citation_exporter_extra.module

<?php

/**
 * Implements hook_init().
 */
function  citation_exporter_extra_init() {
  // Load block definition
  module_load_include('inc', 'citation_exporter_extra', 'includes/blocks/export.block');
}

/**
 * Implements hook_help().
 */
function citation_exporter_extra_help($path, $arg) {
  switch ($path) {
    case 'admin/help#citation_exporter_extra':
      return '<p>' .   t('Enables stream downloads from object data streams thought the use of bibutils and easyrdf')  . '</p>';
      break;
    default;
  }
}

/**
 *  Implements hook_mods_download_format_alter
 * @param $formats
 * @return array
 */
function citation_exporter_extra_mods_download_format_alter(&$formats) {
  $formats = array_merge($formats, array(
    'BibTex' => array(
      'url' => 'islandora/object/[fedora:pid]/download_mods_as_bibtext',
      'title' => "Compatible with Zotero"
    ),
    'EndNote' => array(
      'url' => 'islandora/object/[fedora:pid]/download_mods_as_endnote',
      'title' => "Compatible with EndNote"
    ),
    'MARC' => array(
      'url' => 'islandora/object/[fedora:pid]/download_mods_as_marc'
    ),
    'MARCXML' => array(
      'url' => 'islandora/object/[fedora:pid]/download_mods_as_marcxml',
      'title' => 'Compatible with XML viewers'
    ),
    'DublinCore' => array(
      'url' => 'islandora/object/[fedora:pid]/datastream/DC/download',
      'title' => 'Compatible with XML viewers'
    ),
    'RIS' => array(
      'url' => 'islandora/object/[fedora:pid]/download_mods_as_ris',
      'title' => "Compatible with EndNote, Refworks, Zotero, and Reference Manager"
    ),
    //'JSON',
    'JSON' => array(
      'url' => 'islandora/object/[fedora:pid]/download_mods_as_json',
      'title' => 'Compatible with Zotero'
    ),
  ));

  return $formats;
}

/**
 * @param IslandoraFedoraObject|bool $object
 *
 * @return array|bool
 */
function citation_exporter_extra_get_export_formats($object = FALSE) {

  $format_links = array();
  $formats = array();

  $enabled_options = variable_get('islandora_export_formats_available_options', []);
  // Pull download formats from other modules whereas possible
  drupal_alter('mods_download_format', $formats);
  // If this is an object, a fedora Object
  if (is_object($object) && $object instanceof FedoraObject) {
    foreach ($formats as $format => $value) {
      if (isset($enabled_options[$format]) && !empty($enabled_options[$format])) {
        $format_links[] = l($format, url(token_replace($value['url'], array('fedora' => $object))), array(
          'attributes' => array (
            'title' => (isset($value['title'])) ? $value['title'] : ''
          )
        ));
      }
    }
    return $format_links;
  }
  return $formats;
}

/**
 * Implements hook_menu().
 */
function citation_exporter_extra_menu() {
  return array(
    'islandora/object/%islandora_object/download_mods_as_marc' => array(
      'title' => 'Download MARC',
      'type' => MENU_CALLBACK,
      'page callback' => 'citation_exporter_extra_xml_download_mods_to_marc',
      'page arguments' => array(2),
      'delivery callback' => 'citation_exporter_extra_download',
      'access callback' => 'citation_exporter_extra_access_callback',
      'access arguments' => array(2)
    ),
    'islandora/object/%islandora_object/download_mods_as_endnote' => array(
      'title' => 'Download EndNoteXml',
      'type' => MENU_CALLBACK,
      'page callback' => 'citation_exporter_extra_xml_download_mods_to_format',
      'page arguments' => array(2, 'MODS', 'EndNote'),
      'delivery callback' => 'citation_exporter_extra_download',
      'access callback' => 'citation_exporter_extra_access_callback',
      'access arguments' => array(2)
    ),

    'islandora/object/%islandora_object/download_mods_as_bibtext' => array(
      'title' => 'Download BibText',
      'type' => MENU_CALLBACK,
      'page callback' => 'citation_exporter_extra_xml_download_mods_to_format',
      'page arguments' => array(2, 'MODS', 'BibTeX'),
      'delivery callback' => 'citation_exporter_extra_download',
      'access callback' => 'citation_exporter_extra_access_callback',
      'access arguments' => array(2)
    ),
    'islandora/object/%islandora_object/download_mods_as_ris' => array(
      'title' => 'Download RIS',
      'type' => MENU_CALLBACK,
      'page callback' => 'citation_exporter_extra_xml_download_mods_to_format',
      'page arguments' => array(2, 'MODS', 'RIS'),
      'delivery callback' => 'citation_exporter_extra_download',
      'access callback' => 'citation_exporter_extra_access_callback',
      'access arguments' => array(2)
    ),
    'islandora/object/%islandora_object/download_mods_as_json' => array(
      'title' => 'Download JSON',
      'type' => MENU_CALLBACK,
      'page callback' => 'citation_exporter_extra_xml_download_mods_to_json',
      'page arguments' => array(2),
      'delivery callback' => 'citation_exporter_extra_download',
      'access callback' => 'citation_exporter_extra_access_callback',
      'access arguments' => array(2)
    ),
  );
}

/**
 * Prepares  a fedora object with a MODS stream to JSON
 *
 * @param \FedoraObject $object
 *
 * @return string
 */
function citation_exporter_extra_xml_download_mods_to_json($object) {
  module_load_include('inc', 'citeproc', 'includes/converter');
  $ds = $object->getDatastream('MODS');
  $raw = convert_mods_to_citeproc_jsons($ds->content);
  if ($raw) {
    $raw_json = json_encode($raw);
    if ($raw_json) {
      return $raw_json;
    }
  }
  drupal_not_found();
}
/**
 * Access callback.
 *
 * Requires that the given object contains a MODS datastream (and to be
 * viewable, as per the stock permissions).
 *
 * @param AbstractObject $object
 *   The object to test, if NULL the given object doesn't exist or is
 *   inaccessible.
 *
 * @return bool
 *   TRUE if the user is allowed to access the object, FALSE
 *   otherwise.
 */
function citation_exporter_extra_access_callback($object) {
  return is_object($object) && isset($object['MODS']) && islandora_datastream_access(ISLANDORA_VIEW_OBJECTS, $object['MODS']);
}

/**
 *
 * Converts an object MODS datastream to marcXML for download
 *
 * @param $object \FedoraObject
 *
 * @return string
 */
function citation_exporter_extra_xml_download_mods_to_marc($object) {
  $base_module = 'islandora_marcxml';
  $marc = function() use ($base_module, $object) {
    module_load_include('inc', $base_module, 'includes/utilities');
    return islandora_marcxml_transform_marc_to_html($object);
  };
  if (citation_exporter_extra_access_callback($object)) {
    if (!module_exists($base_module)) {
      // MarcXML is NOT enabled, try to enable it
      if (module_enable(array($base_module))) {
        $ob = $marc();
        module_disable(array($base_module));
        return $ob;
      } else {
        // We can't enable the module, abort
      }
    } else {
      // Module already enabled
      return $marc();
    }
  } else {
    drupal_access_denied();
  }
}

/**
 *
 * Downloads a MODS datastream into the $to format, and returns a file in the
 * system
 *
 * @param \FedoraObject $object
 *
 * @param $from
 * @param $to
 *
 * @return false|string|void
 */
function citation_exporter_extra_xml_download_mods_to_format($object, $from, $to) {
  module_load_include('inc', 'citation_exporter_extra', 'includes/utilities');

    /**
   * @var \IslandoraFedoraDatastream $ds
   */
    $ds = $object->getDatastream('MODS');
    // Set unique name to  avoid errors when downloading several files from the same object
    $t_name = time();
    $enxml_file = file_save_data($ds->content, "temporary://temp_en_{$t_name}_{$object->id}");
    $enxml_file->status &= ~FILE_STATUS_PERMANENT;
    file_save($enxml_file);
    $mods_file = drupal_tempnam('temporary://', "temp_mods_{$t_name}_{$object->id}");

    $res = BibutilsExtra::Convert(
      drupal_realpath($enxml_file->uri),
      $from,
      drupal_realpath($mods_file),
      $to
    );

    if ($res) {
      $to_return = file_get_contents($mods_file);
      $f_path = $enxml_file->uri;
      file_unmanaged_delete($f_path);
      file_unmanaged_delete($mods_file);
      return $to_return;
    }
    else {
      drupal_not_found();
    }
}

/**
 * Delivery callback used to download the output as XML.
 *
 * @param string $output
 *   The content to download.
 */
function citation_exporter_extra_download($output) {
  $key = arg(3);
  $object = arg(2);
  $name = 'export';
  // If this object has a valid label let's use it to generate our download file
  if ($object) {
    $fedora_object = islandora_object_load($object);
    $name = $fedora_object->label;
  }
  drupal_add_http_header('Content-length', strlen($output));
  drupal_add_http_header('Content-type', 'text/plain;charset=utf8');
  switch ($key) {
    case 'download_mods_as_marc':
      drupal_add_http_header('Content-Disposition', "attachment; filename=\"{$name}.marc\"");
      break;
    case 'download_mods_as_bibtext':
    case 'download_mods_as_format':
      drupal_add_http_header('Content-Disposition', "attachment; filename=\"{$name}.bib\"");
      break;
    case 'download_mods_as_endnote':
      drupal_add_http_header('Content-Disposition', "attachment; filename=\"{$name}.end\"");
      break;
    case 'download_mods_as_ris':
      drupal_add_http_header('Content-Disposition', "attachment; filename=\"{$name}.ris\"");
      break;
    case 'download_mods_as_json':
      drupal_add_http_header('Content-Disposition', "attachment; filename=\"{$name}.json\"");
      break;
    default:
      drupal_add_http_header('Content-Disposition', "attachment; filename=\"{$name}.export\"");
  }

  print $output;
  drupal_page_footer();
}

/**
 * Implements hook_theme().
 */
function citation_exporter_extra_theme($existing, $type, $theme, $path) {
  return array(
    'islandora_export_available_formats' => array(
      'template' => 'object--export_available_formats',
      //'function' => 'theme_islandora_export_available_formats',
      'path' => drupal_get_path('module', 'citation_exporter_extra') . '/templates',
      'variables' => array (
        'object' => NULL,
        'formats' => citation_exporter_extra_get_export_formats()
      )
    )
  );
}

/**
 * Generates the HTML that will be used with the block
 * Implements hook preprocess_islandora_export_available_formats
 * @param $variables
 */
function citation_exporter_extra_preprocess_islandora_export_available_formats(&$variables) {
  //$generate a list of potential new values!
  $variables['available_formats'] = theme_item_list([
    'items' => citation_exporter_extra_get_export_formats($variables['object']),
    'title' => t('Downloadable format'),
    'type' => 'ul',
    'attributes' => [],
  ]);
}