<?php 

function noderefcreate_widget_info() {
  return array(
    'noderefcreate_autocomplete' => array(
      'label' => t('Autocomplete text field with create'),
      'field types' => array('nodereference'),
      'multiple values' => CONTENT_HANDLE_CORE,
      'callbacks' => array(
        'default value' => CONTENT_CALLBACK_DEFAULT,
      ),
    ),
  );
}


function noderefcreate_widget_settings($op, $widget) {
  switch ($op) {
    case 'form':
      $form = array();
      $match = isset($widget['autocomplete_match']) ? $widget['autocomplete_match'] : 'contains';
      if ($widget['type'] == 'noderefcreate_autocomplete') {
        $form['autocomplete_match'] = array(
          '#type' => 'select',
          '#title' => t('Autocomplete matching'),
          '#default_value' => $match,
          '#options' => array(
            'starts_with' => t('Starts with'),
            'contains' => t('Contains'),
          ),
          '#description' => t('Select the method used to collect autocomplete suggestions. Note that <em>Contains</em> can cause performance issues on sites with thousands of nodes.'),
        );
      }
      else {
        $form['autocomplete_match'] = array('#type' => 'hidden', '#value' => $match);
      }
      return $form;

    case 'save':
      return array('autocomplete_match');
  }
}

function noderefcreate_widget(&$form, &$form_state, $field, $items, $delta = 0) {
  switch ($field['widget']['type']) {
    case 'noderefcreate_autocomplete':
      $element = array(
        '#type' => 'nodereference_autocomplete',
        '#default_value' => isset($items[$delta]) ? $items[$delta] : NULL,
        '#value_callback' => 'nodereference_autocomplete_value',
      	'#process' => array('noderefcreate_autocomplete_process'),
      );
      break;
  }
  return $element;
}


function noderefcreate_autocomplete_process($element, $edit, $form_state, $form) {

  // The nodereference autocomplete widget doesn't need to create its own
  // element, it can wrap around the text_textfield element and add an autocomplete
  // path and some extra processing to it.
  // Add a validation step where the value can be unwrapped.
  $field_key  = $element['#columns'][0];

  $element[$field_key] = array(
    '#type' => 'text_textfield',
    '#default_value' => isset($element['#value']) ? $element['#value'] : '',
    '#autocomplete_path' => 'nodereference/autocomplete/'. $element['#field_name'],
    // The following values were set by the content module and need
    // to be passed down to the nested element.
    '#title' => $element['#title'],
    '#required' => $element['#required'],
    '#description' => $element['#description'],
    '#field_name' => $element['#field_name'],
    '#type_name' => $element['#type_name'],
    '#delta' => $element['#delta'],
    '#columns' => $element['#columns'],
  );
  if (empty($element[$field_key]['#element_validate'])) {
    $element[$field_key]['#element_validate'] = array();
  }
  array_unshift($element[$field_key]['#element_validate'], 'noderefcreate_autocomplete_validate');

  // Used so that hook_field('validate') knows where to flag an error.
  $element['_error_element'] = array(
    '#type' => 'value',
    // Wrapping the element around a text_textfield element creates a
    // nested element, so the final id will look like 'field-name-0-nid-nid'.
    '#value' => implode('][', array_merge($element['#parents'], array($field_key, $field_key))),
  );
  return $element;
}


function noderefcreate_autocomplete_validate($element, &$form_state) {
  $field_name = $element['#field_name'];
  $type_name = $element['#type_name'];
  $field = content_fields($field_name, $type_name);
  $field_key  = $element['#columns'][0];
  $delta = $element['#delta'];
  $value = $element['#value'][$field_key];
  $nid = NULL;
  if (!empty($value)) {
    preg_match('/^(?:\s*|(.*) )?\[\s*nid\s*:\s*(\d+)\s*\]$/', $value, $matches);
    if (!empty($matches)) {
      // Explicit [nid:n].
      list(, $title, $nid) = $matches;
      if (!empty($title) && ($n = node_load($nid)) && $title != $n->title) {
        form_error($element[$field_key], t('%name: title mismatch. Please check your selection.', array('%name' => t($field['widget']['label']))));
      }
    }
    else {
      // No explicit nid.
      $reference = _nodereference_potential_references($field, $value, 'equals', NULL, 1);
      if (empty($reference)) {
        $newnode = NULL;
        if (is_array($field['referenceable_types'])) {
          foreach (array_filter($field['referenceable_types']) as $related_type) {
            $newnode->type = $related_type;
          }
        }
        global $user;
        $newnode->uid = $user->uid;
        $newnode->title = $value;
        node_save($newnode);
        $nid = $newnode->nid;
      }
      else {
        // TODO:
        // the best thing would be to present the user with an additional form,
        // allowing the user to choose between valid candidates with the same title
        // ATM, we pick the first matching candidate...
        $nid = key($reference);
      }
    }
  }
  form_set_value($element, $nid, $form_state);
}