Add link to cancel letters

Added a link to cancel letters from the letter notification pages if the
letter is still able to be cancelled. Clicking on this link will show a
confirmation box, and will then cancel the letter if the user confirms.

app/assets/stylesheets/components/stick-at-top-when-scrolling.scss

@@ -51,6 +51,10 @@
     min-height: 50px;
   }
 
+  .page-footer-delete-link-without-button {
+    margin-top: 10px;
+  }
+
   .notification-status {
     margin: 0;
   }

app/main/views/notifications.py

@@ -8,7 +8,9 @@ from dateutil import parser
 from flask import (
     Response,
     abort,
+    flash,
     jsonify,
+    redirect,
     render_template,
     request,
     stream_with_context,
@@ -83,6 +85,11 @@ def view_notification(service_id, notification_id):
 
     letter_print_day = get_letter_printing_statement(notification['status'], notification['created_at'])
 
+    notification_created = parser.parse(notification['created_at']).replace(tzinfo=None)
+
+    show_cancel_button = notification['notification_type'] == 'letter' and \
+        letter_can_be_cancelled(notification['status'], notification_created)
+
     return render_template(
         'views/notifications/notification.html',
         finished=(notification['status'] in (DELIVERED_STATUSES + FAILURE_STATUSES)),
@@ -110,10 +117,24 @@ def view_notification(service_id, notification_id):
         postage=notification['postage'],
         can_receive_inbound=(current_service.has_permission('inbound_sms')),
         is_precompiled_letter=notification['template']['is_precompiled_letter'],
-        letter_print_day=letter_print_day
+        letter_print_day=letter_print_day,
+        show_cancel_button=show_cancel_button
     )
 
 
+@main.route("/services/<service_id>/notification/<uuid:notification_id>/cancel", methods=['GET', 'POST'])
+@login_required
+@user_has_permissions('view_activity', 'send_messages')
+def cancel_letter(service_id, notification_id):
+
+    if request.method == 'POST':
+        notification_api_client.update_notification_to_cancelled(current_service.id, notification_id)
+        return redirect(url_for('main.view_notification', service_id=service_id, notification_id=notification_id))
+
+    flash("Are you sure you want to cancel sending this letter?", 'cancel')
+    return view_notification(service_id, notification_id)
+
+
 def get_letter_printing_statement(status, created_at):
     created_at_dt = parser.parse(created_at).replace(tzinfo=None)
 

app/navigation.py

@@ -121,6 +121,7 @@ class HeaderNavigation(Navigation):
         'cancel_invited_org_user',
         'cancel_invited_user',
         'cancel_job',
+        'cancel_letter',
         'check_and_resend_text_code',
         'check_and_resend_verification_code',
         'check_messages',
@@ -397,6 +398,7 @@ class MainNavigation(Navigation):
         'cancel_invited_org_user',
         'cancel_invited_user',
         'cancel_job',
+        'cancel_letter',
         'check_and_resend_text_code',
         'check_and_resend_verification_code',
         'check_messages_preview',
@@ -569,6 +571,7 @@ class CaseworkNavigation(Navigation):
         'cancel_invited_org_user',
         'cancel_invited_user',
         'cancel_job',
+        'cancel_letter',
         'check_and_resend_text_code',
         'check_and_resend_verification_code',
         'check_messages',
@@ -806,6 +809,7 @@ class OrgNavigation(Navigation):
         'cancel_invited_org_user',
         'cancel_invited_user',
         'cancel_job',
+        'cancel_letter',
         'check_and_resend_text_code',
         'check_and_resend_verification_code',
         'check_messages',

app/templates/flash_messages.html

@@ -6,7 +6,7 @@
         {{ banner(
           message if message is string else message[0],
           'default' if ((category == 'default') or (category == 'default_with_tick')) else 'dangerous',
-          delete_button="Yes, {}".format(category) if category in ['delete', 'suspend', 'resume', 'remove', 'revoke this API key'] else None,
+          delete_button="Yes, {}".format(category) if category in ['cancel', 'delete', 'suspend', 'resume', 'remove', 'revoke this API key'] else None,
           with_tick=True if category == 'default_with_tick' else False,
           context=message[1] if message is not string
         )}}

app/templates/views/notifications/notification.html

@@ -64,7 +64,13 @@
     {% if template.template_type == 'letter' %}
       <div class="js-stick-at-bottom-when-scrolling">
         <div class="page-footer">
-          <div>&nbsp;</div>
+          {% if show_cancel_button %}
+            <span class="page-footer-delete-link page-footer-delete-link-without-button">
+              <a href="{{ url_for('main.cancel_letter', service_id=current_service.id, notification_id=notification_id) }}">Cancel sending this letter</a>
+            </span>
+          {% else %}
+            <div>&nbsp;</div>
+          {% endif %}
           <a class="page-footer-right-aligned-link" href="{{ url_for('main.view_letter_notification_as_preview', service_id=current_service.id, notification_id=notification_id, filetype='pdf') }}" download>Download as a PDF</a>
         </div>
       </div>