Symfony2 How to create specific collection widget for specific colletion in deep collection form nesting - forms

Question

I have little more complex problem, i have never done more than 1 nested form in an a form, which was fine to just include a custom collection widget template. (Reason: I need to re-code website based on laravel and Spaghetti code, with Spaghetti structure with tons of bugs and buggy patches, what i am fixing for a year now, and i have decided to recreate this app on my loved Symfony).
Let me write the structure:
Questionnaire (short name QN for later use)
- QN -
|_ QN Sections -
|_ QN Parts -
|_ QN Groups -
|_ QN Questions -
|_ some predefined answers
As you can see each QN can have Sections, these sections can have parts, these parts can have groups, and these groups can have questions, these questions have some conditional fields like if question type is "A,B,C" it has another nested collection form for these predefined answers,...
Problem is that for each of these collection form, i need to specify somehow a custom collection wiget template, because each of these collection form has different layout of fields, how they are displayed and handled.
Currently i have created a collection widget template that i include before QN Sections to style QN Sections, but this template is used also for his child collection form, what i need to avoid.
In a perfect world it should work like "prototype_template" => "some path", and then create javascript for each tempalte to add, remove, etc.
Here is an screenshot with some information how it looks now:
In final stage using these separate templates for each collection form, the "form builder" should look like actual web app.
If you need more informations please let me know, i will provide as much informations as i can.
To recap: I need somehow to specify for each nested collection form type to use different collection form widget template.
Thank you

Answer 1

Finnaly I got it.
The main collection template i have used was collection_widget block.
That was bad because it was too general. I hav renamed it to _questionnaire_questionnaireSections_widget, so the 1. level collection were themed. But after day of headake, 1000 combinations of form names i have got how to name the 2. level collection, its block name is "_questionnaire_questionnaireSections_entry_questionnaireParts_widget" what simply stand for "_mainFormTypeName_fieldNameOfFirstCLevelCollection_entry_FieldNameOfSecondLevelCollection_widget"
Than i just needed to place each template file to right place at the right moment.
edit.html.twig
{{ form_start(form) }}
{% form_theme form "::templates/collection/questionnaire/questionnaireSection.html.twig" %}
.........
{{ form_widget(form.questionnaireSections) }}
questionnaireSection.html.twig
{% block _questionnaire_questionnaireSections_widget %}
.............
{% for rows in form %}
{% form_theme form "::templates/collection/questionnaire/questionnairePart.html.twig" %}
questionnairePart.html.twig
{% block _questionnaire_questionnaireSections_entry_questionnaireParts_widget %}
So problem is solved, i have successfully themed nested collections. Thanks to myself and to symfony docs that has 0 words documentation to nested form theming, but they has some information about the "entry " part.