Refactor settings page to use service model

There’s a lot of code in service settings which:
- talks to the API directly through the clients
- passes that information through to the Jinja template

By encapsulating this logic in the service model:
- the Jinja template can access the data directly
- the logic can be reused across multiple methods

app/models/service.py

@@ -1,6 +1,11 @@
+from notifications_utils.field import Field
 from werkzeug.utils import cached_property
 
+from app.notify_client.billing_api_client import billing_api_client
+from app.notify_client.email_branding_client import email_branding_client
+from app.notify_client.inbound_number_client import inbound_number_client
 from app.notify_client.job_api_client import job_api_client
+from app.notify_client.organisations_api_client import organisations_client
 from app.notify_client.service_api_client import service_api_client
 from app.notify_client.user_api_client import user_api_client
 from app.utils import get_default_sms_sender
@@ -114,10 +119,28 @@ class Service():
         return len(self.templates_by_type('sms')) > 0
 
     @cached_property
+    def email_reply_to_addresses(self):
+        return service_api_client.get_reply_to_email_addresses(self.id)
+
+    @property
     def has_email_reply_to_address(self):
-        return bool(service_api_client.get_reply_to_email_addresses(
-            self.id
-        ))
+        return bool(self.email_reply_to_addresses)
+
+    @property
+    def count_email_reply_to_addresses(self):
+        return len(self.email_reply_to_addresses)
+
+    @property
+    def default_email_reply_to_address(self):
+        return next(
+            (
+                x['email_address']
+                for x in self.email_reply_to_addresses if x['is_default']
+            ), None
+        )
+
+    def get_email_reply_to_address(self, id):
+        return service_api_client.get_reply_to_email_address(self.id, id)
 
     @property
     def needs_to_add_email_reply_to_address(self):
@@ -128,10 +151,38 @@ class Service():
         return self.organisation_type in {'local', 'nhs'}
 
     @cached_property
+    def sms_senders(self):
+        return service_api_client.get_sms_senders(self.id)
+
+    @property
+    def sms_senders_with_hints(self):
+
+        def attach_hint(sender):
+            hints = []
+            if sender['is_default']:
+                hints += ["default"]
+            if sender['inbound_number_id']:
+                hints += ["receives replies"]
+            if hints:
+                sender['hint'] = "(" + " and ".join(hints) + ")"
+            return sender
+
+        return [attach_hint(sender) for sender in self.sms_senders]
+
+    @property
+    def default_sms_sender(self):
+        return get_default_sms_sender(self.sms_senders)
+
+    @property
+    def count_sms_senders(self):
+        return len(self.sms_senders)
+
+    @property
     def sms_sender_is_govuk(self):
-        return get_default_sms_sender(
-            service_api_client.get_sms_senders(self.id)
-        ) in {'GOVUK', 'None'}
+        return self.default_sms_sender in {'GOVUK', 'None'}
+
+    def get_sms_sender(self, id):
+        return service_api_client.get_sms_sender(self.id, id)
 
     @property
     def needs_to_change_sms_sender(self):
@@ -141,6 +192,26 @@ class Service():
             self.sms_sender_is_govuk,
         ))
 
+    @cached_property
+    def letter_contact_details(self):
+        return service_api_client.get_letter_contacts(self.id)
+
+    @property
+    def count_letter_contact_details(self):
+        return len(self.letter_contact_details)
+
+    @property
+    def default_letter_contact_block(self):
+        return next(
+            (
+                Field(x['contact_block'], html='escape')
+                for x in self.letter_contact_details if x['is_default']
+            ), None
+        )
+
+    def get_letter_contact_block(self, id):
+        return service_api_client.get_letter_contact(self.id, id)
+
     @property
     def go_live_checklist_completed(self):
         return all((
@@ -153,3 +224,42 @@ class Service():
     @property
     def go_live_checklist_completed_as_yes_no(self):
         return 'Yes' if self.go_live_checklist_completed else 'No'
+
+    @cached_property
+    def free_sms_fragment_limit(self):
+        return billing_api_client.get_free_sms_fragment_limit_for_year(self.id) or 0
+
+    @cached_property
+    def data_retention(self):
+        return service_api_client.get_service_data_retention(self.id)
+
+    def get_data_retention_item(self, id):
+        return service_api_client.get_service_data_retention_by_id(self.id, id)
+
+    @property
+    def email_branding_id(self):
+        return self._dict['email_branding']
+
+    @cached_property
+    def email_branding(self):
+        if self.email_branding_id:
+            return email_branding_client.get_email_branding(self.email_branding_id)['email_branding']
+        return None
+
+    @cached_property
+    def letter_branding(self):
+        return email_branding_client.get_letter_email_branding().get(
+            self.dvla_organisation, '001'
+        )
+
+    @cached_property
+    def organisation_name(self):
+        return organisations_client.get_service_organisation(self.id).get('name', None)
+
+    @cached_property
+    def inbound_number(self):
+        return inbound_number_client.get_inbound_sms_number_for_service(self.id)['data'].get('number', '')
+
+    @property
+    def has_inbound_number(self):
+        return bool(self.inbound_number)