Redirect to correct endpoint based on state

If you refresh the page on a current broadcast while someone has
cancelled it you’ll see the wrong navigation item selected. This commit
adds redirects to take you to the correct endpoint in these edge cases.

app/main/views/broadcast.py

@@ -292,17 +292,39 @@ def view_broadcast(service_id, broadcast_message_id):
     )
     if broadcast_message.status == 'draft':
         abort(404)
+
+    if (
+        broadcast_message.status in {'completed', 'cancelled', 'rejected'}
+        and request.endpoint != 'main.view_previous_broadcast'
+    ):
+        return redirect(url_for(
+            '.view_previous_broadcast',
+            service_id=current_service.id,
+            broadcast_message_id=broadcast_message.id,
+        ))
+
+    if (
+        broadcast_message.status in {'broadcasting', 'pending-approval'}
+        and request.endpoint != 'main.view_current_broadcast'
+    ):
+        return redirect(url_for(
+            '.view_current_broadcast',
+            service_id=current_service.id,
+            broadcast_message_id=broadcast_message.id,
+        ))
+
+    back_link_endpoint = {
+        'main.view_current_broadcast': '.broadcast_dashboard',
+        'main.view_previous_broadcast': '.broadcast_dashboard_previous',
+    }[request.endpoint]
+
     return render_template(
         'views/broadcast/view-message.html',
         broadcast_message=broadcast_message,
-        back_link={
-            'main.view_current_broadcast': url_for(
-                '.broadcast_dashboard', service_id=current_service.id
-            ),
-            'main.view_previous_broadcast': url_for(
-                '.broadcast_dashboard_previous', service_id=current_service.id
-            ),
-        }[request.endpoint],
+        back_link=url_for(
+            back_link_endpoint,
+            service_id=current_service.id,
+        ),
     )
 
 

tests/app/main/views/test_broadcast.py

@@ -1036,8 +1036,8 @@ def test_start_broadcasting(
     )
 
 
-@pytest.mark.parametrize('extra_fields, expected_paragraphs', (
-    ({
+@pytest.mark.parametrize('endpoint, extra_fields, expected_paragraphs', (
+    ('.view_current_broadcast', {
         'status': 'broadcasting',
         'finishes_at': '2020-02-23T23:23:23.000000',
     }, [
@@ -1045,7 +1045,7 @@ def test_start_broadcasting(
         'Prepared by Alice and approved by Bob.',
         'Broadcasting stops tomorrow at 11:23pm.'
     ]),
-    ({
+    ('.view_previous_broadcast', {
         'status': 'broadcasting',
         'finishes_at': '2020-02-22T22:20:20.000000',  # 2 mins before now()
     }, [
@@ -1053,7 +1053,7 @@ def test_start_broadcasting(
         'Prepared by Alice and approved by Bob.',
         'Finished broadcasting today at 10:20pm.'
     ]),
-    ({
+    ('.view_previous_broadcast', {
         'status': 'completed',
         'finishes_at': '2020-02-21T21:21:21.000000',
     }, [
@@ -1061,7 +1061,7 @@ def test_start_broadcasting(
         'Prepared by Alice and approved by Bob.',
         'Finished broadcasting yesterday at 9:21pm.',
     ]),
-    ({
+    ('.view_previous_broadcast', {
         'status': 'cancelled',
         'cancelled_by_id': sample_uuid,
         'cancelled_at': '2020-02-21T21:21:21.000000',
@@ -1079,6 +1079,7 @@ def test_view_broadcast_message_page(
     active_user_with_permissions,
     mock_get_broadcast_template,
     fake_uuid,
+    endpoint,
     extra_fields,
     expected_paragraphs,
 ):
@@ -1103,7 +1104,7 @@ def test_view_broadcast_message_page(
     service_one['permissions'] += ['broadcast']
 
     page = client_request.get(
-        '.view_current_broadcast',
+        endpoint,
         service_id=SERVICE_ONE_ID,
         broadcast_message_id=fake_uuid,
     )
@@ -1113,6 +1114,74 @@ def test_view_broadcast_message_page(
     ] == expected_paragraphs
 
 
+@pytest.mark.parametrize('endpoint', (
+    '.view_current_broadcast',
+    '.view_previous_broadcast',
+))
+@pytest.mark.parametrize('status, expected_highlighted_navigation_item', (
+    (
+        'pending-approval',
+        'Current alerts',
+    ),
+    (
+        'broadcasting',
+        'Current alerts',
+    ),
+    (
+        'completed',
+        'Previous alerts',
+    ),
+    (
+        'cancelled',
+        'Previous alerts',
+    ),
+    (
+        'rejected',
+        'Previous alerts',
+    ),
+))
+@freeze_time('2020-02-22T22:22:22.000000')
+def test_view_broadcast_message_shows_correct_highlighted_navigation(
+    mocker,
+    client_request,
+    service_one,
+    active_user_with_permissions,
+    mock_get_broadcast_template,
+    fake_uuid,
+    endpoint,
+    status,
+    expected_highlighted_navigation_item,
+):
+    mocker.patch(
+        'app.broadcast_message_api_client.get_broadcast_message',
+        return_value=broadcast_message_json(
+            id_=fake_uuid,
+            service_id=SERVICE_ONE_ID,
+            template_id=fake_uuid,
+            created_by_id=fake_uuid,
+            approved_by_id=fake_uuid,
+            starts_at='2020-02-20T20:20:20.000000',
+            finishes_at='2021-12-21T21:21:21.000000',
+            cancelled_at='2021-01-01T01:01:01.000000',
+            status=status,
+        ),
+    )
+    service_one['permissions'] += ['broadcast']
+
+    page = client_request.get(
+        endpoint,
+        service_id=SERVICE_ONE_ID,
+        broadcast_message_id=fake_uuid,
+        _follow_redirects=True
+    )
+
+    assert normalize_spaces(
+        page.select_one('.navigation .selected').text
+    ) == (
+        expected_highlighted_navigation_item
+    )
+
+
 @freeze_time('2020-02-22T22:22:22.000000')
 def test_view_pending_broadcast(
     mocker,