import datetime
from unittest.mock import patch
from django.test import TestCase
from django.contrib.auth import get_user_model
from modules.task_management.tasks import notify_upcoming_tasks
from modules.task_management.models import Task
from modules.fleet.models import Vehicle, WorkOrder


class NotifyUpcomingTasksTests(TestCase):
    def setUp(self):
        User = get_user_model()
        self.user = User.objects.create_user(
            username="serviser-notif",
            email="serviser@example.test",
            password="pass",
        )
        self.vehicle = Vehicle.objects.create(
            registration_number="ZG-NOTIF-01",
            asset_type='crane',
        )

    @patch('modules.fleet.services.NotificationService.create_notification')
    def test_notifies_for_task_scheduled_tomorrow(self, mock_notify):
        tomorrow = datetime.date.today() + datetime.timedelta(days=1)
        Task.objects.create(
            title="Sutrašnji zadatak",
            assigned_to=self.user,
            vehicle=self.vehicle,
            status='aktivan',
            scheduled_date=tomorrow,
        )
        result = notify_upcoming_tasks()
        self.assertEqual(result['notified'], 1)
        mock_notify.assert_called_once()
        call_kwargs = mock_notify.call_args.kwargs
        self.assertEqual(call_kwargs['recipient'], self.user)
        self.assertIn('Sutrašnji zadatak', call_kwargs['title'])
        self.assertEqual(call_kwargs['level'], 'info')
        self.assertTrue(call_kwargs.get('send_email'))

    @patch('modules.fleet.services.NotificationService.create_notification')
    def test_notifies_multiple_upcoming_tasks(self, mock_notify):
        tomorrow = datetime.date.today() + datetime.timedelta(days=1)
        Task.objects.create(title="Task A", assigned_to=self.user, vehicle=self.vehicle,
                            status='aktivan', scheduled_date=tomorrow)
        Task.objects.create(title="Task B", assigned_to=self.user, vehicle=self.vehicle,
                            status='servis', scheduled_date=tomorrow)
        result = notify_upcoming_tasks()
        self.assertEqual(result['notified'], 2)
        self.assertEqual(mock_notify.call_count, 2)

    @patch('modules.fleet.services.NotificationService.create_notification')
    def test_skips_task_without_scheduled_date(self, mock_notify):
        Task.objects.create(
            title="Bez datuma", assigned_to=self.user, vehicle=self.vehicle,
            status='aktivan', scheduled_date=None,
        )
        result = notify_upcoming_tasks()
        self.assertEqual(result['notified'], 0)
        mock_notify.assert_not_called()

    @patch('modules.fleet.services.NotificationService.create_notification')
    def test_skips_task_scheduled_today(self, mock_notify):
        today = datetime.date.today()
        Task.objects.create(
            title="Danas", assigned_to=self.user, vehicle=self.vehicle,
            status='aktivan', scheduled_date=today,
        )
        result = notify_upcoming_tasks()
        self.assertEqual(result['notified'], 0)
        mock_notify.assert_not_called()

    @patch('modules.fleet.services.NotificationService.create_notification')
    def test_skips_task_scheduled_in_past(self, mock_notify):
        yesterday = datetime.date.today() - datetime.timedelta(days=1)
        Task.objects.create(
            title="Jučer", assigned_to=self.user, vehicle=self.vehicle,
            status='aktivan', scheduled_date=yesterday,
        )
        result = notify_upcoming_tasks()
        self.assertEqual(result['notified'], 0)
        mock_notify.assert_not_called()

    @patch('modules.fleet.services.NotificationService.create_notification')
    def test_skips_finished_task(self, mock_notify):
        tomorrow = datetime.date.today() + datetime.timedelta(days=1)
        vehicle2 = Vehicle.objects.create(registration_number="ZG-NOTIF-02", asset_type='crane')
        work_order = WorkOrder.objects.create(
            vehicle=vehicle2, creator=self.user, purpose='defektaza',
            status='closed', start_mileage=100, end_mileage=200,
        )
        Task.objects.create(
            title="Završeni", assigned_to=self.user, vehicle=vehicle2,
            status='zavrsen', scheduled_date=tomorrow, work_order=work_order,
        )
        result = notify_upcoming_tasks()
        self.assertEqual(result['notified'], 0)
        mock_notify.assert_not_called()

    @patch('modules.fleet.services.NotificationService.create_notification')
    def test_skips_cancelled_task(self, mock_notify):
        tomorrow = datetime.date.today() + datetime.timedelta(days=1)
        vehicle3 = Vehicle.objects.create(registration_number="ZG-NOTIF-03", asset_type='crane')
        work_order = WorkOrder.objects.create(
            vehicle=vehicle3, creator=self.user, purpose='kontrola',
            status='closed', start_mileage=50, end_mileage=100,
        )
        Task.objects.create(
            title="Otkazani", assigned_to=self.user, vehicle=vehicle3,
            status='neaktivan', scheduled_date=tomorrow, work_order=work_order,
        )
        result = notify_upcoming_tasks()
        self.assertEqual(result['notified'], 0)
        mock_notify.assert_not_called()

    @patch('modules.fleet.services.NotificationService.create_notification')
    def test_skips_task_without_assigned_user(self, mock_notify):
        tomorrow = datetime.date.today() + datetime.timedelta(days=1)
        Task.objects.create(
            title="Bez servisera", assigned_to=None, vehicle=self.vehicle,
            status='aktivan', scheduled_date=tomorrow,
        )
        result = notify_upcoming_tasks()
        self.assertEqual(result['notified'], 0)
        mock_notify.assert_not_called()

    @patch('modules.fleet.services.NotificationService.create_notification')
    def test_result_includes_date_string(self, mock_notify):
        result = notify_upcoming_tasks()
        tomorrow = datetime.date.today() + datetime.timedelta(days=1)
        self.assertEqual(result['date'], tomorrow.isoformat())
        self.assertEqual(result['notified'], 0)