Split models to prevent circular imports

This commit is the first step to disentangling the models from the API
clients. With the models in the same folder as the API clients it makes
it hard to import the API clients within the model without getting a
circular import.

After this commit the user API clients still has this problem, but at
least the service API client doesn’t.

app/models/service.py

@@ -0,0 +1,157 @@
+from werkzeug.utils import cached_property
+
+from app.utils import get_default_sms_sender
+
+
+class Service():
+
+    ALLOWED_PROPERTIES = {
+        'active',
+        'contact_link',
+        'dvla_organisation',
+        'email_branding',
+        'email_from',
+        'id',
+        'inbound_api',
+        'letter_contact_block',
+        'letter_logo_filename',
+        'message_limit',
+        'name',
+        'organisation_type',
+        'permissions',
+        'postage',
+        'prefix_sms',
+        'research_mode',
+        'service_callback_api',
+    }
+
+    def __init__(self, _dict):
+        # in the case of a bad request current service may be `None`
+        self._dict = _dict or {}
+        if 'permissions' not in self._dict:
+            self.permissions = {'email', 'sms', 'letter'}
+
+    def __bool__(self):
+        return self._dict != {}
+
+    def __getattr__(self, attr):
+        if attr in self.ALLOWED_PROPERTIES:
+            return self._dict[attr]
+        raise AttributeError('`{}` is not a service attribute'.format(attr))
+
+    def __getitem__(self, attr):
+        raise NotImplementedError(
+            'Use current_service.{} instead of current_service[\'{}\']'.format(attr, attr)
+        )
+
+    def get(self, attr, default=None):
+        try:
+            return self._dict[attr]
+        except KeyError:
+            return default
+
+    @property
+    def trial_mode(self):
+        return self._dict['restricted']
+
+    def has_permission(self, permission):
+        return permission in self.permissions
+
+    @cached_property
+    def has_jobs(self):
+        # Can’t import at top-level because app isn’t yet initialised
+        from app import job_api_client
+        return job_api_client.has_jobs(self.id)
+
+    @cached_property
+    def has_team_members(self):
+        from app import user_api_client
+        return user_api_client.get_count_of_users_with_permission(
+            self.id, 'manage_service'
+        ) > 1
+
+    @cached_property
+    def templates(self):
+
+        from app import service_api_client
+
+        templates = service_api_client.get_service_templates(self.id)['data']
+
+        return [
+            template for template in templates
+            if template['template_type'] in self.available_template_types
+        ]
+
+    def templates_by_type(self, template_type):
+        return [
+            template for template in self.templates
+            if template_type in {'all', template['template_type']}
+        ]
+
+    @property
+    def available_template_types(self):
+        return [
+            channel for channel in ('email', 'sms', 'letter')
+            if self.has_permission(channel)
+        ]
+
+    @property
+    def has_templates(self):
+        return len(self.templates) > 0
+
+    @property
+    def has_multiple_template_types(self):
+        return len({
+            template['template_type'] for template in self.templates
+        }) > 1
+
+    @property
+    def has_email_templates(self):
+        return len(self.templates_by_type('email')) > 0
+
+    @property
+    def has_sms_templates(self):
+        return len(self.templates_by_type('sms')) > 0
+
+    @cached_property
+    def has_email_reply_to_address(self):
+        from app import service_api_client
+        return bool(service_api_client.get_reply_to_email_addresses(
+            self.id
+        ))
+
+    @property
+    def needs_to_add_email_reply_to_address(self):
+        return self.has_email_templates and not self.has_email_reply_to_address
+
+    @property
+    def shouldnt_use_govuk_as_sms_sender(self):
+        return self.organisation_type in {'local', 'nhs'}
+
+    @cached_property
+    def sms_sender_is_govuk(self):
+        from app import service_api_client
+        return get_default_sms_sender(
+            service_api_client.get_sms_senders(self.id)
+        ) in {'GOVUK', 'None'}
+
+    @property
+    def needs_to_change_sms_sender(self):
+        return all((
+            self.has_sms_templates,
+            self.shouldnt_use_govuk_as_sms_sender,
+            self.sms_sender_is_govuk,
+        ))
+
+    @property
+    def go_live_checklist_completed(self):
+        return all((
+            self.has_team_members,
+            self.has_templates,
+            not self.needs_to_add_email_reply_to_address,
+            not self.needs_to_change_sms_sender,
+        ))
+
+    @property
+    def go_live_checklist_completed_as_yes_no(self):
+        return 'Yes' if self.go_live_checklist_completed else 'No'