Introduce candidate to wrong email address page

app/controllers/candidate_interface/errors_controller.rb

@@ -2,6 +2,7 @@ module CandidateInterface
   class ErrorsController < CandidateInterfaceController
     skip_before_action :verify_authenticity_token
     skip_before_action :authenticate_candidate!
+    allow_unauthenticated_access only: [:wrong_email_address]
 
     def account_locked
       render 'errors/account_locked', status: :forbidden, formats: :html
@@ -10,5 +11,9 @@ def account_locked
     def not_found
       render 'errors/not_found', status: :not_found, formats: :html
     end
+
+    def wrong_email_address
+      render 'errors/wrong_email_address_used_for_candidate', status: :forbidden, formats: :html
+    end
   end
 end

app/controllers/one_login_controller.rb

@@ -74,7 +74,7 @@ def sign_out
   def sign_out_complete
     if session[:session_error_id].present?
       reset_session
-      redirect_to internal_server_error_path
+      redirect_to candidate_interface_wrong_email_address_path
     else
       redirect_to candidate_interface_create_account_or_sign_in_path
     end

app/views/errors/wrong_email_address_used_for_candidate.html.erb

@@ -0,0 +1,23 @@
+<%= content_for :title, t('page_titles.there_is_a_problem') %>
+
+<div class="govuk-grid-row">
+  <div class="govuk-grid-column-two-thirds">
+    <h1 class="govuk-heading-l"><%= t('page_titles.there_is_a_problem') %></h1>
+    <div class="govuk-body">
+      <%= t(
+        '.body_html',
+        button_link: render(
+          ButtonToAsLinkComponent.new(
+            name: t('.sign_in'),
+            path: OneLogin.bypass? ? '/auth/one-login-developer' : '/auth/one_login',
+          ),
+        ),
+      ) %>
+    </div>
+
+    <p class="govuk-body">
+      If you have any questions, please email us at
+      <%= govuk_mail_to '[email protected]' %>
+    </p>
+  </div>
+</div>

config/locales/candidate_interface/errors.yml

@@ -0,0 +1,5 @@
+en:
+  errors:
+    wrong_email_address_used_for_candidate:
+      body_html: You should use the email address you use for GOV.UK One Login to %{button_link}.
+      sign_in: sign in to Apply for teacher training

config/locales/en.yml

@@ -102,6 +102,7 @@ en:
     get_your_details_back: Get your details back
     dismiss: Dismiss
   page_titles:
+    there_is_a_problem: There is a problem
     account_recovery: Enter the code we sent to %{email}
     account_recovery_resend_email: Enter the new code we sent to %{email}
     account_recovery_request: Get your account details back

config/routes/candidate.rb

@@ -608,6 +608,7 @@
   end
 
   get '/account-locked', to: 'errors#account_locked'
+  get '/wrong-email-address', to: 'errors#wrong_email_address'
 
   get '/about-the-teacher-training-application-process', to: 'guidance#index', as: :guidance
 

spec/requests/one_login_controller_spec.rb

@@ -199,7 +199,7 @@
           "One login session error, check session_error record #{SessionError.last.id}",
           level: :error,
         )
-        expect(response).to redirect_to(internal_server_error_path)
+        expect(response).to redirect_to(candidate_interface_wrong_email_address_path)
       end
     end