2 files changed, 53 insertions, 6 deletions
diff --git a/modules/gallery/models/cache.php b/modules/gallery/models/cache.php
new file mode 100644
index 00000000..99e19a6e
--- /dev/null
+++ b/modules/gallery/models/cache.php
@@ -0,0 +1,20 @@
+<?php defined("SYSPATH") or die("No direct script access.");
+/**
+ * Gallery - a web based photo album viewer and editor
+ * Copyright (C) 2000-2009 Bharat Mediratta
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or (at
+ * your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston, MA  02110-1301, USA.
+ */
+class Cache_Model extends ORM {}
diff --git a/modules/gallery/models/item.php b/modules/gallery/models/item.php
index 7dce9e51..430119b5 100644
--- a/modules/gallery/models/item.php
+++ b/modules/gallery/models/item.php
@@ -378,14 +378,41 @@ class Item_Model extends ORM_MPTT {
    * the first child in the album is at position 1.
    */
   public function get_position($child_id) {
-    $result = Database::instance()->query("
+    if ($this->sort_order == "DESC") {
+      $comp = ">";
+    } else {
+      $comp = "<";
+    }
+
+    $db = Database::instance();
+    $position = $db->query("
       SELECT COUNT(*) AS position FROM {items}
-       WHERE parent_id = {$this->id}
-         AND {$this->sort_column} <= (SELECT {$this->sort_column}
-                                        FROM {items} WHERE id = $child_id)
-       ORDER BY {$this->sort_column} {$this->sort_order}");
+      WHERE parent_id = {$this->id}
+        AND `{$this->sort_column}` $comp (SELECT `{$this->sort_column}`
+                                          FROM {items} WHERE id = $child_id)
+      ORDER BY `{$this->sort_column}` {$this->sort_order}")->current()->position;
+
+    // We stopped short of our target value in the sort (notice that we're using a < comparator
+    // above) because it's possible that we have duplicate values in the sort column.  An
+    // equality check would just arbitrarily pick one of those multiple possible equivalent
+    // columns, which would mean that if you choose a sort order that has duplicates, it'd pick
+    // any one of them as the child's "position".
+    //
+    // Fix this by doing a 2nd query where we iterate over the equivalent columns and add them to
+    // our base value.
+    $result = $db->query("
+      SELECT id FROM {items}
+      WHERE parent_id = {$this->id}
+        AND `{$this->sort_column}` = (SELECT `{$this->sort_column}`
+                                      FROM {items} WHERE id = $child_id)");
+    foreach ($result as $row) {
+      $position++;
+      if ($row->id == $child_id) {
+        break;
+      }
+    }
 
-    return $result->current()->position;
+    return $position;
   }
 
   /**