json attr_accessor

module ActiveRecord
  module Type
    class Json < ActiveModel::Type::Value
      include ActiveModel::Type::Helpers::Mutable
      def deserialize(value)
        value = '{}' if value.is_a?(::NilClass)
        return value unless value.is_a?(::String)
        ActiveSupport::JSON.decode(value) rescue nil
      end
    end
  end
end



module ActiveRecordConcern

  def json_attr_accessible(args = {})
    # binding.pry
    column    = args[:json_column].to_s
    key_names = args[:key_names]

    # {
    #     :json_column => :data,
    #       :key_names => [
    #         {
    #             :name => :card_type
    #         },
    #         {
    #               :name => :high,
    #             :parent => :apr
    #         },
    #         {
    #                           :name => :low,
    #                         :parent => :apr,
    #             :prefix_column_name => true
    #             :fall_back => :product
    #         }
    #     ]
    # }

    key_names.each do |hsh|
      method_name = hsh[:child] ? "#{hsh[:name]}_#{hsh[:child]}" : hsh[:name]
      method_name = "#{hsh[:json_column]}_#{method_name}" if hsh[:prefix_column_name] == true
      
      define_method("#{method_name}=") do |val|
        # self.send("#{column}=", {}) if self.send(column).nil?
        # send("#{serialized_attribute_name}_will_change!")
        if hsh[:child]
          (send(column)[hsh[:name].to_s] ||= {})[hsh[:child].to_s] = val
        else
          send(column)[hsh[:name].to_s] = val
        end
      end

      # if hsh[:fallback]
      define_method("#{method_name}_no_fallback") do
        if hsh[:child]
          read_attribute(column)[hsh[:name].to_s].try(:[], hsh[:child].to_s)
        else
          read_attribute(column)[hsh[:name].to_s]
        end
      end
      # end

      define_method("#{method_name}") do
        if hsh[:fallback]
          val = send("#{method_name}_no_fallback")
          return val if val.present?
          fallback_item = send(hsh[:fallback])
          fallback_item.try(:send, method_name)
        else
          send("#{method_name}_no_fallback")
        end
      end

      define_method("#{method_name}?") do
        send(method_name).present?
      end
      
      # attr_accessible "#{serialized_attribute_name}_#{name}"
    end
  end


  extend ActiveRecordConcern
  belongs_to :product, required: false
  
  delegate :payout,
    to: :product

  attr_accessible_with_fallback(:product, 
    :description
  )

  json_attr_accessible( {
    json_column: :data,
    key_names: [
      { name: :card_type, fallback: :product },
      { name: :apr, child: :high },
      { name: :apr, child: :low, prefix_column_name: true },
    ],
  })