Calculation for grouping rollups when max method is used

We have consumption blocks with set of metric rollups.
This set belongs to the tenant. When we do max on this set
we will get just max and it doesn't get max value for each VM.
It should take max value for each VM and then sum these
maxes.
Example: (VM1 and VM1 are in one tenant TI)
VM1: 2 Allocated Cores (Max)
VM2: 3 Allocated Cores (Max)
Report grouped  bytenant:
Tenant: 5 Allocated Cores (2 + 3 ) - is sum of maxes

And costs are derived from this values.

For avg: there is no such issue:
VM1: 2 Allocated Cores (Avg) (Cores 3 MetricRollups: 1, 2, 3)
VM2: 3 Allocated Cores (Avg)(Cores in 3 MetricRollups:2, 3, 4)
Report grouped  bytenant:
Tenant: 5 Allocated Cores (2.5)

(3 + 2) / 2 = 2.5
(1 + 2 + 3  + 2 + 3 + 4) = 2,5
It is same, AVG method don't have such issue.

app/models/chargeback/consumption_with_rollups.rb

@@ -41,6 +41,13 @@ def max(metric, sub_metric = nil)
       values.present? ? values.max : 0
     end
 
+    def sum_of_maxes_from_grouped_values(metric, sub_metric = nil)
+      return max(metric, sub_metric) if sub_metric
+      @grouped_values ||= {}
+      grouped_rollups = @rollups.group_by { |x| x.resource.id }
+      @grouped_values[metric] ||= grouped_rollups.map { |_, rollups| rollups.collect(&metric.to_sym).compact.max }.compact.sum
+    end
+
     def avg(metric, sub_metric = nil)
       metric_sum = values(metric, sub_metric).sum
       metric_sum / consumed_hours_in_interval

app/models/chargeback/consumption_without_rollups.rb

@@ -60,6 +60,7 @@ def current_value(metric, _sub_metric = nil)
     end
     alias avg current_value
     alias max current_value
+    alias sum_of_maxes_from_grouped_values current_value
     private :current_value
   end
 end

app/models/chargeback/report_options.rb

@@ -33,6 +33,7 @@ def method_for_allocated_metrics
         raise "Invalid method for allocated calculations #{method}"
       end
 
+      return :sum_of_maxes_from_grouped_values if method == :max && group_by_tenant?
       method
     end
 

spec/models/chargeback_vm_spec.rb

@@ -462,7 +462,7 @@ def subject_row_for_tenant(tenant)
           expect(subject_row_for_tenant(tenant_2).cpu_used_cost).to eq(2 * 50 * hourly_usage * monthly_used_rate)
 
           expect(subject_row_for_tenant(tenant_3).cpu_used_metric).to eq(2 * 50 * hourly_usage)
-          expect(subject_row_for_tenant(tenant_3).cpu_used_cost).to eq( 2 * 50 * hourly_usage * monthly_used_rate)
+          expect(subject_row_for_tenant(tenant_3).cpu_used_cost).to eq(2 * 50 * hourly_usage * monthly_used_rate)
 
           expect(subject_row_for_tenant(tenant_4).cpu_used_metric).to eq(2 * 50 * hourly_usage)
           expect(subject_row_for_tenant(tenant_4).cpu_used_cost).to eq(2 * 50 * hourly_usage * monthly_used_rate)
@@ -502,7 +502,7 @@ def subject_row_for_tenant(tenant)
             expect(subject_row_for_tenant(tenant_2).cpu_used_cost).to eq(hourly_usage * 2 * 50 * monthly_used_rate)
 
             expect(subject_row_for_tenant(tenant_3).cpu_used_metric).to eq(hourly_usage * 2 * 50)
-            expect(subject_row_for_tenant(tenant_3).cpu_used_cost).to eq(hourly_usage * 2 * 50* monthly_used_rate)
+            expect(subject_row_for_tenant(tenant_3).cpu_used_cost).to eq(hourly_usage * 2 * 50 * monthly_used_rate)
 
             expect(subject_row_for_tenant(tenant_4).cpu_used_metric).to eq(hourly_usage * 2 * 50)
             expect(subject_row_for_tenant(tenant_4).cpu_used_cost).to eq(hourly_usage * 2 * 50 * monthly_used_rate)
@@ -540,11 +540,11 @@ def result_row_for_vm(vm)
               expect(subject_row_for_tenant(tenant_1).cpu_used_cost).to eq(all_vms_cpu_cost)
 
               # Tenant 5 Vms
-              result_vm_1_5 = result_row_for_vm(vm_1_5)
-              result_vm_2_5 = result_row_for_vm(vm_2_5)
+              result_vm15 = result_row_for_vm(vm_1_5)
+              result_vm25 = result_row_for_vm(vm_2_5)
 
-              expect(subject_row_for_tenant(tenant_5).cpu_used_metric).to eq(result_vm_1_5.cpu_used_metric + result_vm_2_5.cpu_used_metric)
-              expect(subject_row_for_tenant(tenant_5).cpu_used_cost).to eq(result_vm_1_5.cpu_used_cost + result_vm_2_5.cpu_used_cost)
+              expect(subject_row_for_tenant(tenant_5).cpu_used_metric).to eq(result_vm15.cpu_used_metric + result_vm25.cpu_used_metric)
+              expect(subject_row_for_tenant(tenant_5).cpu_used_cost).to eq(result_vm15.cpu_used_cost + result_vm25.cpu_used_cost)
             end
 
             it 'calculated allocted metric and cost with using max(max is not summed up - it is taken maximum)' do