how to get weight or delta of current field collection item that is being computed [closed]

Question

Is it possible to get weight(order index) of multi field "field collection".This weight is needed inside computed field which is inside field collection.I tried the following but it returns empty

$wrapper = entity_metadata_wrapper('field_collection_item', $entity);    
$instance = field_read_instance('field_collection_item',$wrapper, 'bundle_name');
dpm($instance['widget']['weight']);

Here is the structure

main_content-contains field collection (multi value)
------field collection(s)-contains 1 text field and 1 computed field
------|----item 0
------|-------|-------computed_field <---here how to get weight of field collection item ie 0
------|----item 1
------|-------|-------computed_field <---here how to get weight of field collection item ie 1
------|----item 2
------|-------|-------computed_field
------|----item n
------|-------|-------computed_field

Answer 1

I was searching in wrong path :( this is found at

http://drupalcontrib.org/api/drupal/contributions!field_collection!field_collection.module/class/FieldCollectionItemEntity/7

code for getting delta is

$wrapper = entity_metadata_wrapper('field_collection_item', $entity);
$cur_delta=$wrapper->delta();