From ddc5ad96db347e60c659aa756ecbd0e7e5528f12 Mon Sep 17 00:00:00 2001
From: jonathangreen <jonathan@discoverygarden.ca>
Date: Wed, 30 May 2012 12:59:02 -0300
Subject: [PATCH] Breadcrumbs

---
 includes/Breadcrumbs.inc | 78 ++++++++++++++++++++++++++++++++++++++++
 islandora.module         |  2 ++
 2 files changed, 80 insertions(+)
 create mode 100644 includes/Breadcrumbs.inc

diff --git a/includes/Breadcrumbs.inc b/includes/Breadcrumbs.inc
new file mode 100644
index 00000000..eb36111c
--- /dev/null
+++ b/includes/Breadcrumbs.inc
@@ -0,0 +1,78 @@
+<?php
+
+function islandora_get_breadcrumbs($pid) {
+  module_load_include('inc', 'islandora', 'RestConnection');
+  $breadcrumbs = array();
+
+  $connection = new RestConnection();
+  islandora_get_breadcrumbs_recursive($pid, $breadcrumbs, $connection->repository);
+  
+  if(isset($breadcrumbs[0])) {
+    unset($breadcrumbs[0]);
+  }
+
+  $breadcrumbs = array_reverse($breadcrumbs);
+
+  return $breadcrumbs;
+}
+
+/**
+ * Builds an array of drupal links for use in breadcrumbs.
+ *
+ * @todo Make fully recursive...
+ *
+ * @global type $base_url
+ * @param type $pid
+ * @param type $breadcrumbs
+ * @param type $level
+ */
+function islandora_get_breadcrumbs_recursive($pid, &$breadcrumbs, $repository) {
+  // Before executing the query, we hve a base case of accessing the top-level collection
+  global $base_url;
+  static $max_level = 10;
+  static $level = -1;
+
+  if (count($breadcrumbs) === 0) {
+    $level = $max_level;
+  }
+
+  $root = variable_get('islandora_repository_pid', 'islandora:root');
+  if ($pid == $root) {
+    $breadcrumbs[] = l(menu_get_active_title(), 'islandora');
+    $breadcrumbs[] = l(t('Home'), '<front>');
+  }
+  else {
+    $query_string = 'select $parentObject $title $content from <#ri>
+                      where (
+                        <info:fedora/' . $pid . '> <fedora-model:label> $title
+                        and $parentObject <fedora-model:hasModel> $content
+                        and (
+                          <info:fedora/' . $pid . '> <fedora-rels-ext:isMemberOfCollection> $parentObject
+                          or <info:fedora/' . $pid . '> <fedora-rels-ext:isMemberOf> $parentObject
+                          or <info:fedora/' . $pid . '> <fedora-rels-ext:isPartOf> $parentObject
+                        )
+                        and $parentObject <fedora-model:state> <info:fedora/fedora-system:def/model#Active>
+                      )
+                      minus $content <mulgara:is> <info:fedora/fedora-system:FedoraObject-3.0>
+                      order by $title desc';
+    $results = $repository->ri->itqlQuery($query_string);
+
+    if (count($results) > 0  && $level > 0) {
+      $parent = $results[0]['parentObject']['value'];
+      $this_title = $results[0]['title']['value'];
+
+      if (empty($this_title)) {
+        $this_title = t('-');
+      }
+
+      $breadcrumbs[] = l($this_title, "islandora/object/$pid");
+
+      $level--;
+      islandora_get_breadcrumbs_recursive($parent, $breadcrumbs, $repository);
+    }
+    else {
+      $breadcrumbs[] = '...'; //Add an non-link, as we don't know how to get back to the root.
+      islandora_get_breadcrumbs_recursive($root, $breadcrumbs, $repository); //And render the last two links and break (on the next pass).
+    }
+  }
+}
\ No newline at end of file
diff --git a/islandora.module b/islandora.module
index 76697a1e..3e1dabe3 100644
--- a/islandora.module
+++ b/islandora.module
@@ -480,6 +480,8 @@ function islandora_view_default_object() {
  * @return string 
  */
 function islandora_view_object($object_id = NULL) {
+  module_load_include('inc', 'islandora', 'includes/Breadcrumbs');
+  drupal_set_breadcrumb(islandora_get_breadcrumbs($object_id));
   //return $object_id;
   if (!isset($object_id)) {
     $object_id = variable_get('islandora_repository_pid', 'islandora:root');