Fix code working with nil values

app/assets/javascripts/components/saved_annotations/saved_annotation_list.ts

@@ -73,8 +73,12 @@ export class SavedAnnotationList extends DodonaElement {
                                     <a href="${sa.url}">${sa.title}</a>
                                 </td>
                                 <td class="ellipsis-overflow" title="${sa.annotation_text}">${sa.annotation_text}</td>
-                                <td><d-filter-button param="course_id" value="${sa.course.id}">${sa.course.name}</td></td>
-                                <td><d-filter-button param="exercise_id" value="${sa.exercise.id}">${sa.exercise.name}</td></td>
+                                <td>
+                                    ${sa.course ? html`<d-filter-button param="course_id" value="${sa.course.id}">${sa.course.name}</d-filter-button>` : ""}
+                                </td>
+                                <td>
+                                    ${sa.exercise ? html`<d-filter-button param="exercise_id" value="${sa.exercise.id}">${sa.exercise.name}</d-filter-button>` : ""}
+                                </td>
                             </tr>
                         `)}
                     </tbody>

app/models/saved_annotation.rb

@@ -24,8 +24,8 @@ class SavedAnnotation < ApplicationRecord
   has_many :submissions, through: :annotations
 
   scope :by_user, ->(user_id) { where user_id: user_id }
-  scope :by_course, ->(course_id) { where course_id: course_id }
-  scope :by_exercise, ->(exercise_id) { where exercise_id: exercise_id }
+  scope :by_course, ->(course_id) { where(course_id: course_id).or(where(course_id: nil)) }
+  scope :by_exercise, ->(exercise_id) { where(exercise_id: exercise_id).or(where(exercise_id: nil)) }
   scope :by_filter, ->(filter) { where 'title LIKE ? or annotation_text LIKE ?', "%#{filter}%", "%#{filter}%" }
 
   scope :order_by_annotations_count, ->(direction) { reorder(annotations_count: direction) }

app/views/saved_annotations/index.json.jbuilder

@@ -6,14 +6,18 @@ json.array! @saved_annotations do |saved_annotation|
     json.url user_url(saved_annotation.user)
     json.id saved_annotation.user.id
   end
-  json.exercise do
-    json.name saved_annotation.exercise.name
-    json.url activity_url(saved_annotation.exercise)
-    json.id saved_annotation.exercise.id
+  if saved_annotation.exercise.present?
+    json.exercise do
+      json.name saved_annotation.exercise.name
+      json.url activity_url(saved_annotation.exercise)
+      json.id saved_annotation.exercise.id
+    end
   end
-  json.course do
-    json.name saved_annotation.course.name
-    json.url course_url(saved_annotation.course)
-    json.id saved_annotation.course.id
+  if saved_annotation.course.present?
+    json.course do
+      json.name saved_annotation.course.name
+      json.url course_url(saved_annotation.course)
+      json.id saved_annotation.course.id
+    end
   end
 end

app/views/saved_annotations/show.html.erb

@@ -12,12 +12,19 @@
       <div class="card-supporting-text">
         <p><strong><%= @saved_annotation.title %></strong></p>
         <blockquote><%= markdown @saved_annotation.annotation_text %></blockquote>
-        <%= t ".usage_info_html",
-          exercise_path: course_activity_path(@saved_annotation.course ,@saved_annotation.exercise),
-          exercise_name: @saved_annotation.exercise.name,
-          course_path: course_path(@saved_annotation.course),
-          course_name: @saved_annotation.course.name
-         %><br/>
+        <%= t ".usage_info" %>
+        <% if @saved_annotation.exercise.present?  %>
+          <%= t ".exercise_info_html",
+            exercise_path: activity_scoped_path(activity: @saved_annotation.exercise, course: @saved_annotation.course),
+            exercise_name: @saved_annotation.exercise.name
+           %>
+        <% end %>
+        <% if @saved_annotation.course.present?  %>
+          <%= t ".course_info_html",
+            course_path: course_path(@saved_annotation.course),
+            course_name: @saved_annotation.course.name
+           %>
+        <% end %><br/>
         <%= t ".count_info_html", count: @saved_annotation.annotations_count %>
       </div>
       <div class="card-supporting-text card-border">

config/locales/views/saved_annotations/en.yml

@@ -4,7 +4,9 @@ en:
       title: Saved comments
     show:
       linked_submissions: Linked submissions
-      usage_info_html: This comment can be reused on all submissions for the exercise <a href="%{exercise_path}">%{exercise_name}</a> in the course <a href="%{course_path}">%{course_name}</a>.
+      usage_info: This comment can be reused on all submissions
+      exercise_info_html: for the exercise <a href="%{exercise_path}">%{exercise_name}</a>
+      course_info_html: in the course <a href="%{course_path}">%{course_name}</a>
       count_info_html: This comment is used %{count} times.
     edit:
       title: Edit saved comment

config/locales/views/saved_annotations/nl.yml

@@ -4,7 +4,9 @@ nl:
       title: Opgeslagen opmerkingen
     show:
       linked_submissions: Gekoppelde oplossingen
-      usage_info_html: Deze opmerking kan worden hergebruikt op alle ingediende oplossingen voor de oefening <a href="%{exercise_path}">%{exercise_name}</a> in de cursus <a href="%{course_path}">%{course_name}</a>.
+      usage_info: Deze opmerking kan worden hergebruikt op alle ingediende oplossingen
+      exercise_info_html: voor de oefening <a href="%{exercise_path}">%{exercise_name}</a>
+      course_info_html: in de cursus <a href="%{course_path}">%{course_name}</a>
       count_info_html: Deze opmerking wordt <strong>%{count}</strong> keer gebruikt.
     edit:
       title: Bewerk opgeslagen opmerking

db/migrate/20240626093130_allow_null_for_saved_annotation_exercise_and_course.rb

@@ -0,0 +1,6 @@
+class AllowNullForSavedAnnotationExerciseAndCourse < ActiveRecord::Migration[7.1]
+  def change
+    change_column_null :saved_annotations, :exercise_id, true
+    change_column_null :saved_annotations, :course_id, true
+  end
+end