<?php
// $Id: cmis_alfresco.utils.inc,v 1.3.2.1 2009-09-10 10:24:07 cbalan Exp $

/**
 * @file
 * Common Alfresco Related Utility Functions for Alfresco CMIS module
 *
 */

/**
 * Discoveries repository supported CMIS version 
 * 
 * @return repository CMIS version
 */
function _cmis_alfresco_utils_cmis_version_autodiscovery() {
  static $cmis_version;
  
  if (empty($cmis_version)) {
    $response = cmis_alfresco_invoke_service('/api/repository');
      
    foreach (array('0.5', '0.6') as $test_cmis_version) {
      $namespaces = cmis_alfresco_utils_get_namespaces($test_cmis_version);
      $xml = new SimpleXMLElement($response);
      $xml->registerXPathNamespace('cmis', $namespaces['cmis']);
        
      $cmis_object = $xml->workspace->children($namespaces['cmis']);
      $repository = $cmis_object->repositoryInfo;

      // Determine repository CMIS version
      foreach (array('cmisVersionSupported', 'cmisVersionsSupported') as $property_name) {
        if (isset($repository->$property_name)) {
          $cmis_version = (string)$repository->$property_name;
          return $cmis_version; 
        }
      }
    }

    throw new CMISException(t('Unable to auto-discovery supported CMIS version.'));
  }
  
  return $cmis_version; 
}

/**
 * Returns a list with known xml namespaces
 * 
 * @return array
 */
function cmis_alfresco_utils_get_namespaces($cmis_version = NULL) {
  $namespaces = array(
    'D' => 'http://www.w3.org/2005/Atom',
    'alf' => 'http://www.alfresco.org',
    'app' => 'http://www.w3.org/2007/app',
    'opensearch' => 'http://a9.com/-/spec/opensearch/1.1/',
    'relevance' => 'http://a9.com/-/opensearch/extensions/relevance/1.0/'
  );
  
  $cmis_version = empty($cmis_version)?_cmis_alfresco_utils_cmis_version_autodiscovery():$cmis_version; 
  if ($cmis_version >= '0.6') {
    $namespaces['cmis'] = 'http://docs.oasis-open.org/ns/cmis/core/200901';
  }
  else {
    $namespaces['cmis'] = 'http://www.cmis.org/2008/05';
  }
  
  return $namespaces;
}

/**
 * Shortcut for cmis_alfresco_utils_get_namespaces
 * 
 * @param $ns
 * @return string
 */
function cmis_alfresco_utils_ns($ns) {
  $namespaces = cmis_alfresco_utils_get_namespaces();
  return $namespaces[$ns];
}

/**
 * Returns a list of known property types
 * 
 */
function _cmis_alfresco_utils_known_property_types() {
  return array('Id', 'Boolean', 'String', 'Integer', 'DateTime');
}

/**
 * Process CMIS XML.
 * 
 * @param $xml CMIS response XML. 
 * @param $xpath xpath expression.
 */
function cmis_alfresco_utils_get_CMIS_xml($xml, $xpath = NULL) {
  try {
    $cmis_service = new SimpleXMLElement($xml);
  } 
  catch (Exception $e) {
    cmis_error_handler('cmis_alfresco_utils_get_CMIS_xml', $e);
    throw new CMISException(t('Unable to process xml.'));
  }

  foreach (cmis_alfresco_utils_get_namespaces() as $ns => $namespace) {
    $cmis_service->registerXPathNamespace($ns, $namespace);
  }
  
  if ($xpath) {
    return $cmis_service->xpath($xpath);
  }
  
  return $cmis_service;
}

/**
 * Resolves objectId from various formats.
 * 
 * Known formats:
 *  - url: http://localhost:8080/alfresco/service/api/path/workspace/SpacesStore/Company%20Home
 *  - path: Company Home/path to file
 *  - noderef: workspace://SpacesStore/91298612309871e
 *  - id: 91298612309871esdf
 *  
 * @todo Review objectId handling.
 *  
 * @param $objectId
 * @return array
 */
function cmis_alfresco_objectId($objectId) {
  // probably is already resolved ("instanceof" would have been more appropriate)
  if (is_array($objectId)) {
    return $objectId;
  }

  // unable to resolve node
  if (!is_string($objectId)) {
    return FALSE;
  }

  $parts = parse_url($objectId);

  if (substr($parts['scheme'], 0, 4) == 'http') {
    // @todo lookup id by path 
    $parts['url'] = $objectId;
    return $parts;
  }

  if (in_array($parts['scheme'], array ('workspace', 'archive', 'user', 'system', 'avm'))) {
    $parts['noderef'] = $objectId;
    $parts['noderef_url'] = $parts['scheme'] .'/'. $parts['host'] . $parts['path'];
    return $parts;
  }

  if ($parts['scheme'] == 'urn') {
    // Assuming that comes from workspace://SpacesStore/
    // @todo Review this assumption 
    $tmp_parts = parse_url($parts['path']);
    $parts['path'] = $tmp_parts['path'];

    $parts['noderef'] = 'workspace://SpacesStore/'. $parts['path'];
    $parts['scheme'] = 'workspace';
    $parts['host'] = 'SpacesStore';
    $parts['noderef_url'] = 'workspace/SpacesStore/'. $parts['path'];
    return $parts;
  }

  if ($parts['path'][0] == '/' && empty ($parts['scheme'])) {
    // Assuming that id looks like "/Company Home/path/to/object"
    if (substr($parts['path'], -1) == '/') {
      $parts['path'] = substr_replace($parts['path'], '', -1);
    }
    $response = cmis_alfresco_invoke_service('/api/path/workspace/SpacesStore'. $parts['path']);
    $object_info = cmis_alfresco_utils_get_CMIS_xml($response, '//D:entry');
    if (false != $object_info) {
      return cmis_alfresco_objectId((string) $object_info[0]->id);
    } 
    else {
      return FALSE;
    }
  }

  // unknown format
  watchdog('cmis_alfresco_objectId', 'Unable to resolve objectId: '. $objectId);
  return FALSE;
}

/**
 * Utility function for returning CMIS objects from cmis response(ie. getChildren, query, getDescendants)  
 * 
 * @param $entries
 * @return array
 */
function _cmis_alfresco_getEntries($entries) {
  $result = array();
  foreach ($entries as $entry) {
    $cmis_object = _cmis_alfresco_utils_entry($entry);    
    $cmis_object->properties = array();
    $cmis_element = $entry->children(cmis_alfresco_utils_ns('cmis'));
    foreach (_cmis_alfresco_utils_known_property_types() as $type) {
      $property_tag = 'property'. $type;
      foreach ($cmis_element->object->properties->$property_tag as $property) {
        $attrs = $property->attributes(cmis_alfresco_utils_ns('cmis'));
        $cmis_object->properties[(string) $attrs->name] = _cmis_alfresco_utils_cast($property->value, $type);
      }
    }
    
    $cmis_object->type = $cmis_object->properties['BaseType'];

    if ($cmis_object->type == 'document') {
      $cmis_object->size = $cmis_object->properties['ContentStreamLength'];
      $cmis_object->contentMimeType = $cmis_object->properties['ContentStreamMimeType'];
      $cmis_object->versionSeriesCheckedOutBy = $cmis_object->properties['VersionSeriesCheckedOutBy']; 
    }
    
    $result[] = $cmis_object;
  }

  return $result;
}

/**
 * Utility function for returning a common entry object from a feed entry 
 * 
 * @param $xml_element
 * @return stdClass 
 */
function _cmis_alfresco_utils_entry($xml_element) {
  $entry = new stdClass();
        
  $tmp_objectId = cmis_alfresco_objectId((string) $xml_element->id);
  $entry->id = $tmp_objectId['noderef'];
    
  $entry->title = (string) $xml_element->title;
  $entry->summary = (string) $xml_element->summary;
  $entry->updated = date_create($xml_element->updated);
  $entry->author = (string) $xml_element->author->name;

  return $entry;
}

/**
 * Utility function form casting cmis properties
 * 
 * @param $value
 * @param $type
 * @return mixed
 */
function _cmis_alfresco_utils_cast($value, $type) {
  $return = NULL;
  switch ($type) {
    case 'Integer':
      $return = (int) $value;
      break;
    case 'Boolean':
      $return = (bool) $value;
      break;
    case 'String':
    case 'Id':
      $return = (string) $value;
      break;
    case 'DateTime':
      $return = date_create((string) $value);
      break;
    default:
      $return = $value;
  }
  
  return $return;
}

/**
 * Utility function for encoding cmis properties
 * 
 * @param $propertyCollection
 * @return string
 */
function _cmis_alfresco_utils_properties_to_xml($propertyCollection = array()) {
  $properties_xml = '';
  
  foreach ($propertyCollection as $key => $value) {
    $property_type = gettype($value);

    switch ($property_type) {
      case 'integer':
      case 'boolean':
      case 'string':
        $properties_xml .= '<cmis:property'. ucfirst($property_type) .' cmis:name="'. $key .'">';
        $properties_xml .= '<cmis:value>'. $value .'</cmis:value>';
        $properties_xml .= '</cmis:property'. ucfirst($property_type) .'>';
        break;
      default:
        watchdog('_cmis_alfresco_utils_properties_to_xml', 'Unable to map property "@property" of type "@property_type" for destination object "@objectId"',
                array('@property' => $key, '@property_type' => $property_type, '@objectId' => $objectId), WATCHDOG_ERROR);

        drupal_set_message(t('Unable to map property "@property" of type "@property_type" for destination object "@objectId"', 
                            array('@property' => $key, '@property_type' => $property_type, '@objectId' => $objectId)), 'error');
    }
  }
  
  return $properties_xml;
}