Do not charge for hours that are yet to come

For variable_rate, we charge only that much that has been consumed.

Perhaps I'll end the service tmrw, I should not be charged in advanced.

https://bugzilla.redhat.com/show_bug.cgi?id=1402072

app/models/chargeback/consumption.rb

@@ -4,8 +4,12 @@ def initialize(start_time, end_time)
       @start_time, @end_time = start_time, end_time
     end
 
-    def hours_in_interval
-      @hours_in_interval ||= (@end_time - @start_time).round / 1.hour
+    def past_hours_in_interval
+      # We cannot charge for future hours (i.e. weekly report on Monday, should charge just monday)
+      @past_hours_in_interval ||= begin
+                                    past = (Time.current - @start_time).round / 1.hour
+                                    [past, hours_in_interval].min
+                                  end
     end
 
     def hours_in_month
@@ -16,6 +20,10 @@ def hours_in_month
 
     private
 
+    def hours_in_interval
+      @hours_in_interval ||= (@end_time - @start_time).round / 1.hour
+    end
+
     def monthly?
       # A heuristic. Is the interval lenght about 30 days?
       (hours_in_interval * 1.hour - 1.month).abs < 3.days

app/models/chargeback/consumption_with_rollups.rb

@@ -19,7 +19,7 @@ def max(metric)
 
     def avg(metric)
       metric_sum = values(metric).sum
-      metric_sum / hours_in_interval
+      metric_sum / past_hours_in_interval
     end
 
     def none?(metric)

app/models/chargeback_rate_detail.rb

@@ -233,7 +233,7 @@ def cost_keys
 
   def metric_and_cost_by(consumption)
     metric_value = metric_value_by(consumption)
-    [metric_value, hourly_cost(metric_value, consumption) * consumption.hours_in_interval]
+    [metric_value, hourly_cost(metric_value, consumption) * consumption.past_hours_in_interval]
   end
 
   def first_tier?(tier,tiers)