Write a custom module for a website based on Drupal (Involving fields, search api, node add form)

General information/requirements The whole work is conducted in the development website www.freesbee2.krown.ch. The website allows user to publish ads to rent/hire objects and services. When user publishes an ad, he musts select a category of object/service. This category is a key point in the website, because it allows the whole search/categorization system. There are approximately 19 parent categories, and about 110 sub categories. Each parent category has a color assigned. Each sub category has specific fields to be completed by the user. When user interact with the category dropdown in the node add form, the page and form must change dynamically (colors + dependent fields). All categories are described in the external documents. Please note that at this moment only the parent Category. The search system is based on Search API drupal module. Each field needs to be compatible with this module, so we can perform search through it and add facet filters. The fields must be translatable (module Internationalization ). All new features must be compatible with the whole actual system. So they have to be based on standard drupal field. The new fields must be compatible and consistent with the existent Design. Please refer to the file “Category - Véhicules – Voiture” for an example of perfect category layout. The list options and dispositions must be exactly conforming as external documents. Key Tasks Add all fields in accordance to external documents, by category. Change the current configuration. At this moment all fields are preloaded in DOM when you go to http://www. [login to view URL], then the fields dependent on category are loaded in JS when user select a sub category. This configuration is causing browser lag when loading the page so this need to be improved. Change JS behavior when displaying dependent fields (after selecting a sub category in the dropdown) to AJAX behavior. Actually the dependent sub categories must load in AJAX only on demand, so the browser load only the necessary. Therefore the only fields that must be loaded on load page are the one visible in the first image of this document. Create required Content Types for each category or only sub category and add required fields.