Add basic flow for adding email _or_ sms templates

Templates now have:
- a type (email or sms)
- a subject (if they are email templates)

We don’t want two completely separate view files for email and SMS, because they
would have an enormous amount of repetition.

So this commit adds
- different templates for SMS and email templates
- different form objects for SMS and email templates

…and wires them up.

app/main/views/templates.py

@@ -5,45 +5,44 @@ from notifications_python_client.errors import HTTPError
 from utils.template import Template
 
 from app.main import main
-from app.main.forms import TemplateForm
+from app.main.forms import SMSTemplateForm, EmailTemplateForm
 from app import job_api_client
-from app.main.dao.services_dao import get_service_by_id
+from app.main.dao.services_dao import get_service_by_id_or_404
 from app.main.dao import templates_dao as tdao
 from app.main.dao import services_dao as sdao
 
 
-@main.route("/services/<service_id>/templates")
+form_objects = {
+    'email': EmailTemplateForm,
+    'sms': SMSTemplateForm
+}
+
+
+@main.route("/services/<service_id>/templates/add-<template_type>", methods=['GET', 'POST'])
 @login_required
-def manage_service_templates(service_id):
-    return redirect(url_for(
-        '.choose_sms_template',
-        service_id=service_id
-    ))
+def add_service_template(service_id, template_type):
 
+    service = sdao.get_service_by_id_or_404(service_id)
 
-@main.route("/services/<service_id>/templates/add", methods=['GET', 'POST'])
-@login_required
-def add_service_template(service_id):
-    try:
-        service = sdao.get_service_by_id(service_id)['data']
-    except HTTPError as e:
-        if e.status_code == 404:
-            abort(404)
-        else:
-            raise e
+    if template_type not in ['sms', 'email']:
+        abort(404)
 
-    form = TemplateForm()
+    form = form_objects[template_type]()
 
     if form.validate_on_submit():
         tdao.insert_service_template(
-            form.name.data, form.template_content.data, service_id)
-        return redirect(url_for(
-            '.choose_sms_template', service_id=service_id))
+            form.name.data, form.template_content.data, service_id, form.subject.data or None
+        )
+        return redirect(
+            url_for('.choose_template', service_id=service_id, template_type=template_type)
+        )
+
     return render_template(
-        'views/edit-template.html',
-        h1='Add a text message template',
+        'views/edit-{}-template.html'.format(template_type),
         form=form,
-        service_id=service_id)
+        template_type=template_type,
+        service_id=service_id
+    )
 
 
 @main.route("/services/<service_id>/templates/<int:template_id>", methods=['GET', 'POST'])
@@ -51,20 +50,25 @@ def add_service_template(service_id):
 def edit_service_template(service_id, template_id):
     template = tdao.get_service_template_or_404(service_id, template_id)['data']
     template['template_content'] = template['content']
-    form = TemplateForm(**template)
+    form = form_objects[template['template_type']](**template)
 
     if form.validate_on_submit():
         tdao.update_service_template(
             template_id, form.name.data,
             form.template_content.data, service_id)
-        return redirect(url_for('.choose_sms_template', service_id=service_id))
+        return redirect(url_for(
+            '.choose_template',
+            service_id=service_id,
+            template_type=template['template_type']
+        ))
 
     return render_template(
-        'views/edit-template.html',
-        h1='Edit template',
+        'views/edit-{}-template.html'.format(template['template_type']),
         form=form,
         service_id=service_id,
-        template_id=template_id)
+        template_id=template_id,
+        template_type=template['template_type']
+    )
 
 
 @main.route("/services/<service_id>/templates/<int:template_id>/delete", methods=['GET', 'POST'])
@@ -74,13 +78,17 @@ def delete_service_template(service_id, template_id):
 
     if request.method == 'POST':
         tdao.delete_service_template(service_id, template_id)
-        return redirect(url_for('.manage_service_templates', service_id=service_id))
+        return redirect(url_for(
+            '.choose_template',
+            service_id=service_id,
+            template_type=template['template_type']
+        ))
 
     template['template_content'] = template['content']
-    form = TemplateForm(**template)
+    form = form_objects[template['template_type']](**template)
     flash('Are you sure you want to delete ‘{}’?'.format(form.name.data), 'delete')
     return render_template(
-        'views/edit-template.html',
+        'views/edit-{}-template.html'.format(template['template_type']),
         h1='Edit template',
         form=form,
         service_id=service_id,