Handle project tags duplication

app/Model/ProjectDuplicationModel.php

@@ -22,7 +22,15 @@ class ProjectDuplicationModel extends Base
      */
     public function getOptionalSelection()
     {
-        return array('categoryModel', 'projectPermissionModel', 'actionModel', 'swimlaneModel', 'taskModel', 'projectMetadataModel');
+        return array(
+            'categoryModel',
+            'projectPermissionModel',
+            'actionModel',
+            'swimlaneModel',
+            'tagDuplicationModel',
+            'projectMetadataModel',
+            'taskModel',
+        );
     }
 
     /**
@@ -33,7 +41,16 @@ class ProjectDuplicationModel extends Base
      */
     public function getPossibleSelection()
     {
-        return array('boardModel', 'categoryModel', 'projectPermissionModel', 'actionModel', 'swimlaneModel', 'taskModel', 'projectMetadataModel');
+        return array(
+            'boardModel',
+            'categoryModel',
+            'projectPermissionModel',
+            'actionModel',
+            'swimlaneModel',
+            'tagDuplicationModel',
+            'projectMetadataModel',
+            'taskModel',
+        );
     }
 
     /**

app/Model/TagDuplicationModel.php

@@ -12,6 +12,26 @@ use Kanboard\Core\Base;
  */
 class TagDuplicationModel extends Base
 {
+    /**
+     * Duplicate project tags to another project
+     *
+     * @access public
+     * @param  integer $src_project_id
+     * @param  integer $dst_project_id
+     * @return bool
+     */
+    public function duplicate($src_project_id, $dst_project_id)
+    {
+        $tags = $this->tagModel->getAllByProject($src_project_id);
+        $results = array();
+
+        foreach ($tags as $tag) {
+            $results[] = $this->tagModel->create($dst_project_id, $tag['name']);
+        }
+
+        return ! in_array(false, $results, true);
+    }
+
     /**
      * Link tags to the new tasks
      *