Changes required for metadata display refinements.

includes/metadata.inc

@@ -0,0 +1,123 @@
+<?php
+/**
+ * @file
+ * Defines functions used when viewing metadata displays on Islandora objects.
+ */
+
+/**
+ * Retrieves the metadata display markup for an Islandora object.
+ *
+ * @param AbstractObject $object
+ *   An AbstractObject representing an object within Fedora.
+ *
+ * @return string
+ *   Markup to be rendered for display on Islandora object pages.
+ */
+function islandora_retrieve_metadata_markup(AbstractObject $object) {
+  $viewers = module_invoke_all('islandora_metadata_display_info');
+  $viewer = variable_get('islandora_metadata_display', 'dublin_core');
+
+  if (isset($viewers[$viewer]['callback'])) {
+    return call_user_func($viewers[$viewer]['callback'], $object);
+  }
+  else {
+    return '';
+  }
+}
+
+/**
+ * Form used for choosing which default metadata display to use for viewing.
+ *
+ * @param array $form
+ *   An array representing a Drupal form.
+ * @param array $form_state
+ *   An array containing the Drupal form state.
+ *
+ * @return array
+ *   An array representing the metadata display viewer form.
+ */
+function islandora_metadata_display_form($form, $form_state) {
+  module_load_include('inc', 'islandora', 'includes/solution_packs.inc');
+  $form = array();
+  $defined_displays = module_invoke_all('islandora_metadata_display_info');
+  if (!empty($defined_displays)) {
+    $no_viewer = array();
+    $no_viewer['none'] = array(
+      'label' => t('None'),
+      'description' => t("Don't show any metadata for displaying"),
+    );
+    $viewers = array_merge_recursive($no_viewer, $defined_displays);
+
+    $form['viewers'] = array(
+      '#type' => 'item',
+      '#title' => t('Select a viewer'),
+      '#description' => t('Preferred metadata display for Islandora. These may be provided by third-party modules.'),
+      '#tree' => TRUE,
+      '#theme' => 'islandora_viewers_table',
+    );
+
+    foreach ($viewers as $name => $profile) {
+      $options[$name] = '';
+      $form['viewers']['name'][$name] = array(
+        '#type' => 'hidden',
+        '#value' => $name,
+      );
+      $form['viewers']['label'][$name] = array(
+        '#type' => 'item',
+        '#markup' => $profile['label'],
+      );
+      $form['viewers']['description'][$name] = array(
+        '#type' => 'item',
+        '#markup' => $profile['description'],
+      );
+      $form['viewers']['configuration'][$name] = array(
+        '#type' => 'item',
+        '#markup' => (isset($profile['configuration']) AND $profile['configuration'] != '') ? l(t('configure'), $profile['configuration']) : '',
+      );
+    }
+    $form['viewers']['default'] = array(
+      '#type' => 'radios',
+      '#options' => isset($options) ? $options : array(),
+      '#default_value' => variable_get('islandora_metadata_display', 'dublin_core'),
+    );
+  }
+  else {
+    $form['viewers']['no_viewers'] = array(
+      '#markup' => t('No viewers detected.'),
+    );
+  }
+  $form['submit'] = array(
+    '#type' => 'submit',
+    '#value' => t('Save configuration'),
+  );
+  return $form;
+}
+
+/**
+ * Submit handler for the metadata display form which sets the default viewer.
+ *
+ * @param array $form
+ *   An array representing a Drupal form.
+ * @param array $form_state
+ *   An array containing the Drupal form state.
+ */
+function islandora_metadata_display_form_submit($form, $form_state) {
+  variable_set('islandora_metadata_display', $form_state['values']['viewers']['default']);
+  drupal_set_message(t('The configuration options have been saved.'));
+}
+
+/**
+ * Metadata display callback for rendering Dublin Core metadata.
+ *
+ * @param AbstractObject $object
+ *   An AbstractObject representing an object within Fedora.
+ *
+ * @return string
+ *   Markup representing the rendered metadata from Dublin Core.
+ */
+function islandora_metadata_display_callback(AbstractObject $object) {
+  $elements = array(
+    'islandora_object' => $object,
+  );
+  return theme('islandora_dublin_core_display', $elements);
+}

islandora.api.php

@@ -691,3 +691,31 @@ function hook_islandora_update_related_objects_properties(AbstractObject $object
 function hook_islandora_breadcrumbs_alter(&$breadcrumbs, $context) {
 
 }
+
+/**
+ * Registry hook for metadata display viewers.
+ *
+ * Modules can use this hook to override the default Dublin Core display.
+ * This hook lets Islandora know which viewers there are available.
+ *
+ * @return array
+ *   An associative array where the values are the following:
+ *   -label: Human readable display label for selection.
+ *   -description: A description of what the metadata display viewer does.
+ *   -callback: A callable function that provides the markup to be passed
+ *    off to the template files.
+ *   -configuration (Optional): A path to the administration page for the
+ *    metadata display.
+
+ * @see islandora_retrieve_metadata_markup()
+ */
+function hook_islandora_metadata_display_info() {
+  return array(
+    'hookable_displays_yay' => array(
+      'label' => t('Hookable display yay!'),
+      'description' => t('This is purely an example of how to implement this.'),
+      'callback' => 'hookable_displays_some_function_that_returns_markup',
+      'configuration' => 'admin/hookable_displays_yay/somepath',
+    ),
+  );
+}

islandora.module

@@ -99,6 +99,14 @@ function islandora_menu() {
     'type' => MENU_NORMAL_ITEM,
     'weight' => -1,
   );
+  $items['admin/islandora/metadata'] = array(
+    'title' => 'Metadata Display',
+    'description' => 'Configure settings for metadata display on Islandora objects',
+    'page callback' => 'drupal_get_form',
+    'page arguments' => array('islandora_metadata_display_form'),
+    'file' => 'includes/metadata.inc',
+    'access arguments' => array('adminisiter site configuration'),
+  );
   $items['admin/islandora/solution_packs'] = array(
     'title' => 'Solution packs',
     'description' => 'Install content models and collections required by installed solution packs.',
@@ -445,6 +453,17 @@ function islandora_theme() {
       'file' => 'theme/theme.inc',
       'variables' => array('datastream' => NULL),
     ),
+    'islandora_dublin_core_display' => array(
+      'file' => 'theme/theme.inc',
+      'template' => 'theme/islandora-dublin-core-display',
+      // We can add PIDs to the end of this pattern in our preprocess function
+      // and templates will be able to have have a pid appended to the
+      // template name to overide a template on a per object basis.
+      // An example template might be named:
+      // "islandora-dublin-core-display--islandora-27.tpl.php".
+      'pattern' => 'islandora_dublin_core_display__',
+      'variables' => array('islandora_object' => NULL),
+    ),
   );
 }
 
@@ -1602,3 +1621,16 @@ function islandora_islandora_datastream_modified(AbstractObject $object, Abstrac
   ));
   islandora_derivative_logging($logging_results);
 }
+
+/**
+ * Implements hook_islandora_metadata_display_info().
+ */
+function islandora_islandora_metadata_display_info() {
+  return array(
+    'dublin_core' => array(
+      'label' => t('Dublin Core'),
+      'description' => t('Dublin Core metadata'),
+      'callback' => 'islandora_metadata_display_callback',
+    ),
+  );
+}

theme/islandora-dublin-core-display.tpl.php

@@ -0,0 +1,17 @@
+<fieldset class="collapsible collapsed">
+  <legend><span class="fieldset-legend"><?php print t('Details'); ?></span></legend>
+  <div class="fieldset-wrapper">
+    <dl xmlns:dcterms="http://purl.org/dc/terms/" class="islandora-inline-metadata islandora-metadata-fields">
+      <?php $row_field = 0; ?>
+      <?php foreach($dc_array as $key => $value): ?>
+        <dt property="<?php print $value['dcterms']; ?>" content="<?php print $value['value']; ?>" class="<?php print $value['class']; ?><?php print $row_field == 0 ? ' first' : ''; ?>">
+          <?php print $value['label']; ?>
+        </dt>
+        <dd class="<?php print $value['class']; ?><?php print $row_field == 0 ? ' first' : ''; ?>">
+          <?php print $value['value']; ?>
+        </dd>
+        <?php $row_field++; ?>
+      <?php endforeach; ?>
+    </dl>
+  </div>
+</fieldset>

theme/theme.inc

@@ -423,3 +423,21 @@ function theme_islandora_datastream_version_link(array $vars) {
     return '';
   }
 }
+
+/**
+ * Implements hook_preprocess().
+ */
+function islandora_preprocess_islandora_dublin_core_display(array &$variables) {
+  $islandora_object = $variables['islandora_object'];
+  if (islandora_datastream_access(ISLANDORA_VIEW_OBJECTS, $islandora_object['DC'])) {
+    try {
+      $dc = $islandora_object['DC']->content;
+      $dc_object = DublinCore::importFromXMLString($dc);
+    }
+    catch (Exception $e) {
+      drupal_set_message(t('Error retrieving object %s %t', array('%s' => $islandora_object->id, '%t' => $e->getMessage())), 'error', FALSE);
+    }
+  }
+  $variables['islandora_dublin_core'] = isset($dc_object) ? $dc_object : NULL;
+  $variables['dc_array'] = isset($dc_object) ? $dc_object->asArray() : array();
+}