Models updated based on Adwaith's feedback

invoice/models.py

@@ -8,7 +8,7 @@ class Invoice(models.Model):
     raised_date = models.DateField()
     due_date = models.DateField()
     paid_date = models.DateField(null=True, blank=True)
-    is_archived = models.BooleanField()
+    is_archived = models.BooleanField(default=False)
 
     def __str__(self):
         return self.invoice_id
@@ -18,7 +18,11 @@ class Item(models.Model):
     name = models.TextField(blank=False, null=False)
     amount = models.DecimalField()
     quantity = models.IntegerField()
-    invoice = models.OneToOneField(Invoice, on_delete=models.CASCADE)
+    invoice = models.ForeignKey(Invoice, on_delete=models.CASCADE)
+
+    @property
+    def item_total(self):
+        return self.amount * self.quantity
 
     def __str__(self):
         return self.name

project/models.py

@@ -6,7 +6,7 @@ class Project(models.Model):
     name = models.CharField(max_length=30)
     project_image = models.ImageField(upload_to='project_images', null=True, blank=True)
     client = models.ForeignKey(Client, on_delete=models.CASCADE)
-    total_cost = models.DecimalField()
+    total_compensation = models.DecimalField()
     start_date = models.DateField()
     end_date = models.DateField()