Add button to approve broadcast

Since new broadcasts will go into `pending-approval`, we now need a way
of approving them.

This commit adds a button to this page to start (or approve) the
broadcast. This button is wrapped in a bordered box, to emphasise that
it’s something consequential.

app/assets/stylesheets/components/banner.scss

@@ -24,6 +24,10 @@
     @include copy-19;
   }
 
+  .page-footer {
+    margin-bottom: govuk-spacing(1);
+  }
+
 }
 
 %banner-with-tick,

app/main/views/broadcast.py

@@ -169,6 +169,32 @@ def view_broadcast_message(service_id, broadcast_message_id):
     )
 
 
+@main.route('/services/<uuid:service_id>/broadcast/<uuid:broadcast_message_id>', methods=['POST'])
+@user_has_permissions('send_messages')
+@service_has_permission('broadcast')
+def approve_broadcast_message(service_id, broadcast_message_id):
+
+    broadcast_message = BroadcastMessage.from_id(
+        broadcast_message_id,
+        service_id=current_service.id,
+    )
+
+    if broadcast_message.status != 'pending-approval':
+        return redirect(url_for(
+            '.view_broadcast_message',
+            service_id=current_service.id,
+            broadcast_message_id=broadcast_message.id,
+        ))
+
+    broadcast_message.approve_broadcast()
+
+    return redirect(url_for(
+        '.view_broadcast_message',
+        service_id=current_service.id,
+        broadcast_message_id=broadcast_message.id,
+    ))
+
+
 @main.route('/services/<uuid:service_id>/broadcast/<uuid:broadcast_message_id>/cancel')
 @user_has_permissions('send_messages')
 @service_has_permission('broadcast')

app/models/broadcast_message.py

@@ -138,6 +138,12 @@ class BroadcastMessage(JSONModel):
         )
         self._set_status_to('pending-approval')
 
+    def approve_broadcast(self):
+        self._update(
+            starts_at=datetime.utcnow().isoformat(),
+        )
+        self._set_status_to('broadcasting')
+
     def cancel_broadcast(self):
         self._set_status_to('cancelled')
 

app/navigation.py

@@ -361,6 +361,7 @@ class HeaderNavigation(Navigation):
         'remove_broadcast_area',
         'preview_broadcast_message',
         'view_broadcast_message',
+        'approve_broadcast_message',
         'cancel_broadcast_message',
     }
 
@@ -419,6 +420,7 @@ class MainNavigation(Navigation):
             'remove_broadcast_area',
             'preview_broadcast_message',
             'view_broadcast_message',
+            'approve_broadcast_message',
             'cancel_broadcast_message',
         },
         'uploads': {
@@ -1012,6 +1014,7 @@ class CaseworkNavigation(Navigation):
         'remove_broadcast_area',
         'preview_broadcast_message',
         'view_broadcast_message',
+        'approve_broadcast_message',
         'cancel_broadcast_message',
     }
 
@@ -1333,5 +1336,6 @@ class OrgNavigation(Navigation):
         'remove_broadcast_area',
         'preview_broadcast_message',
         'view_broadcast_message',
+        'approve_broadcast_message',
         'cancel_broadcast_message',
     }

app/templates/views/broadcast/view-message.html

@@ -1,7 +1,7 @@
 {% from "components/button/macro.njk" import govukButton %}
 {% from "components/form.html" import form_wrapper %}
 {% from "components/page-header.html" import page_header %}
-{% from "components/page-footer.html" import sticky_page_footer %}
+{% from "components/page-footer.html" import page_footer %}
 
 {% extends "withnav_template.html" %}
 
@@ -17,10 +17,15 @@
   ) }}
 
   {% if broadcast_message.status == 'pending-approval' %}
-    <p class="govuk-body govuk-!-margin-bottom-3">
-      {{ broadcast_message.created_by.name }} wants to broadcast this
-      message until {{ broadcast_message.finishes_at|format_datetime_relative }}.
-    </p>
+    {% call form_wrapper(class="banner govuk-!-margin-bottom-6") %}
+      <p class="govuk-body govuk-!-margin-top-0 govuk-!-margin-bottom-3">
+        {{ broadcast_message.created_by.name }} wants to broadcast this
+        message until {{ broadcast_message.finishes_at|format_datetime_relative }}.
+      </p>
+      {{ page_footer(
+        "Start broadcasting now"
+      ) }}
+    {% endcall %}
   {% else %}
     <p class="govuk-body govuk-!-margin-bottom-3">
       Created by {{ broadcast_message.created_by.name }} and approved by