Add more stats

* Finished (count)
* Unfinished (count)
* Refunded (count)

games/models.py

@@ -33,6 +33,17 @@ class Edition(models.Model):
         return self.name
 
 
+class PurchaseQueryset(models.QuerySet):
+    def refunded(self):
+        return self.filter(date_refunded__isnull=False)
+
+    def not_refunded(self):
+        return self.filter(date_refunded__isnull=True)
+
+    def finished(self):
+        return self.filter(date_finished__isnull=False)
+
+
 class Purchase(models.Model):
     PHYSICAL = "ph"
     DIGITAL = "di"
@@ -53,6 +64,8 @@ class Purchase(models.Model):
         (PIRATED, "Pirated"),
     ]
 
+    objects = PurchaseQueryset().as_manager()
+
     edition = models.ForeignKey("Edition", on_delete=models.CASCADE)
     platform = models.ForeignKey(
         "Platform", on_delete=models.CASCADE, default=None, null=True, blank=True