Associating billable periods with the relevant adjustment, and moving labelling logic to model

app/jobs/update_user_invoices.rb

@@ -40,38 +40,13 @@ class UpdateUserInvoices
       })
     else
       billable_periods.reject{ |bp| bp.turnover == 0 }.each do |billable_period|
-        adjustment = invoice.adjustments.where(source_id: billable_period).first
-        adjustment ||= invoice.adjustments.new( adjustment_attrs_from(billable_period), :without_protection => true)
-        adjustment.update_attributes( label: adjustment_label_from(billable_period), amount: billable_period.bill )
-        current_adjustments << adjustment
+        current_adjustments << billable_period.ensure_correct_adjustment_for(invoice)
       end
     end
 
     clean_up_and_save(invoice, current_adjustments)
   end
 
-  def adjustment_attrs_from(billable_period)
-    # We should ultimately have an EnterprisePackage model, which holds all info about shop type, producer, trials, etc.
-    # It should also implement a calculator that we can use here by specifying the package as the originator of the
-    # adjustment, meaning that adjustments are created and updated using Spree's existing architecture.
-
-    { source: billable_period,
-      originator: nil,
-      mandatory: true,
-      locked: false
-    }
-  end
-
-  def adjustment_label_from(billable_period)
-    enterprise = billable_period.enterprise.version_at(billable_period.begins_at)
-    category = enterprise.category.to_s.titleize
-    category += (billable_period.trial ? " Trial" : "")
-    begins = billable_period.begins_at.localtime.strftime("%d/%m/%y")
-    ends = billable_period.ends_at.localtime.strftime("%d/%m/%y")
-
-    "#{enterprise.name} (#{category}) [#{begins} - #{ends}]"
-  end
-
   def clean_up_and_save(invoice, current_adjustments)
     # Snag and then delete any obsolete adjustments
     obsolete_adjustments = invoice.adjustments.where('source_type = (?) AND id NOT IN (?)', "BillablePeriod", current_adjustments)

app/models/billable_period.rb

@@ -1,5 +1,6 @@
 class BillablePeriod < ActiveRecord::Base
   belongs_to :enterprise
+  has_one :adjustment, :as => :source, class_name: "Spree::Adjustment" #, :dependent => :destroy
   belongs_to :owner, class_name: 'Spree::User', foreign_key: :owner_id
 
   default_scope where(deleted_at: nil)
@@ -23,7 +24,50 @@ class BillablePeriod < ActiveRecord::Base
     end
   end
 
+  def adjustment_label
+    enterprise_version = enterprise.version_at(begins_at)
+    category = enterprise_version.category.to_s.titleize
+    category += (trial ? " Trial" : "")
+    begins = begins_at.localtime.strftime("%d/%m/%y")
+    ends = ends_at.localtime.strftime("%d/%m/%y")
+
+    "#{enterprise_version.name} (#{category}) [#{begins} - #{ends}]"
+  end
+
   def delete
     self.update_column(:deleted_at, Time.now)
   end
+
+  def ensure_correct_adjustment_for(invoice)
+    if adjustment
+      # adjustment.originator = enterprise.package
+      adjustment.update_attributes( label: adjustment_label, amount: bill )
+    else
+      self.adjustment = invoice.adjustments.new( adjustment_attrs, :without_protection => true )
+    end
+
+    if Spree::Config.account_bill_inc_tax
+      adjustment.set_included_tax! Spree::Config.account_bill_tax_rate
+    else
+      adjustment.set_included_tax! 0
+    end
+
+    adjustment
+  end
+
+  private
+
+  def adjustment_attrs
+    # We should ultimately have an EnterprisePackage model, which holds all info about shop type, producer, trials, etc.
+    # It should also implement a calculator that we can use here by specifying the package as the originator of the
+    # adjustment, meaning that adjustments are created and updated using Spree's existing architecture.
+
+    { label: adjustment_label,
+      amount: bill,
+      source: self,
+      originator: nil, # enterprise.package
+      mandatory: true,
+      locked: false
+    }
+  end
 end

spec/jobs/update_user_invoices_spec.rb

@@ -104,7 +104,7 @@ describe UpdateUserInvoices do
         travel_to(3.hours)
 
         before do
-          allow(updater).to receive(:adjustment_label_from).exactly(1).times.and_return("Old Item")
+          allow(old_billable_period).to receive(:adjustment_label) { "Old Item" }
           allow(old_billable_period).to receive(:bill) { 666.66 }
         end
 
@@ -159,7 +159,8 @@ describe UpdateUserInvoices do
         travel_to(20.days)
 
         before do
-          allow(updater).to receive(:adjustment_label_from).exactly(2).times.and_return("BP1 Item", "BP2 Item")
+          allow(billable_period1).to receive(:adjustment_label) { "BP1 Item" }
+          allow(billable_period2).to receive(:adjustment_label) { "BP2 Item" }
           allow(billable_period1).to receive(:bill) { 123.45 }
           allow(billable_period2).to receive(:bill) { 543.21 }
         end

spec/models/billable_period_spec.rb

@@ -0,0 +1,27 @@
+require 'spec_helper'
+
+describe Customer, type: :model do
+  describe 'ensure_correct_adjustment' do
+    let!(:start_of_july) { Time.now.beginning_of_year + 6.months }
+    let!(:user) { create(:user) }
+    let!(:invoice) { create(:order, user: user) }
+    let!(:billable_period) { create(:billable_period, owner: user, begins_at: start_of_july, ends_at: start_of_july + 12.days) }
+
+    before do
+      allow(billable_period).to receive(:bill) { 99 }
+      allow(billable_period).to receive(:adjustment_label) { "Label for adjustment" }
+      Spree::Config.set({ account_bill_inc_tax: true })
+      Spree::Config.set({ account_bill_tax_rate: 0.1 })
+    end
+
+    context "when no adjustment currently exists" do
+      it "creates an adjustment on the given order" do
+        expect(invoice.total_tax).to eq 0.0
+        expect(billable_period.adjustment).to be nil
+        billable_period.ensure_correct_adjustment_for(invoice)
+        expect(billable_period.adjustment).to be_a Spree::Adjustment
+        expect(invoice.total_tax).to eq 9.0
+      end
+    end
+  end
+end