# frozen_string_literal: true

module JsonApiToolbox
  module Postable
    class << self
      def normalize_post(hash, model)
        associations = model.reflect_on_all_associations.map(&:name)
        normalized_hash = hash.map do |key, value|
          child_model = association_class(model, key) if value.is_a? Hash
          key = associations.include?(key.to_sym) ? "#{key}_attributes" : key
          hash_value = check_child_association(value, key, model, child_model)
          [key, hash_value]
        end
        Hash[normalized_hash]
      end

      private

      def association_class(model, key)
        association = model.reflect_on_all_associations.find do |association_i|
          association_i.name.to_s == key.to_s
        end
        return false unless association
        class_name = (association.options.symbolize_keys[:class_name] || key)
        ActiveSupport::Inflector.singularize(class_name).camelize.constantize
      end

      def check_child_association(value, key, model, child_model)
        if value.is_a?(Hash) && !model.has_attribute?(key)
          normalize_post(value, child_model)
        else
          value
        end
      end
    end
  end
end