islandora_openseadragon.module

<?php

/**
 * @file
 * Hooks and callbacks for this module.
 */

define('ISLANDORA_OPENSEADRAGON_REQUIRED_VERSION', '2.3.1');
define('ISLANDORA_OPENSEADRAGON_DEFAULT_TILE_SIZE', 256);
define('ISLANDORA_OPENSEADRAGON_DEFAULT_TILE_OVERLAP', 0);

/**
 * Implements hook_menu().
 */
function islandora_openseadragon_menu() {
  return array(
    'admin/islandora/islandora_viewers/openseadragon' => array(
      'title' => 'OpenSeadragon',
      'description' => 'Configure the OpenSeadragon viewer.',
      'page callback' => 'drupal_get_form',
      'access arguments' => array('administer site configuration'),
      'page arguments' => array('islandora_openseadragon_admin'),
      'file' => 'includes/admin.form.inc',
      'type' => MENU_NORMAL_ITEM,
    ),
    'islandora/object/%islandora_object/download_clip' => array(
      'page callback' => 'islandora_openseadragon_download_clip',
      'page arguments' => array(2),
      'type' => MENU_CALLBACK,
      'access callback' => 'islandora_object_access',
      'access arguments' => array(ISLANDORA_VIEW_OBJECTS, 2),
      'file' => 'includes/download.clip.inc',
      'load arguments' => array(2),
    ),
  );
}

/**
 * Implements hook_theme().
 */
function islandora_openseadragon_theme() {
  return array(
    'islandora_openseadragon_viewer' => array(
      'variables' => array(
        // @deprecated (7.x-1.10):
        // 'uri' and 'fedora_object' has been replaced by the use of 'pid' and
        // 'tile_sources'.
        'uri' => '',
        'fedora_object' => NULL,
        'pid' => NULL,
        'tile_sources' => array(),
      ),
      'file' => 'theme/theme.inc',
      'template' => 'theme/islandora-openseadragon',
    ),
    // A link for clipping JP2 datastreams via djatoka.
    'islandora_openseadragon_clipper' => array(
      'file' => 'theme/theme.inc',
      'variables' => array(
        'pid' => NULL,
      ),
    ),
  );
}

/**
 * Implements hook_islandora_viewer_info().
 */
function islandora_openseadragon_islandora_viewer_info() {
  return array(
    // @XXX The element returned has a width:100% but no natural flow width; it
    // is completely dependent on it's parent.
    'islandora_openseadragon' => array(
      'label' => t('OpenSeadragon'),
      // Later we'll add DZI too.
      'description' => t('OpenSeadragon viewer with djatoka as tilesource.'),
      'configuration' => 'admin/islandora/islandora_viewers/openseadragon',
      'callback' => 'islandora_openseadragon_callback',
      // DZI has xml as mimetype? Not sure how to handle that.
      'mimetype' => array('image/jp2'),
    ),
  );
}

/**
 * Callback function for the viewer.
 *
 * @param array $params
 *   Params required by the theme. We require the keys:
 *   - pid: The PID of the object.
 *   - dsid: This DSID being displayed.
 *   - token: The token we are working with.
 * @param AbstractObject $object
 *   The object that we are viewing.
 *
 * @return string
 *   HTML representation of the OpenSeadragon viewer
 */
function islandora_openseadragon_callback(array $params = array(), AbstractObject $object = NULL) {
  module_load_include('inc', 'islandora_openseadragon', 'includes/utilities');

  if (isset($params['jp2_url']) && !(isset($params['pid']) && isset($params['dsid']) && isset($params['token']))) {
    $message = islandora_deprecated('7.x-1.11', t('The jp2_url parameter has been depreciated. Please update your code before the next release.'));
    trigger_error(filter_xss($message), E_USER_DEPRECATED);

    // Try to mangle the jp2_url into the data we need.
    $matches = array();
    preg_match('/object\/([^\/]*)\/datastream\/([^\/]*).*token=([^&]*)/', $params['jp2_url'], $matches);
    $pid = isset($matches[1]) ? $matches[1] : NULL;
    $dsid = isset($matches[2]) ? $matches[2] : NULL;
    $token = isset($matches[3]) ? $matches[3] : NULL;

    if (!isset($params['pid'])) {
      $params['pid'] = urldecode($pid);
    }
    if (!isset($params['dsid'])) {
      $params['dsid'] = urldecode($dsid);
    }
    if (!isset($params['token'])) {
      $params['token'] = urldecode($token);
    }
  }

  if (isset($params['pid']) && isset($params['dsid']) && isset($params['token'])) {
    $token_header = variable_get('islandora_openseadragon_tilesource', 'djatoka') == 'iiif'
      && variable_get('islandora_openseadragon_iiif_token_header', FALSE);

    return theme('islandora_openseadragon_viewer', array(
      'pid' => $params['pid'],
      'tile_sources' => islandora_openseadragon_tile_source($params['pid'], $params['dsid'], $params['token']),
      'token' => $params['token'],
      'token_header' => $token_header,
    ));
  }
}

/**
 * Implements hook_process_theme().
 */
function islandora_openseadragon_preprocess_islandora_object_print(array &$variables) {
  if (isset($_GET['clip'])) {
    module_load_include('inc', 'islandora_openseadragon', 'includes/utilities');
    $clip_parts = islandora_openseadragon_construct_clip_url($_GET['clip']);
    if ($clip_parts) {
      $variables['clip'] = $clip_parts['original_params'];
      $variables['content']['clip'] = array(
        '#weight' => 0,
        '#prefix' => "<div id='clip'>",
        '#markup' => theme_image(array(
          'path' => $clip_parts['image_url'],
          'attributes' => $clip_parts['dimensions'],
        )),
        '#suffix' => '</div>',
      );
    }
    else {
      drupal_set_message(t('Invalid clip parameters passed.'), 'error');
    }
  }
}

/**
 * Implements hook_token_info().
 */
function islandora_openseadragon_token_info() {
  $info = array();

  $info['types']['islandora_openseadragon'] = array(
    'name' => t('Islandora Openseadragon'),
    'description' => t('Tokens for building IIIF identifer in Islandora Openseadragon.'),
    'needs-data' => 'islandora_openseadragon',
  );

  $info['tokens']['islandora_openseadragon']['pid'] = array(
    'name' => t('PID'),
    'description' => t('The objects PID.'),
  );

  $info['tokens']['islandora_openseadragon']['dsid'] = array(
    'name' => t('DSID'),
    'description' => t('The objects DSID.'),
  );

  $info['tokens']['islandora_openseadragon']['url'] = array(
    'name' => t('URL'),
    'description' => t('The URL to the object in Islandora.'),
  );

  $info['tokens']['islandora_openseadragon']['url_token'] = array(
    'name' => t('URL with Token'),
    'description' => t('The URL to the object in Islandora with token in the query string.'),
  );

  $info['tokens']['islandora_openseadragon']['token'] = array(
    'name' => t('Token'),
    'description' => t('The token that can be used to access the object in Islandora.'),
  );

  return $info;
}

/**
 * Implements hook_tokens().
 */
function islandora_openseadragon_tokens($type, $tokens, array $data = array(), array $options = array()) {
  $replacements = array();

  if ($type != 'islandora_openseadragon' || !isset($data['islandora_openseadragon'])) {
    return $replacements;
  }

  $pid = $data['islandora_openseadragon']['pid'];
  $dsid = $data['islandora_openseadragon']['dsid'];
  $token = $data['islandora_openseadragon']['token'];

  foreach ($tokens as $name => $original) {
    if ($name == 'pid') {
      $replacements[$original] = $pid;
    }
    elseif ($name == 'dsid') {
      $replacements[$original] = $dsid;
    }
    elseif ($name == 'token') {
      $replacements[$original] = $token;
    }
    elseif ($name == 'url' || $name == 'url_token') {
      $options = array(
        'absolute' => TRUE,
        'language' => language_default(),
        'https' => (function_exists('drupal_is_https') ?
          drupal_is_https() :
          (isset($_SERVER['HTTPS']) && strtolower($_SERVER['HTTPS']) == 'on')
        ),
      );

      if ($name == 'url_token') {
        $options['query'] = array(
          'token' => $token,
        );
      }

      $replacements[$original] = url("islandora/object/{$pid}/datastream/{$dsid}/view", $options);
    }
  }

  return $replacements;
}