methods for validated attributes for write cache and before type cast

cache raw value in @attributes_cache which is AR convention but should
work fine with non-AR ORM
before type cast method for reading back cached raw value

lib/validates_timeliness.rb

@@ -29,13 +29,17 @@ module ValidatesTimeliness
   # Setup method for plugin configuration
   def self.setup
     yield self
-    extend_classes.each {|klass| klass.send(:include, ValidatesTimeliness::HelperMethods) }
+    extend_classes.each {|klass|
+      klass.send(:include, ValidatesTimeliness::HelperMethods)
+      klass.send(:include, ValidatesTimeliness::AttributeMethods)
+    }
   end
 end
 
 require 'validates_timeliness/conversion'
 require 'validates_timeliness/validator'
 require 'validates_timeliness/helper_methods'
+require 'validates_timeliness/attribute_methods'
 require 'validates_timeliness/extensions'
 require 'validates_timeliness/version'
 

lib/validates_timeliness/attribute_methods.rb

@@ -0,0 +1,43 @@
+module ValidatesTimeliness
+  module AttributeMethods
+    extend ActiveSupport::Concern
+
+    included do
+      attribute_method_suffix "_before_type_cast"
+    end
+
+    module ClassMethods
+
+      protected
+
+      def define_method_attribute=(attr_name)
+        if timeliness_validated_attributes.include?(attr_name)
+          method_body, line = <<-EOV, __LINE__ + 1
+            def #{attr_name}=(value)
+              @attributes_cache ||= {}
+              @attributes_cache["_#{attr_name}_before_type_cast"] = value
+              super
+            end
+          EOV
+          class_eval(method_body, __FILE__, line)
+        else
+          super
+        end
+      end
+
+      def define_method_attribute_before_type_cast(attr_name)
+        if timeliness_validated_attributes.include?(attr_name)
+          method_body, line = <<-EOV, __LINE__ + 1
+            def #{attr_name}_before_type_cast
+              @attributes_cache && @attributes_cache["_#{attr_name}_before_type_cast"]
+            end
+          EOV
+          class_eval(method_body, __FILE__, line)
+        else
+          super rescue(NoMethodError)
+        end
+      end
+
+    end
+  end
+end

lib/validates_timeliness/helper_methods.rb

@@ -20,5 +20,15 @@ module ValidatesTimeliness
         validates_with Validator, _merge_attributes(attr_names).merge(:type => :datetime)
       end
     end
+
+    module ClassMethods
+      def timeliness_validated_attributes
+        @timeliness_validated_attributes ||= begin
+          _validators.map do |attr_name, validators|
+            attr_name.to_s if validators.any? {|v| v.is_a?(ValidatesTimeliness::Validator) }
+          end.compact
+        end
+      end
+    end
   end
 end