add back button link on completed logs

app/views/logs/edit.html.erb

@@ -12,9 +12,11 @@
 
     <% if @log.status == "in_progress" %>
       <p class="govuk-body govuk-!-margin-bottom-7"><%= get_subsections_count(@log, :completed) %> of <%= get_subsections_count(@log) %> subsections completed.</p>
+
       <p class="govuk-body govuk-!-margin-bottom-2">
         <% next_incomplete_section = get_next_incomplete_section(@log) %>
       </p>
+
       <p>
         <% if next_incomplete_section.present? %>
           <a class="app-section-skip-link" href="#<%= next_incomplete_section.id.dasherize %>">
@@ -28,10 +30,20 @@
       <p class="govuk-body">
         <%= status_tag(@log.status) %>
       </p>
+
       <p class="govuk-body">
         <%= review_log_text(@log) %>
       </p>
     <% end %>
+
     <%= render "tasklist" %>
+
+    <% if @log.completed? %>
+      <% if @log.lettings? %>
+        <%= govuk_button_link_to "Back to lettings logs", lettings_logs_path %>
+      <% else %>
+        <%= govuk_button_link_to "Back to sales logs", sales_logs_path %>
+      <% end %>
+    <% end %>
   </div>
 </div>

spec/views/logs/edit.html.erb_spec.rb

@@ -0,0 +1,45 @@
+require "rails_helper"
+
+RSpec.describe "logs/edit.html.erb" do
+  before do
+    assign(:log, log)
+  end
+
+  context "when log is in progress" do
+    let(:log) { create(:lettings_log, :in_progress) }
+
+    it "there is no link back to log type root" do
+      render
+
+      fragment = Capybara::Node::Simple.new(rendered)
+
+      expect(fragment).not_to have_link(text: "Back to lettings logs", href: "/lettings-logs")
+    end
+  end
+
+  context "when log is completed" do
+    context "when showing a lettings log" do
+      let(:log) { create(:lettings_log, :completed) }
+
+      it "has link 'Back to lettings logs'" do
+        render
+
+        fragment = Capybara::Node::Simple.new(rendered)
+
+        expect(fragment).to have_link(text: "Back to lettings logs", href: "/lettings-logs")
+      end
+    end
+
+    context "when showing a sales log" do
+      let(:log) { create(:sales_log, :completed) }
+
+      it "has link 'Back to sales logs'" do
+        render
+
+        fragment = Capybara::Node::Simple.new(rendered)
+
+        expect(fragment).to have_link(text: "Back to sales logs", href: "/sales-logs")
+      end
+    end
+  end
+end