"""
Tests for coursewarehistoryextended
Many aspects of this app are covered by the courseware tests,
but these are specific to the new storage model with multiple
backend tables.
"""


import json
from unittest import skipUnless
from unittest.mock import patch

from django.conf import settings
from django.db import connections
from django.test import TestCase

from lms.djangoapps.courseware.models import BaseStudentModuleHistory, StudentModule, StudentModuleHistory
from lms.djangoapps.courseware.tests.factories import StudentModuleFactory, course_id, location


@skipUnless(settings.FEATURES["ENABLE_CSMH_EXTENDED"], "CSMH Extended needs to be enabled")
class TestStudentModuleHistoryBackends(TestCase):
    """ Tests of data in CSMH and CSMHE """
    # Tell Django to clean out all databases, not just default
    databases = {alias for alias in connections}  # lint-amnesty, pylint: disable=unnecessary-comprehension

    def setUp(self):
        super().setUp()
        for record in (1, 2, 3):
            # This will store into CSMHE via the post_save signal
            csm = StudentModuleFactory.create(module_state_key=location('usage_id'),
                                              course_id=course_id,
                                              state=json.dumps({'type': 'csmhe', 'order': record}))
            # This manually gets us a CSMH record to compare
            csmh = StudentModuleHistory(student_module=csm,
                                        version=None,
                                        created=csm.modified,
                                        state=json.dumps({'type': 'csmh', 'order': record}),
                                        grade=csm.grade,
                                        max_grade=csm.max_grade)
            csmh.save()

    @patch.dict("django.conf.settings.FEATURES", {"ENABLE_CSMH_EXTENDED": True})
    @patch.dict("django.conf.settings.FEATURES", {"ENABLE_READING_FROM_MULTIPLE_HISTORY_TABLES": True})
    def test_get_history_true_true(self):
        student_module = StudentModule.objects.all()
        history = BaseStudentModuleHistory.get_history(student_module)
        assert len(history) == 6
        assert {'type': 'csmhe', 'order': 3} == json.loads(history[0].state)
        assert {'type': 'csmhe', 'order': 2} == json.loads(history[1].state)
        assert {'type': 'csmhe', 'order': 1} == json.loads(history[2].state)
        assert {'type': 'csmh', 'order': 3} == json.loads(history[3].state)
        assert {'type': 'csmh', 'order': 2} == json.loads(history[4].state)
        assert {'type': 'csmh', 'order': 1} == json.loads(history[5].state)

    @patch.dict("django.conf.settings.FEATURES", {"ENABLE_CSMH_EXTENDED": True})
    @patch.dict("django.conf.settings.FEATURES", {"ENABLE_READING_FROM_MULTIPLE_HISTORY_TABLES": False})
    def test_get_history_true_false(self):
        student_module = StudentModule.objects.all()
        history = BaseStudentModuleHistory.get_history(student_module)
        assert len(history) == 3
        assert {'type': 'csmhe', 'order': 3} == json.loads(history[0].state)
        assert {'type': 'csmhe', 'order': 2} == json.loads(history[1].state)
        assert {'type': 'csmhe', 'order': 1} == json.loads(history[2].state)

    @patch.dict("django.conf.settings.FEATURES", {"ENABLE_CSMH_EXTENDED": False})
    @patch.dict("django.conf.settings.FEATURES", {"ENABLE_READING_FROM_MULTIPLE_HISTORY_TABLES": True})
    def test_get_history_false_true(self):
        student_module = StudentModule.objects.all()
        history = BaseStudentModuleHistory.get_history(student_module)
        assert len(history) == 3
        assert {'type': 'csmh', 'order': 3} == json.loads(history[0].state)
        assert {'type': 'csmh', 'order': 2} == json.loads(history[1].state)
        assert {'type': 'csmh', 'order': 1} == json.loads(history[2].state)

    @patch.dict("django.conf.settings.FEATURES", {"ENABLE_CSMH_EXTENDED": False})
    @patch.dict("django.conf.settings.FEATURES", {"ENABLE_READING_FROM_MULTIPLE_HISTORY_TABLES": False})
    def test_get_history_false_false(self):
        student_module = StudentModule.objects.all()
        history = BaseStudentModuleHistory.get_history(student_module)
        assert len(history) == 0