<?php
// $Id: xmlrpc_server.module,v 1.8 2010-12-10 03:12:35 ocyrus Exp $
/**
 * @file
 *  Enable XML-RPC for services module.
 *
 * Most of the work here is converting the REST-style resource definitions
 * to XMLRPC-style procedure calls. These procedures are renamed as 
 * <resource>.<method>. So the node resource's retrieve method has an XMLRPC
 * procedure name of node.retrieve. Actions prepend 'action_' to the procedure
 * name. So the login action of the user resource becomes user.action_login. 
 */

/**
 * Implementation of hook_server_info().
 */
function xmlrpc_server_server_info() {
  return array(
    'name' => 'XMLRPC',
  );
}

/**
 * Implementation of hook_server().
 */
function xmlrpc_server_server() {
  require_once './includes/xmlrpc.inc';
  require_once './includes/xmlrpcs.inc';

  // 
  return xmlrpc_server(xmlrpc_server_xmlrpc());
}

/**
 * Return an array of all defined services methods and callbacks.
 *
 * @see xmlrpc_server()
 */
function xmlrpc_server_xmlrpc() {
  $callbacks = array();
  
  $resources = services_get_resources();
  if (!empty($resources)) {
    // Translate all resources
    foreach ($resources as $name => $def) {
      foreach (_xmlrpc_server_resources_as_procedures($def) as $method) {
        $callbacks[$method['method']] = 'xmlrpc_server_call_wrapper';
      }
    }
  }

  return $callbacks;
}

/**
 * Pass XMLRPC server requests to the appropriate services method.
 *
 * This function can take varying parameters as are appropriate to
 * the service in question. 
 */
function xmlrpc_server_call_wrapper() {
  $xmlrpc_server = xmlrpc_server_get();
  $method_name = $xmlrpc_server->message->methodname;
  $args = func_get_args();
  $endpoint = services_get_server_info('endpoint', '');
  $controller = services_controller_get($method_name, $endpoint);

  try {
    return services_controller_execute($controller, $args);  
  } 
  catch (Exception $e) {
    $code = $e->getCode();
    switch($code) {
      case 401:
        drupal_set_header('HTTP/1.0 401 Unauthorized: ' . $e->getMessage());
      break;
      case 404:
        drupal_set_header('HTTP/1.0 404 Not found: ' . $e->getMessage());
      break;
      case 406:
        drupal_set_header('HTTP/1.0 406 Not Acceptable: ' . $e->getMessage());
      break;
      default:
        if ($code >= 400 && $code < 600) {
          drupal_set_header('HTTP/1.0 ' . $code . ' ' . $e->getMessage());
        }
        else {
          drupal_set_header('HTTP/1.0 500 An error occurred: (' . $code . ') ' . $e->getMessage());
        }
      break;
    }
  }
}

/**
 * Convert a resource to XMLRPC-style methods.
 *
 * @param array $resource
 *   A resource definition.
 *
 * @return array
 *   An array of XMLRPC method definitions
 */
function _xmlrpc_server_resources_as_procedures($resource) {
  static $controllers = array(
    'create' => 'create',
    'delete' => 'delete',
    'retrieve' => 'retrieve',
    'update' => 'update',
    'index' => 'index',
  ), $subcontrollers = array(
    'relationships' => 'related',
    'targeted actions' => 'targeted_action',
  );

  $methods = array();

  foreach ($controllers as $attr => $name) {
    if (isset($resource[$attr])) {
      $methods[] = _xmlrpc_server_resource_controller_as_procedure($resource['name'], $name, $resource[$attr]);
    }
  }

  foreach ($subcontrollers as $attr => $name) {
    if (isset($resource[$attr])) {
      foreach ($resource[$attr] as $sc_name => $controller) {
        $methods[] = _xmlrpc_server_resource_controller_as_procedure($resource['name'], $name .'_'. $sc_name, $controller);
      }
    }
  }

  if (isset($resource['actions'])) {
    foreach ($resource['actions'] as $sc_name => $controller) {
      $methods[] = _xmlrpc_server_resource_controller_as_procedure($resource['name'], 'action_'. $sc_name, $controller);
    }
  }

  return $methods;
}

/**
 * Helper function for _xmlrpc_server_resources_as_procedures() that turns a resource
 * controller into an XMLRPC method.
 *
 * @param $resource
 *   The resource being converted (node, user, etc.)
 * @param $name
 *   The method name (retrieve, create, etc.)
 * @param $controller
 *   Associative array defining the method's properties and callbacks.
 *
 */
function _xmlrpc_server_resource_controller_as_procedure($resource, $name, $controller) {
  $method = array_merge($controller, array(
    'method' => $resource .'.'. $name,
  ));

  return $method;
}