reopen can transition to a class

app/interactors/transition_authorization_request_to_previous_stage.rb

@@ -0,0 +1,20 @@
+class TransitionAuthorizationRequestToPreviousStage < ApplicationInteractor
+  def call
+    return if context.authorization_request_class.blank?
+
+    context.fail! unless context.authorization_request.can_reopen_to_class?(context.authorization_request_class)
+
+    return if context.authorization_request.is_a? context.authorization_request_class
+
+    transition_to_previous_stage
+  end
+
+  private
+
+  def transition_to_previous_stage
+    context.authorization_request.update!(
+      type: context.authorization_request_class.to_s,
+      form_uid: context.authorization_request.definition.previous_stage_form(context.authorization_request_class).id
+    )
+  end
+end

app/models/authorization_request.rb

@@ -96,7 +96,11 @@ def latest_authorization_of_class(authorization_request_class)
   end
 
   def available_classes_for_reopen
-    authorizations.distinct.pluck(:authorization_request_class)
+    authorizations.distinct.pluck(:authorization_request_class).map(&:constantize)
+  end
+
+  def can_reopen_to_class?(authorization_request_class)
+    available_classes_for_reopen.include? authorization_request_class
   end
 
   def events

app/organizers/reopen_authorization.rb

@@ -5,5 +5,5 @@ class ReopenAuthorization < ApplicationOrganizer
     context.authorization_request = context.authorization.request
   end
 
-  organize ExecuteAuthorizationRequestTransitionWithCallbacks
+  organize TransitionAuthorizationRequestToPreviousStage, ExecuteAuthorizationRequestTransitionWithCallbacks
 end

spec/organizers/reopen_authorization_spec.rb

@@ -36,5 +36,38 @@
         expect { reopen_authorization_request }.not_to change { authorization_request.reload.state }
       end
     end
+
+    context 'with an authorization_request_class to transition to' do
+      subject(:reopen_authorization_request) { described_class.call(authorization:, user:, authorization_request_class:) }
+
+      let(:authorization_request) { create(:authorization_request, :api_impot_particulier, :validated) }
+      let(:authorization_request_class) { AuthorizationRequest::APIImpotParticulierSandbox }
+
+      it 'transitions the authorization request to a previous stage' do
+        expect { reopen_authorization_request }.to change { AuthorizationRequest.find(authorization_request.id).class }.from(AuthorizationRequest::APIImpotParticulier).to(AuthorizationRequest::APIImpotParticulierSandbox)
+      end
+
+      it "transistions the authorization request's form to the previous stage's form" do
+        expect { reopen_authorization_request }.to change { AuthorizationRequest.find(authorization_request.id).form_uid }.from('api-impot-particulier-production').to('api-impot-particulier-sandbox')
+      end
+
+      context 'when the authorization_request_class is from the same stage' do
+        let(:authorization_request_class) { AuthorizationRequest::APIImpotParticulier }
+
+        it "doesn't transitions the authorization_request class" do
+          expect { reopen_authorization_request }.not_to change { AuthorizationRequest.find(authorization_request.id).class }
+        end
+
+        it "doesn't transitions the authorization_request form" do
+          expect { reopen_authorization_request }.not_to change { AuthorizationRequest.find(authorization_request.id).form_uid }
+        end
+      end
+
+      context 'when the authorization_request_class is not an available reopen class' do
+        let(:authorization_request_class) { AuthorizationRequest::APIHermes }
+
+        it { is_expected.to be_failure }
+      end
+    end
   end
 end