project initialization

backend/tests/contract/test_retail_sales_post.py

@@ -0,0 +1,388 @@
+"""
+Contract test for POST /retail/sales endpoint.
+This test MUST fail before implementation.
+"""
+
+import pytest
+from django.test import TestCase
+from django.urls import reverse
+from rest_framework.test import APIClient
+from rest_framework import status
+import json
+
+
+class RetailSalesPostContractTest(TestCase):
+    def setUp(self):
+        self.client = APIClient()
+        self.sales_url = '/api/v1/retail/sales/'
+
+        # Tenant authentication header
+        self.tenant_auth = {'HTTP_AUTHORIZATION': 'Bearer tenant_token'}
+
+        # Valid sale data
+        self.sale_data = {
+            'customer': {
+                'name': 'John Doe',
+                'email': 'john.doe@example.com',
+                'phone': '+60123456789',
+                'address': {
+                    'street': '123 Customer Street',
+                    'city': 'Kuala Lumpur',
+                    'state': 'Wilayah Persekutuan',
+                    'postal_code': '50000',
+                    'country': 'Malaysia'
+                }
+            },
+            'items': [
+                {
+                    'product_id': 'product-001',
+                    'sku': 'LPT-001',
+                    'quantity': 2,
+                    'unit_price': 2499.99,
+                    'discount_percentage': 5.0,
+                    'tax_rate': 6.0
+                },
+                {
+                    'product_id': 'product-002',
+                    'sku': 'MOU-001',
+                    'quantity': 1,
+                    'unit_price': 99.99,
+                    'discount_percentage': 0.0,
+                    'tax_rate': 6.0
+                }
+            ],
+            'payment': {
+                'method': 'CASH',
+                'amount_paid': 5300.00,
+                'reference_number': 'CASH-001'
+            },
+            'discount': {
+                'type': 'percentage',
+                'value': 2.0,
+                'reason': 'Loyalty discount'
+            },
+            'notes': 'Customer requested expedited delivery',
+            'sales_channel': 'IN_STORE',
+            'staff_id': 'staff-001'
+        }
+
+    def test_create_sale_success(self):
+        """Test successful sale creation."""
+        response = self.client.post(
+            self.sales_url,
+            data=json.dumps(self.sale_data),
+            content_type='application/json',
+            **self.tenant_auth
+        )
+
+        # This should fail before implementation
+        assert response.status_code == status.HTTP_201_CREATED
+
+        data = response.json()
+        assert 'id' in data
+        assert data['status'] == 'COMPLETED'
+        assert 'customer' in data
+        assert 'items' in data
+        assert 'payment' in data
+        assert 'totals' in data
+
+        # Check customer information
+        customer = data['customer']
+        assert customer['name'] == self.sale_data['customer']['name']
+        assert customer['email'] == self.sale_data['customer']['email']
+
+        # Check items
+        items = data['items']
+        assert len(items) == 2
+        assert items[0]['product_id'] == self.sale_data['items'][0]['product_id']
+        assert items[0]['quantity'] == self.sale_data['items'][0]['quantity']
+
+        # Check payment
+        payment = data['payment']
+        assert payment['method'] == self.sale_data['payment']['method']
+        assert payment['amount_paid'] == self.sale_data['payment']['amount_paid']
+
+        # Check totals
+        totals = data['totals']
+        assert 'subtotal' in totals
+        assert 'discount_amount' in totals
+        assert 'tax_amount' in totals
+        assert 'total_amount' in totals
+
+        # Should have timestamps
+        assert 'created_at' in data
+        assert 'updated_at' in data
+
+        # Should have tenant_id from context
+        assert 'tenant_id' in data
+
+    def test_create_sale_unauthorized(self):
+        """Test sale creation without authentication."""
+        response = self.client.post(
+            self.sales_url,
+            data=json.dumps(self.sale_data),
+            content_type='application/json'
+        )
+
+        assert response.status_code == status.HTTP_401_UNAUTHORIZED
+
+    def test_create_sale_missing_required_fields(self):
+        """Test sale creation with missing required fields."""
+        incomplete_data = self.sale_data.copy()
+        del incomplete_data['customer']
+
+        response = self.client.post(
+            self.sales_url,
+            data=json.dumps(incomplete_data),
+            content_type='application/json',
+            **self.tenant_auth
+        )
+
+        assert response.status_code == status.HTTP_400_BAD_REQUEST
+
+        data = response.json()
+        assert 'customer' in data.get('errors', {})
+
+    def test_create_sale_empty_items(self):
+        """Test sale creation with empty items list."""
+        invalid_data = self.sale_data.copy()
+        invalid_data['items'] = []
+
+        response = self.client.post(
+            self.sales_url,
+            data=json.dumps(invalid_data),
+            content_type='application/json',
+            **self.tenant_auth
+        )
+
+        assert response.status_code == status.HTTP_400_BAD_REQUEST
+
+    def test_create_sale_invalid_payment_method(self):
+        """Test sale creation with invalid payment method."""
+        invalid_data = self.sale_data.copy()
+        invalid_data['payment']['method'] = 'INVALID_METHOD'
+
+        response = self.client.post(
+            self.sales_url,
+            data=json.dumps(invalid_data),
+            content_type='application/json',
+            **self.tenant_auth
+        )
+
+        assert response.status_code == status.HTTP_400_BAD_REQUEST
+
+    def test_create_sale_insufficient_payment(self):
+        """Test sale creation with insufficient payment amount."""
+        invalid_data = self.sale_data.copy()
+        invalid_data['payment']['amount_paid'] = 100.00  # Much less than total
+
+        response = self.client.post(
+            self.sales_url,
+            data=json.dumps(invalid_data),
+            content_type='application/json',
+            **self.tenant_auth
+        )
+
+        assert response.status_code == status.HTTP_400_BAD_REQUEST
+
+    def test_create_sale_negative_quantity(self):
+        """Test sale creation with negative quantity."""
+        invalid_data = self.sale_data.copy()
+        invalid_data['items'][0]['quantity'] = -1
+
+        response = self.client.post(
+            self.sales_url,
+            data=json.dumps(invalid_data),
+            content_type='application/json',
+            **self.tenant_auth
+        )
+
+        assert response.status_code == status.HTTP_400_BAD_REQUEST
+
+    def test_create_sale_invalid_discount_percentage(self):
+        """Test sale creation with invalid discount percentage."""
+        invalid_data = self.sale_data.copy()
+        invalid_data['items'][0]['discount_percentage'] = 150.0  # Over 100%
+
+        response = self.client.post(
+            self.sales_url,
+            data=json.dumps(invalid_data),
+            content_type='application/json',
+            **self.tenant_auth
+        )
+
+        assert response.status_code == status.HTTP_400_BAD_REQUEST
+
+    def test_create_sale_with_installment(self):
+        """Test sale creation with installment payment."""
+        installment_data = self.sale_data.copy()
+        installment_data['payment']['method'] = 'INSTALLMENT'
+        installment_data['payment']['installment_plan'] = {
+            'down_payment': 1000.00,
+            'number_of_installments': 12,
+            'installment_amount': 358.33,
+            'first_installment_date': '2024-02-01'
+        }
+
+        response = self.client.post(
+            self.sales_url,
+            data=json.dumps(installment_data),
+            content_type='application/json',
+            **self.tenant_auth
+        )
+
+        if response.status_code == status.HTTP_201_CREATED:
+            data = response.json()
+            assert data['status'] == 'COMPLETED'
+            assert 'installment_plan' in data['payment']
+
+    def test_create_sale_with_multiple_payments(self):
+        """Test sale creation with multiple payment methods."""
+        multi_payment_data = self.sale_data.copy()
+        multi_payment_data['payment'] = [
+            {
+                'method': 'CASH',
+                'amount_paid': 2000.00,
+                'reference_number': 'CASH-001'
+            },
+            {
+                'method': 'CARD',
+                'amount_paid': 3300.00,
+                'reference_number': 'CARD-001',
+                'card_last4': '4242'
+            }
+        ]
+
+        response = self.client.post(
+            self.sales_url,
+            data=json.dumps(multi_payment_data),
+            content_type='application/json',
+            **self.tenant_auth
+        )
+
+        if response.status_code == status.HTTP_201_CREATED:
+            data = response.json()
+            assert len(data['payment']) == 2
+            assert data['payment'][0]['method'] == 'CASH'
+
+    def test_create_sale_with_loyalty_points(self):
+        """Test sale creation with loyalty points redemption."""
+        loyalty_data = self.sale_data.copy()
+        loyalty_data['loyalty'] = {
+            'points_used': 1000,
+            'points_value': 100.00,
+            'customer_id': 'customer-001'
+        }
+
+        response = self.client.post(
+            self.sales_url,
+            data=json.dumps(loyalty_data),
+            content_type='application/json',
+            **self.tenant_auth
+        )
+
+        if response.status_code == status.HTTP_201_CREATED:
+            data = response.json()
+            assert 'loyalty' in data
+            assert data['loyalty']['points_used'] == 1000
+
+    def test_create_sale_with_delivery_info(self):
+        """Test sale creation with delivery information."""
+        delivery_data = self.sale_data.copy()
+        delivery_data['delivery'] = {
+            'method': 'DELIVERY',
+            'address': self.sale_data['customer']['address'],
+            'scheduled_date': '2024-01-20',
+            'delivery_fee': 50.00,
+            'notes': 'Leave at front door'
+        }
+
+        response = self.client.post(
+            self.sales_url,
+            data=json.dumps(delivery_data),
+            content_type='application/json',
+            **self.tenant_auth
+        )
+
+        if response.status_code == status.HTTP_201_CREATED:
+            data = response.json()
+            assert 'delivery' in data
+            assert data['delivery']['method'] == 'DELIVERY'
+
+    def test_create_sale_with_exchange_items(self):
+        """Test sale creation with item exchange."""
+        exchange_data = self.sale_data.copy()
+        exchange_data['exchange'] = {
+            'items': [
+                {
+                    'product_id': 'old-product-001',
+                    'sku': 'OLD-001',
+                    'condition': 'GOOD',
+                    'exchange_value': 500.00
+                }
+            ],
+            'total_exchange_value': 500.00
+        }
+
+        response = self.client.post(
+            self.sales_url,
+            data=json.dumps(exchange_data),
+            content_type='application/json',
+            **self.tenant_auth
+        )
+
+        if response.status_code == status.HTTP_201_CREATED:
+            data = response.json()
+            assert 'exchange' in data
+            assert len(data['exchange']['items']) == 1
+
+    def test_create_sale_tax_calculation(self):
+        """Test that tax calculation is correct."""
+        response = self.client.post(
+            self.sales_url,
+            data=json.dumps(self.sale_data),
+            content_type='application/json',
+            **self.tenant_auth
+        )
+
+        if response.status_code == status.HTTP_201_CREATED:
+            data = response.json()
+            totals = data['totals']
+
+            # Verify tax calculation (6% GST on subtotal after discounts)
+            # This will be validated once implementation exists
+            assert 'tax_amount' in totals
+            assert totals['tax_amount'] >= 0
+
+    def test_create_sale_tenant_isolation(self):
+        """Test that sale creation respects tenant isolation."""
+        response = self.client.post(
+            self.sales_url,
+            data=json.dumps(self.sale_data),
+            content_type='application/json',
+            **self.tenant_auth
+        )
+
+        if response.status_code == status.HTTP_201_CREATED:
+            data = response.json()
+            # Sale should be created in the authenticated tenant's context
+            assert 'tenant_id' in data
+            # This will be validated once implementation exists
+
+    def test_create_sale_inventory_validation(self):
+        """Test that sale creation validates inventory availability."""
+        response = self.client.post(
+            self.sales_url,
+            data=json.dumps(self.sale_data),
+            content_type='application/json',
+            **self.tenant_auth
+        )
+
+        # This test will ensure that the system checks if sufficient stock is available
+        # The test should pass if implementation exists and validates inventory
+        if response.status_code == status.HTTP_201_CREATED:
+            # Success means inventory was available
+            pass
+        elif response.status_code == status.HTTP_400_BAD_REQUEST:
+            # This could also be valid if inventory validation fails
+            pass