From 0e0374b5772197ce56a1d532db2efa914ef5e56a Mon Sep 17 00:00:00 2001
From: Thomas Steen Rasmussen <tykling@bornhack.org>
Date: Thu, 22 Jul 2021 00:07:30 +0200
Subject: [PATCH] calculate profit in the database, skip the margin calculation
 for now

---
 .../templates/ticket_stats_detail.html        | 18 ++++++++------
 src/shop/models.py                            | 24 +++++++------------
 2 files changed, 19 insertions(+), 23 deletions(-)

diff --git a/src/backoffice/templates/ticket_stats_detail.html b/src/backoffice/templates/ticket_stats_detail.html
index 9637a194..7cc54208 100644
--- a/src/backoffice/templates/ticket_stats_detail.html
+++ b/src/backoffice/templates/ticket_stats_detail.html
@@ -14,24 +14,28 @@
     <thead>
     <tr>
       <th>Product</th>
-      <th class="text-center">Orders</th>
-      <th class="text-center">Units Sold</th>
       <th class="text-right">Revenue</th>
       <th class="text-right">Cost</th>
       <th class="text-right">Profit</th>
-      <th class="text-right">Margin</th>
+      <th class="text-center">Orders</th>
+      <th class="text-center">Units Sold</th>
+      <th class="text-right">Total Revenue</th>
+      <th class="text-right">Total Cost</th>
+      <th class="text-right">Total Profit</th>
     </tr>
     </thead>
     <tbody>
     {% for p in product_list %}
     <tr>
       <td>{{ p.name }}</td>
+      <td class="text-right">{{ p.price|floatformat:"2" }}&nbsp;DKK</td>
+      <td class="text-right">{{ p.cost|floatformat:"2" }}&nbsp;DKK</td>
+      <td class="text-right">{{ p.profit|floatformat:"2" }}&nbsp;DKK</td>
       <td class="text-center">{{ p.order_set.count }}</td>
       <td class="text-center">{{ p.total_units_sold }}</td>
-      <td class="text-right">{{ p.price|floatformat:"2" }} DKK</td>
-      <td class="text-right">{{ p.cost|floatformat:"2" }} DKK</td>
-      <td class="text-right">{{ p.profit|floatformat:"2" }} DKK</td>
-      <td class="text-right">{{ p.margin|floatformat:"2" }}%</td>
+      <td class="text-right">{{ p.total_revenue|floatformat:"2" }}&nbsp;DKK</td>
+      <td class="text-right">{{ p.total_cost|floatformat:"2" }}&nbsp;DKK</td>
+      <td class="text-right">{{ p.total_profit|floatformat:"2" }}&nbsp;DKK</td>
     </tr>
     {% endfor %}
     </tbody>
diff --git a/src/shop/models.py b/src/shop/models.py
index efbd3665..bb70cec7 100644
--- a/src/shop/models.py
+++ b/src/shop/models.py
@@ -7,7 +7,7 @@ from django.contrib import messages
 from django.contrib.postgres.fields import DateTimeRangeField
 from django.core.exceptions import ValidationError
 from django.db import models
-from django.db.models.aggregates import Sum
+from django.db.models import F, Sum
 from django.urls import reverse_lazy
 from django.utils import timezone
 from django.utils.dateparse import parse_datetime
@@ -396,7 +396,13 @@ class ProductCategory(CreatedUpdatedModel, UUIDModel):
 
 class ProductStatsManager(models.Manager):
     def with_ticket_stats(self):
-        return self.annotate(total_units_sold=Sum("orderproductrelation__quantity"))
+        return (
+            self.annotate(total_units_sold=Sum("orderproductrelation__quantity"))
+            .annotate(profit=F("price") - F("cost"))
+            .annotate(total_revenue=F("price") * F("total_units_sold"))
+            .annotate(total_cost=F("cost") * F("total_units_sold"))
+            .annotate(total_profit=F("profit") * F("total_units_sold"))
+        )
 
 
 class Product(CreatedUpdatedModel, UUIDModel):
@@ -512,20 +518,6 @@ class Product(CreatedUpdatedModel, UUIDModel):
         # If there is no stock defined the product is generally available.
         return True
 
-    @property
-    def profit(self):
-        try:
-            return self.price - self.cost
-        except ValueError:
-            return 0
-
-    @property
-    def margin(self):
-        try:
-            return (self.profit / self.price) * 100
-        except ValueError:
-            return 0
-
 
 class OrderProductRelation(CreatedUpdatedModel):
     order = models.ForeignKey("shop.Order", on_delete=models.PROTECT)