Merge pull request #586 from knjackson30974/Kylea

Added checkbox for option to delete derivatives from datastream.

includes/delete_datastream.form.inc

@@ -19,7 +19,45 @@
  *   The drupal form definition.
  */
 function islandora_delete_datastream_form(array $form, array &$form_state, AbstractDatastream $datastream) {
+  // XXX: Stashed version of datastream is deprecated... Use object and
+  // datastream IDs from 'datastream_info' to acquire.
   $form_state['datastream'] = $datastream;
+
+  $form_state['datastream_info'] = array(
+    'object_id' => $datastream->parent->id,
+    'datastream_id' => $datastream->id,
+  );
+  $object = $datastream->parent;
+  $dsid = $datastream->id;
+  $dsids = array_merge(array($dsid), islandora_datastream_to_purge($object, $dsid));
+  $dsids = array_unique($dsids);
+  $form['delete_derivatives'] = array(
+    '#title' => t('Delete Derviatives'),
+    '#type' => 'checkbox',
+    '#default_value' => 0,
+    '#description' => t('Derivatives can be regenerated at a later time.'),
+  );
+  $form['base_info'] = array(
+    '#type' => 'item',
+    '#title' => t('Datastream to be purged'),
+    '#markup' => $dsid,
+    '#states' => array(
+      'invisible' => array(
+        ':input[name="delete_derivatives"]' => array('checked' => TRUE),
+      ),
+    ),
+  );
+  $form['derivative_info'] = array(
+    '#type' => 'item',
+    '#title' => t('Datastream(s) to be purged'),
+    '#description' => t('Including detectable derivatives.'),
+    '#markup' => implode(', ', $dsids),
+    '#states' => array(
+      'visible' => array(
+        ':input[name="delete_derivatives"]' => array('checked' => TRUE),
+      ),
+    ),
+  );
   return confirm_form($form,
     t('Are you sure you want to delete the %dsid datastream?', array('%dsid' => $datastream->id)),
     "islandora/object/{$datastream->parent->id}",
@@ -29,6 +67,40 @@ function islandora_delete_datastream_form(array $form, array &$form_state, Abstr
   );
 }
 
+/**
+ * Return $dsids based on a given DSID and filter.
+ */
+function islandora_datastream_to_purge(AbstractObject $object, $dsid) {
+  module_load_include('inc', 'islandora', 'includes/utilities');
+  $hooks = islandora_invoke_hook_list(ISLANDORA_DERVIATIVE_CREATION_HOOK, $object->models, array($object));
+  $hook_filter = function ($hook_def) use ($dsid) {
+    return isset($hook_def['source_dsid']) && isset($hook_def['destination_dsid']) ?
+      $hook_def['source_dsid'] == $dsid :
+      FALSE;
+  };
+  $hooks = array_filter($hooks, $hook_filter);
+  $dsid_map = function ($hook_definition) {
+    return $hook_definition['destination_dsid'];
+  };
+  $dsids = array();
+  $derived_dsids = array_map($dsid_map, $hooks);
+  while ($current = array_pop($derived_dsids)) {
+    $dsids[] = $current;
+    $current_derived = islandora_datastream_to_purge($object, $current);
+    $current_diff = array_diff($current_derived, $derived_dsids, $dsids);
+    $derived_dsids = array_merge($derived_dsids, $current_diff);
+  }
+  return $dsids;
+}
+
+/**
+ * Purge a given DSID's derivative datastreams on an object.
+ */
+function islandora_datastream_derivatives_purged(AbstractObject $object, $dsid) {
+  $dsids = islandora_datastream_to_purge($object, $dsid);
+  array_map(array($object, 'purgeDatastream'), $dsids);
+}
+
 /**
  * Submit handler for the delete datastream form.
  *
@@ -44,10 +116,14 @@ function islandora_delete_datastream_form(array $form, array &$form_state, Abstr
  *   The Drupal form state.
  */
 function islandora_delete_datastream_form_submit(array $form, array &$form_state) {
-  $datastream = $form_state['datastream'];
-  $datastream_id = $datastream->id;
-  $object = $datastream->parent;
+  $object = islandora_object_load($form_state['datastream_info']['object_id']);
+  $datastream_id = $form_state['datastream_info']['datastream_id'];
+  $datastream = $object[$datastream_id];
+
   $deleted = FALSE;
+  if ($form_state['values']['delete_derivatives']) {
+    islandora_datastream_derivatives_purged($object, $datastream_id);
+  }
   try {
     $deleted = islandora_delete_datastream($datastream);
   }