модель FieldsObject

fields_object.rb

class FieldsObject
  include Mongoid::Document
  include Mongoid::Timestamps
  @@field_types = [
        :array,
        :big_decimal,
        :boolean,
        :date,
        :date_time,
        :float,
        :hash,
        :integer,
        :range,
        :string,
        :symbol,
        :time,
      ]

  attr_accessor :field_type, :value

  embedded_in :layers_object

  field :key, type: Symbol
  field :field_type_code, type: Integer

  field :array_value, type: Array
  field :big_decimal_value, type: BigDecimal
  field :boolean_value, type: Boolean
  field :date_value, type: Date
  field :date_time_value, type: DateTime
  field :float_value, type: Float
  field :hash_value, type: Hash
  field :integer_value, type: Integer
  field :range_value, type: Range
  field :string_value, type: String
  field :symbol_value, type: Symbol
  field :time_value, type: Time

  before_validation :set_fields
  after_save :clear_temp_attributes

  def value
    if new_record?
      @value ||= attributes["value"]
    else
      @value ||= self.send(value_field.to_sym)
    end
  end

  def field_type
    if new_record?
      @field_type ||= attributes["field_type"]
    else
      @field_type ||= @@field_types[field_type_code]
    end
  end

  private

  def value_field
    "#{field_type}_value"
  end

  def set_fields
    self.send("#{ value_field }=".to_sym, value)
    self.field_type_code = @@field_types.index(field_type) if new_record?
  end

  def clear_temp_attributes
    @value = nil
    @field_type = nil
  end

end