid' ,
      'bundle' => 'type',
      'label' => 'member_id',
      'revision' => 'revision_id',
    ),
    'bundle keys' => array(
      'bundle' => 'type',
    ),
    'static cache' => TRUE,
    'bundles' => array(
      'membership' => array(
        'label' => t('Membership'),
        'admin' => array(
          'path' => 'admin/memberships/types/manage/membership',
          'access arguments' => array('administer memberships'),
          'bundle argument' => 4,
        ),
      ),
    ),
    'view modes' => array(
      'full' => array(
        'label' => t('Full Membership'),
        'custom settings' => FALSE,
      ),
      'account' => array(
        'label' => t('User account page'),
        'custom settings' => FALSE,
      ),
    ),
    'metadata controller class' => 'MembershipEntityMetadataController',
    'views controller class' => 'MembershipEntityViewsController',
  );

  return $info;
}

/**
 * Implements hook_permission().
 */
function membership_entity_permission() {
  $permissions = array(
    'administer memberships' => array(
      'title' => t('Administer memberships'),
      'restrict access' => TRUE,
    ),
  );

  if (!module_exists('membership_entity_type')) {
    $permissions['membership join'] = array(
      'title' => t('Join @site', array('@site' => variable_get('site_name', ''))),
    );
    $permissions['membership view any membership'] = array(
      'title' => t('View any membership.'),
    );
    $permissions['membership view own membership'] = array(
      'title' => t('View own membership.'),
    );
    $permissions['membership edit any membership'] = array(
      'title' => t('Edit any membership.'),
    );
    $permissions['membership edit own membership'] = array(
      'title' => t('Edit own membership.'),
    );
    $permissions['membership delete any membership'] = array(
      'title' => t('Delete any membership.'),
      'restrict access' => TRUE,
    );
    $permissions['membership delete own membership'] = array(
      'title' => t('Delete own membership.'),
      'restrict access' => TRUE,
    );
  }

  return $permissions;
}

/**
 * Membership entity access callback.
 *
 * @param string $op
 *   The membership operations.
 * @param $membership
 *   The membership object or type name if $op == 'join'.
 * @param object $account
 *   The user account to check access. Defaults to logged in user.
 *
 * @return bool
 *   TRUE if the user has access for the given operation.
 */
function membership_entity_access($op, $membership = NULL, $account = NULL) {
  if (user_access('administer memberships', $account)) {
    return TRUE;
  }

  // Allow modules to grant or deny access.
  $access = module_invoke_all('membership_entity_access', $op, $membership, $account);

  // Grant access if a module grants access and no one denies access.
  if (in_array(FALSE, $access, TRUE)) {
    return FALSE;
  }
  elseif (in_array(TRUE, $access, TRUE)) {
    return TRUE;
  }
  return FALSE;
}

/**
 * Implements hook_membership_entity_access().
 */
function membership_entity_membership_entity_access($op, $membership = NULL, $account = NULL) {
  $user = isset($account) ? $account : $GLOBALS['user'];

  // Join page access.
  if ($op == 'join') {
    $type = str_replace('-', '_', $membership);
    // Check if a membership already exists for this user.
    $exists = (bool) db_query('SELECT mid FROM {membership_entity} WHERE uid = :uid AND uid <> 0 AND type = :type', array(':uid' => $user->uid, ':type' => $type))->rowCount();
    if (!$exists && user_access("$type join", $user)) {
      return TRUE;
    }
    return FALSE;
  }

  if (is_object($membership) && $type_name = $membership->type) {
    if (user_access("$type_name $op any membership", $user)) {
      return TRUE;
    }

    if (user_access("$type_name $op own membership", $user) && $membership->uid == $user->uid) {
      return TRUE;
    }

    // Secondary member access.
    $results = db_query('SELECT mid FROM {membership_entity_secondary_member} WHERE uid = :uid', array(':uid' => $user->uid))->fetchAllAssoc('mid');
    if (!empty($results) && in_array($membership->mid, array_keys($results))) {
      // Can secondary members edit the membership?
      $bundle_settings = membership_entity_get_bundle_settings($type_name);
      if ($op == 'edit' && $bundle_settings['all_edit'] && user_access("$type_name edit own membership", $user)) {
        return TRUE;
      }

      // Can secondary members view the membership?
      if ($op == 'view' && user_access("$type_name view own membership", $user)) {
        return TRUE;
      }
    }
  }
}

/**
 * Access callback for the modal register form.
 *
 * @see user_register_access()
 */
function membership_entity_modal_register_access() {
  return user_access('administer users') || variable_get('user_register', USER_REGISTER_VISITORS_ADMINISTRATIVE_APPROVAL);
}

/**
 * Implements hook_menu().
 */
function membership_entity_menu() {
  // Placeholder menu items for the memberships view.
  $items['admin/memberships'] = array(
    'title' => 'Memberships',
    'access arguments' => array('administer memberships'),
    'type' => MENU_NORMAL_ITEM,
  );
  $items['admin/memberships/list'] = array(
    'title' => 'List',
    'type' => MENU_DEFAULT_LOCAL_TASK,
  );

  $items['admin/memberships/add'] = array(
    'title' => 'Add a membership',
    'page callback' => 'drupal_get_form',
    'page arguments' => array('membership_entity_edit_form'),
    'access arguments' => array('administer memberships'),
    'type' => MENU_LOCAL_ACTION,
    'file' => 'membership_entity.pages.inc',
  );

  if (!module_exists('membership_entity_type')) {
    $items['admin/memberships/types/manage/membership'] = array(
      'title' => 'Configure',
      'page callback' => 'drupal_get_form',
      'page arguments' => array('membership_entity_settings_form'),
      'access arguments' => array('administer memberships'),
      'file' => 'membership_entity.pages.inc',
      'type' => MENU_LOCAL_TASK,
      'weight' => 99,
    );

    $items['admin/memberships/types/manage/membership/settings'] = array(
      'title' => 'Settings',
      'type' => MENU_DEFAULT_LOCAL_TASK,
    );
  }

  $items['user/join'] = array(
    'title' => 'Join',
    'page callback' => 'drupal_get_form',
    'page arguments' => array('membership_entity_join_form'),
    'access callback' => 'membership_entity_access',
    'access arguments' => array('join', 'membership'),
    'type' => MENU_LOCAL_TASK | MENU_NORMAL_ITEM,
    'weight' => -9999,
    'menu_name' => 'user-menu',
    'file' => 'membership_entity.pages.inc',
  );

  $items['membership/%membership_entity'] = array(
    'title callback' => 'membership_entity_page_title',
    'title arguments' => array(1),
    'page callback' => 'membership_entity_view',
    'page arguments' => array(1),
    'access callback' => 'membership_entity_access',
    'access arguments' => array('view', 1),
  );
  $items['membership/%membership_entity/view'] = array(
    'title' => 'View',
    'type' => MENU_DEFAULT_LOCAL_TASK,
    'weight' => -10,
  );
  $items['membership/%membership_entity/edit'] = array(
    'title' => 'Edit',
    'page callback' => 'membership_entity_edit',
    'page arguments' => array(1),
    'access callback' => 'membership_entity_access',
    'access arguments' => array('edit', 1),
    'weight' => 0,
    'type' => MENU_LOCAL_TASK,
    'context' => MENU_CONTEXT_PAGE | MENU_CONTEXT_INLINE,
    'file' => 'membership_entity.pages.inc',
  );
  $items['membership/%membership_entity/delete'] = array(
    'title' => 'Delete',
    'page callback' => 'drupal_get_form',
    'page arguments' => array('membership_entity_delete_confirm', 1),
    'access callback' => 'membership_entity_access',
    'access arguments' => array('delete', 1),
    'weight' => 2,
    'type' => MENU_LOCAL_TASK,
    'context' => MENU_CONTEXT_INLINE,
    'file' => 'membership_entity.pages.inc',
  );

  // Modal register form.
  $items['membership_entity/%ctools_js/register/%'] = array(
    'title' => 'Register',
    'page callback' => 'membership_entity_modal_register',
    'page arguments' => array(1, 3),
    'access callback' => 'membership_entity_modal_register_access',
    'file' => 'membership_entity.pages.inc',
    'type' => MENU_CALLBACK,
  );

  // Add support for devel generate.
  if (module_exists('devel_generate')) {
    $items['admin/config/development/generate/membership-entity'] = array(
      'title' => 'Generate memberships',
      'description' => 'Generate a given number of memberships. Optionally delete current memberships.',
      'page callback' => 'drupal_get_form',
      'page arguments' => array('membership_entity_devel_generate_memberships_form'),
      'access arguments' => array('administer memberships'),
      'type' => MENU_NORMAL_ITEM,
      'file' => 'membership_entity.devel.inc',
    );
  }

  return $items;
}

/**
 * Implements hook_menu_alter().
 */
function membership_entity_menu_alter(&$items) {
  // Override user_register_access() to check if a membership is required.
  $items['user/register']['access callback'] = 'membership_entity_register_access';
}

/**
 * Check if a membership is required.
 */
function membership_entity_register_access() {
  return !variable_get('membership_entity_required', FALSE) && user_register_access();
}

/**
 * Implements hook_menu_link_alter().
 */
function membership_entity_menu_link_alter(&$link) {
  // Force the Join link to appear on the top level of the 'user-menu' menu.
  if ($link['link_path'] == 'user/join' && $link['module'] == 'system' && empty($link['customized'])) {
    $link['plid'] = 0;
  }
}

/**
 * Title callback for a membership page.
 */
function membership_entity_page_title($membership) {
  $statuses = membership_entity_get_status_list();
  return t('Membership @member_id@status', array(
    '@member_id' => $membership->member_id,
    '@status' => ($membership->status != MEMBERSHIP_ENTITY_ACTIVE) ? ' (' . $statuses[$membership->status] . ')' : '',
  ));
}

/**
 * Implements hook_admin_paths().
 */
function membership_entity_admin_paths() {
  return array(
    'membership/*/delete' => TRUE,
    'membership/*/edit' => TRUE,
  );
}

/**
 * Implements hook_pathauto().
 */
function membership_entity_pathauto($op) {
  if ($op == 'settings') {
    $settings = array(
      'module' => 'membership_entity',
      'groupheader' => t('Membership Paths'),
      'patterndescr' => t('Default path pattern (applies to all membership types with blank patterns below.)'),
      'patterndefault' => 'membership/[membership_entity:mid]',
      'token_type' => 'membership_entity',
      'bulkname' => t('Bulk Update Membership Paths'),
      'bulkdescr' => t('Generate aliases for all existing membership items which do not already have aliases.'),
    );

    // Get membership types.
    foreach (membership_entity_get_bundles() as $machine_name => $type) {
      $settings['patternitems'][$machine_name] = t('Pattern for all %label paths', array('%label' => $type->label));
    }

    return (object) $settings;
  }
}

/**
 * Implements hook_membership_entity_insert().
 */
function membership_entity_membership_entity_insert($membership) {
  membership_entity_update_alias($membership, 'insert');
}

/**
 * Implements hook_membership_entity_update().
 */
function membership_entity_membership_entity_update($membership) {
  membership_entity_update_alias($membership, 'update');
}

/**
 * Implements hook_membership_entity_delete().
 */
function membership_entity_membership_entity_delete($membership) {
  if (module_exists('pathauto')) {
    pathauto_entity_path_delete_all('membership_entity', $membership, "membership/{$membership->mid}");
  }
}

/**
 * Update a membership alias.
 */
function membership_entity_update_alias(MembershipEntity $membership, $op, $options = array()) {
  $uri = entity_uri('membership_entity', $membership);
  if (!module_exists('pathauto')) {
    return $uri['path'];
  }

  $options += array('language' => pathauto_entity_language('membership_entity', $membership));
  if (!pathauto_pattern_load_by_entity('membership_entity', $membership->type, $options['language'])) {
    return;
  }
  module_load_include('inc', 'pathauto');
  pathauto_create_alias('membership_entity', $op, $uri['path'], array('membership_entity' => $membership), $membership->type, $options['language']);
}

/**
 * Implements hook_theme().
 */
function membership_entity_theme() {
  $theme_hooks = array(
    'membership_entity' => array(
      'render element' => 'membership',
      'template' => 'membership-entity',
    ),
  );

  foreach ($theme_hooks as $hook => $info) {
    $theme_hooks[$hook]['file'] = 'membership_entity.theme.inc';
  }

  return $theme_hooks;
}

/**
 * Implements hook_user_view().
 *
 * Add membership data to the user page.
 */
function membership_entity_user_view($account, $view_mode, $langcode) {
  if ($view_mode == 'full' && $memberships = membership_entity_load_by_user($account)) {
    foreach ($memberships as $type => $membership) {
      if (membership_entity_access('view', $membership)) {
        $account->content['memberships'][$type] = membership_entity_view($membership, 'account', $langcode);
      }
    }
  }
}

/**
 * Menu callback: Display a membership.
 */
function membership_entity_view($membership, $view_mode = 'full', $langcode = NULL) {
  if (!isset($langcode)) {
    $langcode = $GLOBALS['language']->language;
  }

  $entity_type = 'membership_entity';
  $membership->content = array();

  // Allow modules to change the view mode.
  $context = array(
    'entity_type' => $entity_type,
    'entity' => $membership,
    'langcode' => $langcode,
  );
  drupal_alter('entity_view_mode', $view_mode, $context);

  // Add the primary membership on full membership page.
  if ($view_mode == 'full') {
    $account = user_load($membership->uid);
    $membership->content['uid'] = array(
      'label' => array(
        '#theme_wrappers' => array('container'),
        '#attributes' => array('class' => array('membership-entity-label')),
        '#markup' => t('Primary Member:!nbsp', array('!nbsp' => '&nbsp')),
      ),
      'link' => array(
        '#type' => 'link',
        '#title' => format_username($account),
        '#href' => 'user/' . $account->uid,
        '#options' => array(
          'attributes' => array('class' => array('membership-entity-primary-member')),
          'html' => FALSE,
        ),
      ),
    );
  }

  if (!empty($membership->secondary_members)) {
    $links = array();
    foreach ($membership->secondary_members as $delta => $uid) {
      $links[$delta] = array(
        'title' => format_username(user_load($uid)),
        'href' => 'user/' . $uid,
      );
    }

    $membership->content['secondary_members'] = array(
      'label' => array(
        '#theme_wrappers' => array('container'),
        '#attributes' => array('class' => array('membership-entity-label')),
        '#markup' => format_plural(count($links), 'Secondary Member:', 'Secondary Members:') . '&nbsp',
      ),
    );
    if (count($links) == 1) {
      $link = reset($links);
      $membership->content['secondary_members']['links'] = array(
        '#type' => 'link',
        '#title' => $link['title'],
        '#href' => $link['href'],
        '#options' => array(
          'attributes' => array('class' => array('membership-entity-secondary-members')),
          'html' => FALSE,
        ),
      );
    }
    else {
      $membership->content['secondary_members']['links'] = array(
        '#theme' => 'links',
        '#links' => $links,
        '#attributes' => array('class' => array('membership-entity-secondary-members')),
      );
    }
  }

  // Build custom field content.
  field_attach_prepare_view('membership_entity', array($membership->mid => $membership), $view_mode, $langcode);
  entity_prepare_view('membership_entity', array($membership->mid => $membership), $langcode);
  $membership->content += field_attach_view('membership_entity', $membership, $view_mode, $langcode);

  $membership->content['links'] = array(
    '#theme' => 'links__membership_entity',
    '#pre_render' => array('drupal_pre_render_links'),
    '#attributes' => array('class' => array('links', 'inline')),
    '#weight' => 99,
  );
  if ($view_mode == 'account') {
    // Display the membership in a fieldset on user account pages.
    $membership->content += array(
      '#theme_wrappers' => array('fieldset'),
      '#title' => t('Membership @member_id', array(
        '@member_id' => $membership->member_id,
      )),
    );

    $links = array();
    $links['view'] = array(
      'title' => t('View full membership'),
      'href' => 'membership/' . $membership->mid,
      'attributes' => array(
        'title' => t('View membership @member_id.', array('@member_id' => $membership->member_id)),
      ),
      'html' => FALSE,
    );

    if (membership_entity_access('edit', $membership)) {
      $links['edit'] = array(
        'title' => t('Edit membership'),
        'href' => 'membership/' . $membership->mid . '/edit',
        'attributes' => array(
          'title' => t('Edit membership @member_id.', array('@member_id' => $membership->member_id)),
        ),
        'html' => FALSE,
      );
    }

    $membership->content['links']['membership_entity'] = array(
      '#theme' => 'links__membership_entity__membership_entity',
      '#links' => $links,
      '#attributes' => array('class' => array('links', 'inline')),
    );
  }

  module_invoke_all('membership_entity_view', $membership, $view_mode, $langcode);
  module_invoke_all('entity_view', $membership, 'membership_entity', $view_mode, $langcode);

  $membership->content += array('#view_mode' => $view_mode);

  $build = $membership->content;
  unset($membership->content);

  $build += array(
    '#theme' => 'membership_entity',
    '#membership_entity' => $membership,
    '#view_mode' => $view_mode,
    '#language' => $langcode,
  );

  // Invoke view and alter hooks.
  $type = 'membership_entity';
  drupal_alter(array('membership_entity_view', 'entity_view'), $build, $type);
  return $build;
}

/**
 * Implements hook_field_info_alter().
 */
function membership_entity_field_info_alter(&$info) {
  // Add the 'membership_entity_join_form' instance setting to all field types.
  foreach ($info as $field_type => $field_type_info) {
    $info[$field_type]['instance_settings']['membership_entity_join_form'] = FALSE;
  }
}

/**
 * Implements hook_field_extra_fields().
 */
function membership_entity_field_extra_fields() {
  if (!module_exists('membership_entity_type')) {
    $fields['membership_entity']['membership'] = array(
      'form' => array(
        'user' => array(
          'label' => t('User Information'),
          'description' => t('User account fields on the join form.'),
          'weight' => -10,
        ),
        'membership' => array(
          'label' => t('Membership Information'),
          'description' => t('Member ID, primary and secondary members, status, etc.'),
          'weight' => 0,
        ),
      ),
    );
  }

  $fields['user']['user'] = array(
    'display' => array(
      'memberships' => array(
        'label' => t('Memberships'),
        'description' => t('Memberships the user belongs to.'),
        'weight' => 9999,
      ),
    ),
  );

  return $fields;
}

/**
 * Implements hook_form_FORM_ID_alter() for user_admin_settings().
 *
 * Add membership options to the account settings form.
 */
function membership_entity_form_user_admin_settings_alter(&$form, &$form_state, $form_id) {
  $form['registration_cancellation']['membership_entity_required'] = array(
    '#type' => 'checkbox',
    '#title' => t('Require a membership when a visitor creates an account.'),
    '#default_value' => variable_get('membership_entity_required', FALSE),
    '#description' => t('New users will be required to create a membership during registration. With this setting enabled, users must complete the join form to create an account.'),
    '#weight' => 10,
  );

  // Show our checkbox above the cancellation settings.
  if (!empty($form['registration_cancellation']['user_cancel_method'])) {
    $form['registration_cancellation']['user_cancel_method']['#weight'] = 99;
  }
}

/**
 * Implements hook_form_FORM_ID_alter() for field_uid_field_edit_form().
 *
 * Add a checkbox for the 'membership_entity_join_form' setting.
 */
function membership_entity_form_field_ui_field_edit_form_alter(&$form, &$form_state, $form_id) {
  $instance = $form['#instance'];
  if (in_array($instance['entity_type'], array('membership_entity', 'membership_entity_term')) && !$form['#field']['locked']) {
    $form['instance']['settings']['membership_entity_join_form'] = array(
      '#type' => 'checkbox',
      '#title' => t('Display on join form.'),
      '#description' => t("This is compulsory for 'required' fields."),
      '#default_value' => $instance['settings']['membership_entity_join_form'] || $instance['required'],
      '#weight' => $form['instance']['required']['#weight'] + .1,
      '#states' => array(
        'enabled' => array('input[name="instance[required]"]' => array('checked' => FALSE)),
      ),
      '#attached' => array(
        'js' => array(drupal_get_path('module', 'membership_entity') . '/js/membership-entity.js'),
      ),
    );

    array_unshift($form['#submit'], 'membership_entity_form_field_ui_field_edit_form_submit');
  }
}

/**
 * Additional submit handler for the 'Edit field instance' form.
 *
 * Make sure the 'membership_entity_join_form' setting is set for
 * required fields.
 */
function membership_entity_form_field_ui_field_edit_form_submit($form, &$form_state) {
  $instance = $form_state['values']['instance'];
  if (!empty($instance['required'])) {
    form_set_value($form['instance']['settings']['membership_entity_join_form'], 1, $form_state);
  }
}

/**
 * Custom pre render to handle non-field elements.
 *
 * _field_extra_fields_pre_render() requires #type = 'form' in order to
 * respect extra field settings in hook_field_extra_fields(). This seems
 * stupid. We'll just have to do it ourselves.
 */
function _membership_entity_extra_fields_pre_render($elements) {
  $entity_type = $elements['#entity_type'];
  $bundle = $elements['#bundle'];
  $extra_fields = field_info_extra_fields($entity_type, $bundle, 'form');
  foreach ($extra_fields as $name => $settings) {
    if (isset($elements[$name])) {
      $elements[$name]['#weight'] = $settings['weight'];
    }
  }
  return $elements;
}

/**
 * Custom Field API validate handler.
 *
 * The entity_form_field_validate() assumes the entity form elements are at the
 * top level of the $form_state['values'] without regard to $form['#parents'].
 * This seems stupid. We'll just have to do it ourselves.
 */
function _membership_entity_form_field_validate($entity_type, $form, &$form_state) {
  $path = array_merge($form['#parents']);
  $key_exists = NULL;
  $values = drupal_array_get_nested_value($form_state['values'], $path, $key_exists);
  if ($key_exists) {
    $pseudo_entity = (object) $values;
    field_attach_form_validate($entity_type, $pseudo_entity, $form, $form_state);
  }
}

/**
 * Copies values to enitty properties.
 *
 * The entity_form_submit_build_entity() assumes the entity form elements are at
 * the top level of the $form_state['values'] without regard to
 * $form['#parents']. This seems stupid. We'll just have to do it ourselves.
 */
function _membership_entity_form_submit_build_entity($entity_type, $entity, $form, &$form_state) {
  $info = entity_get_info($entity_type);
  list(, , $bundle) = entity_extract_ids($entity_type, $entity);

  $path = array_merge($form['#parents']);
  $key_exists = NULL;
  $values = drupal_array_get_nested_value($form_state['values'], $path, $key_exists);
  if ($key_exists) {
    $values_excluding_fields = $info['fieldable'] ? array_diff_key($values, field_info_instances($entity_type, $bundle)) : $values;
    foreach ($values_excluding_fields as $key => $value) {
      $entity->$key = $value;
    }

    // Invoke all specified builders for copying form values to entity
    // properties.
    if (isset($form['#entity_builders'])) {
      foreach ($form['#entity_builders'] as $function) {
        $function($entity_type, $entity, $form, $form_state);
      }
    }

    // Copy field values to the entity.
    if ($info['fieldable']) {
      field_attach_submit($entity_type, $entity, $form, $form_state);
    }
  }
}

/**
 * Wrapper to load membership bundles.
 *
 * This provides a simple list of available membership bundles without the need
 * to check if the membership_entity_type module is enabled.
 *
 * @param string $bundle
 *   (optional) Return info about a specific bundle. If not provided, return
 *   info about all bundles.
 */
function membership_entity_get_bundles($bundle = NULL) {
  if (module_exists('membership_entity_type')) {
    return membership_entity_type_get_types($bundle);
  }

  $bundles['membership'] = (object) array(
    'id' => 1,
    'type' => 'membership',
    'label' => t('Membership'),
    'description' => t('A simple membership'),
    'data' => variable_get('membership_entity_settings', array()),
  );
  if (isset($bundle)) {
    return isset($bundles[$bundle]) ? $bundles[$bundle] : FALSE;
  }
  return $bundles;
}

/**
 * Load bundle settings for a membership.
 *
 * @param string $bundle
 *   The membership bundle to load settings.
 *
 * @return array
 *   An array of bundle settings or FALSE if not configured.
 */
function membership_entity_get_bundle_settings($bundle = 'membership') {
  if (module_exists('membership_entity_type')) {
    $type = membership_entity_type_load($bundle);
    $data = $type->data;
  }
  else {
    $data = variable_get('membership_entity_settings', array());
  }

  $data['status'] = !empty($data);

  // Apply defaults.
  $data += module_invoke_all('membership_entity_bundle_settings_defaults');
  return $data;
}

/**
 * Implements hook_membership_entity_bundle_settings_defaults().
 */
function membership_entity_membership_entity_bundle_settings_defaults() {
  return array(
    'cardinality' => '1',
    'show_on_profile' => 1,
    'all_edit' => 0,
    'primary_role' => '',
    'secondary_role' => '',
    'member_id_format' => 'membership_entity_numeric_member_id',
    'member_id_settings' => array(),
  );
}

/**
 * Return the next available member id.
 *
 * @param MembershipEntity $membership
 *   The membership object to create a new member id. Used for tokens.
 *
 * @return string
 *   The next available member id for the membership.
 */
function membership_entity_next_member_id(MembershipEntity $membership) {
  $data = membership_entity_get_bundle_settings($membership->type);
  return _membership_entity_member_id_get_instance($data['member_id_format'], $data['member_id_settings'])
    ->next($membership);
}

/**
 * Implements hook_ctools_plugin_type().
 */
function membership_entity_ctools_plugin_type() {
  return array(
    'member_id' => array(
      'cache' => TRUE,
      'use hooks' => TRUE,
      'hook' => 'membership_entity_member_id_info',
      'classes' => array('class'),
      'process' => 'membership_entity_member_id_plugin_process',
    ),
  );
}

/**
 * CTools plugin process callback.
 */
function membership_entity_member_id_plugin_process(&$plugin, $info) {
  $plugin += array(
    'description' => '',
  );
}

/**
 * Get metadata for member id plugins.
 *
 * @param int $id
 *   (optional) Return metadata on a specific member_id plugin.
 */
function membership_entity_get_member_id($id = NULL) {
  ctools_include('plugins');
  return ctools_get_plugins('membership_entity', 'member_id', $id);
}

/**
 * Helper to retrieve a member id plugin instance.
 *
 * @return MembershipEntityMemberIdInterface
 *   MembershipEntityMemberIDInterface object instance.
 */
function _membership_entity_member_id_get_instance($id, $settings = array()) {
  $instances = &drupal_static(__FUNCTION__);

  if (!isset($instances[$id])) {
    $plugin = membership_entity_get_member_id($id);
    $class = ctools_plugin_get_class($plugin, 'class');
    $class = class_exists($class) ? $class : 'MembershipEntityMemberIdBroken';
    $instances[$id] = new $class($settings);

    // Check that plugin has implemented MembershipEntityMemberIdInterface.
    if (!in_array('MembershipEntityMemberIdInterface', class_implements($instances[$id]))) {
      $instances[$id] = new MembershipEntityMemberIdBroken($settings);
    }
  }

  return $instances[$id];
}

/**
 * Implements hook_membership_entity_member_id_info().
 */
function membership_entity_membership_entity_member_id_info() {
  $info['membership_entity_numeric_member_id'] = array(
    'title' => t('Numeric ID'),
    'description' => t('A simple incrementing numeric member id.'),
    'class' => 'MembershipEntityNumericMemberId',
    'path' => drupal_get_path('module', 'membership_entity') . '/plugins/member_id',
  );
  if (module_exists('token')) {
    $info['membership_entity_token_member_id'] = array(
      'title' => t('Token ID'),
      'description' => t('A member id built with tokens.'),
      'class' => 'MembershipEntityTokenMemberId',
      'path' => drupal_get_path('module', 'membership_entity') . '/plugins/member_id',
    );
  }
  return $info;
}

/**
 * Implements hook_user_cancel().
 */
function membership_entity_user_cancel($edit, $account, $method) {
  switch ($method) {
    case 'user_cancel_block_unpublish':
      $memberships = membership_entity_load_by_user($account->uid);
      foreach ($memberships as $membership) {
        $membership->status = MEMBERSHIP_ENTITY_CANCELLED;
        membership_entity_save($membership);
      }
      break;

    case 'user_cancel_reassign':
      membership_entity_user_delete($account);
      break;
  }
}

/**
 * Implements hook_user_delete().
 */
function membership_entity_user_delete($account) {
  // Delete primary memberships.
  $memberships = membership_entity_load_by_user($account->uid);
  foreach ($memberships as $membership) {
    membership_entity_delete($membership->mid);
  }

  // Delete secondary member records.
  db_delete('membership_entity_secondary_member')
    ->condition('uid', $account->uid)
    ->execute();
}

/**
 * Implements hook_element_info().
 */
function membership_entity_element_info() {
  return array(
    'membership_entity_member_select' => array(
      '#input' => TRUE,
      '#title' => '',
      '#description' => '',
      '#default_value' => array(),
      '#disabled' => FALSE,
      '#cardinality' => 1,
      '#required' => FALSE,
      '#autocomplete_path' => 'user/autocomplete',
      '#process' => array('membership_entity_member_select_process'),
      '#element_validate' => array('membership_entity_member_select_validate'),
    ),
  );
}

/**
 * Default value callback for membership_entity_member_select.
 */
function form_type_membership_entity_member_select_value($element, $input, &$form_state) {
  if ($input === FALSE && !empty($element['#default_value'])) {
    foreach ($element['#default_value'] as $delta => $uid) {
      // Expand the raw uid into username.
      $value[$delta] = array(
        'value' => db_query_range('SELECT name FROM {users} WHERE uid = :uid', 0, 1, array(':uid' => $uid))->fetchField(),
        '_weight' => $delta,
      );
    }
    return $value;
  }
  return $input;
}

/**
 * Process callback for the member select element.
 */
function membership_entity_member_select_process($element, &$form_state, $complete_form) {
  // Include the CTools tools and javascript that we need.
  ctools_include('ajax');
  ctools_include('modal');
  ctools_modal_add_js();

  $multiple = ($element['#cardinality'] > 1 || $element['#cardinality'] == FIELD_CARDINALITY_UNLIMITED);
  $wrapper_id = drupal_html_id($element['#id'] . '-add-more-wrapper');

  if (empty($form_state['items_count'][$element['#name']])) {
    $form_state['items_count'][$element['#name']] = count($element['#value']);
  }

  if ($element['#cardinality'] == FIELD_CARDINALITY_UNLIMITED) {
    $max = $form_state['items_count'][$element['#name']];
  }
  else {
    $max = $element['#cardinality'] - 1;
  }

  if ($multiple) {
    $field_element = array(
      '#theme' => 'field_multiple_value_form',
      '#field_name' => $element['#name'],
      '#prefix' => '<div id="' . $wrapper_id . '">',
      '#suffix' => '</div>',
      '#max_delta' => $max,
      '#tree' => TRUE,
    );
  }
  else {
    // Single value is displayed in a fieldset.
    $field_element = array(
      '#prefix' => '<label>' . $element['#title'] . '</label>',
      '#tree' => TRUE,
    );
  }

  $field_element += $element;
  for ($delta = 0; $delta <= $max; $delta++) {
    $id = drupal_html_id($element['#id'] . '_' . $delta);
    $item['value'] = array(
      '#delta' => $delta,
      '#weight' => $delta,
      '#type' => 'textfield',
      '#title' => t('Select an existing account'),
      '#disabled' => $element['#disabled'],
      '#description' => filter_xss($element['#description']),
      '#autocomplete_path' => $element['#autocomplete_path'],
      '#default_value' => isset($element['#default_value'][$delta]) ? $element['#default_value'][$delta] : '',
      '#value_callback' => 'membership_entity_uid_value',
      // Only the first item should be required.
      '#required' => $delta == 0 && $element['#required'],
      '#id' => $id,
    );

    // Add the "Create a new account" button.
    if (!$element['#disabled'] && membership_entity_modal_register_access()) {
      $item['value']['#field_suffix'] = ' or ' . ctools_modal_text_button(t('Create a new account'), 'membership_entity/nojs/register/' . $id, t('Create a new account.'), 'button');
    }

    if ($element['#cardinality'] > 1 || $element['#cardinality'] == FIELD_CARDINALITY_UNLIMITED) {
      // We name the element '_weight' to avoid clashing with elements
      // defined by widget.
      $item['_weight'] = array(
        '#type' => 'weight',
        '#title' => t('Weight for row @number', array('@number' => $delta + 1)),
        '#title_display' => 'invisible',
        '#delta' => $max,
        '#default_value' => $delta,
        '#weight' => 100,
      );
    }

    $field_element[$delta] = $item;
  }

  // Add the "add more" button.
  if ($element['#cardinality'] == FIELD_CARDINALITY_UNLIMITED && empty($form_state['programmed'])) {
    $field_element['add_more'] = array(
      '#type' => 'submit',
      '#name' => strtr($element['#id'], '-', '_') . '_add_more',
      '#value' => t('Add another'),
      '#field_name' => $element['#name'],
      '#attributes' => array('class' => array('field-add-more-submit')),
      '#limit_validation_errors' => array(),
      '#submit' => array('membership_entity_member_select_add_more_submit'),
      '#ajax' => array(
        'callback' => 'membership_entity_member_select_add_more_js',
        'wrapper' => $wrapper_id,
        'effect' => 'fade',
      ),
    );
  }

  return $field_element;
}

/**
 * Submit handler for the "Add another" button of a member field.
 */
function membership_entity_member_select_add_more_submit($form, &$form_state) {
  $button = $form_state['triggering_element'];
  $form_state['items_count'][$button['#field_name']]++;
  $form_state['rebuild'] = TRUE;
}

/**
 * Ajax callback to add another member select widget.
 *
 * @see membership_entity_member_select_add_more_submit()
 */
function membership_entity_member_select_add_more_js($form, $form_state) {
  $button = $form_state['triggering_element'];

  // Go one level up in the form, to the widgets container.
  $element = drupal_array_get_nested_value($form, array_slice($button['#array_parents'], 0, -1));

  if ($element['#cardinality'] != FIELD_CARDINALITY_UNLIMITED) {
    return;
  }

  // Add a DIV around the delta receiving the Ajax effect.
  $delta = $element['#max_delta'];
  $element[$delta]['#prefix'] = '<div class="ajax-new-content">' . (isset($element[$delta]['#prefix']) ? $element[$delta]['#prefix'] : '');
  $element[$delta]['#suffix'] = (isset($element[$delta]['#suffix']) ? $element[$delta]['#suffix'] : '') . '</div>';

  return $element;
}

/**
 * Element validate callback for the membership_entity_member_select element.
 */
function membership_entity_member_select_validate($element, &$form_state) {
  $values = array();
  if (!empty($element['#value'])) {
    foreach ($element['#value'] as $delta => $value) {
      if (!is_numeric($delta)) {
        continue;
      }

      if (!empty($value['value'])) {
        $name = $value['value'];
        if ($uid = db_query('SELECT uid FROM {users} WHERE name = :name', array(':name' => $name))->fetchField()) {
          // Save the value as a uid instead of username.
          $values[$delta] = $uid;
        }
        else {
          form_error($element[$delta], t('Could not find an account with the username %name', array('%name' => $name)));
        }
      }
    }
  }

  form_set_value($element, $values, $form_state);
  return $element;
}

/**
 * Value callback to display the username of a given user.
 */
function membership_entity_uid_value($element, $input = FALSE, $form_state = array()) {
  if ($input === FALSE && !empty($element['#default_value'])) {
    // Expand the raw uid into username.
    $uid = $element['#default_value'];
    return db_query('SELECT name FROM {users} WHERE uid = :uid LIMIT 1', array(':uid' => $uid))->fetchField();
  }
}

/**
 * Implements hook_action_info().
 */
function membership_entity_action_info() {
  $info['membership_entity_cancel_action'] = array(
    'type' => 'membership_entity',
    'label' => t('Cancel membership'),
    'configurable' => FALSE,
    'behavior' => array('changes_property'),
  );

  if (module_exists('pathauto')) {
    $info['membership_entity_pathauto_update_action'] = array(
      'type' => 'membership_entity',
      'label' => t('Update membership alias'),
      'configurable' => FALSE,
    );
  }
  return $info;
}

/**
 * Actions callback.
 *
 * Cancel a membership.
 */
function membership_entity_cancel_action($membership, $context = array()) {
  $membership->status = MEMBERSHIP_ENTITY_CANCELLED;
}

/**
 * Actions callback.
 *
 * Bulk update membership pathauto aliases.
 */
function membership_entity_pathauto_update_action($membership, $context = array()) {
  membership_entity_update_alias($membership, 'bulkupdate', array('message' => TRUE));
}

/**
 * Implements hook_views_api().
 */
function membership_entity_views_api() {
  return array(
    'api' => 3,
    'path' => drupal_get_path('module', 'membership_entity') . '/views',
  );
}

/**
 * Convert a stdClass object to an instance of MembershipEntity.
 *
 * Shallow copies all properties of $object to a new
 * MembershipEntity instance.
 *
 * @param object $object
 *   The stdClass object to convert.
 *
 * @return MembershipEntity
 *   A new instance of MembershipEntity with all properties copied from $object.
 */
function membership_entity_create_from_stdclass($object) {
  $membership = membership_entity_create();
  foreach (get_object_vars($object) as $key => $value) {
    $membership->{$key} = $value;
  }
  return $membership;
}

/**
 * Create a new membership entity with default values.
 *
 * @param optioonal|array $values
 *   An associate array of default values for the membership.
 *
 * @return MembershipEntity
 *   The new (unsaved) membership object with default values.
 */
function membership_entity_create($values = array()) {
  return entity_create('membership_entity', $values);
}

/**
 * Load a single membership object.
 */
function membership_entity_load($mid = NULL, $reset = FALSE) {
  $memberships = membership_entity_load_multiple(array($mid), array(), $reset);
  return is_array($memberships) ? reset($memberships) : FALSE;
}

/**
 * Load a single membership object by member id.
 */
function membership_entity_load_by_member_id($member_id, $reset = FALSE) {
  $controller = entity_get_controller('membership_entity');
  if ($reset) {
    $controller->resetCache();
  }
  return $controller->loadByMemberID($member_id);
}

/**
 * Load all memberships for a given user.
 */
function membership_entity_load_by_user($account, $type = NULL, $reset = FALSE) {
  $controller = entity_get_controller('membership_entity');
  if ($reset) {
    $controller->resetCache();
  }
  return $controller->loadByUser($account, $type);
}

/**
 * Loads multiple membership objects.
 */
function membership_entity_load_multiple($mids = FALSE, $conditions = array(), $reset = FALSE) {
  return entity_load('membership_entity', $mids, $conditions, $reset);
}

/**
 * Implements hook_membership_entity_presave().
 */
function membership_entity_membership_entity_presave($membership) {
  // Generate a new member id for new memberships.
  if (!empty($membership->is_new) && empty($membership->member_id)) {
    $membership->member_id = membership_entity_next_member_id($membership);
  }
}

/**
 * Save a membership entity.
 *
 * @param MembershipEntity $membership
 *   MembershipEntity to save.
 */
function membership_entity_save(MembershipEntity &$membership) {
  return entity_save('membership_entity', $membership);
}

/**
 * Delete a membership entity.
 *
 * @param int $mid
 *   MembershipEntity ID to delete.
 */
function membership_entity_delete($mid) {
  membership_entity_delete_multiple(array($mid));
}

/**
 * Delete multiple membership entities.
 *
 * @param array $mids
 *   Array of MembershipEntity IDs to delete.
 */
function membership_entity_delete_multiple(array $mids) {
  entity_delete_multiple('membership_entity', $mids);
}

/**
 * Loads an entity revision.
 */
function membership_entity_revision_load($revision_id) {
  return entity_revision_load('membership_entity', $revision_id);
}

/**
 * Deletes an entity revision.
 */
function membership_entity_revision_delete($revision_id) {
  return entity_revision_delete('membership_entity', $revision_id);
}

/**
 * Checks whether the given entity is the default revision.
 */
function membership_entity_revision_is_default($entity) {
  return entity_revision_is_default('membership_entity', $entity);
}

/**
 * Sets a given entity revision as default revision.
 */
function membership_entity_revision_set_default($entity) {
  entity_revision_set_default('membership_entity', $entity);
}

/**
 * Private: Add/Remove roles managed by the membership.
 *
 * @param array $roles
 *   Key value array of roles keyed by role ID.
 */
function _membership_entity_update_roles(array $roles) {
  $accounts = user_load_multiple(array_keys($roles));

  foreach ($accounts as $uid => $account) {
    $rid = $roles[$uid]['rid'];
    if ($roles[$uid]['op'] == 'add' && !isset($account->roles[$rid])) {
      $account->roles[$rid] = $rid;
      user_save($account);
    }
    elseif ($roles[$uid]['op'] == 'remove' && isset($account->roles[$rid])) {
      unset($account->roles[$rid]);
      user_save($account);
    }
  }
}