series.rb in groupdate-1.0.2

- old
+ new

@@ -1,27 +1,28 @@
 module Groupdate
   class Series
 
-    def initialize(relation, field, column, time_zone, time_range)
+    def initialize(relation, field, column, time_zone, time_range, week_start)
       @relation = relation
       if time_range.is_a?(Range)
         @relation = relation.where("#{column} BETWEEN ? AND ?", time_range.first, time_range.last)
       end
       @field = field
       @time_zone = time_zone
       @time_range = time_range
+      @week_start = week_start
     end
 
     def build_series(count)
       utc = ActiveSupport::TimeZone["UTC"]
 
       cast_method =
         case @field
         when "day_of_week", "hour_of_day"
           lambda{|k| k.to_i }
         else
-          lambda{|k| (k.is_a?(Time) ? k : utc.parse(k)).utc }
+          lambda{|k| (k.is_a?(String) ? utc.parse(k) : k.to_time).utc }
         end
 
       count = Hash[count.map do |k, v|
         [cast_method.call(k), v]
       end]
@@ -53,11 +54,12 @@
             when "hour"
               time.change(:min => 0)
             when "day"
               time.beginning_of_day
             when "week"
-              # beginning_of_week does not support :sunday argument in activesupport < 3.2
-              (time - time.wday.days).midnight
+              # same logic as MySQL group
+              weekday = (time.wday - 1) % 7
+              (time - ((7 - @week_start + weekday) % 7).days).midnight
             when "month"
               time.beginning_of_month
             else # year
               time.beginning_of_year
             end