order uchun overdue price qoshildi va pharmacy field orniga factory field qoshildi

core/apps/orders/models/order.py

@@ -1,7 +1,7 @@
 from django.db import models
 
 # shared
-from core.apps.shared.models import BaseModel, Pharmacy
+from core.apps.shared.models import BaseModel, Factory
 # accounts
 from core.apps.accounts.models import User
 
@@ -9,13 +9,17 @@ from core.apps.accounts.models import User
 
 class Order(BaseModel):
     user = models.ForeignKey(User, on_delete=models.CASCADE, related_name='orders')
-    pharmacy = models.ForeignKey(Pharmacy, on_delete=models.CASCADE, related_name='orders')
+    factory = models.ForeignKey(Factory, on_delete=models.CASCADE, related_name='orders', null=True)
 
     total_price = models.DecimalField(decimal_places=2, max_digits=15)
     paid_price = models.DecimalField(decimal_places=2, max_digits=15)
+    overdue_price = models.DecimalField(decimal_places=2, max_digits=15, default=0)
     advance = models.FloatField()
     employee_name = models.CharField(max_length=200)
 
     def __str__(self):
         return f'#{self.id} from {self.user.first_name}, total_price - {self.total_price}, paid - {self.paid_price}'
-    
+    
+    def save(self, *args, **kwargs):
+        self.overdue_price = self.total_price - self.paid_price
+        return super().save(*args, **kwargs)