wip: adding shopping card functionality

5 files changed, 69 insertions, 7 deletions

diff --git a/pyblackbird_cc/conftest.py b/pyblackbird_cc/conftest.py
index 966a3e5..ef8b62a 100644
--- a/pyblackbird_cc/conftest.py
+++ b/pyblackbird_cc/conftest.py
@@ -1,5 +1,6 @@
 import pytest
 
+from pyblackbird_cc.resources.factories import ResourceModelFactory
 from pyblackbird_cc.users.models import User
 from pyblackbird_cc.users.tests.factories import UserFactory
 
@@ -12,3 +13,8 @@ def _media_storage(settings, tmpdir) -> None:
 @pytest.fixture()
 def user(db) -> User:
     return UserFactory()
+
+
+@pytest.fixture()
+def resource():
+    return ResourceModelFactory()
diff --git a/pyblackbird_cc/payments/migrations/0007_remove_cartitem_quantity_and_more.py b/pyblackbird_cc/payments/migrations/0007_remove_cartitem_quantity_and_more.py
new file mode 100644
index 0000000..e976059
--- /dev/null
+++ b/pyblackbird_cc/payments/migrations/0007_remove_cartitem_quantity_and_more.py
@@ -0,0 +1,23 @@
+# Generated by Django 5.0.4 on 2024-09-14 14:40
+
+from django.conf import settings
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('payments', '0006_subscription_plan'),
+        migrations.swappable_dependency(settings.AUTH_USER_MODEL),
+    ]
+
+    operations = [
+        migrations.RemoveField(
+            model_name='cartitem',
+            name='quantity',
+        ),
+        migrations.AddConstraint(
+            model_name='subscription',
+            constraint=models.UniqueConstraint(fields=('user', 'plan'), name='unique_user_plan'),
+        ),
+    ]
diff --git a/pyblackbird_cc/payments/models.py b/pyblackbird_cc/payments/models.py
index 174e3fe..81bb1c8 100644
--- a/pyblackbird_cc/payments/models.py
+++ b/pyblackbird_cc/payments/models.py
@@ -26,21 +26,25 @@ class ShoppingCart(models.Model):
     def __str__(self):
         return f"Shopping Cart for {self.user.username}"
 
+    def add_resource(self, resource: Resource):
+        item, created = CartItem.objects.get_or_create(
+            cart=self,
+            resource=resource,
+        )
+        if not created:
+            item.save()
+
 
 class CartItem(models.Model):
     cart = models.ForeignKey(ShoppingCart, on_delete=models.CASCADE, related_name="items")
     resource = models.ForeignKey(Resource, on_delete=models.CASCADE)
-    quantity = models.PositiveIntegerField(default=1)
     added_at = models.DateTimeField(auto_now_add=True)
 
     class Meta:
         unique_together = ("cart", "resource")
 
     def __str__(self):
-        return f"{self.quantity} of {self.resource.name} in {self.cart.user.username}'s cart"
-
-    def get_total_price(self):
-        return self.quantity * self.resource.price
+        return f"{self.resource.name} in {self.cart.user.username}'s cart"
 
 
 class SubscriptionPlan(models.Model):
diff --git a/pyblackbird_cc/payments/signals.py b/pyblackbird_cc/payments/signals.py
index e660440..24fc1d8 100644
--- a/pyblackbird_cc/payments/signals.py
+++ b/pyblackbird_cc/payments/signals.py
@@ -5,7 +5,7 @@ from django.db import transaction
 from django.dispatch import receiver
 from django.utils import timezone
 
-from .models import Subscription
+from .models import ShoppingCart, Subscription
 from .models import SubscriptionPlan
 
 
@@ -30,3 +30,10 @@ def assign_default_subscription(sender, request, user, **kwargs):
             start_date=timezone.now(),
             end_date=timezone.now() + timedelta(days=365),  # Example: 30 days
         )
+
+
+@receiver(user_signed_up)
+def assign_user_a_shopping_cart(sender, request, user, **kwargs):
+    with transaction.atomic():
+        # Create a ShoppingCart for the new user
+        ShoppingCart.objects.create(user=user)
diff --git a/pyblackbird_cc/payments/tests/test_models.py b/pyblackbird_cc/payments/tests/test_models.py
index 65e7484..fd26fea 100644
--- a/pyblackbird_cc/payments/tests/test_models.py
+++ b/pyblackbird_cc/payments/tests/test_models.py
@@ -4,7 +4,7 @@ from django.contrib.auth import get_user_model
 from django.db import IntegrityError
 from django.test import RequestFactory
 
-from pyblackbird_cc.payments.models import Subscription
+from pyblackbird_cc.payments.models import ShoppingCart, Subscription
 from pyblackbird_cc.payments.models import SubscriptionPlan
 
 User = get_user_model()
@@ -64,3 +64,25 @@ def test_user_signup_assigns_free_subscription(user_data):
 
     # Additional assertions can be added here to check other properties
     # of the SubscriptionPlan or Subscription as needed
+
+
+@pytest.mark.django_db
+def test_shopping_cart_is_created_when_user_is_created(user_data):
+    user = User.objects.create_user(**user_data)  # type: ignore
+    request = RequestFactory().get("/")
+    user_signed_up.send(sender=user.__class__, request=request, user=user)
+    shopping_cart = ShoppingCart.objects.get(user=user)
+    assert shopping_cart is not None
+
+
+# When the user adds a `Resource` to their cart, create a new `CartItem` instance and associate it with the user's `ShoppingCart` and the selected `Resource`.
+
+
+@pytest.mark.django_db
+def test_cart_item_is_created_when_resource_is_added_to_cart(user_data, resource):
+    user = User.objects.create_user(**user_data)  # type: ignore
+    request = RequestFactory().get("/")
+    user_signed_up.send(sender=user.__class__, request=request, user=user)
+    users_cart = ShoppingCart.objects.get(user=user)
+    users_cart.add_resource(resource)
+    assert users_cart.items.count() == 1  # type: ignore