Preload the latest submission in the editor on the activity show page

app/assets/javascripts/exercise.ts

@@ -115,7 +115,7 @@ function initExerciseDescription(): void {
     centerImagesAndTables();
 }
 
-function initExerciseShow(exerciseId: number, programmingLanguage: string, loggedIn: boolean, editorShown: boolean, courseId: number, _deadline: string, baseSubmissionsUrl: string): void {
+function initExerciseShow(exerciseId: number, programmingLanguage: string, loggedIn: boolean, editorShown: boolean, courseId: number, _deadline: string, baseSubmissionsUrl: string, boilerplate: string): void {
     let editor: AceAjax.Editor;
     let lastSubmission: string;
     let lastTimeout: number;
@@ -126,6 +126,7 @@ function initExerciseShow(exerciseId: number, programmingLanguage: string, logge
             initDeadlineTimeout();
             enableSubmissionTableLinks();
             swapActionButtons();
+            initRestoreBoilerplateButton(boilerplate);
         }
 
         // submit source code if button is clicked on editor panel
@@ -430,6 +431,20 @@ function initExerciseShow(exerciseId: number, programmingLanguage: string, logge
         showDeadlineAlerts();
     }
 
+    function initRestoreBoilerplateButton(boilerplate: string): void {
+        const restoreWarning = document.getElementById("restore-boilerplate");
+        if (!restoreWarning) {
+            return;
+        }
+
+        const resetButton = restoreWarning.querySelector("a");
+        resetButton.addEventListener("click", () => {
+            editor.setValue(boilerplate);
+            editor.focus();
+            restoreWarning.hidden = true;
+        });
+    }
+
     init();
 }
 

app/assets/stylesheets/models/activities.css.scss

@@ -185,3 +185,9 @@ center img {
     padding-top: 0;
   }
 }
+
+#restore-boilerplate {
+  a {
+    cursor: pointer;
+  }
+}

app/controllers/activities_controller.rb

@@ -124,17 +124,20 @@ def show
       @submissions = @activity.submissions.includes(:annotations)
       @submissions = @submissions.in_course(@course) if @course.present? && current_user&.member_of?(@course)
       @submissions = @submissions.of_user(current_user) if current_user
-      @submissions = policy_scope(@submissions).paginate(page: parse_pagination_param(params[:page]))
+      @submissions = policy_scope(@submissions)
       if params[:edit_submission]
         @edit_submission = Submission.find(params[:edit_submission])
         authorize @edit_submission, :edit?
+      elsif @submissions.any?
+        @last_submission = @submissions.first
       end
+      @submissions = @submissions.paginate(page: parse_pagination_param(params[:page]))
       if params[:from_solution]
         @solution = @activity.solutions[params[:from_solution]]
         authorize @activity, :info?
       end
 
-      @code = @edit_submission.try(:code) || @solution || @activity.boilerplate
+      @code = @edit_submission.try(:code) || @solution || @last_submission.try(:code) || @activity.boilerplate
     elsif @activity.content_page?
       @read_state = if current_user&.member_of?(@course)
                       @activity.activity_read_states.find_by(user: current_user, course: @course)

app/views/activities/show.html.erb

@@ -114,6 +114,14 @@ end %>
                   <%= t('.deadline_passed', deadline: @series.deadline.today? ? @series.deadline.strftime('%R') : @series.deadline.strftime('%F %R')) %>
                 </div>
               <% end %>
+              <% if !@edit_submission && !@solution && @last_submission %>
+                <div class="alert alert-info" id="restore-boilerplate">
+                  <%= t ".preloaded_info" %>
+                  <a >
+                    <%= t(@activity.boilerplate ? ".preloaded_restore" : ".preloaded_clear") %>
+                  </a>
+                </div>
+              <% end %>
               <div id="editor-window" class='tex2jax_ignore'>
                 <div id="editor-text"><%= @code %></div>
               </div>
@@ -173,7 +181,8 @@ end %>
             <%= policy(@activity).submit? || !user_signed_in? %>,
             <%= @course&.id || "null" %>,
             <%= raw "\"#{@series&.deadline&.httpdate}\"" || "null" %>,
-            "<%= submissions_url %>"
+            "<%= submissions_url %>",
+            `<%= (@activity.exercise? && raw(@activity.boilerplate))|| "" %>`,
         );
     });
 </script>

config/locales/views/activities/en.yml

@@ -94,6 +94,9 @@ en:
         back_to_course_actionable: Go back to course
       mark_as_read: Mark as read
       read_at: "Marked as read on %{timestamp}"
+      preloaded_info: "We have preloaded your latest submission into the editor."
+      preloaded_clear: Clear editor.
+      preloaded_restore: Restore the boilerplate code.
     series_activities_add_table:
       course_added_to_usable: "Adding this exercise will allow this course to use all of the private exercises in this exercise's repository. Are you sure?"
     edit:

config/locales/views/activities/nl.yml

@@ -94,6 +94,9 @@ nl:
         back_to_course_actionable: Ga terug naar de cursus
       mark_as_read: Markeren als gelezen
       read_at: "Gelezen op %{timestamp}"
+      preloaded_info: We hebben jouw laatste oplossing ingeladen in de editor.
+      preloaded_clear: Maak de editor leeg.
+      preloaded_restore: Herstel de boilerplate-code.
     series_activities_add_table:
       course_added_to_usable: "Deze oefening toevoegen zal deze cursus toegang geven tot alle privé oefeningen in de repository van deze oefening. Ben je zeker?"
     edit: