feat(ProgressiveBilling) - Add historical_usage_amount_cents to LifetimeUsage

app/models/lifetime_usage.rb

@@ -10,6 +10,7 @@ class LifetimeUsage < ApplicationRecord
 
   validates :current_usage_amount_cents, numericality: {greater_than_or_equal_to: 0}
   validates :invoiced_usage_amount_cents, numericality: {greater_than_or_equal_to: 0}
+  validates :historical_usage_amount_cents, numericality: {greater_than_or_equal_to: 0}
 
   monetize :current_usage_amount_cents,
     :invoiced_usage_amount_cents,
@@ -28,6 +29,7 @@ class LifetimeUsage < ApplicationRecord
 #  current_usage_amount_cents         :bigint           default(0), not null
 #  current_usage_amount_refreshed_at  :datetime
 #  deleted_at                         :datetime
+#  historical_usage_amount_cents      :bigint           default(0), not null
 #  invoiced_usage_amount_cents        :bigint           default(0), not null
 #  invoiced_usage_amount_refreshed_at :datetime
 #  recalculate_current_usage          :boolean          default(FALSE), not null

app/services/lifetime_usages/usage_thresholds/check_service.rb

@@ -22,7 +22,7 @@ def call
         actual_current_usage = lifetime_usage.current_usage_amount_cents - progressive_billed_amount
         # we can end up in a situation where this goes below zero, in that case no thresholds are passed
         return result if actual_current_usage.negative?
-        invoiced_usage = lifetime_usage.invoiced_usage_amount_cents + progressive_billed_amount
+        invoiced_usage = lifetime_usage.historical_usage_amount_cents + lifetime_usage.invoiced_usage_amount_cents + progressive_billed_amount
 
         # Get the largest threshold amount
         # in case there are no fixed_thresholds, this will return nil which to_i will convert to 0

db/migrate/20240822080031_add_historical_usage_to_lifetime_usage.rb

@@ -0,0 +1,7 @@
+# frozen_string_literal: true
+
+class AddHistoricalUsageToLifetimeUsage < ActiveRecord::Migration[7.1]
+  def change
+    add_column :lifetime_usages, :historical_usage_amount_cents, :bigint, default: 0, null: false
+  end
+end

spec/models/lifetime_usage_spec.rb

@@ -32,6 +32,17 @@
       lifetime_usage.invoiced_usage_amount_cents = 1
       expect(lifetime_usage).to be_valid
     end
+
+    it 'requires that historical_usage_amount_cents is positive' do
+      lifetime_usage.historical_usage_amount_cents = -1
+      expect(lifetime_usage).not_to be_valid
+
+      lifetime_usage.historical_usage_amount_cents = 0
+      expect(lifetime_usage).to be_valid
+
+      lifetime_usage.historical_usage_amount_cents = 1
+      expect(lifetime_usage).to be_valid
+    end
   end
 
   describe ".needs_recalculation scope" do

spec/services/lifetime_usages/usage_thresholds/check_service_spec.rb

@@ -5,13 +5,14 @@
 RSpec.describe LifetimeUsages::UsageThresholds::CheckService, type: :service do
   subject(:service) { described_class.new(lifetime_usage:, progressive_billed_amount:) }
 
-  let(:lifetime_usage) { create(:lifetime_usage, subscription:, recalculate_current_usage:, recalculate_invoiced_usage:) }
+  let(:lifetime_usage) { create(:lifetime_usage, subscription:, historical_usage_amount_cents:, recalculate_current_usage:, recalculate_invoiced_usage:) }
   let(:progressive_billed_amount) { 0 }
   let(:recalculate_current_usage) { true }
   let(:recalculate_invoiced_usage) { true }
   let(:subscription) { create(:subscription, customer_id: customer.id) }
   let(:organization) { subscription.organization }
   let(:customer) { create(:customer) }
+  let(:historical_usage_amount_cents) { 0 }
 
   def create_thresholds(subscription, amounts:, recurring: nil)
     amounts.each do |amount|
@@ -294,4 +295,32 @@ def validate_thresholds(mapping)
       end
     end
   end
+
+  context "with historical_usage_amount_cents" do
+    let(:historical_usage_amount_cents) { 11 }
+
+    context "with multiple fixed thresholds" do
+      before do
+        create_thresholds(subscription, amounts: [10, 20, 31, 40])
+      end
+
+      it "calculates the passed thresholds correctly" do
+        validate_thresholds({
+          [0, 7] => [],
+          [0, 9] => [20],
+          [0, 10] => [20],
+          [9, 0] => [],
+          [0, 31] => [20, 31, 40],
+          [8, 2] => [20],
+          [8, 20] => [20, 31],
+          [8, 31] => [20, 31, 40],
+          [11, 1] => [],
+          [11, 10] => [31],
+          [21, 20] => [40],
+          [40, 2] => [],
+          [50, 0] => []
+        })
+      end
+    end
+  end
 end