from decimal import Decimal

from django.contrib.auth import get_user_model
from django.test import Client, TestCase
from django.urls import reverse

from contacts.models import Contact
from payments.models import Invoice
from payments.services import next_invoice_number


class PaymentsPortalTests(TestCase):
    def setUp(self):
        User = get_user_model()
        self.user = User.objects.create_user("biller", password="test-pass-123")
        self.client = Client()
        self.client.login(username="biller", password="test-pass-123")
        self.contact = Contact.objects.create(
            email="pay@example.com", first_name="Pat", last_name="Lee"
        )

    def test_list_requires_login(self):
        anon = Client()
        self.assertEqual(anon.get(reverse("payments:invoice_list")).status_code, 302)

    def test_create_draft_invoice(self):
        response = self.client.post(
            reverse("payments:invoice_create"),
            {
                "contact": str(self.contact.pk),
                "description": "Website package",
                "amount": "150.00",
            },
        )
        self.assertEqual(response.status_code, 302)
        inv = Invoice.objects.get()
        self.assertEqual(inv.amount, Decimal("150.00"))
        self.assertEqual(inv.status, Invoice.Status.DRAFT)
        self.assertTrue(inv.number.startswith("INV-"))

    def test_next_number_increments(self):
        n1 = next_invoice_number()
        Invoice.objects.create(
            number=n1,
            contact=self.contact,
            description="a",
            amount=Decimal("1.00"),
        )
        n2 = next_invoice_number()
        self.assertNotEqual(n1, n2)