from datetime import timedelta
from unittest import mock

from django.utils import timezone
from rest_framework.test import APITestCase

from api.models import User
from vehicles.models import Vehicle

STATION = {'station_key': 'test-station'}


class OneWeightTests(APITestCase):
    def setUp(self):
        self.user = User.objects.create_user('op', password='x', can_measure=True)
        self.other = User.objects.create_user('first', password='x')
        self.client.force_authenticate(self.user)
        p = mock.patch('api.views._station_allowed', return_value=True)
        p.start()
        self.addCleanup(p.stop)
        p = mock.patch('api.views.sse_broadcast_update')
        self.sse = p.start()
        self.addCleanup(p.stop)

    def url(self, v):
        return f'/api/vehicles/{v.pk}/one-weight/'

    def make(self, **kw):
        return Vehicle.objects.create(vehicle_number='CB1234', driver_name='D', **kw)

    def test_moves_tare_to_gross_and_finalizes(self):
        when = timezone.now() - timedelta(hours=1)
        v = self.make(tare=1500, tare_date=when, tare_user=self.other, tare_manual=True,
                      tare_manual_user=self.other, tare_manual_date=when, tare_manual_note='n')
        r = self.client.post(self.url(v), STATION, format='json')
        self.assertEqual(r.status_code, 200, r.content)
        v.refresh_from_db()
        self.assertEqual(v.gross, 1500)
        self.assertEqual(v.gross_date, when)
        self.assertEqual(v.gross_user, self.other)
        self.assertTrue(v.gross_manual)
        self.assertEqual(v.gross_manual_user, self.other)
        self.assertEqual(v.gross_manual_date, when)
        self.assertEqual(v.gross_manual_note, 'n')
        for f in ('tare', 'tare_date', 'tare_user', 'tare_manual_user',
                  'tare_manual_date', 'tare_manual_note'):
            self.assertIsNone(getattr(v, f), f)
        self.assertFalse(v.tare_manual)
        self.assertEqual(v.net, 1500)
        self.assertEqual(v.net_user, self.user)
        self.assertIsNotNone(v.net_date)
        self.assertTrue(v.doc_number)
        self.assertEqual(r.data['doc_number'], v.doc_number)
        self.assertEqual(r.data['net'], 1500)
        self.assertIsNone(r.data['tare'])
        self.sse.assert_called_once()
        self.assertEqual(self.sse.call_args.args[:2], ('vehicle', 'updated'))

    def test_gross_already_set(self):
        when = timezone.now()
        v = self.make(gross=9000, gross_date=when, gross_user=self.other)
        r = self.client.post(self.url(v), STATION, format='json')
        self.assertEqual(r.status_code, 200, r.content)
        v.refresh_from_db()
        self.assertEqual((v.gross, v.gross_user, v.gross_date), (9000, self.other, when))
        self.assertIsNone(v.tare)
        self.assertEqual(v.net, 9000)
        self.assertTrue(v.doc_number)

    def _assert_400(self, v):
        r = self.client.post(self.url(v), STATION, format='json')
        self.assertEqual(r.status_code, 400)
        self.assertIn('detail', r.data)
        self.sse.assert_not_called()

    def test_already_finalized(self):
        self._assert_400(self.make(gross=5, net=5, doc_number='2026-1'))

    def test_void(self):
        self._assert_400(self.make(tare=5, is_void=True))

    def test_no_weight(self):
        self._assert_400(self.make())

    def test_both_weights(self):
        self._assert_400(self.make(tare=5, gross=10))

    def test_permission_denied(self):
        v = self.make(tare=5)
        self.client.force_authenticate(self.other)
        r = self.client.post(self.url(v), STATION, format='json')
        self.assertEqual(r.status_code, 403)
        v.refresh_from_db()
        self.assertEqual(v.tare, 5)
        self.assertIsNone(v.doc_number)

    def test_station_not_licensed(self):
        v = self.make(tare=5)
        with mock.patch('api.views._station_allowed', return_value=False):
            r = self.client.post(self.url(v), STATION, format='json')
        self.assertEqual(r.status_code, 403)

    def test_unknown_vehicle_404(self):
        r = self.client.post('/api/vehicles/999999/one-weight/', STATION, format='json')
        self.assertEqual(r.status_code, 404)