From 9e9018060efac5e6536965222d44dd5a02e876fd Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Timoth=C3=A9e=20Floure?= <timothee.floure@posteo.net>
Date: Mon, 2 Mar 2020 10:46:04 +0100
Subject: [PATCH] Wire order records to bills, fix user balance

---
 uncloud/uncloud_pay/helpers.py     | 13 +++++----
 uncloud/uncloud_pay/models.py      | 44 ++++++++++++++++++++----------
 uncloud/uncloud_pay/serializers.py | 10 ++++++-
 3 files changed, 46 insertions(+), 21 deletions(-)

diff --git a/uncloud/uncloud_pay/helpers.py b/uncloud/uncloud_pay/helpers.py
index 9f775b7..b4216f6 100644
--- a/uncloud/uncloud_pay/helpers.py
+++ b/uncloud/uncloud_pay/helpers.py
@@ -8,12 +8,15 @@ from django.utils import timezone
 from django.core.exceptions import ObjectDoesNotExist
 from calendar import monthrange
 
-def sum_amounts(entries):
-    return reduce(lambda acc, entry: acc + entry.amount, entries, 0)
-
 def get_balance_for(user):
-    bills = sum_amounts(Bill.objects.filter(owner=user))
-    payments = sum_amounts(Payment.objects.filter(owner=user))
+    bills = reduce(
+            lambda acc, entry: acc + entry.total,
+            Bill.objects.filter(owner=user),
+            0)
+    payments = reduce(
+            lambda acc, entry: acc + entry.amount,
+            Payment.objects.filter(owner=user),
+            0)
     return payments - bills
 
 def get_payment_method_for(user):
diff --git a/uncloud/uncloud_pay/models.py b/uncloud/uncloud_pay/models.py
index 8b19c37..e257b9e 100644
--- a/uncloud/uncloud_pay/models.py
+++ b/uncloud/uncloud_pay/models.py
@@ -33,26 +33,40 @@ class Bill(models.Model):
     valid = models.BooleanField(default=True)
 
     @property
-    def entries(self):
-        # TODO: return list of Bill entries, extract from linked order
-        # for each related order
-        #   for each product
-        #       build BillEntry
-        return []
+    def records(self):
+        bill_records = []
+        orders = Order.objects.filter(bill=self)
+        for order in orders:
+            for order_record in order.records:
+                bill_record = BillRecord(
+                        self,
+                        order_record.setup_fee,
+                        order_record.recurring_price,
+                        order_record.recurring_period,
+                        order_record.description)
+                bill_records.append(bill_record)
+
+        return bill_records
 
     @property
     def total(self):
-        orders = Order.objects.filter(bill=self)
-        return reduce(lambda acc, order: acc + order.amount, orders, 0)
+        return reduce(lambda acc, record: acc + record.amount(), self.records, 0)
 
-class BillEntry():
-    start_date = timezone.now()
-    end_date = timezone.now()
-    recurring_period = RecurringPeriod.PER_MONTH
-    recurring_price = 0
-    amount = 0
-    description = ""
+class BillRecord():
+    def __init__(self, bill, setup_fee, recurring_price, recurring_period, description):
+        self.bill = bill
+        self.setup_fee = setup_fee
+        self.recurring_price = recurring_price
+        self.recurring_period = recurring_period
+        self.description = description
 
+    def amount(self):
+        # TODO: Billing logic here!
+        if self.recurring_period == RecurringPeriod.PER_MONTH:
+            return self.recurring_price # TODO
+        else:
+            raise Exception('Unsupported recurring period: {}.'.
+                    format(record.recurring_period))
 
 # /!\ BIG FAT WARNING /!\ #
 #
diff --git a/uncloud/uncloud_pay/serializers.py b/uncloud/uncloud_pay/serializers.py
index 83eebb6..976ab6b 100644
--- a/uncloud/uncloud_pay/serializers.py
+++ b/uncloud/uncloud_pay/serializers.py
@@ -7,11 +7,19 @@ from functools import reduce
 from uncloud_vm.serializers import VMProductSerializer
 from uncloud_vm.models import VMProduct
 
+# TODO: remove magic numbers for decimal fields
+class BillRecordSerializer(serializers.Serializer):
+    description = serializers.CharField()
+    recurring_period = serializers.CharField()
+    recurring_price = serializers.DecimalField(max_digits=10, decimal_places=2)
+    amount = serializers.DecimalField(max_digits=10, decimal_places=2)
+
 class BillSerializer(serializers.ModelSerializer):
+    records = BillRecordSerializer(many=True, read_only=True)
     class Meta:
         model = Bill
         fields = ['owner', 'total', 'due_date', 'creation_date',
-                'starting_date', 'ending_date']
+                'starting_date', 'ending_date', 'records']
 
 class PaymentSerializer(serializers.ModelSerializer):
     class Meta: