From 81bd54116a8d6d078a22d20df19aedbbc5cf3177 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Timoth=C3=A9e=20Floure?= <timothee.floure@posteo.net>
Date: Mon, 2 Mar 2020 09:25:03 +0100
Subject: [PATCH] Add records to orders

---
 uncloud/uncloud_pay/models.py      | 28 +++++++++++++++-------------
 uncloud/uncloud_pay/serializers.py |  9 ++++++++-
 uncloud/uncloud_vm/models.py       |  6 ++++--
 uncloud/uncloud_vm/views.py        |  7 +++++++
 4 files changed, 34 insertions(+), 16 deletions(-)

diff --git a/uncloud/uncloud_pay/models.py b/uncloud/uncloud_pay/models.py
index 2862940..8b19c37 100644
--- a/uncloud/uncloud_pay/models.py
+++ b/uncloud/uncloud_pay/models.py
@@ -65,16 +65,6 @@ class BillEntry():
 # confusing: the order is a 'contract' with the customer, were both parts
 # agree on deal => That's what we want to keep archived.
 #
-# SOON:
-#
-# We'll need to add some kind of OrderEntry table (each order might have
-# multiple entries) storing: recurring_price, recurring_period, setup_fee, description
-#
-# FOR NOW:
-#
-# We dynamically get pricing from linked product, as they are not updated in
-# this stage of development.
-#
 # /!\ BIG FAT WARNING /!\ #
 class Order(models.Model):
     uuid = models.UUIDField(primary_key=True, default=uuid.uuid4, editable=False)
@@ -95,11 +85,23 @@ class Order(models.Model):
                               choices = RecurringPeriod.choices,
                               default = RecurringPeriod.PER_MONTH)
 
+    @property
+    def records(self):
+        return OrderRecord.objects.filter(order=self)
 
     @property
-    def amount(self):
-        records = OrderRecord.objects.filter(order=self)
-        return 1
+    def setup_fee(self):
+        return reduce(lambda acc, record: acc + record.setup_fee, self.records, 0)
+
+    @property
+    def recurring_price(self):
+        return reduce(lambda acc, record: acc + record.recurring_price, self.records, 0)
+
+    def add_record(self, setup_fee, recurring_price, description):
+        OrderRecord.objects.create(order=self,
+                setup_fee=setup_fee,
+                recurring_price=recurring_price,
+                description=description)
 
 class OrderRecord(models.Model):
     order = models.ForeignKey(Order, on_delete=models.CASCADE)
diff --git a/uncloud/uncloud_pay/serializers.py b/uncloud/uncloud_pay/serializers.py
index eeab444..83eebb6 100644
--- a/uncloud/uncloud_pay/serializers.py
+++ b/uncloud/uncloud_pay/serializers.py
@@ -26,10 +26,17 @@ class PaymentMethodSerializer(serializers.ModelSerializer):
 class ProductSerializer(serializers.Serializer):
     vms = VMProductSerializer(many=True, read_only=True)
 
+class OrderRecordSerializer(serializers.ModelSerializer):
+    class Meta:
+        model = OrderRecord
+        fields  = ['setup_fee', 'recurring_price', 'description']
+
 class OrderSerializer(serializers.ModelSerializer):
+    records = OrderRecordSerializer(many=True, read_only=True)
     class Meta:
         model = Order
-        fields = '__all__'
+        fields = ['uuid', 'creation_date', 'starting_date', 'ending_date',
+                'bill', 'recurring_period', 'records', 'recurring_price', 'setup_fee']
 
 class UserSerializer(serializers.ModelSerializer):
     class Meta:
diff --git a/uncloud/uncloud_vm/models.py b/uncloud/uncloud_vm/models.py
index be1178e..c32f3a5 100644
--- a/uncloud/uncloud_vm/models.py
+++ b/uncloud/uncloud_vm/models.py
@@ -40,8 +40,6 @@ class VMProduct(Product):
                                  blank=True,
                                  null=True)
 
-    description = "Virtual Machine"
-
     # VM-specific. The name is only intended for customers: it's a pain te
     # remember IDs (speaking from experience as ungleich customer)!
     name = models.CharField(max_length=32)
@@ -55,6 +53,10 @@ class VMProduct(Product):
         else:
             raise Exception('Invalid recurring period for VM Product pricing.')
 
+    @property
+    def description(self):
+        return "Virtual machine '{}': {} core(s), {}GB memory".format(
+                self.name, self.cores, self.ram_in_gb)
 
 class VMWithOSProduct(VMProduct):
     pass
diff --git a/uncloud/uncloud_vm/views.py b/uncloud/uncloud_vm/views.py
index 2dec2ae..5eeec7b 100644
--- a/uncloud/uncloud_vm/views.py
+++ b/uncloud/uncloud_vm/views.py
@@ -28,6 +28,9 @@ class VMProductViewSet(ProductViewSet):
         return VMProduct.objects.filter(owner=self.request.user)
 
     def create(self, request):
+        # TODO: what if something blows-up midway?
+        # => need a transaction
+
         # Create base order.
         order = Order.objects.create(
                 recurring_period=RecurringPeriod.PER_MONTH,
@@ -40,6 +43,10 @@ class VMProductViewSet(ProductViewSet):
         serializer.is_valid(raise_exception=True)
         vm = serializer.save(owner=request.user, order=order)
 
+        # Add Product record to order (VM is mutable, allows to keep history in order).
+        order.add_record(vm.setup_fee,
+                vm.recurring_price(order.recurring_period), vm.description)
+
         return Response(serializer.data)