islandora_catalog_search.module

<?php

/**
 * @file
 * Module to add catalog search feature to citations
 */

/**
 * Page callback: Islandora catalog search settings
 *
 * @see islandora_catalog_search_menu()
 */
function islandora_catalog_search_form($form, &$form_state) {
  // checkbox options
  $form['islandora_catalog_search_options'] = array(
    '#type' => 'checkboxes',
    '#title' => t('Options'),
    '#options' => array(
      'new_window' => t('Open link in new window'),
      'use_image' => t('Use image for link'),
    ),
    '#default_value' => variable_get('islandora_catalog_search_options', ''),
  );

  // catalog url
  $form['islandora_catalog_search_url'] = array(
    '#type' => 'textfield',
    '#title' => t('Catalog URL'),
    '#default_value' => variable_get('islandora_catalog_search_url', ''),
    '#size' => 100,
    '#description' => t('The base URL to your catalog. Must start with "http://"'),
  );

  // http parameters
  $form['islandora_catalog_search_url_title'] = array(
    '#type' => 'textfield',
    '#title' => t('HTTP title parameter'),
    '#default_value' => variable_get('islandora_catalog_search_url_title', ''),
    '#size' => 100,
    '#description' => t('The HTTP parameter for article titles'),
  );
  $form['islandora_catalog_search_url_author'] = array(
    '#type' => 'textfield',
    '#title' => t('HTTP author parameter'),
    '#default_value' => variable_get('islandora_catalog_search_url_author', ''),
    '#size' => 100,
    '#description' => t('The HTTP parameter for article authors'),
  );
  $form['islandora_catalog_search_url_issn'] = array(
    '#type' => 'textfield',
    '#title' => t('HTTP issn parameter'),
    '#default_value' => variable_get('islandora_catalog_search_url_issn', ''),
    '#size' => 100,
    '#description' => t('The HTTP parameter for article ISSN'),
  );

  // extra parameters
  $form['islandora_catalog_search_url_extra'] = array(
    '#type' => 'textfield',
    '#title' => t('HTTP extra parameters'),
    '#default_value' => variable_get('islandora_catalog_search_url_extra', ''),
    '#size' => 100,
    '#maxlength' => 4096,
    '#description' => t('Extra HTTP parameters. Can have multiple of the form key=value separated by spaces'),
  );

  // upload image
  $form['islandora_catalog_search_link_image'] = array(
    '#type' => 'managed_file',
    '#name' => 'link_image',
    '#title' => t('Link Image'),
    '#default_value' => variable_get('islandora_catalog_search_link_image', ''),
    '#description' => t("Use this image as the link to your catalog"),
    '#upload_location' => 'public://catalog_link_image',
  );

  // image size
  $form['islandora_catalog_search_link_image_width'] = array(
    '#type' => 'textfield',
    '#title' => t('Image Width'),
    '#default_value' => variable_get('islandora_catalog_search_link_image_width', '150'),
    '#size' => 100,
    '#description' => t('The width of the link image'),
  );
  $form['islandora_catalog_search_link_image_height'] = array(
    '#type' => 'textfield',
    '#title' => t('Image Height'),
    '#default_value' => variable_get('islandora_catalog_search_link_image_height', '50'),
    '#size' => 100,
    '#description' => t('The height of the link image'),
  );

  // link text
  $form['islandora_catalog_search_link_text'] = array(
    '#type' => 'textfield',
    '#title' => t('Link Text'),
    '#default_value' => variable_get('islandora_catalog_search_link_text', 'Check our catalog'),
    '#size' => 100,
    '#description' => t('The Text to display for the link to the catalog if not using an image'),
  );

  // submit handler to save link image
  $form['#submit'][] = 'islandora_catalog_search_form_submit';

  return system_settings_form($form);
}


/*
 * Additional submit handler for making the link image file permanent
 */
function islandora_catalog_search_form_submit($form, &$form_state) {
  $file = $form['islandora_catalog_search_link_image']['#file'];
  if (is_object($file)) {
    $file->status = FILE_STATUS_PERMANENT;
    file_save($file);
    // prevent 'file not referenced' warning
    file_usage_add($file, 'islandora_catalog_link', 'node', 1);
  }
}


/**
 * Validate the size of the image specified in the admin form
 */
function islandora_catalog_search_form_validate($form, &$form_state) {
  $width = $form_state['values']['islandora_catalog_search_link_image_width'];
  $height = $form_state['values']['islandora_catalog_search_link_image_height'];

  if (!is_numeric($width)) {
    form_set_error('islandora_catalog_search_link_image_width', t('You must enter an integer for the image width.'));
  }

  elseif (!is_numeric($height)) {
    form_set_error('islandora_catalog_search_link_image_height', t('You must enter an integer for the image height.'));
  }

  elseif ($width <= 0) {
    form_set_error('islandora_catalog_search_link_image_width', t('Image width must be positive.'));
  }

  elseif ($height <= 0) {
    form_set_error('islandora_catalog_search_link_image_height', t('Image height must be positive.'));
  }
}


/**
 * Implements hook_menu().
 */
function islandora_catalog_search_menu() {
  $items = array();

  $items['admin/islandora/islandora_catalog_search'] = array(
    'title' => 'Islandora Catalog Search',
    'description' => 'Configuration for Islandora Catalog Search module',
    'page callback' => 'drupal_get_form',
    'page arguments' => array('islandora_catalog_search_form'),
    'access arguments' => array('manage islandora catalog search'),
    'type' => MENU_NORMAL_ITEM,
  );

  return $items;
}


/**
 * Implements hook_block_view().
 */
function islandora_catalog_search_block_view($delta = '') {
  switch ($delta) {
    case 'catalog_link':
      $block['subject'] = t('Link to a library catalog');
      $block['content'] = get_catalog_link();
      break;
  }
  return $block;
}


/**
 * Implements hook_block_info().
 */
function islandora_catalog_search_block_info() {
  // display a link to search the catalog
  $blocks['catalog_link'] = array(
    'info' => t('Link to library catalog'),
    'visibility' => BLOCK_VISIBILITY_LISTED,
    'pages' => 'islandora/object/citations*',
    'cache' => DRUPAL_NO_CACHE,
  );

  return $blocks;
}


/**
 * Create the catalog link.
 */
function get_catalog_link() {
  $options = variable_get('islandora_catalog_search_options', '');
  
  $link_options = array('external' => TRUE, 'absolute' => TRUE);
  if ($options['new_window'])
    $link_options['attributes'] = array('target' => '_blank');

  if ($options['use_image']) {
    $image_fid = variable_get('islandora_catalog_search_link_image');
    $image = file_load($image_fid);
    $image_url = file_create_url($image->uri);

    $width = variable_get('islandora_catalog_search_link_image_width', '150');
    $height = variable_get('islandora_catalog_search_link_image_height', '50');
    $title = variable_get('islandora_catalog_search_link_text', 'Check our catalog');

    $link_options['html'] = TRUE;
    $display = '<img title="' . $title . '" src="' . $image_url . '" style="height:' . $height . 'px; width:' . $width . 'px;"/>';
  }
  else {
    $display = variable_get('islandora_catalog_search_link_text', 'Check our catalog');
  }

  // build the URL
  $url = variable_get('islandora_catalog_search_url', '');
  // add the HTTP parameters
  add_params($link_options);

  return l($display, $url, $link_options);
}


/* 
 * Add the HTTP parameters to the URL
 * Code adapted from https://github.com/Islandora/islandora_scholar/blob/7.x/modules/islandora_google_scholar/islandora_google_scholar.module
 */
function add_params(&$link_options) {
  // get citation object
  $item = menu_get_item();
  $object = $item['map'][2];

  // get mods data if available 
  if (!isset($object['MODS']) || !islandora_datastream_access(ISLANDORA_VIEW_OBJECTS, $object['MODS']))
    return '';
  $mods = $object['MODS']->content;
  $mods_xml = new SimpleXMLElement($mods);
  $mods_xml->registerXPathNamespace('mods', 'http://www.loc.gov/mods/v3');

  $link_options['query'] = array();

  // get title
  $title_key = variable_get('islandora_catalog_search_url_title', '');
  $title_results = $mods_xml->xpath('//mods:mods[1]/mods:titleInfo/mods:title');
  $link_options['query'][$title_key] = (string) reset($title_results);

  // get first author
  $author_key = variable_get('islandora_catalog_search_url_author', '');
  $name_xml = $mods_xml->xpath('mods:name');
  if ($name_xml != null) {
    $name_xml = $name_xml[0];
    $name_parts = array();
    $name_xml->registerXPathNamespace('mods', 'http://www.loc.gov/mods/v3');
    $roles = $name_xml->xpath('mods:role/mods:roleTerm');
    $role = strtolower((string) reset($roles));
    if ($role) {
      if ($role == 'author') {
        foreach ($name_xml->xpath('mods:namePart') as $name_part) {
          if ((string) $name_part != '') {
            // Strip periods off the end.
            $np = (string) rtrim($name_part, '.');
            if ($name_part['type'] == 'given') {
            $name_parts['first_name'] = (string) $name_part;
            }
            if ($name_part['type'] == 'family') {
              $name_parts['last_name'] = $np;
            }
            if (!isset($name_part['type'])) {
              $name_parts['no_type'] = $np;
            }
          }
        }
      }
      if (isset($name_parts['last_name']) && isset($name_parts['first_name'])) {
        $link_options['query'][$author_key] = $name_parts['first_name'] . ' ' . $name_parts['last_name'];
      }
      elseif (isset($name_parts['no_type'])) {
        $link_options['query'][$author_key] = $name_parts['no_type'];
      }
    }
  }

  // get ISSN
  $issn_key = variable_get('islandora_catalog_search_url_issn', '');
  $issn = $mods_xml->xpath('//mods:identifier[@type="issn"]');
  if ($issn) {
    $link_options['query'][$issn_key] = str_replace(
      array("&", "=", ",", ";"),
      array('', '', '', ''),
      (string) reset($issn));
  }

  // add extras
  $extras = variable_get('islandora_catalog_search_url_extra', '');
  $arr = explode(" ", $extras);
  foreach ($arr as $extra) {
    $param = explode("=", $extra);
    if (count($param) != 2)
      continue;
    $link_options['query'][$param[0]] = $param[1];
  }
}


/**
 * Implements hook_permission
 */
function islandora_catalog_search_permission() {
  return array(
    'manage islandora catalog search' => array(
      'title' => t('Manage Islandora Catalog Search'),
      'description' => t('Perform admin tasks for the Islandora Catalog Search Module'),
    )
  );
}