refactored action view extension to use params

this is instead of value before type to avoid issues with partial value parsing
will be extracted in v3

lib/validates_timeliness/action_view/instance_tag.rb

@@ -1,3 +1,4 @@
+# TODO remove this from the plugin for v3.
 module ValidatesTimeliness
 
   def self.enable_datetime_select_invalid_value_extension!
@@ -6,13 +7,10 @@ module ValidatesTimeliness
 
   module ActionView
 
-    # Intercepts the date and time select helpers to allow the
-    # attribute value before type cast to be used as in the select helpers.
-    # This means that an invalid date or time will be redisplayed rather than the
-    # type cast value which would be nil if invalid.
-    #
-    # Its a minor user experience improvement to be able to see original value
-    # entered to aid correction.
+    # Intercepts the date and time select helpers to reuse the values from the
+    # the params rather than the parsed value. This allows invalid date/time
+    # values to be redisplayed instead of blanks to aid correction by the user.
+    # Its a minor usability improvement which is rarely an issue for the user.
     #
     module InstanceTag
 
@@ -33,19 +31,19 @@ module ValidatesTimeliness
       end
 
       def value_with_timeliness(object)
-        return value_without_timeliness(object) unless @timeliness_date_or_time_tag
-
-        raw_value = value_before_type_cast(object)
-
-        if raw_value.nil? || raw_value.acts_like?(:time) || raw_value.is_a?(Date)
+        unless @timeliness_date_or_time_tag && @template_object.params[@object_name]
           return value_without_timeliness(object)
         end
 
-        date, time = raw_value.split(' ')
-        date_array = date.split('-')
-        time_array = time.split(':')
+        pairs = @template_object.params[@object_name].select {|k,v| k =~ /^#{@method_name}\(/ }
+        return value_without_timeliness(object) if pairs.empty?
 
-        TimelinessDateTime.new(*(date_array + time_array).map {|v| v.blank? ? nil : v.to_i})
+        values = pairs.map do |(param, value)|
+          position = param.scan(/\(([0-9]*).*\)/).first.first
+          [position, value]
+        end.sort {|a,b| a[0] <=> b[0] }.map {|v| v[1] }
+
+        TimelinessDateTime.new(*values)
       end
 
     end