subd.module

<?php

/**
 * Implementationation of hook_menu().
 */
function subd_menu() {
  $items = array();
  $items['subd-router'] = array(
    'page callback' => 'subd_router_page',
    'access arguments' => array('access content'),
    'type' => MENU_CALLBACK,
  );
  return $items;
}

function subd_router_page() {
  // If a node is found, swap in that node's content for the main page content.
  // This is not madness. THIS IS DRUPAL 7!
  if ($node = subd_get_current_node()) {
    drupal_set_breadcrumb(array());
    menu_set_active_item('node/' . $node->nid);
    return node_page_view($node);
  }
  else {
    // If there are no instances of the field defined, also bail out!
    $field = field_info_field('subd_subdomain');
    if (empty($field)) {
      return FALSE;
    }
    // Get a list of all subdomain'd nodes.
    $conditions = array(array('type', 'node'), array('value', 'NULL', '!='));
    $results = field_attach_query($field['id'], $conditions);

    if (!empty($results['node'])) {
      $base_uri = _subd_get_base_domain();
      foreach($results['node'] as $eid => $entity) {
        $node = node_load($eid);
        $subdomain = $node->subd_subdomain['und'][0]['value'];
        $items[] = l($node->title, "http://$subdomain.$base_uri");
        return theme('item_list', array('items' => $items));
      }
    }
  }
}

function subd_get_current_node() {
  // Sweet fuck, this is wrong and bad and wrong and more bad.
  // But, you know. How to extract the subdomain? Oh, Drupal. This works well
  // enough for a domain structure that is known and predictable.
  
  $uri = $_SERVER['HTTP_HOST'];
  $parsed = explode('.', $uri);
  if (count($parsed) > 2) {
    $subdomain = array_shift($parsed);
  }
  else {
    return FALSE;
  }

  // If there are no instances of the field defined, also bail out!
  $field = field_info_field('subd_subdomain');
  if (empty($field)) {
    return FALSE;
  }

  // See if any nodes match the subdomain.
  $conditions = array(array('type', 'node'), array('value', $subdomain, '='));
  $results = field_attach_query($field['id'], $conditions);

  if (!empty($results['node'])) {
    foreach($results['node'] as $eid => $entity) {
      return node_load($eid);
    }
  }
  
  return FALSE;
}

/**
 * Add a 'Subdomain' field to a given content type
 *
 * @param $type
 *  A node type object.
 * @param $label
 *  The label for the body instance.
 */
function subd_add_subdomain_field($type, $label = 'Subdomain') {
  // Add or remove the body field, as needed.
  $field = field_info_field('subd_subdomain');
  $instance = field_info_instance('node', 'subd_subdomain', $type);
  if (empty($field)) {
   $field = array(
    'field_name' => 'subd_subdomain',
    'type' => 'text',
    'entity_types' => array('node'),
    'translatable' => FALSE,
   );
   $field = field_create_field($field);
  }
  if (empty($instance)) {
   $instance = array(
    'field_name' => 'subd_subdomain',
    'entity_type' => 'node',
    'bundle' => $type,
    'label' => $label,
    'widget_type' => 'text',
    'settings' => array('required' => TRUE),

    // Define default formatters for the teaser and full view.
    'display' => array(
      'full' => array(
       'label' => 'hidden',
       'type' => 'hidden',
      ),
      'teaser' => array(
       'label' => 'hidden',
       'type' => 'hidden',
      ),
      'rss' => array(
       'label' => 'hidden',
       'type' => 'hidden',
      ),
      'search_index' => array(
       'label' => 'hidden',
       'type' => 'default',
      ),
      'search_results' => array(
       'label' => 'hidden',
       'type' => 'hidden',
      ),
    ),
   );
   field_create_instance($instance);
  }
}

function subd_preprocess_page(&$vars) {
  $vars['front_page'] = 'http://' . _subd_get_base_domain();
}

function _subd_get_base_domain() {
  $base_uri = $_SERVER['HTTP_HOST'];
  $parsed = explode('.', $base_uri);
  if (count($parsed) > 2) {
    array_shift($parsed);
    $base_uri = join('.', $parsed);
  }
  return $base_uri;
}