iiif_image_field.module

<?php 

/**
 *  Provides a simple field for easily embedding images from IIIF Image Servers (currently supports Image API 2.0 only, with plans to support previous versions)
 *
 *  This module is not intended to replace media - it does not allow for any local storage of images, custom players or anything else
 *  It simply allows users to embed images from IIIF Image Servers - and provides a hook to allow other modules to provide more providers.
 *
 *  @author shaune
 */
/**
 *  Implementation of hook_menu
 *  create out admin page
 */
 function iiif_image_field_menu(){
   return array(
     'admin/config/media/iiif_image_field' => array(
       'title' => 'IIIF Images',
       'description' => 'Configuration form for the IIIF Image Field, allows one to set viewer options.',
       'page callback' => 'drupal_get_form',
       'page arguments' => array('iiif_image_field_get_form'),
       'access arguments' => array('administer site configuration'),
       'type' => MENU_NORMAL_ITEM,
     )
   );
 }

/**
 * Page callback: IIIF Image Field Admin settings
 *
 * @see iiif_image_field_menu()
 */
function iiif_image_field_get_form($form, &$form_state) {
  $form['image_server_base'] = array(
    '#type' => 'textfield',
    '#title' => t('Base URL of IIIF Image Server'),
    '#default_value' => variable_get('image_server_base', ''),
    '#size' => 255,
    '#maxlength' => 512,
    '#description' => t('This is the combination of host server and prefix (path) to the service. No trailing slash.'),
    '#required' => TRUE,
  );
  $form['image_api_version'] = array(
    '#type' => 'select',
    '#options' => array(
        '1.1' => t('1.1'),
        '2.0' => t('2.0')
      ),
    '#title' => t('Image API Version'),
    '#default_value' => variable_get('image_api_version', '1.1'),
    '#description' => t('Set this to the highest Image API Version your image server supports.'),
    '#required' => TRUE,
  );

  return system_settings_form($form);
}



/**
 *  Implementation of hook_field_info
 *  Define the fields we're creating
 */
function iiif_image_field_field_info(){
  return array(
    'iiif_image_field' => array(
      'label' => 'IIIF Image',
      'description' => 'Add Images from IIIF Image Server',
      'settings' => array(
        //no settings currently - not sure what we need
      ),
      'instance_settings' => array(
        'allowed_types' => array('libimages')
      ),
      'default_widget' => 'iiif_image_field_widget',
      'default_formatter' => 'iiif_image_field_formatter',
    )
  );
}



/**
 *  Implementation of hook_field_widget_info
 *  Define the widget for inputting 
 */
function iiif_image_field_field_widget_info(){
 return array(
   'iiif_image_field_widget' => array(
     'label' => 'IIIF Image Embed',
     'description' => 'Provides a IIIF Image embed field',
     'field types' => array('iiif_image_field'),
     'settings' => array(),
     'behaviors' => array(
       'multiple values' => FIELD_BEHAVIOR_DEFAULT,
       'default value' => FIELD_BEHAVIOR_DEFAULT
     )
   )
 );
}
/**
*  implementation of hook_field_widget_form
*/
function iiif_image_field_field_widget_form(&$form, &$form_state, $field, $instance, $langcode, $items, $delta, $element){
 //don't need to check the type right now because we're only defining one
 $element += array(
   // '#type' => 'iiif_image_field_widget'
    '#type' => $instance['widget']['type'],
    '#default_value' => isset($items[$delta]) ? $items[$delta] : '',
 );

 $element['iiif_image_id'] = array(
   '#type' => 'textfield',
   '#title' => 'Image ID',
   // Add some js validation/form functions
   //'#attached' => array(
   //  'css' => array(drupal_get_path('module', 'iiif_image_field') . '/iiif_image_field.form.css'),
   //  'js' => array(drupal_get_path('module', 'iiif_image_field') . '/iiif_image_field.form.js'),
   // ),
    '#default_value' => isset($items[$delta]['iiif_image_id'])?$items[$delta]['iiif_image_id']:''
 );

  $element['iiif_image_caption'] = array(
   '#type' => 'textfield',
   '#title' => 'Caption/Label',
   // Add some js validation/form functions
   //'#attached' => array(
   //  'css' => array(drupal_get_path('module', 'iiif_image_field') . '/iiif_image_field.form.css'),
   //  'js' => array(drupal_get_path('module', 'iiif_image_field') . '/iiif_image_field.form.js'),
   // ),
    '#default_value' => isset($items[$delta]['iiif_image_caption'])?$items[$delta]['iiif_image_caption']:''
 );

  $element['iiif_image_rotation'] = array(
   '#type' => 'textfield',
   '#title' => 'Rotation',
   '#size' => 5,
   // Add some js validation/form functions
   //'#attached' => array(
   //  'css' => array(drupal_get_path('module', 'iiif_image_field') . '/iiif_image_field.form.css'),
   //  'js' => array(drupal_get_path('module', 'iiif_image_field') . '/iiif_image_field.form.js'),
   // ),
    '#default_value' => isset($items[$delta]['iiif_image_rotation'])?$items[$delta]['iiif_image_rotation']:''
 );

 return $element;
}

function iiif_image_fields_field_validate($entity_type, $entity, $field, $instance, $langcode, $items, &$errors) {
 foreach ($items as $delta => $item) {
   //check that its a valid id     
 }
}

function iiif_image_field_field_is_empty($item, $field){
 return empty($item);
 if ($field['type'] == 'iiif_image_field') {

    if (empty($item['iiif_image_id']))
    {
      return TRUE;
    }
 }
    return FALSE;
}

//  IIIF Formatter Stuff

function iiif_image_field_field_formatter_info() {
 return array(
   'iiif_image_field_formatter' => array(
     'label' => t('IIIF Image Formatter'),
     'field types' => array('iiif_image_field'),
     'settings' => array(
          'height' => '',
          'width' => '300',
          'region_x' => '0',
          'region_y' => '0',
          'region_h' => '',
          'region_w' => '300',
          'behavior' => 'none',
          'display_first_only' => '0', 
          'display_caption' => '1',
          'rotation' => '0',
          'quality' => 'native',
          'format' => 'jpg'
        ),
     'multiple values' => FIELD_BEHAVIOR_DEFAULT,
   )
 );
}  


/**
*  Implements hook_field_formatter_settings_summary
*/

function iiif_image_field_field_formatter_settings_summary($field, $instance, $view_mode) {
  $display = $instance['display'][$view_mode];
  $settings = $display['settings'];
  $region = $settings['region_x'] . "," . $settings['region_y'] . "," . $settings['region_h'] . "," . $settings['region_w'];
  $dimensions = $settings['height'] . "," . $settings['width'];

  if($settings['display_first_only']) { $first_only = "Only First Image"; } else { $first_only = "All Images"; }
  if($settings['display_caption']) { $caption = "Yes"; } else { $caption = "No"; }
  $summary = '';
  if ($display['type'] == 'iiif_image_field_formatter') {
    $summary = t('Behavior: @behavior', array('@behavior' => $settings['behavior']));
    $summary .= '<br />' . t('Display: @first_only', array('@first_only' => $first_only));
    $summary .= '<br />' . t('Display Caption: @caption', array('@caption' => $caption));
    $summary .= '<br />' . t('Region: @region', array('@region' => $region));
    $summary .= '<br />' . t('Dimensions: @dimensions', array('@dimensions' => $dimensions));
    $summary .= '<br />' . t('Rotation: @rotation', array('@rotation' => $settings['rotation']));
    $summary .= '<br />' . t('Quality: @quality', array('@quality' => $settings['quality']));
    $summary .= '<br />' . t('Format: @format', array('@format' => $settings['format']));
  }
  return $summary;
}


/**
 * Implements hook_field_formatter_settings_form
 */
function iiif_image_field_field_formatter_settings_form($field, $instance, $view_mode, $form, &$form_state) {
  $display = $instance['display'][$view_mode];
  $settings = $display['settings'];

  $element = array();

  if ($display['type'] == 'iiif_image_field_formatter') {
    $element['behavior'] = array(
      '#title' => t('Behavior'),
      '#type' => 'select',
      '#options' => array(
        'none' => t('None'),
        'link_to_content' => t('Link to Content'),
        'zoom' => t('Zoom')
      ),
      '#default_value' => $settings['behavior'],
      '#required' => TRUE,
    );

    $element['display_first_only'] = array(
      '#title' => t('Display First Image Only'),
      '#type' => 'select',
      '#options' => array(
        '0' => t('No'),
        '1' => t('Yes')
      ),
      '#description' => t('If the field is set to be repeatable, select YES if you would like to only display one image for this View Mode. (Hint: recommended for Teaser-like views.)'),
      '#default_value' => $settings['display_first_only'],
      '#required' => TRUE,
    );

    $element['display_caption'] = array(
      '#title' => t('Display Caption'),
      '#type' => 'select',
      '#options' => array(
        '0' => t('No'),
        '1' => t('Yes')
      ),
      '#description' => t('Choose whether or not to display captions for this view mode.'),
      '#default_value' => $settings['display_caption'],
      '#required' => TRUE,
    );

    $element['region_x'] = array(
      '#type' => 'textfield',
      '#size' => '5',
      '#title' => t('Region X'),
      '#description' => t('X-coordinate where cropping begins. '),
      '#default_value' => $settings['region_x'],
    );
    $element['region_y'] = array(
      '#type' => 'textfield',
      '#size' => '5',
      '#title' => t('Region Y'),
      '#description' => t('Y-coordinate where cropping begins.'),
      '#default_value' => $settings['region_y'],
    );
    $element['region_h'] = array(
      '#type' => 'textfield',
      '#size' => '5',
      '#title' => t('Region Height'),
      '#description' => t('Height of the cropped region.'),
      '#default_value' => $settings['region_h'],
    );
    $element['region_w'] = array(
      '#type' => 'textfield',
      '#size' => '5',
      '#title' => t('Region Width'),
      '#description' => t('Width of the cropped region.'),
      '#default_value' => $settings['region_w'],
    );

    $element['height'] = array(
      '#type' => 'textfield',
      '#size' => '5',
      '#title' => t('Height'),
      '#description' => t('Height of the image (after cropping). You can use percentages, pixels, and bangs.'),
      '#default_value' => $settings['height'],
    );
    $element['width'] = array(
      '#type' => 'textfield',
      '#size' => '5',
      '#title' => t('Width'),
      '#description' => t('Width of the image (after cropping).  You can use percentages, pixels, and bangs.'),
      '#default_value' => $settings['width'],
    );


    $element['rotation'] = array(
      '#type' => 'textfield',
      '#size' => '5',
      '#title' => t('Rotation'),
      '#description' => t('The rotation of the image in degrees.  You may enter a number from 0 to 360.  A background will be visible behind images where degrees are not multiples of 90. '),
      '#default_value' => $settings['rotation'],
    );

    $element['quality'] = array(
      '#type'           => 'select',
      '#options'        => array(
          'native' => t('native'),
          'color' => t('color'),
          'grey' => t('grey'),
          'bitonal' => t('bitonal')
      ),
      '#title'          => t('Quality'),
      '#description'    => t('The quality parameter determines the mode of the image - color, greyscale, or black and white.'),
      '#default_value'  => $settings['quality'],
    );

    $element['format'] = array(
      '#type'           => 'select',
      '#options'        => array(
          'jpg' => t('jpg'),
          'png' => t('png'),
          'gif' => t('gif')
      ),
      '#title'          => t('Format'),
      '#description'    => t('The quality parameter determines the mode of the image - color, greyscale, or black and white.'),
      '#default_value'  => $settings['format'],
    );


  }

  return $element;

}



// Paint the field to the display

/**
*  Implements hook_field_formatter_view
*/


function iiif_image_field_field_formatter_view($entity_type, $entity, $field, $instance, $langcode, $items, $display){
  $element = array();
  $delta = 0;

     $element[$delta] = 
      array(
        '#markup' => theme($display['type'], 
          array(
            'element' => $items, 
            'field' => $instance, 
            'settings' => $display['settings'],
            'entity' => $entity
          )
        )
      );



  return $element;

}

/**
 * Implements hook_theme().
 */

function iiif_image_field_theme() {
  return array(
    // The theme function that our formatter uses:
    'iiif_image_field_formatter' => array(
      // Don't forget that all Drupal 7 theme functions have only one argument,
      // so you declare what variables get passed within that argument instead.
      // See http://drupal.org/node/224333#theme_changes
      //'template' => 'iiif_image_field_formatter_iiif_image_field_formatter', 
      'variables' => array('element' => NULL, 'field' => NULL, 'settings' => NULL, 'entity' => NULL),
    ),
  );
}


/**
 * Theme function for 'iiif_image_field_formatter' link field formatter.
 */

function theme_iiif_image_field_formatter($variables) {
  
  $nid = $variables['entity']->nid;
  $node_title = $variables['entity']->title;
  $node_path = drupal_lookup_path('alias', "node/".$nid);
  // assume path_auto, but fall back to node id
  if(empty($node_path)){
    $node_path = "node/".$nid;
  }

  // GET THE IIIF SERVER BASE URI AND API VERSION
  $image_server_base = variable_get('image_server_base', '');
  $image_api_version = variable_get('image_api_version', '1.1');


  $elements = $variables['element'];
  $el_length = sizeof($elements);
  // If Display first only

  if($variables['settings']['display_first_only'] && !empty($variables['element'])){
    $el_length = 1;
  }

  // ACCOMMODATE FOR DIFFERENCES IN API VERSIONS
  $quality = $variables['settings']['quality'];
  if($image_api_version == '2.0'){
    if($variables['settings']['quality'] == 'grey'){
      $quality = 'gray';
    }
    else if($variables['settings']['quality'] == 'native'){
      $quality = 'default';
    }
  }


  // APPLY INSTANCE OVERRIDES TO VIEW MODE SETTINGS
  $rotation = $variables['settings']['rotation'];

  // Zoom Behavior
  if($variables['settings']['behavior'] == 'zoom'){
    $markup = '<div class="viewer"></div>';
    $img_sequence = "";
    $i = 0;
    foreach ($elements as $delta => $el) {
     
      // APPLY INSTANCE OVERRIDES TO VIEW MODE SETTINGS
      if(!empty($el['iiif_image_rotation'])){
        $rotation = $el['iiif_image_rotation'];
      }

      if($i < $el_length && !empty($el['iiif_image_id'])){
              $caption = '';
              if($variables['settings']['display_caption']){
                $caption = $el['iiif_image_caption'];
              }
              $img_sequence .= "{ id: '" . $el['iiif_image_id'] . "', label: '" . $caption . "', rotation: '" . $rotation . "' },";
      }
      $i++;
    }

    drupal_add_css(drupal_get_path('module', 'iiif_image_field') .'/css/font-awesome.min.css');
    drupal_add_css(drupal_get_path('module', 'iiif_image_field') .'/css/iiifOsdViewer.css');
    drupal_add_css('.viewer {
        border: 1px solid #ccc;
        height: 600px;
        width: 800px;
        background: #333;
      }', 'inline');

    drupal_add_js(drupal_get_path('module', 'iiif_image_field') .'/js/jquery-1.11.2.min.js');
    drupal_add_js(drupal_get_path('module', 'iiif_image_field') .'/js/openseadragon.min.js');
    drupal_add_js(drupal_get_path('module', 'iiif_image_field') .'/js/jquery.iiifOsdViewer.js', array('type' => 'file', 'scope' => 'footer', 'weight' => 2));
    drupal_add_js("

    (function ($) {
      $('.viewer' ).addClass( 'rotate". $rotation ."' );
      $('.viewer').iiifOsdViewer({

        data: [{
          iiifServer: '". $image_server_base ."',
          iiifImageAPI: '". $image_api_version ."',
          images: [". $img_sequence ."]}
        ]});

    }(jQuery));",
    array('type' => 'inline', 'scope' => 'footer', 'weight' => 3));

  }else{
    // Non-zoom behaviors
    $markup = "";
    drupal_add_css('figcaption { color: #999999; }', 'inline');
    $i = 0;
    foreach ($elements as $delta => $el) {

        // APPLY INSTANCE OVERRIDES TO VIEW MODE SETTINGS
        if(!empty($el['iiif_image_rotation'])){
          $rotation = $el['iiif_image_rotation'];
        }
        
        if(!empty($el['iiif_image_id']) && $i < $el_length){
        
          $figure = "";

          // Basic "no behavior"
          $figure = "<img src='" . $image_server_base . "/" . $el['iiif_image_id'] . "/full/200,/" . $rotation . "/" . $quality . "." . $variables['settings']['format'] . "'/>";

          // Link to Conent Behavior
          $fig_num = $delta +1;
          if($variables['settings']['behavior'] == 'link_to_content'){
             $figure = '<a href="'. $GLOBALS["base_url"] . '/' . $node_path . '" alt="' . $node_title . '[' . $fig_num  .']">' . $figure . '</a>';
          }

          $figure = "<figure style='display:inline-block'>" . $figure; 

          // If it has a caption or citation use the figure and figcaption elements
          if($variables['settings']['display_caption'] && !empty($el['iiif_image_caption'])){
            $figure .= "<figcaption>" . $el['iiif_image_caption'] . "</figcaption>";
          }

          $figure .= "</figure>";

          $markup .= $figure;
        }
        $i++;
    }

  }


  return $markup;
}