1 files changed, 63 insertions, 0 deletions
diff --git a/lib/redmine/utils.rb b/lib/redmine/utils.rb
index cfdb4d15d..b68c53470 100644
--- a/lib/redmine/utils.rb
+++ b/lib/redmine/utils.rb
@@ -51,5 +51,68 @@ module Redmine
         end
       end
     end
+
+    module DateCalculation
+      # Returns the number of working days between from and to
+      def working_days(from, to)
+        days = (to - from).to_i
+        if days > 0
+          weeks = days / 7
+          result = weeks * (7 - non_working_week_days.size)
+          days_left = days - weeks * 7
+          start_cwday = from.cwday
+          days_left.times do |i|
+            unless non_working_week_days.include?(((start_cwday + i - 1) % 7) + 1)
+              result += 1
+            end
+          end
+          result
+        else
+          0
+        end
+      end
+
+      # Adds working days to the given date
+      def add_working_days(date, working_days)
+        if working_days > 0
+          weeks = working_days / (7 - non_working_week_days.size)
+          result = weeks * 7
+          days_left = working_days - weeks * (7 - non_working_week_days.size)
+          cwday = date.cwday
+          while days_left > 0
+            cwday += 1
+            unless non_working_week_days.include?(((cwday - 1) % 7) + 1)
+              days_left -= 1
+            end
+            result += 1
+          end
+          next_working_date(date + result)
+        else
+          date
+        end
+      end
+
+      # Returns the date of the first day on or after the given date that is a working day
+      def next_working_date(date)
+        cwday = date.cwday
+        days = 0
+        while non_working_week_days.include?(((cwday + days - 1) % 7) + 1)
+          days += 1
+        end
+        date + days
+      end
+
+      # Returns the index of non working week days (1=monday, 7=sunday)
+      def non_working_week_days
+        @non_working_week_days ||= begin
+          days = Setting.non_working_week_days
+          if days.is_a?(Array) && days.size < 7
+            days.map(&:to_i)
+          else
+            []
+          end
+        end
+      end
+    end
   end
 end