feat(Instructeurs::Dossiers#next/prev): add route to redirect user from a dossier id to either a next dossier, either a previous

app/controllers/instructeurs/dossiers_controller.rb

@@ -390,8 +390,36 @@ module Instructeurs
       @pieces_jointes_seen_at = current_instructeur.follows.find_by(dossier: dossier)&.pieces_jointes_seen_at
     end
 
+    def next
+      navigate_throw_dossier_list do |cache|
+        cache.next_dossier_id(from_id: params[:dossier_id])
+      end
+    end
+
+    def previous
+      navigate_throw_dossier_list do |cache|
+        cache.previous_dossier_id(from_id: params[:dossier_id])
+      end
+    end
+
     private
 
+    def navigate_throw_dossier_list
+      dossier = dossier_scope.find(params[:dossier_id])
+      procedure_presentation = current_instructeur.procedure_presentation_for_procedure_id(dossier.procedure.id)
+      cache = Cache::ProcedureDossierPagination.new(procedure_presentation:, statut: params[:statut])
+
+      next_or_previous_dossier_id = yield(cache)
+
+      if next_or_previous_dossier_id
+        redirect_to instructeur_dossier_path(procedure_id: procedure.id, dossier_id: next_or_previous_dossier_id, statut: params[:statut])
+      else
+        redirect_back fallback_location: instructeur_dossier_path(procedure_id: procedure.id, dossier_id: dossier.id, statut: params[:statut]), alert: "Une erreur est survenue"
+      end
+    rescue ActiveRecord::RecordNotFound
+      redirect_to instructeur_procedure_path(procedure_id: procedure.id), alert: "Une erreur est survenue"
+    end
+
     def dossier_scope
       if action_name == 'update_annotations'
         Dossier

config/routes.rb

@@ -485,6 +485,8 @@ Rails.application.routes.draw do
           resources :dossiers, only: [:show, :destroy], param: :dossier_id, path: "(:statut)/dossiers", defaults: { statut: 'a-suivre' } do
             member do
               resources :commentaires, only: [:destroy]
+              get 'next'
+              get 'previous'
               post 'repousser-expiration' => 'dossiers#extend_conservation'
               post 'repousser-expiration-and-restore' => 'dossiers#extend_conservation_and_restore'
               post 'dossier_labels' => 'dossiers#dossier_labels'

spec/controllers/instructeurs/dossiers_controller_spec.rb

@@ -984,6 +984,68 @@ describe Instructeurs::DossiersController, type: :controller do
     end
   end
 
+  describe 'navigation accross next/prev dossiers' do
+    let(:dossier_id) { dossier.id }
+    let(:statut) { 'a-suivre' }
+    let(:previous_dossier) { create(:dossier, :en_construction, procedure:) }
+    let(:next_dossier) { create(:dossier, :en_construction, procedure:) }
+    let(:cached_ids) { [previous_dossier, dossier, next_dossier].map(&:id) }
+    before do
+      cache = Cache::ProcedureDossierPagination.new(procedure_presentation: double(procedure:, instructeur:), statut:)
+      cache.save_context(incoming_page: 1, ids: cached_ids)
+    end
+
+    context 'when nexting' do
+      subject { get :next, params: { procedure_id: procedure.id, dossier_id: from_id, statut: } }
+
+      context 'when their is a next id' do
+        let(:from_id) { dossier.id }
+        it { is_expected.to redirect_to(instructeur_dossier_path(procedure_id: procedure.id, dossier_id: next_dossier.id)) }
+      end
+
+      context 'when their is not next id (en of list)' do
+        let(:from_id) { cached_ids.last }
+        it 'redirect on fallback location being current dossier and flashes an error' do
+          expect(subject).to redirect_to(instructeur_dossier_path(procedure_id: procedure.id, dossier_id: from_id))
+          expect(flash.alert).to eq("Une erreur est survenue")
+        end
+      end
+
+      context 'when id does not exists' do
+        let(:from_id) { 'kthxbye' }
+        it 'redirect on fallback location being current dossier and flashes an error' do
+          expect(subject).to redirect_to(instructeur_procedure_path(procedure_id: procedure.id))
+          expect(flash.alert).to eq("Une erreur est survenue")
+        end
+      end
+    end
+
+    context 'when previousing' do
+      subject { get :previous, params: { procedure_id: procedure.id, dossier_id: from_id, statut: } }
+
+      context 'when their is a previous id' do
+        let(:from_id) { dossier.id }
+        it { is_expected.to redirect_to(instructeur_dossier_path(procedure_id: procedure.id, dossier_id: previous_dossier.id)) }
+      end
+
+      context 'when their is not previous id (before list)' do
+        let(:from_id) { cached_ids.first }
+        it 'redirect on fallback location being current dossier and flashes an error' do
+          expect(subject).to redirect_to(instructeur_dossier_path(procedure_id: procedure.id, dossier_id: from_id))
+          expect(flash.alert).to eq("Une erreur est survenue")
+        end
+      end
+
+      context 'when id does not exists' do
+        let(:from_id) { 'kthxbye' }
+        it 'redirect on fallback location being current dossier and flashes an error' do
+          expect(subject).to redirect_to(instructeur_procedure_path(procedure_id: procedure.id))
+          expect(flash.alert).to eq("Une erreur est survenue")
+        end
+      end
+    end
+  end
+
   describe "#update_annotations" do
     let(:procedure) do
       create(:procedure, :published, types_de_champ_public:, types_de_champ_private:, instructeurs: instructeurs)