Add notification mails for teacher change by voucher redemption

app/controllers/concerns/notifier.rb

@@ -7,4 +7,18 @@ def notify_new_editor_by_mail(editor, lecture)
                             lecture: lecture)
                       .new_editor_email.deliver_later
   end
+
+  def notify_new_teacher_by_mail(teacher, lecture)
+    NotificationMailer.with(recipient: teacher,
+                            locale: teacher.locale,
+                            lecture: lecture)
+                      .new_teacher_email.deliver_later
+  end
+
+  def notify_previous_teacher_by_mail(previous_teacher, lecture)
+    NotificationMailer.with(recipient: previous_teacher,
+                            locale: previous_teacher.locale,
+                            lecture: lecture)
+                      .previous_teacher_email.deliver_later
+  end
 end

app/controllers/vouchers_controller.rb

@@ -49,7 +49,7 @@ def redeem
     if voucher
       lecture = voucher.lecture
       redemption = process_voucher(voucher, lecture)
-      redemption.create_notifications!
+      redemption&.create_notifications!
       redirect_to edit_profile_path, notice: success_message(voucher)
     else
       handle_invalid_voucher
@@ -111,9 +111,12 @@ def process_editor_voucher(voucher, lecture)
     end
 
     def process_teacher_voucher(voucher, lecture)
+      previous_teacher = lecture.teacher
       lecture.update_teacher_status!(current_user)
-      # notify_new_teacher_by_mail(current_user, lecture)
-      # notify_previous_teacher_by_mail(lecture)
+      if previous_teacher != current_user
+        notify_new_teacher_by_mail(current_user, lecture)
+        notify_previous_teacher_by_mail(previous_teacher, lecture)
+      end
       Redemption.create(user: current_user, voucher: voucher)
     end
 

app/mailers/notification_mailer.rb

@@ -62,6 +62,29 @@ def new_editor_email
                     title: @lecture.title_for_viewers))
   end
 
+  def new_teacher_email
+    @lecture = params[:lecture]
+    @recipient = params[:recipient]
+    @username = @recipient.tutorial_name
+
+    mail(from: @sender,
+         to: @recipient.email,
+         subject: t("mailer.new_teacher_subject",
+                    title: @lecture.title_for_viewers))
+  end
+
+  def previous_teacher_email
+    @lecture = params[:lecture]
+    @recipient = params[:recipient]
+    @username = @recipient.tutorial_name
+
+    mail(from: @sender,
+         to: @recipient.email,
+         subject: t("mailer.previous_teacher_subject",
+                    title: @lecture.title_for_viewers,
+                    new_teacher: @lecture.teacher.tutorial_name))
+  end
+
   def submission_invitation_email
     @recipient = params[:recipient]
     @assignment = params[:assignment]

app/views/notification_mailer/new_teacher_email.html.erb

@@ -0,0 +1,7 @@
+<%= t('mailer.new_teacher', title: @lecture.title_with_teacher, username: @username) %>
+<br>
+<p class="pt-2">
+  <%= link_to(t('notifications.edit_lecture'),
+              edit_lecture_url(@lecture),
+              class: 'btn btn-primary') %>
+</p>

app/views/notification_mailer/new_teacher_email.text.erb

@@ -0,0 +1 @@
+<%= t('mailer.new_teacher', title: @lecture.title_with_teacher, username: @username) %>

app/views/notification_mailer/previous_teacher_email.html.erb

@@ -0,0 +1,10 @@
+<%= t('mailer.previous_teacher',
+      title: @lecture.title_with_teacher,
+      username: @username,
+      new_teacher: @lecture.teacher.info) %>
+<br>
+<p class="pt-2">
+  <%= link_to(t('notifications.edit_lecture'),
+              edit_lecture_url(@lecture),
+              class: 'btn btn-primary') %>
+</p>

app/views/notification_mailer/previous_teacher_email.text.erb

@@ -0,0 +1,4 @@
+<%= t('mailer.previous_teacher',
+      title: @lecture.title_with_teacher,
+      username: @username,
+      new_teacher: @lecture.teacher.info) %>

config/locales/de.yml

@@ -3158,6 +3158,14 @@ de:
     text: 'Text'
     new_editor_subject: 'EditorInnenrechte für %{title}'
     new_editor: 'Hallo %{username}, Du hast soeben Bearbeitungsrechte für %{title} erhalten.'
+    new_teacher_subject: 'DozentInnenstatus für %{title}'
+    new_teacher: 'Hallo %{username}, Du hast soeben DozentInnenstatus für %{title} erhalten.'
+    previous_teacher_subject: 'DozentInnenwechsel in %{title}'
+    previous_teacher: >
+      Hallo %{username}, in der Veranstaltung %{title} gab es einen
+      DozentInnenwechsel. %{new_teacher} hat einen DozentInnengutschein eingelöst
+      und ist jetzt DozentIn. Du bist nicht mehr DozentIn in %{title}, sondern
+      stattdessen VeranstaltungseditorIn.
     new_lecture_subject: 'Neue Veranstaltung %{title}'
     new_lecture: 'Es wurde eine neue Veranstaltung angelegt: %{title}.'
     subscribe_lecture: >

config/locales/en.yml

@@ -2969,6 +2969,14 @@ en:
     text: 'Text'
     new_editor_subject: 'Editing Rights for %{title}'
     new_editor: 'Dear %{username}, you have been given editing rights for %{title}.'
+    new_teacher_subject: 'Teacher Status for %{title}'
+    new_teacher: 'Dear %{username}, you have been given teacher status for %{title}.'
+    previous_teacher_subject: 'Teacher Change for %{title}'
+    previous_teacher: >
+      Dear %{username}, ther has been a teacher change for %{title}.
+      %{new_teacher} has redeemed a teacher voucher and is now the teacher for
+      this event series. You are no longer teacher for %{title}, but
+      editor instead.
     new_lecture_subject: 'New event series %{title}'
     new_lecture: 'A new event series has been made available: %{title}.'
     subscribe_lecture: 'You can subscribe to it in your profile settings.'