Send monthly reports

app/models/reading.rb

@@ -67,6 +67,16 @@ class Reading < ActiveRecord::Base
     def day(date)
       Reading.where("created_at > :begin AND created_at < :end", { :begin => date.to_date.beginning_of_day, :end => date.to_date.end_of_day})        
     end
+
+    def in_month(date)
+      hour_start = date.beginning_of_month.beginning_of_day
+      hour_end = date.end_of_month.end_of_day
+      # can't get cost for the future
+      hour_end = Time.now if hour_end > Time.now
+
+      Reading.where("created_at > :begin AND created_at < :end", { :begin => hour_start, :end => hour_end})  
+
+    end  
     
     def max_charge_kwh=(kwh)
       @@max_charge_kwh = kwh
@@ -78,12 +88,19 @@ class Reading < ActiveRecord::Base
     
     # do not make distinction between high and low consumption/production
     def consumed_and_produced_for_diff(d)
-
       usage_kwh = (d[:total_kwh_consumed_high].nil? || d[:total_kwh_consumed_low].nil?) ? nil :  d[:total_kwh_consumed_high] + d[:total_kwh_consumed_low] 
       return_kwh = (d[:total_kwh_produced_high].nil? || d[:total_kwh_produced_low].nil?) ? nil : d[:total_kwh_produced_high] + d[:total_kwh_produced_low]
 
       return usage_kwh, return_kwh
     end
+
+    # calculate net_consumption (= consumption-production)
+    def net_consumed_high_and_low_for_diff(d)
+      net_consumed_high = (d[:total_kwh_consumed_high].nil? || d[:total_kwh_produced_high].nil?) ? nil : d[:total_kwh_consumed_high]-d[:total_kwh_produced_high]
+      net_consumed_low = (d[:total_kwh_consumed_low].nil? || d[:total_kwh_produced_low].nil?) ? nil : d[:total_kwh_consumed_low]-d[:total_kwh_produced_low]
+
+      return net_consumed_high, net_consumed_low
+    end  
     
     def diff_on(date)
       readings_on = day(date)
@@ -106,5 +123,22 @@ class Reading < ActiveRecord::Base
         { :total_kwh_consumed_high => 0, :total_kwh_consumed_low => 0, :total_kwh_produced_high => 0, :total_kwh_produced_low => 0, :total_m3_gas_consumed => 0 }
       end
     end
+
+    def diff_in_month(date)
+      hour_start = date.beginning_of_month.beginning_of_day
+      hour_end = date.end_of_month.end_of_day
+      # can't get cost for the future
+      hour_end = Time.now if hour_end > Time.now
+
+      readings_in_month =  Reading.where("created_at > :begin AND created_at < :end", { :begin => hour_start, :end => hour_end})  
+      last = readings_in_month.last
+      if last
+        last.diff(readings_in_month.first)
+      else
+        { :total_kwh_consumed_high => 0, :total_kwh_consumed_low => 0, :total_kwh_produced_high => 0, :total_kwh_produced_low => 0, :total_m3_gas_consumed => 0 }
+      end
+
+    end  
+
   end
 end