feat(revshare): self billed invoice creation and skip payments (#3067)

## Roadmap

👉 https://getlago.canny.io/feature-requests/p/calculate-revenue-share

 ## Context

Current problem: companies with **partners** selling for them cannot
have a **revenue share** system in Lago.

We want to propose **self-billing** into Lago, a billing arrangement
where the **customer** creates and issues the invoice on **behalf** of
the **supplier** for goods or services received.

 ## Description

expose self_billed attribute in v1 invoices serializer

create invoice as self_billed when customer is a partner

skip payment creation for self_billed invoices.

app/serializers/v1/invoice_serializer.rb

@@ -27,6 +27,7 @@ def serialize
         prepaid_credit_amount_cents: model.prepaid_credit_amount_cents,
         file_url: model.file_url,
         version_number: model.version_number,
+        self_billed: model.self_billed,
         created_at: model.created_at.iso8601,
         updated_at: model.updated_at.iso8601
       }

app/services/invoices/create_generating_service.rb

@@ -27,7 +27,8 @@ def call
           issuing_date:,
           payment_due_date:,
           net_payment_term: customer.applicable_net_payment_term,
-          skip_charges:
+          skip_charges:,
+          self_billed: customer.partner_account?
         )
         result.invoice = invoice
 

app/services/invoices/payments/create_service.rb

@@ -97,6 +97,7 @@ def provider
       end
 
       def should_process_payment?
+        return false if invoice.self_billed?
         return false if invoice.payment_succeeded? || invoice.voided?
         return false if current_payment_provider.blank?
 

spec/factories/invoices.rb

@@ -56,5 +56,9 @@
         end
       end
     end
+
+    trait :self_billed do
+      self_billed { true }
+    end
   end
 end

spec/serializers/v1/invoice_serializer_spec.rb

@@ -53,6 +53,7 @@
           }
         ],
         "version_number" => 4,
+        "self_billed" => invoice.self_billed,
         "created_at" => invoice.created_at.iso8601,
         "updated_at" => invoice.updated_at.iso8601
       )

spec/services/invoices/create_generating_service_spec.rb

@@ -118,5 +118,15 @@
         end
       end
     end
+
+    context "when customer is a partner account" do
+      let(:customer) { create(:customer, account_type: "partner") }
+
+      it "creates an invoice with self billed" do
+        result = create_service.call
+
+        expect(result.invoice.self_billed).to eq(true)
+      end
+    end
   end
 end

spec/services/invoices/payments/create_service_spec.rb

@@ -97,6 +97,21 @@
       end
     end
 
+    context "when invoice is self_billed" do
+      let(:invoice) do
+        create(:invoice, :self_billed, customer:, organization:, total_amount_cents: 100)
+      end
+
+      it "does not creates a payment" do
+        result = create_service.call
+
+        expect(result).to be_success
+        expect(result.invoice).to eq(invoice)
+        expect(result.payment).to be_nil
+        expect(provider_class).not_to have_received(:new)
+      end
+    end
+
     context "when invoice is payment_succeeded" do
       before { invoice.payment_succeeded! }