"""
Test entitlements utilities
"""

from datetime import timedelta

from django.conf import settings
from django.utils.timezone import now
from xmodule.modulestore.tests.django_utils import ModuleStoreTestCase

from course_modes.models import CourseMode
from course_modes.tests.factories import CourseModeFactory
from openedx.core.djangolib.testing.utils import skip_unless_lms
from student.tests.factories import (TEST_PASSWORD, UserFactory, CourseOverviewFactory, CourseEnrollmentFactory)

# Entitlements is not in CMS' INSTALLED_APPS so these imports will error during test collection
if settings.ROOT_URLCONF == 'lms.urls':
    from entitlements.tests.factories import CourseEntitlementFactory
    from entitlements.utils import is_course_run_entitlement_fulfillable


@skip_unless_lms
class TestCourseRunFullfillableForEntitlement(ModuleStoreTestCase):
    """
    Tests for the utility function is_course_run_entitlement_fulfillable
    """

    def setUp(self):
        super(TestCourseRunFullfillableForEntitlement, self).setUp()

        self.user = UserFactory(is_staff=True)
        self.client.login(username=self.user.username, password=TEST_PASSWORD)

    def create_course(
            self,
            start_from_now,
            end_from_now,
            enrollment_start_from_now,
            enrollment_end_from_now,
            upgraded_ended_from_now=1
    ):
        course_overview = CourseOverviewFactory.create(
            start=now() + timedelta(days=start_from_now),
            end=now() + timedelta(days=end_from_now),
            enrollment_start=now() + timedelta(days=enrollment_start_from_now),
            enrollment_end=now() + timedelta(days=enrollment_end_from_now)
        )

        CourseModeFactory(
            course_id=course_overview.id,
            mode_slug=CourseMode.VERIFIED,
            # This must be in the future to ensure it is returned by downstream code.
            expiration_datetime=now() + timedelta(days=upgraded_ended_from_now)
        )
        return course_overview

    def test_course_run_fullfillble(self):
        course_overview = self.create_course(
            start_from_now=-2,
            end_from_now=2,
            enrollment_start_from_now=-1,
            enrollment_end_from_now=1
        )

        entitlement = CourseEntitlementFactory.create(mode=CourseMode.VERIFIED)

        assert is_course_run_entitlement_fulfillable(course_overview.id, entitlement)

    def test_course_run_not_fullfillable_run_ended(self):
        course_overview = self.create_course(
            start_from_now=-3,
            end_from_now=-1,
            enrollment_start_from_now=-3,
            enrollment_end_from_now=-2
        )

        entitlement = CourseEntitlementFactory.create(mode=CourseMode.VERIFIED)

        assert not is_course_run_entitlement_fulfillable(course_overview.id, entitlement)

    def test_course_run_not_fullfillable_enroll_period_ended(self):
        course_overview = self.create_course(
            start_from_now=-3,
            end_from_now=2,
            enrollment_start_from_now=-2,
            enrollment_end_from_now=-1
        )

        entitlement = CourseEntitlementFactory.create(mode=CourseMode.VERIFIED)

        assert not is_course_run_entitlement_fulfillable(course_overview.id, entitlement)

    def test_course_run_fullfillable_user_enrolled(self):
        course_overview = self.create_course(
            start_from_now=-3,
            end_from_now=2,
            enrollment_start_from_now=-2,
            enrollment_end_from_now=1
        )

        entitlement = CourseEntitlementFactory.create(mode=CourseMode.VERIFIED)
        # Enroll User in the Course, but do not update the entitlement
        CourseEnrollmentFactory.create(user=entitlement.user, course_id=course_overview.id)

        assert is_course_run_entitlement_fulfillable(course_overview.id, entitlement)

    def test_course_run_not_fullfillable_upgrade_ended(self):
        course_overview = self.create_course(
            start_from_now=-3,
            end_from_now=2,
            enrollment_start_from_now=-2,
            enrollment_end_from_now=1,
            upgraded_ended_from_now=-1
        )

        entitlement = CourseEntitlementFactory.create(mode=CourseMode.VERIFIED)

        assert not is_course_run_entitlement_fulfillable(course_overview.id, entitlement)