Registrations Requiring Payment Should Be Programmatically Set to Pending Status

I have a semi-unique need, and a packaged solution I thought the authors might want to handle.

I have events that are both paid, and free. If I've understood how this module works, it just doesn't quite cut it. There's a default registration state option, which in my case needs to be set to completed for anonymous users' free registrations. But there's a separate workflow for users purchasing paid registrations. They need to pay before we can complete it. Right now, I didn't find a way to automatically change payment required events (defined by a price greater than 0 and registrations enabled) to mark them as pending. Exposing the form item state for them to set it as pending themselves is not going to work. I developed the following code that makes it work instead:

Custom.module

This file is used primarly as a routing file to custom/registration/registration.module.inc where logic stored.

/**
 * Modifies the submit actions of the commerce form registration
 * to change the registration's default state to pending if payment is required
 * @see registration_commerce_form_registration_form_alter
 */
function custom_form_registration_form_alter(&$form, &$form_state){
  module_load_include('module.inc', 'custom', 'registration/registration');
  _custom_registration_form_registration_form_alter($form, $form_state);
}

/**
 * Modifies the registration state for payment required registrations to pending
 */
function custom_form_registration_form_alter_validate(&$form, &$form_state){
  module_load_include('module.inc', 'custom', 'registration/registration');
  _custom_registration_form_registration_form_alter_validate($form, $form_state);
}

/**
 * Provides a payment required message for pending registrations
 */
function custom_form_registration_form_alter_submit(&$form, &$form_state){
  module_load_include('module.inc', 'custom', 'registration/registration');
  _custom_registration_form_registration_form_alter_submit($form, $form_state);
}

registration.module.inc

/**
 * Modifies the submit actions of the commerce form registration
 * to change the registration's default state to pending if payment is required
 * @see registration_commerce_form_registration_form_alter
 */
function _custom_registration_form_registration_form_alter(&$form, &$form_state){
  $reg_type = registration_type_load($form['#bundle']);
  $reg_settings = $reg_type->registration_commerce_settings;
  if ($reg_settings['enable']) {
    // Add our custom handlers
    $form['#validate'][] = 'custom_form_registration_form_alter_validate';
    $form['#submit'][] = 'custom_form_registration_form_alter_submit';
  }
}

/**
 * Basic validation hook for registrations
 *   This will change the state of the registration to pending if payment is required
 */
function _custom_registration_form_registration_form_alter_validate(&$form, &$form_state){
  $reg_type = registration_type_load($form['#bundle']);
  $reg_settings = $reg_type->registration_commerce_settings;
  if ($reg_settings['enable']) {
    // Pull the registration specific details to check the price
    // This is a bit of custom. You could check $reg_settings['default_price']['amount'] instead
    $entity = $form['#entity'];
    $entity_settings = registration_entity_settings($entity->entity_type, $entity->entity_id);
    // Since registration is enabled, if a price exists, force the status back to pending
    if( !empty($entity_settings['settings']['price']['amount']) ){
      $form_state['values']['state'] = 'pending';
    }
  }
}

/**
 * Provides a payment required message for pending registrations
 */
function _custom_registration_form_registration_form_alter_submit(&$form, &$form_state){
  if( $form_state['values']['state'] == 'pending' ){
    drupal_set_message( t('Please submit payment now to complete your pending registration.') );
  }
}