feat(demarche): describe procedure prefilling (#8187)

* feat(demarche): description

Show the description of an opendata procedure (published or draft),
with help about how to prefill a dossier for this procedure.

Co-authored-by: Damien Le Thiec <damien.lethiec@gmail.com>

spec/models/prefill_description_spec.rb

@@ -0,0 +1,79 @@
+RSpec.describe PrefillDescription, type: :model do
+  include Rails.application.routes.url_helpers
+
+  describe '#update' do
+    let(:prefill_description) { described_class.new(build(:procedure)) }
+    let(:selected_type_de_champ_ids) { ["1", "2"] }
+    subject(:update) { prefill_description.update(attributes) }
+
+    context 'when selected_type_de_champ_ids are given' do
+      let(:attributes) { { selected_type_de_champ_ids: selected_type_de_champ_ids } }
+
+      it 'populate selected_type_de_champ_ids' do
+        expect { update }.to change { prefill_description.selected_type_de_champ_ids }.from([]).to(selected_type_de_champ_ids)
+      end
+    end
+  end
+
+  describe '#types_de_champ' do
+    let(:procedure) { create(:procedure) }
+    let(:type_de_champ) { create(:type_de_champ_text, procedure: procedure) }
+    let(:prefill_description) { described_class.new(procedure) }
+
+    it { expect(prefill_description.types_de_champ).to match([type_de_champ]) }
+  end
+
+  describe '#include?' do
+    let(:prefill_description) { described_class.new(build(:procedure)) }
+    let(:type_de_champ_id) { 1 }
+    subject(:included) { prefill_description.include?(type_de_champ_id) }
+
+    context 'when the id has been added to the prefill_description' do
+      before { prefill_description.update(selected_type_de_champ_ids: ["1"]) }
+
+      it { expect(included).to eq(true) }
+    end
+
+    context 'when the id has not be added to the prefill_description' do
+      it { expect(included).to eq(false) }
+    end
+  end
+
+  describe '#link_too_long?' do
+    let(:procedure) { create(:procedure) }
+    let(:prefill_description) { described_class.new(procedure) }
+
+    subject(:too_long) { prefill_description.link_too_long? }
+
+    before { prefill_description.update(selected_type_de_champ_ids: create_list(:type_de_champ_text, type_de_champs_count, procedure: procedure).map(&:id)) }
+
+    context 'when the prefill link is too long' do
+      let(:type_de_champs_count) { 60 }
+
+      it { expect(too_long).to eq(true) }
+    end
+
+    context 'when the prefill link is not too long' do
+      let(:type_de_champs_count) { 2 }
+
+      it { expect(too_long).to eq(false) }
+    end
+  end
+
+  describe '#prefill_link' do
+    let(:procedure) { create(:procedure) }
+    let(:type_de_champ) { create(:type_de_champ_text, procedure: procedure) }
+    let(:prefill_description) { described_class.new(procedure) }
+
+    before { prefill_description.update(selected_type_de_champ_ids: [type_de_champ.id]) }
+
+    it "builds the URL to create a new prefilled dossier" do
+      expect(prefill_description.prefill_link).to eq(
+        commencer_url(
+          path: procedure.path,
+          "champ_#{type_de_champ.to_typed_id}" => type_de_champ.libelle
+        )
+      )
+    end
+  end
+end