a11y(champs): expose ids for UI on champ

app/helpers/application_helper.rb

@@ -50,7 +50,7 @@ module ApplicationHelper
   end
 
   def render_champ(champ)
-    champ_selector = ".editable-champ[data-champ-id=\"#{champ.id}\"]"
+    champ_selector = "##{champ.input_group_id}"
     form_html = render 'shared/dossiers/edit', dossier: champ.dossier, apercu: false
     champ_html = Nokogiri::HTML.fragment(form_html).at_css(champ_selector).to_s
     # rubocop:disable Rails/OutputSafety

app/helpers/champ_helper.rb

@@ -20,12 +20,6 @@ module ChampHelper
     simple_format(auto_linked_text, {}, sanitize: false)
   end
 
-  def describedby_id(champ)
-    if champ.description.present?
-      "desc-#{champ.type_de_champ.id}-#{champ.row}"
-    end
-  end
-
   def auto_attach_url(form, object)
     if object.is_a?(Champ) && object.persisted? && object.public?
       champs_piece_justificative_url(object.id)

app/models/champ.rb

@@ -139,6 +139,22 @@ class Champ < ApplicationRecord
     true
   end
 
+  def input_group_id
+    "champ-#{html_id}"
+  end
+
+  def input_id
+    "#{html_id}-input"
+  end
+
+  def labelledby_id
+    "#{html_id}-label"
+  end
+
+  def describedby_id
+    "#{html_id}-description" if description.present?
+  end
+
   def stable_id
     type_de_champ.stable_id
   end
@@ -159,6 +175,10 @@ class Champ < ApplicationRecord
 
   private
 
+  def html_id
+    "#{stable_id}-#{id}"
+  end
+
   def needs_dossier_id?
     !dossier_id && parent_id
   end