Update controller and view to use new year group step

app/controllers/placements/schools/placements/build_controller.rb

@@ -33,9 +33,7 @@ def add_additional_subjects
   end
 
   def add_year_group
-    @placement = build_placement
-    year_groups_for_select
-    @placement.year_group = session.dig(:add_a_placement, "year_group")
+    @current_step = Placements::AddPlacement::Steps::YearGroup.new(school:, year_group:)
     @previous_step = previous_step(:add_year_group)
   end
 
@@ -63,14 +61,15 @@ def update
     when :check_your_answers
       subject = Subject.find(session.dig(:add_a_placement, "subject_id"))
       phase = session.dig(:add_a_placement, "phase")
-      @placement = Placements::Schools::Placements::Build::Placement.new(school:, phase:, subject:)
       mentor_step = Placements::AddPlacement::Steps::Mentors.new(school:, mentor_ids:)
-      @placement.assign_attributes mentor_step.wizard_attributes
+      year_group_step = Placements::AddPlacement::Steps::YearGroup.new(school:, year_group:)
+      @placement = Placements::Schools::Placements::Build::Placement.new(school:, phase:, subject:)
+
+      @placement.assign_attributes [mentor_step.wizard_attributes, year_group_step.wizard_attributes].inject(:merge)
       if subject.has_child_subjects?
         @placement.additional_subject_ids = additional_subject_ids
         @placement.build_additional_subjects(additional_subject_ids)
       end
-      @placement.year_group = session.dig(:add_a_placement, "year_group") if @placement.phase == "Primary"
       @placement.build_mentors(mentor_step.wizard_attributes[:mentor_ids])
       @placement.save!
 
@@ -119,14 +118,11 @@ def update
         render :add_additional_subjects and return
       end
     when :add_year_group
-      year_group = params.dig(:placements_schools_placements_build_placement, :year_group)
-      @placement = build_placement
-      @placement.year_group = year_group
+      @current_step = Placements::AddPlacement::Steps::YearGroup.new(school:, year_group: year_group_params)
 
-      if @placement.valid_year_group?
-        session[:add_a_placement][:year_group] = year_group
+      if @current_step.valid?
+        session[:add_a_placement][:year_group] = @current_step.year_group
       else
-        year_groups_for_select
         render :add_year_group and return
       end
     when :add_mentors
@@ -243,6 +239,10 @@ def mentor_ids
     @mentor_ids ||= session.dig(:add_a_placement, "mentor_ids")&.compact_blank
   end
 
+  def year_group
+    @year_group ||= session.dig(:add_a_placement, "year_group")
+  end
+
   def phase_params
     params.dig(:placements_schools_placements_build_placement, :phase)
   end
@@ -259,6 +259,10 @@ def mentor_ids_params
     params.dig(:placements_add_placement_steps_mentors, :mentor_ids).compact_blank
   end
 
+  def year_group_params
+    params.dig(:placements_add_placement_steps_year_group, :year_group)
+  end
+
   def authorize_placement
     authorize Placement.new(school:)
   end

app/models/placements/schools/placements/build/placement.rb

@@ -52,13 +52,6 @@ def valid_additional_subjects?
     end
   end
 
-  def valid_year_group?
-    return true if school.phase != "Primary" || year_group.present?
-
-    errors.add(:year_group, :invalid)
-    false
-  end
-
   def all_valid?
     valid_phase? && valid_subject? && valid_additional_subjects?
   end

app/views/placements/schools/placements/build/add_year_group.html.erb

@@ -1,25 +1,25 @@
-<% content_for :page_title, @placement.errors.any? ? t(".title_with_error") : t(".title") %>
-<%= render "placements/schools/primary_navigation", school: @school, current_navigation: :placements %>
+<% content_for :page_title, @current_step.errors.any? ? t(".title_with_error") : t(".title") %>
+<%= render "placements/schools/primary_navigation", school: @current_step.school, current_navigation: :placements %>
 
 <%= content_for(:before_content) do %>
   <%= govuk_back_link(href: @previous_step) %>
 <% end %>
 
 <div class="govuk-width-container">
-  <%= form_for(@placement, url: placements_school_placement_build_path(@school, id: :add_year_group), method: :put) do |f| %>
+  <%= form_for(@current_step, url: placements_school_placement_build_path(@current_step.school, id: :add_year_group), method: :put) do |f| %>
     <%= f.govuk_error_summary %>
 
     <div class="govuk-grid-row">
       <div class="govuk-grid-column-two-thirds">
         <span class="govuk-caption-l"><%= t(".add_placement") %></span>
-        <%= f.govuk_collection_radio_buttons :year_group, @year_groups_for_select, :value, :name, :description, legend: { size: "l", text: t(".year_group") } %>
+        <%= f.govuk_collection_radio_buttons :year_group, @current_step.year_groups_for_selection, :value, :name, :description, legend: { size: "l", text: t(".year_group") } %>
 
         <%= f.govuk_submit t(".continue") %>
       </div>
     </div>
   <% end %>
 
   <p class="govuk-body">
-    <%= govuk_link_to(t(".cancel"), placements_school_placements_path(@school), no_visited_state: true) %>
+    <%= govuk_link_to(t(".cancel"), placements_school_placements_path(@current_step.school), no_visited_state: true) %>
   </p>
 </div>

config/locales/en/placements/schools/placements.yml

@@ -12,8 +12,6 @@ en:
               invalid: Select an additional subject
             provider_id:
               invalid: Select a provider
-            year_group:
-              invalid: Select a year group
         placement:
           attributes:
             mentor_ids: