# -*- coding: utf-8 -*-

import copy
import mock
from mock import patch
import shutil
import lxml.html
from lxml import etree
import ddt

from datetime import timedelta
from fs.osfs import OSFS
from json import loads
from path import path
from textwrap import dedent
from uuid import uuid4
from functools import wraps
from unittest import SkipTest

from django.conf import settings
from django.contrib.auth.models import User
from django.test import TestCase
from django.test.utils import override_settings

from openedx.core.lib.tempdir import mkdtemp_clean
from contentstore.tests.utils import parse_json, AjaxEnabledTestClient, CourseTestCase
from contentstore.views.component import ADVANCED_COMPONENT_TYPES

from edxval.api import create_video, get_videos_for_course

from xmodule.contentstore.django import contentstore
from xmodule.contentstore.utils import restore_asset_from_trashcan, empty_asset_trashcan
from xmodule.exceptions import InvalidVersionError
from xmodule.modulestore import ModuleStoreEnum
from xmodule.modulestore.exceptions import ItemNotFoundError
from xmodule.modulestore.inheritance import own_metadata
from opaque_keys.edx.keys import UsageKey, CourseKey
from opaque_keys.edx.locations import AssetLocation, CourseLocator
from xmodule.modulestore.tests.factories import CourseFactory, ItemFactory, check_mongo_calls
from xmodule.modulestore.xml_exporter import export_course_to_xml
from xmodule.modulestore.xml_importer import import_course_from_xml, perform_xlint

from xmodule.capa_module import CapaDescriptor
from xmodule.course_module import CourseDescriptor, Textbook
from xmodule.seq_module import SequenceDescriptor

from contentstore.utils import delete_course_and_groups, reverse_url, reverse_course_url
from django_comment_common.utils import are_permissions_roles_seeded

from student import auth
from student.models import CourseEnrollment
from student.roles import CourseCreatorRole, CourseInstructorRole
from opaque_keys import InvalidKeyError
from contentstore.tests.utils import get_url
from course_action_state.models import CourseRerunState, CourseRerunUIStateManager

from course_action_state.managers import CourseActionStateItemNotFoundError
from xmodule.contentstore.content import StaticContent
from xmodule.modulestore.django import modulestore


TEST_DATA_CONTENTSTORE = copy.deepcopy(settings.CONTENTSTORE)
TEST_DATA_CONTENTSTORE['DOC_STORE_CONFIG']['db'] = 'test_xcontent_%s' % uuid4().hex

TEST_DATA_DIR = settings.COMMON_TEST_DATA_ROOT


def requires_pillow_jpeg(func):
    """
    A decorator to indicate that the function requires JPEG support for Pillow,
    otherwise it cannot be run
    """
    @wraps(func)
    def decorated_func(*args, **kwargs):
        """
        Execute the function if we have JPEG support in Pillow.
        """
        try:
            from PIL import Image
        except ImportError:
            raise SkipTest("Pillow is not installed (or not found)")
        if not getattr(Image.core, "jpeg_decoder", False):
            raise SkipTest("Pillow cannot open JPEG files")
        return func(*args, **kwargs)
    return decorated_func


@override_settings(CONTENTSTORE=TEST_DATA_CONTENTSTORE)
class ContentStoreTestCase(CourseTestCase):
    """
    Base class for Content Store Test Cases
    """


class ImportRequiredTestCases(ContentStoreTestCase):
    """
    Tests which legitimately need to import a course
    """
    def test_no_static_link_rewrites_on_import(self):
        course_items = import_course_from_xml(
            self.store, self.user.id, TEST_DATA_DIR, ['toy'], create_if_not_present=True
        )
        course = course_items[0]

        handouts_usage_key = course.id.make_usage_key('course_info', 'handouts')
        handouts = self.store.get_item(handouts_usage_key)
        self.assertIn('/static/', handouts.data)

        handouts_usage_key = course.id.make_usage_key('html', 'toyhtml')
        handouts = self.store.get_item(handouts_usage_key)
        self.assertIn('/static/', handouts.data)

    def test_xlint_fails(self):
        err_cnt = perform_xlint(TEST_DATA_DIR, ['toy'])
        self.assertGreater(err_cnt, 0)

    def test_about_overrides(self):
        '''
        This test case verifies that a course can use specialized override for about data,
        e.g. /about/Fall_2012/effort.html
        while there is a base definition in /about/effort.html
        '''
        course_items = import_course_from_xml(
            self.store, self.user.id, TEST_DATA_DIR, ['toy'], create_if_not_present=True
        )
        course_key = course_items[0].id
        effort = self.store.get_item(course_key.make_usage_key('about', 'effort'))
        self.assertEqual(effort.data, '6 hours')

        # this one should be in a non-override folder
        effort = self.store.get_item(course_key.make_usage_key('about', 'end_date'))
        self.assertEqual(effort.data, 'TBD')

    @requires_pillow_jpeg
    def test_asset_import(self):
        '''
        This test validates that an image asset is imported and a thumbnail was generated for a .gif
        '''
        content_store = contentstore()

        import_course_from_xml(
            self.store, self.user.id, TEST_DATA_DIR, ['toy'], static_content_store=content_store, verbose=True,
            create_if_not_present=True
        )

        course = self.store.get_course(self.store.make_course_key('edX', 'toy', '2012_Fall'))

        self.assertIsNotNone(course)

        # make sure we have some assets in our contentstore
        all_assets, __ = content_store.get_all_content_for_course(course.id)
        self.assertGreater(len(all_assets), 0)

        # make sure we have some thumbnails in our contentstore
        all_thumbnails = content_store.get_all_content_thumbnails_for_course(course.id)
        self.assertGreater(len(all_thumbnails), 0)

        location = AssetLocation.from_deprecated_string('/c4x/edX/toy/asset/just_a_test.jpg')
        content = content_store.find(location)
        self.assertIsNotNone(content)

        self.assertIsNotNone(content.thumbnail_location)
        thumbnail = content_store.find(content.thumbnail_location)
        self.assertIsNotNone(thumbnail)

    def test_course_info_updates_import_export(self):
        """
        Test that course info updates are imported and exported with all content fields ('data', 'items')
        """
        content_store = contentstore()
        data_dir = TEST_DATA_DIR
        courses = import_course_from_xml(
            self.store, self.user.id, data_dir, ['course_info_updates'],
            static_content_store=content_store, verbose=True, create_if_not_present=True
        )

        course = courses[0]
        self.assertIsNotNone(course)

        course_updates = self.store.get_item(course.id.make_usage_key('course_info', 'updates'))
        self.assertIsNotNone(course_updates)

        # check that course which is imported has files 'updates.html' and 'updates.items.json'
        filesystem = OSFS(data_dir + '/course_info_updates/info')
        self.assertTrue(filesystem.exists('updates.html'))
        self.assertTrue(filesystem.exists('updates.items.json'))

        # verify that course info update module has same data content as in data file from which it is imported
        # check 'data' field content
        with filesystem.open('updates.html', 'r') as course_policy:
            on_disk = course_policy.read()
            self.assertEqual(course_updates.data, on_disk)

        # check 'items' field content
        with filesystem.open('updates.items.json', 'r') as course_policy:
            on_disk = loads(course_policy.read())
            self.assertEqual(course_updates.items, on_disk)

        # now export the course to a tempdir and test that it contains files 'updates.html' and 'updates.items.json'
        # with same content as in course 'info' directory
        root_dir = path(mkdtemp_clean())
        print 'Exporting to tempdir = {0}'.format(root_dir)
        export_course_to_xml(self.store, content_store, course.id, root_dir, 'test_export')

        # check that exported course has files 'updates.html' and 'updates.items.json'
        filesystem = OSFS(root_dir / 'test_export/info')
        self.assertTrue(filesystem.exists('updates.html'))
        self.assertTrue(filesystem.exists('updates.items.json'))

        # verify that exported course has same data content as in course_info_update module
        with filesystem.open('updates.html', 'r') as grading_policy:
            on_disk = grading_policy.read()
            self.assertEqual(on_disk, course_updates.data)

        with filesystem.open('updates.items.json', 'r') as grading_policy:
            on_disk = loads(grading_policy.read())
            self.assertEqual(on_disk, course_updates.items)

    def test_rewrite_nonportable_links_on_import(self):
        content_store = contentstore()

        import_course_from_xml(
            self.store, self.user.id, TEST_DATA_DIR, ['toy'],
            static_content_store=content_store, create_if_not_present=True
        )

        # first check a static asset link
        course_key = self.store.make_course_key('edX', 'toy', 'run')
        html_module_location = course_key.make_usage_key('html', 'nonportable')
        html_module = self.store.get_item(html_module_location)
        self.assertIn('/static/foo.jpg', html_module.data)

        # then check a intra courseware link
        html_module_location = course_key.make_usage_key('html', 'nonportable_link')
        html_module = self.store.get_item(html_module_location)
        self.assertIn('/jump_to_id/nonportable_link', html_module.data)

    def verify_content_existence(self, store, root_dir, course_id, dirname, category_name, filename_suffix=''):
        filesystem = OSFS(root_dir / 'test_export')
        self.assertTrue(filesystem.exists(dirname))

        items = store.get_items(course_id, qualifiers={'category': category_name})

        for item in items:
            filesystem = OSFS(root_dir / ('test_export/' + dirname))
            self.assertTrue(filesystem.exists(item.location.name + filename_suffix))

    @mock.patch('xmodule.course_module.requests.get')
    def test_export_course_roundtrip(self, mock_get):
        mock_get.return_value.text = dedent("""
            <?xml version="1.0"?><table_of_contents>
            <entry page="5" page_label="ii" name="Table of Contents"/>
            </table_of_contents>
        """).strip()

        content_store = contentstore()
        course_id = self.import_and_populate_course()

        root_dir = path(mkdtemp_clean())
        print 'Exporting to tempdir = {0}'.format(root_dir)

        # export out to a tempdir
        export_course_to_xml(self.store, content_store, course_id, root_dir, 'test_export')

        # check for static tabs
        self.verify_content_existence(self.store, root_dir, course_id, 'tabs', 'static_tab', '.html')

        # check for about content
        self.verify_content_existence(self.store, root_dir, course_id, 'about', 'about', '.html')

        # assert that there is an html and video directory in drafts:
        draft_dir = OSFS(root_dir / 'test_export/drafts')
        self.assertTrue(draft_dir.exists('html'))
        self.assertTrue(draft_dir.exists('video'))
        # and assert that they contain the created modules
        self.assertIn(self.DRAFT_HTML + ".xml", draft_dir.listdir('html'))
        self.assertIn(self.DRAFT_VIDEO + ".xml", draft_dir.listdir('video'))
        # and assert the child of the orphaned draft wasn't exported
        self.assertNotIn(self.ORPHAN_DRAFT_HTML + ".xml", draft_dir.listdir('html'))

        # check for grading_policy.json
        filesystem = OSFS(root_dir / 'test_export/policies/2012_Fall')
        self.assertTrue(filesystem.exists('grading_policy.json'))

        course = self.store.get_course(course_id)
        # compare what's on disk compared to what we have in our course
        with filesystem.open('grading_policy.json', 'r') as grading_policy:
            on_disk = loads(grading_policy.read())
            self.assertEqual(on_disk, course.grading_policy)

        # check for policy.json
        self.assertTrue(filesystem.exists('policy.json'))

        # compare what's on disk to what we have in the course module
        with filesystem.open('policy.json', 'r') as course_policy:
            on_disk = loads(course_policy.read())
            self.assertIn('course/2012_Fall', on_disk)
            self.assertEqual(on_disk['course/2012_Fall'], own_metadata(course))

        # remove old course
        self.store.delete_course(course_id, self.user.id)

        # reimport over old course
        self.check_import(root_dir, content_store, course_id)

        # import to different course id
        new_course_id = self.store.make_course_key('anotherX', 'anotherToy', 'Someday')
        self.check_import(root_dir, content_store, new_course_id)
        self.assertCoursesEqual(course_id, new_course_id)

        shutil.rmtree(root_dir)

    def check_import(self, root_dir, content_store, course_id):
        """Imports the course in root_dir into the given course_id and verifies its content"""
        # reimport
        import_course_from_xml(
            self.store,
            self.user.id,
            root_dir,
            ['test_export'],
            static_content_store=content_store,
            target_id=course_id,
        )

        # verify content of the course
        self.check_populated_course(course_id)

        # verify additional export attributes
        def verify_export_attrs_removed(attributes):
            """Verifies all temporary attributes added during export are removed"""
            self.assertNotIn('index_in_children_list', attributes)
            self.assertNotIn('parent_sequential_url', attributes)
            self.assertNotIn('parent_url', attributes)

        vertical = self.store.get_item(course_id.make_usage_key('vertical', self.TEST_VERTICAL))
        verify_export_attrs_removed(vertical.xml_attributes)

        for child in vertical.get_children():
            verify_export_attrs_removed(child.xml_attributes)
            if hasattr(child, 'data'):
                verify_export_attrs_removed(child.data)

    def test_export_course_with_metadata_only_video(self):
        content_store = contentstore()

        import_course_from_xml(self.store, self.user.id, TEST_DATA_DIR, ['toy'], create_if_not_present=True)
        course_id = self.store.make_course_key('edX', 'toy', '2012_Fall')

        # create a new video module and add it as a child to a vertical
        # this re-creates a bug whereby since the video template doesn't have
        # anything in 'data' field, the export was blowing up
        verticals = self.store.get_items(course_id, qualifiers={'category': 'vertical'})

        self.assertGreater(len(verticals), 0)

        parent = verticals[0]

        ItemFactory.create(parent_location=parent.location, category="video", display_name="untitled")

        root_dir = path(mkdtemp_clean())

        print 'Exporting to tempdir = {0}'.format(root_dir)

        # export out to a tempdir
        export_course_to_xml(self.store, content_store, course_id, root_dir, 'test_export')

        shutil.rmtree(root_dir)

    def test_export_course_with_metadata_only_word_cloud(self):
        """
        Similar to `test_export_course_with_metadata_only_video`.
        """
        content_store = contentstore()

        import_course_from_xml(self.store, self.user.id, TEST_DATA_DIR, ['word_cloud'], create_if_not_present=True)
        course_id = self.store.make_course_key('HarvardX', 'ER22x', '2013_Spring')

        verticals = self.store.get_items(course_id, qualifiers={'category': 'vertical'})

        self.assertGreater(len(verticals), 0)

        parent = verticals[0]

        ItemFactory.create(parent_location=parent.location, category="word_cloud", display_name="untitled")

        root_dir = path(mkdtemp_clean())

        print 'Exporting to tempdir = {0}'.format(root_dir)

        # export out to a tempdir
        export_course_to_xml(self.store, content_store, course_id, root_dir, 'test_export')

        shutil.rmtree(root_dir)

    def test_import_after_renaming_xml_data(self):
        """
        Test that import works fine on split mongo after renaming the blocks url.
        """
        split_store = modulestore()._get_modulestore_by_type(ModuleStoreEnum.Type.split)  # pylint: disable=W0212
        import_course_from_xml(
            split_store, self.user.id, TEST_DATA_DIR,
            ['course_before_rename'],
            create_if_not_present=True
        )
        course_after_rename = import_course_from_xml(
            split_store, self.user.id, TEST_DATA_DIR,
            ['course_after_rename'],
            create_if_not_present=True
        )
        all_items = split_store.get_items(course_after_rename[0].id, qualifiers={'category': 'chapter'})
        renamed_chapter = [item for item in all_items if item.location.block_id == 'renamed_chapter'][0]
        self.assertIsNotNone(renamed_chapter.published_on)
        self.assertIsNotNone(renamed_chapter.parent)
        self.assertTrue(renamed_chapter.location in course_after_rename[0].children)
        original_chapter = [item for item in all_items
                            if item.location.block_id == 'b9870b9af59841a49e6e02765d0e3bbf'][0]
        self.assertIsNone(original_chapter.published_on)
        self.assertIsNone(original_chapter.parent)
        self.assertFalse(original_chapter.location in course_after_rename[0].children)

    def test_empty_data_roundtrip(self):
        """
        Test that an empty `data` field is preserved through
        export/import.
        """
        content_store = contentstore()

        import_course_from_xml(self.store, self.user.id, TEST_DATA_DIR, ['toy'], create_if_not_present=True)
        course_id = self.store.make_course_key('edX', 'toy', '2012_Fall')

        verticals = self.store.get_items(course_id, qualifiers={'category': 'vertical'})

        self.assertGreater(len(verticals), 0)

        parent = verticals[0]

        # Create a module, and ensure that its `data` field is empty
        word_cloud = ItemFactory.create(parent_location=parent.location, category="word_cloud", display_name="untitled")
        del word_cloud.data
        self.assertEquals(word_cloud.data, '')

        # Export the course
        root_dir = path(mkdtemp_clean())
        export_course_to_xml(self.store, content_store, course_id, root_dir, 'test_roundtrip')

        # Reimport and get the video back
        import_course_from_xml(self.store, self.user.id, root_dir)
        imported_word_cloud = self.store.get_item(course_id.make_usage_key('word_cloud', 'untitled'))

        # It should now contain empty data
        self.assertEquals(imported_word_cloud.data, '')

    def test_html_export_roundtrip(self):
        """
        Test that a course which has HTML that has style formatting is preserved in export/import
        """
        content_store = contentstore()

        import_course_from_xml(self.store, self.user.id, TEST_DATA_DIR, ['toy'], create_if_not_present=True)

        course_id = self.store.make_course_key('edX', 'toy', '2012_Fall')

        # Export the course
        root_dir = path(mkdtemp_clean())
        export_course_to_xml(self.store, content_store, course_id, root_dir, 'test_roundtrip')

        # Reimport and get the video back
        import_course_from_xml(self.store, self.user.id, root_dir, create_if_not_present=True)

        # get the sample HTML with styling information
        html_module = self.store.get_item(course_id.make_usage_key('html', 'with_styling'))
        self.assertIn('<p style="font:italic bold 72px/30px Georgia, serif; color: red; ">', html_module.data)

        # get the sample HTML with just a simple <img> tag information
        html_module = self.store.get_item(course_id.make_usage_key('html', 'just_img'))
        self.assertIn('<img src="/static/foo_bar.jpg" />', html_module.data)

    def test_export_course_without_content_store(self):
        # Create toy course

        course_items = import_course_from_xml(
            self.store, self.user.id, TEST_DATA_DIR, ['toy'], create_if_not_present=True
        )
        course_id = course_items[0].id

        root_dir = path(mkdtemp_clean())

        print 'Exporting to tempdir = {0}'.format(root_dir)
        export_course_to_xml(self.store, None, course_id, root_dir, 'test_export_no_content_store')

        # Delete the course from module store and reimport it

        self.store.delete_course(course_id, self.user.id)

        import_course_from_xml(
            self.store, self.user.id, root_dir, ['test_export_no_content_store'],
            static_content_store=None,
            target_id=course_id
        )

        # Verify reimported course

        items = self.store.get_items(
            course_id,
            qualifiers={
                'category': 'sequential',
                'name': 'vertical_sequential',
            }
        )
        self.assertEqual(len(items), 1)

    def test_export_course_no_xml_attributes(self):
        """
        Test that a module without an `xml_attributes` attr will still be
        exported successfully
        """
        content_store = contentstore()
        import_course_from_xml(self.store, self.user.id, TEST_DATA_DIR, ['toy'], create_if_not_present=True)
        course_id = self.store.make_course_key('edX', 'toy', '2012_Fall')
        verticals = self.store.get_items(course_id, qualifiers={'category': 'vertical'})
        vertical = verticals[0]

        # create OpenAssessmentBlock:
        open_assessment = ItemFactory.create(
            parent_location=vertical.location,
            category="openassessment",
            display_name="untitled",
        )
        # convert it to draft
        draft_open_assessment = self.store.convert_to_draft(
            open_assessment.location, self.user.id
        )

        # note that it has no `xml_attributes` attribute
        self.assertFalse(hasattr(draft_open_assessment, "xml_attributes"))

        # export should still complete successfully
        root_dir = path(mkdtemp_clean())
        export_course_to_xml(
            self.store,
            content_store,
            course_id,
            root_dir,
            'test_no_xml_attributes'
        )


class MiscCourseTests(ContentStoreTestCase):
    """
    Tests that rely on the toy courses.
    """
    def setUp(self):
        super(MiscCourseTests, self).setUp()
        # save locs not items b/c the items won't have the subsequently created children in them until refetched
        self.chapter_loc = self.store.create_child(
            self.user.id, self.course.location, 'chapter', 'test_chapter'
        ).location
        self.seq_loc = self.store.create_child(
            self.user.id, self.chapter_loc, 'sequential', 'test_seq'
        ).location
        self.vert_loc = self.store.create_child(self.user.id, self.seq_loc, 'vertical', 'test_vert').location
        # now create some things quasi like the toy course had
        self.problem = self.store.create_child(
            self.user.id, self.vert_loc, 'problem', 'test_problem', fields={
                "data": "<problem>Test</problem>"
            }
        )
        self.store.create_child(
            self.user.id, self.vert_loc, 'video', fields={
                "youtube_id_0_75": "JMD_ifUUfsU",
                "youtube_id_1_0": "OEoXaMPEzfM",
                "youtube_id_1_25": "AKqURZnYqpk",
                "youtube_id_1_5": "DYpADpL7jAY",
                "name": "sample_video",
            }
        )
        self.store.create_child(
            self.user.id, self.vert_loc, 'video', fields={
                "youtube_id_0_75": "JMD_ifUUfsU",
                "youtube_id_1_0": "OEoXaMPEzfM",
                "youtube_id_1_25": "AKqURZnYqpk",
                "youtube_id_1_5": "DYpADpL7jAY",
                "name": "truncated_video",
                "end_time": 10.0,
            }
        )
        self.store.create_child(
            self.user.id, self.vert_loc, 'poll_question', fields={
                "name": "T1_changemind_poll_foo_2",
                "display_name": "Change your answer",
                "question": "Have you changed your mind?",
                "answers": [{"id": "yes", "text": "Yes"}, {"id": "no", "text": "No"}],
            }
        )
        self.course = self.store.publish(self.course.location, self.user.id)

    def check_components_on_page(self, component_types, expected_types):
        """
        Ensure that the right types end up on the page.

        component_types is the list of advanced components.

        expected_types is the list of elements that should appear on the page.

        expected_types and component_types should be similar, but not
        exactly the same -- for example, 'video' in
        component_types should cause 'Video' to be present.
        """
        self.course.advanced_modules = component_types
        self.store.update_item(self.course, self.user.id)

        # just pick one vertical
        resp = self.client.get_html(get_url('container_handler', self.vert_loc))
        self.assertEqual(resp.status_code, 200)

        for expected in expected_types:
            self.assertIn(expected, resp.content)

    @patch('django.conf.settings.DEPRECATED_ADVANCED_COMPONENT_TYPES', [])
    def test_advanced_components_in_edit_unit(self):
        # This could be made better, but for now let's just assert that we see the advanced modules mentioned in the page
        # response HTML
        self.check_components_on_page(
            ADVANCED_COMPONENT_TYPES,
            ['Word cloud', 'Annotation', 'Text Annotation', 'Video Annotation', 'Image Annotation',
             'Open Response Assessment', 'Peer Grading Interface', 'split_test'],
        )

    def test_advanced_components_require_two_clicks(self):
        self.check_components_on_page(['word_cloud'], ['Word cloud'])

    def test_malformed_edit_unit_request(self):
        # just pick one vertical
        usage_key = self.course.id.make_usage_key('vertical', None)

        resp = self.client.get_html(get_url('container_handler', usage_key))
        self.assertEqual(resp.status_code, 400)

    def test_edit_unit(self):
        """Verifies rendering the editor in all the verticals in the given test course"""
        self._check_verticals([self.vert_loc])

    def _get_draft_counts(self, item):
        cnt = 1 if getattr(item, 'is_draft', False) else 0
        for child in item.get_children():
            cnt = cnt + self._get_draft_counts(child)

        return cnt

    def test_get_items(self):
        '''
        This verifies a bug we had where the None setting in get_items() meant 'wildcard'
        Unfortunately, None = published for the revision field, so get_items() would return
        both draft and non-draft copies.
        '''
        self.store.convert_to_draft(self.problem.location, self.user.id)

        # Query get_items() and find the html item. This should just return back a single item (not 2).
        direct_store_items = self.store.get_items(
            self.course.id, revision=ModuleStoreEnum.RevisionOption.published_only
        )
        items_from_direct_store = [item for item in direct_store_items if (item.location == self.problem.location)]
        self.assertEqual(len(items_from_direct_store), 1)
        self.assertFalse(getattr(items_from_direct_store[0], 'is_draft', False))

        # Fetch from the draft store.
        draft_store_items = self.store.get_items(
            self.course.id, revision=ModuleStoreEnum.RevisionOption.draft_only
        )
        items_from_draft_store = [item for item in draft_store_items if (item.location == self.problem.location)]
        self.assertEqual(len(items_from_draft_store), 1)
        # TODO the below won't work for split mongo
        self.assertTrue(getattr(items_from_draft_store[0], 'is_draft', False))

    def test_draft_metadata(self):
        '''
        This verifies a bug we had where inherited metadata was getting written to the
        module as 'own-metadata' when publishing. Also verifies the metadata inheritance is
        properly computed
        '''
        # refetch course so it has all the children correct
        course = self.store.update_item(self.course, self.user.id)
        course.graceperiod = timedelta(days=1, hours=5, minutes=59, seconds=59)
        course = self.store.update_item(course, self.user.id)
        problem = self.store.get_item(self.problem.location)

        self.assertEqual(problem.graceperiod, course.graceperiod)
        self.assertNotIn('graceperiod', own_metadata(problem))

        self.store.convert_to_draft(problem.location, self.user.id)

        # refetch to check metadata
        problem = self.store.get_item(problem.location)

        self.assertEqual(problem.graceperiod, course.graceperiod)
        self.assertNotIn('graceperiod', own_metadata(problem))

        # publish module
        self.store.publish(problem.location, self.user.id)

        # refetch to check metadata
        problem = self.store.get_item(problem.location)

        self.assertEqual(problem.graceperiod, course.graceperiod)
        self.assertNotIn('graceperiod', own_metadata(problem))

        # put back in draft and change metadata and see if it's now marked as 'own_metadata'
        self.store.convert_to_draft(problem.location, self.user.id)
        problem = self.store.get_item(problem.location)

        new_graceperiod = timedelta(hours=1)

        self.assertNotIn('graceperiod', own_metadata(problem))
        problem.graceperiod = new_graceperiod
        # Save the data that we've just changed to the underlying
        # MongoKeyValueStore before we update the mongo datastore.
        problem.save()
        self.assertIn('graceperiod', own_metadata(problem))
        self.assertEqual(problem.graceperiod, new_graceperiod)

        self.store.update_item(problem, self.user.id)

        # read back to make sure it reads as 'own-metadata'
        problem = self.store.get_item(problem.location)

        self.assertIn('graceperiod', own_metadata(problem))
        self.assertEqual(problem.graceperiod, new_graceperiod)

        # republish
        self.store.publish(problem.location, self.user.id)

        # and re-read and verify 'own-metadata'
        self.store.convert_to_draft(problem.location, self.user.id)
        problem = self.store.get_item(problem.location)

        self.assertIn('graceperiod', own_metadata(problem))
        self.assertEqual(problem.graceperiod, new_graceperiod)

    def test_get_depth_with_drafts(self):
        # make sure no draft items have been returned
        num_drafts = self._get_draft_counts(self.course)
        self.assertEqual(num_drafts, 0)

        # put into draft
        self.store.convert_to_draft(self.problem.location, self.user.id)

        # make sure we can query that item and verify that it is a draft
        draft_problem = self.store.get_item(self.problem.location)
        self.assertTrue(getattr(draft_problem, 'is_draft', False))

        # now requery with depth
        course = self.store.get_course(self.course.id, depth=None)

        # make sure just one draft item have been returned
        num_drafts = self._get_draft_counts(course)
        self.assertEqual(num_drafts, 1)

    @mock.patch('xmodule.course_module.requests.get')
    def test_import_textbook_as_content_element(self, mock_get):
        mock_get.return_value.text = dedent("""
            <?xml version="1.0"?><table_of_contents>
            <entry page="5" page_label="ii" name="Table of Contents"/>
            </table_of_contents>
        """).strip()
        self.course.textbooks = [Textbook("Textbook", "https://s3.amazonaws.com/edx-textbooks/guttag_computation_v3/")]
        course = self.store.update_item(self.course, self.user.id)
        self.assertGreater(len(course.textbooks), 0)

    def test_import_polls(self):
        items = self.store.get_items(self.course.id, qualifiers={'category': 'poll_question'})
        self.assertTrue(len(items) > 0)
        # check that there's actually content in the 'question' field
        self.assertGreater(len(items[0].question), 0)

    def test_module_preview_in_whitelist(self):
        """
        Tests the ajax callback to render an XModule
        """
        with override_settings(COURSES_WITH_UNSAFE_CODE=[unicode(self.course.id)]):
            # also try a custom response which will trigger the 'is this course in whitelist' logic
            resp = self.client.get_json(
                get_url('xblock_view_handler', self.vert_loc, kwargs={'view_name': 'container_preview'})
            )
            self.assertEqual(resp.status_code, 200)

            vertical = self.store.get_item(self.vert_loc)
            for child in vertical.children:
                self.assertContains(resp, unicode(child))

    def test_delete(self):
        # make sure the parent points to the child object which is to be deleted
        # need to refetch chapter b/c at the time it was assigned it had no children
        chapter = self.store.get_item(self.chapter_loc)
        self.assertIn(self.seq_loc, chapter.children)

        self.client.delete(get_url('xblock_handler', self.seq_loc))

        with self.assertRaises(ItemNotFoundError):
            self.store.get_item(self.seq_loc)

        chapter = self.store.get_item(self.chapter_loc)

        # make sure the parent no longer points to the child object which was deleted
        self.assertNotIn(self.seq_loc, chapter.children)

    def test_asset_delete_and_restore(self):
        '''
        This test will exercise the soft delete/restore functionality of the assets
        '''
        asset_key = self._delete_asset_in_course()

        # now try to find it in store, but they should not be there any longer
        content = contentstore().find(asset_key, throw_on_not_found=False)
        self.assertIsNone(content)

        # now try to find it and the thumbnail in trashcan - should be in there
        content = contentstore('trashcan').find(asset_key, throw_on_not_found=False)
        self.assertIsNotNone(content)

        # let's restore the asset
        restore_asset_from_trashcan(unicode(asset_key))

        # now try to find it in courseware store, and they should be back after restore
        content = contentstore('trashcan').find(asset_key, throw_on_not_found=False)
        self.assertIsNotNone(content)

    def _delete_asset_in_course(self):
        """
        Helper method for:
          1) importing course from xml
          2) finding asset in course (verifying non-empty)
          3) computing thumbnail location of asset
          4) deleting the asset from the course
        """
        asset_key = self.course.id.make_asset_key('asset', 'sample_static.txt')
        content = StaticContent(
            asset_key, "Fake asset", "application/text", "test",
        )
        contentstore().save(content)

        # go through the website to do the delete, since the soft-delete logic is in the view
        url = reverse_course_url(
            'assets_handler',
            self.course.id,
            kwargs={'asset_key_string': unicode(asset_key)}
        )
        resp = self.client.delete(url)
        self.assertEqual(resp.status_code, 204)

        return asset_key

    def test_empty_trashcan(self):
        '''
        This test will exercise the emptying of the asset trashcan
        '''
        self._delete_asset_in_course()

        # make sure there's something in the trashcan
        all_assets, __ = contentstore('trashcan').get_all_content_for_course(self.course.id)
        self.assertGreater(len(all_assets), 0)

        # empty the trashcan
        empty_asset_trashcan([self.course.id])

        # make sure trashcan is empty
        all_assets, count = contentstore('trashcan').get_all_content_for_course(self.course.id)
        self.assertEqual(len(all_assets), 0)
        self.assertEqual(count, 0)

    def test_illegal_draft_crud_ops(self):
        # this test presumes old mongo and split_draft not full split
        with self.assertRaises(InvalidVersionError):
            self.store.convert_to_draft(self.chapter_loc, self.user.id)

        chapter = self.store.get_item(self.chapter_loc)
        chapter.data = 'chapter data'
        self.store.update_item(chapter, self.user.id)
        newobject = self.store.get_item(self.chapter_loc)
        self.assertFalse(getattr(newobject, 'is_draft', False))

        with self.assertRaises(InvalidVersionError):
            self.store.unpublish(self.chapter_loc, self.user.id)

    def test_bad_contentstore_request(self):
        """
        Test that user get proper responses for urls with invalid url or
        asset/course key
        """
        resp = self.client.get_html('/c4x/CDX/123123/asset/&invalid.png')
        self.assertEqual(resp.status_code, 400)

        resp = self.client.get_html('/c4x/CDX/123123/asset/invalid.png')
        self.assertEqual(resp.status_code, 404)

        # Now test that 404 response is returned when user tries to access
        # asset of some invalid course from split ModuleStore
        with self.store.default_store(ModuleStoreEnum.Type.split):
            resp = self.client.get_html('/c4x/InvalidOrg/InvalidCourse/asset/invalid.png')
            self.assertEqual(resp.status_code, 404)

    def test_delete_course(self):
        """
        This test creates a course, makes a draft item, and deletes the course. This will also assert that the
        draft content is also deleted
        """
        # add an asset
        asset_key = self.course.id.make_asset_key('asset', 'sample_static.txt')
        content = StaticContent(
            asset_key, "Fake asset", "application/text", "test",
        )
        contentstore().save(content)
        assets, count = contentstore().get_all_content_for_course(self.course.id)
        self.assertGreater(len(assets), 0)
        self.assertGreater(count, 0)

        self.store.convert_to_draft(self.vert_loc, self.user.id)

        # delete the course
        self.store.delete_course(self.course.id, self.user.id)

        # assert that there's absolutely no non-draft modules in the course
        # this should also include all draft items
        items = self.store.get_items(self.course.id)
        self.assertEqual(len(items), 0)

        # assert that all content in the asset library is also deleted
        assets, count = contentstore().get_all_content_for_course(self.course.id)
        self.assertEqual(len(assets), 0)
        self.assertEqual(count, 0)

    def test_course_handouts_rewrites(self):
        """
        Test that the xblock_handler rewrites static handout links
        """
        handouts = self.store.create_item(
            self.user.id, self.course.id, 'course_info', 'handouts', fields={
                "data": "<a href='/static/handouts/sample_handout.txt'>Sample</a>",
            }
        )

        # get module info (json)
        resp = self.client.get(get_url('xblock_handler', handouts.location))

        # make sure we got a successful response
        self.assertEqual(resp.status_code, 200)
        # check that /static/ has been converted to the full path
        # note, we know the link it should be because that's what in the 'toy' course in the test data
        asset_key = self.course.id.make_asset_key('asset', 'handouts_sample_handout.txt')
        self.assertContains(resp, unicode(asset_key))

    def test_prefetch_children(self):
        # make sure we haven't done too many round trips to DB:
        # 1) the course,
        # 2 & 3) for the chapters and sequentials
        # Because we're querying from the top of the tree, we cache information needed for inheritance,
        # so we don't need to make an extra query to compute it.
        # set the branch to 'publish' in order to prevent extra lookups of draft versions
        with self.store.branch_setting(ModuleStoreEnum.Branch.published_only, self.course.id):
            with check_mongo_calls(3):
                course = self.store.get_course(self.course.id, depth=2)

            # make sure we pre-fetched a known sequential which should be at depth=2
            self.assertIn(self.seq_loc, course.system.module_data)

            # make sure we don't have a specific vertical which should be at depth=3
            self.assertNotIn(self.vert_loc, course.system.module_data)

        # Now, test with the branch set to draft. No extra round trips b/c it doesn't go deep enough to get
        # beyond direct only categories
        with self.store.branch_setting(ModuleStoreEnum.Branch.draft_preferred, self.course.id):
            with check_mongo_calls(3):
                self.store.get_course(self.course.id, depth=2)

    def _check_verticals(self, locations):
        """ Test getting the editing HTML for each vertical. """
        # Assert is here to make sure that the course being tested actually has verticals (units) to check.
        self.assertGreater(len(locations), 0)
        for loc in locations:
            resp = self.client.get_html(get_url('container_handler', loc))
            self.assertEqual(resp.status_code, 200)


@ddt.ddt
class ContentStoreTest(ContentStoreTestCase):
    """
    Tests for the CMS ContentStore application.
    """
    def setUp(self):
        super(ContentStoreTest, self).setUp()

        self.course_data = {
            'org': 'MITx',
            'number': '111',
            'display_name': 'Robot Super Course',
            'run': '2013_Spring'
        }

    def assert_created_course(self, number_suffix=None):
        """
        Checks that the course was created properly.
        """
        test_course_data = {}
        test_course_data.update(self.course_data)
        if number_suffix:
            test_course_data['number'] = '{0}_{1}'.format(test_course_data['number'], number_suffix)
        course_key = _get_course_id(self.store, test_course_data)
        _create_course(self, course_key, test_course_data)
        # Verify that the creator is now registered in the course.
        self.assertTrue(CourseEnrollment.is_enrolled(self.user, course_key))
        return test_course_data

    def assert_create_course_failed(self, error_message):
        """
        Checks that the course not created.
        """
        resp = self.client.ajax_post('/course/', self.course_data)
        self.assertEqual(resp.status_code, 400)
        data = parse_json(resp)
        self.assertEqual(data['error'], error_message)

    def test_create_course(self):
        """Test new course creation - happy path"""
        self.assert_created_course()

    def test_create_course_with_dots(self):
        """Test new course creation with dots in the name"""
        self.course_data['org'] = 'org.foo.bar'
        self.course_data['number'] = 'course.number'
        self.course_data['run'] = 'run.name'
        self.assert_created_course()

    def test_create_course_check_forum_seeding(self):
        """Test new course creation and verify forum seeding """
        test_course_data = self.assert_created_course(number_suffix=uuid4().hex)
        self.assertTrue(are_permissions_roles_seeded(_get_course_id(self.store, test_course_data)))

    def test_forum_unseeding_on_delete(self):
        """Test new course creation and verify forum unseeding """
        test_course_data = self.assert_created_course(number_suffix=uuid4().hex)
        course_id = _get_course_id(self.store, test_course_data)
        self.assertTrue(are_permissions_roles_seeded(course_id))
        delete_course_and_groups(course_id, self.user.id)
        # should raise an exception for checking permissions on deleted course
        with self.assertRaises(ItemNotFoundError):
            are_permissions_roles_seeded(course_id)

    def test_forum_unseeding_with_multiple_courses(self):
        """Test new course creation and verify forum unseeding when there are multiple courses"""
        test_course_data = self.assert_created_course(number_suffix=uuid4().hex)
        second_course_data = self.assert_created_course(number_suffix=uuid4().hex)

        # unseed the forums for the first course
        course_id = _get_course_id(self.store, test_course_data)
        delete_course_and_groups(course_id, self.user.id)
        # should raise an exception for checking permissions on deleted course
        with self.assertRaises(ItemNotFoundError):
            are_permissions_roles_seeded(course_id)

        second_course_id = _get_course_id(self.store, second_course_data)
        # permissions should still be there for the other course
        self.assertTrue(are_permissions_roles_seeded(second_course_id))

    def test_course_enrollments_and_roles_on_delete(self):
        """
        Test that course deletion doesn't remove course enrollments or user's roles
        """
        test_course_data = self.assert_created_course(number_suffix=uuid4().hex)
        course_id = _get_course_id(self.store, test_course_data)

        # test that a user gets his enrollment and its 'student' role as default on creating a course
        self.assertTrue(CourseEnrollment.is_enrolled(self.user, course_id))
        self.assertTrue(self.user.roles.filter(name="Student", course_id=course_id))  # pylint: disable=no-member

        delete_course_and_groups(course_id, self.user.id)
        # check that user's enrollment for this course is not deleted
        self.assertTrue(CourseEnrollment.is_enrolled(self.user, course_id))
        # check that user has form role "Student" for this course even after deleting it
        self.assertTrue(self.user.roles.filter(name="Student", course_id=course_id))  # pylint: disable=no-member

    def test_course_access_groups_on_delete(self):
        """
        Test that course deletion removes users from 'instructor' and 'staff' groups of this course
        of all format e.g, 'instructor_edX/Course/Run', 'instructor_edX.Course.Run', 'instructor_Course'
        """
        test_course_data = self.assert_created_course(number_suffix=uuid4().hex)
        course_id = _get_course_id(self.store, test_course_data)

        # Add user in possible groups and check that user in instructor groups of this course
        instructor_role = CourseInstructorRole(course_id)

        auth.add_users(self.user, instructor_role, self.user)

        self.assertTrue(len(instructor_role.users_with_role()) > 0)

        # Now delete course and check that user not in instructor groups of this course
        delete_course_and_groups(course_id, self.user.id)

        # Update our cached user since its roles have changed
        self.user = User.objects.get_by_natural_key(self.user.natural_key()[0])

        self.assertFalse(instructor_role.has_user(self.user))
        self.assertEqual(len(instructor_role.users_with_role()), 0)

    def test_create_course_duplicate_course(self):
        """Test new course creation - error path"""
        self.client.ajax_post('/course/', self.course_data)
        self.assert_course_creation_failed('There is already a course defined with the same organization and course number. Please change either organization or course number to be unique.')

    def assert_course_creation_failed(self, error_message):
        """
        Checks that the course did not get created
        """
        test_enrollment = False
        try:
            course_id = _get_course_id(self.store, self.course_data)
            initially_enrolled = CourseEnrollment.is_enrolled(self.user, course_id)
            test_enrollment = True
        except InvalidKeyError:
            # b/c the intent of the test with bad chars isn't to test auth but to test the handler, ignore
            pass
        resp = self.client.ajax_post('/course/', self.course_data)
        self.assertEqual(resp.status_code, 200)
        data = parse_json(resp)
        self.assertRegexpMatches(data['ErrMsg'], error_message)
        if test_enrollment:
            # One test case involves trying to create the same course twice. Hence for that course,
            # the user will be enrolled. In the other cases, initially_enrolled will be False.
            self.assertEqual(initially_enrolled, CourseEnrollment.is_enrolled(self.user, course_id))

    def test_create_course_duplicate_number(self):
        """Test new course creation - error path"""
        self.client.ajax_post('/course/', self.course_data)
        self.course_data['display_name'] = 'Robot Super Course Two'
        self.course_data['run'] = '2013_Summer'

        self.assert_course_creation_failed('There is already a course defined with the same organization and course number. Please change either organization or course number to be unique.')

    def test_create_course_case_change(self):
        """Test new course creation - error path due to case insensitive name equality"""
        self.course_data['number'] = 'capital'
        self.client.ajax_post('/course/', self.course_data)
        cache_current = self.course_data['org']
        self.course_data['org'] = self.course_data['org'].lower()
        self.assert_course_creation_failed('There is already a course defined with the same organization and course number. Please change either organization or course number to be unique.')
        self.course_data['org'] = cache_current

        self.client.ajax_post('/course/', self.course_data)
        cache_current = self.course_data['number']
        self.course_data['number'] = self.course_data['number'].upper()
        self.assert_course_creation_failed('There is already a course defined with the same organization and course number. Please change either organization or course number to be unique.')

    def test_course_substring(self):
        """
        Test that a new course can be created whose name is a substring of an existing course
        """
        self.client.ajax_post('/course/', self.course_data)
        cache_current = self.course_data['number']
        self.course_data['number'] = '{}a'.format(self.course_data['number'])
        resp = self.client.ajax_post('/course/', self.course_data)
        self.assertEqual(resp.status_code, 200)
        self.course_data['number'] = cache_current
        self.course_data['org'] = 'a{}'.format(self.course_data['org'])
        resp = self.client.ajax_post('/course/', self.course_data)
        self.assertEqual(resp.status_code, 200)

    def test_create_course_with_bad_organization(self):
        """Test new course creation - error path for bad organization name"""
        self.course_data['org'] = 'University of California, Berkeley'
        self.assert_course_creation_failed(r"(?s)Unable to create course 'Robot Super Course'.*")

    def test_create_course_with_course_creation_disabled_staff(self):
        """Test new course creation -- course creation disabled, but staff access."""
        with mock.patch.dict('django.conf.settings.FEATURES', {'DISABLE_COURSE_CREATION': True}):
            self.assert_created_course()

    def test_create_course_with_course_creation_disabled_not_staff(self):
        """Test new course creation -- error path for course creation disabled, not staff access."""
        with mock.patch.dict('django.conf.settings.FEATURES', {'DISABLE_COURSE_CREATION': True}):
            self.user.is_staff = False
            self.user.save()
            self.assert_course_permission_denied()

    def test_create_course_no_course_creators_staff(self):
        """Test new course creation -- course creation group enabled, staff, group is empty."""
        with mock.patch.dict('django.conf.settings.FEATURES', {'ENABLE_CREATOR_GROUP': True}):
            self.assert_created_course()

    def test_create_course_no_course_creators_not_staff(self):
        """Test new course creation -- error path for course creator group enabled, not staff, group is empty."""
        with mock.patch.dict('django.conf.settings.FEATURES', {"ENABLE_CREATOR_GROUP": True}):
            self.user.is_staff = False
            self.user.save()
            self.assert_course_permission_denied()

    def test_create_course_with_course_creator(self):
        """Test new course creation -- use course creator group"""
        with mock.patch.dict('django.conf.settings.FEATURES', {"ENABLE_CREATOR_GROUP": True}):
            auth.add_users(self.user, CourseCreatorRole(), self.user)
            self.assert_created_course()

    def test_create_course_with_unicode_in_id_disabled(self):
        """
        Test new course creation with feature setting: ALLOW_UNICODE_COURSE_ID disabled.
        """
        with mock.patch.dict('django.conf.settings.FEATURES', {'ALLOW_UNICODE_COURSE_ID': False}):
            error_message = "Special characters not allowed in organization, course number, and course run."
            self.course_data['org'] = u'��������������'
            self.assert_create_course_failed(error_message)

            self.course_data['number'] = u'��chantillon'
            self.assert_create_course_failed(error_message)

            self.course_data['run'] = u'����������'
            self.assert_create_course_failed(error_message)

    def assert_course_permission_denied(self):
        """
        Checks that the course did not get created due to a PermissionError.
        """
        resp = self.client.ajax_post('/course/', self.course_data)
        self.assertEqual(resp.status_code, 403)

    def test_course_index_view_with_no_courses(self):
        """Test viewing the index page with no courses"""
        resp = self.client.get_html('/home/')
        self.assertContains(
            resp,
            '<h1 class="page-header">Studio Home</h1>',
            status_code=200,
            html=True
        )

    def test_course_factory(self):
        """Test that the course factory works correctly."""
        course = CourseFactory.create()
        self.assertIsInstance(course, CourseDescriptor)

    def test_item_factory(self):
        """Test that the item factory works correctly."""
        course = CourseFactory.create()
        item = ItemFactory.create(parent_location=course.location)
        self.assertIsInstance(item, SequenceDescriptor)

    def test_course_index_view_with_course(self):
        """Test viewing the index page with an existing course"""
        CourseFactory.create(display_name='Robot Super Educational Course')
        resp = self.client.get_html('/home/')
        self.assertContains(
            resp,
            '<h3 class="course-title">Robot Super Educational Course</h3>',
            status_code=200,
            html=True
        )

    def test_course_overview_view_with_course(self):
        """Test viewing the course overview page with an existing course"""
        course = CourseFactory.create()
        resp = self._show_course_overview(course.id)
        self.assertContains(
            resp,
            '<article class="outline outline-complex outline-course" data-locator="{locator}" data-course-key="{course_key}">'.format(
                locator=unicode(course.location),
                course_key=unicode(course.id),
            ),
            status_code=200,
            html=True
        )

    def test_create_item(self):
        """Test creating a new xblock instance."""
        course = CourseFactory.create()

        section_data = {
            'parent_locator': unicode(course.location),
            'category': 'chapter',
            'display_name': 'Section One',
        }

        resp = self.client.ajax_post(reverse_url('xblock_handler'), section_data)

        self.assertEqual(resp.status_code, 200)
        data = parse_json(resp)
        retarget = unicode(course.id.make_usage_key('chapter', 'REPLACE')).replace('REPLACE', r'([0-9]|[a-f]){3,}')
        self.assertRegexpMatches(data['locator'], retarget)

    def test_capa_module(self):
        """Test that a problem treats markdown specially."""
        course = CourseFactory.create()

        problem_data = {
            'parent_locator': unicode(course.location),
            'category': 'problem'
        }

        resp = self.client.ajax_post(reverse_url('xblock_handler'), problem_data)
        self.assertEqual(resp.status_code, 200)
        payload = parse_json(resp)
        problem_loc = UsageKey.from_string(payload['locator'])
        problem = self.store.get_item(problem_loc)
        # should be a CapaDescriptor
        self.assertIsInstance(problem, CapaDescriptor, "New problem is not a CapaDescriptor")
        context = problem.get_context()
        self.assertIn('markdown', context, "markdown is missing from context")
        self.assertNotIn('markdown', problem.editable_metadata_fields, "Markdown slipped into the editable metadata fields")

    def test_cms_imported_course_walkthrough(self):
        """
        Import and walk through some common URL endpoints. This just verifies non-500 and no other
        correct behavior, so it is not a deep test
        """
        def test_get_html(handler):
            # Helper function for getting HTML for a page in Studio and
            # checking that it does not error.
            resp = self.client.get_html(
                get_url(handler, course_key, 'course_key_string')
            )
            self.assertEqual(resp.status_code, 200)

        course_items = import_course_from_xml(
            self.store, self.user.id, TEST_DATA_DIR, ['simple'], create_if_not_present=True
        )
        course_key = course_items[0].id

        resp = self._show_course_overview(course_key)
        self.assertEqual(resp.status_code, 200)
        self.assertContains(resp, 'Chapter 2')

        # go to various pages
        test_get_html('import_handler')
        test_get_html('export_handler')
        test_get_html('course_team_handler')
        test_get_html('course_info_handler')
        test_get_html('checklists_handler')
        test_get_html('assets_handler')
        test_get_html('tabs_handler')
        test_get_html('settings_handler')
        test_get_html('grading_handler')
        test_get_html('advanced_settings_handler')
        test_get_html('textbooks_list_handler')

        # go look at the Edit page
        unit_key = course_key.make_usage_key('vertical', 'test_vertical')
        resp = self.client.get_html(get_url('container_handler', unit_key))
        self.assertEqual(resp.status_code, 200)

        def delete_item(category, name):
            """ Helper method for testing the deletion of an xblock item. """
            item_key = course_key.make_usage_key(category, name)
            resp = self.client.delete(get_url('xblock_handler', item_key))
            self.assertEqual(resp.status_code, 204)

        # delete a component
        delete_item(category='html', name='test_html')

        # delete a unit
        delete_item(category='vertical', name='test_vertical')

        # delete a unit
        delete_item(category='sequential', name='test_sequence')

        # delete a chapter
        delete_item(category='chapter', name='chapter_2')

    def test_import_into_new_course_id(self):
        target_id = _get_course_id(self.store, self.course_data)
        _create_course(self, target_id, self.course_data)

        import_course_from_xml(self.store, self.user.id, TEST_DATA_DIR, ['toy'], target_id=target_id)

        modules = self.store.get_items(target_id)

        # we should have a number of modules in there
        # we can't specify an exact number since it'll always be changing
        self.assertGreater(len(modules), 10)

        #
        # test various re-namespacing elements
        #

        # first check PDF textbooks, to make sure the url paths got updated
        course_module = self.store.get_course(target_id)

        self.assertEqual(len(course_module.pdf_textbooks), 1)
        self.assertEqual(len(course_module.pdf_textbooks[0]["chapters"]), 2)
        self.assertEqual(course_module.pdf_textbooks[0]["chapters"][0]["url"], '/static/Chapter1.pdf')
        self.assertEqual(course_module.pdf_textbooks[0]["chapters"][1]["url"], '/static/Chapter2.pdf')

    def test_import_into_new_course_id_wiki_slug_renamespacing(self):
        # If reimporting into the same course do not change the wiki_slug.
        target_id = self.store.make_course_key('edX', 'toy', '2012_Fall')
        course_data = {
            'org': target_id.org,
            'number': target_id.course,
            'display_name': 'Robot Super Course',
            'run': target_id.run
        }
        _create_course(self, target_id, course_data)
        course_module = self.store.get_course(target_id)
        course_module.wiki_slug = 'toy'
        course_module.save()

        # Import a course with wiki_slug == location.course
        import_course_from_xml(self.store, self.user.id, TEST_DATA_DIR, ['toy'], target_id=target_id)
        course_module = self.store.get_course(target_id)
        self.assertEquals(course_module.wiki_slug, 'toy')

        # But change the wiki_slug if it is a different course.
        target_id = self.store.make_course_key('MITx', '111', '2013_Spring')
        course_data = {
            'org': target_id.org,
            'number': target_id.course,
            'display_name': 'Robot Super Course',
            'run': target_id.run
        }
        _create_course(self, target_id, course_data)

        # Import a course with wiki_slug == location.course
        import_course_from_xml(self.store, self.user.id, TEST_DATA_DIR, ['toy'], target_id=target_id)
        course_module = self.store.get_course(target_id)
        self.assertEquals(course_module.wiki_slug, 'MITx.111.2013_Spring')

        # Now try importing a course with wiki_slug == '{0}.{1}.{2}'.format(location.org, location.course, location.run)
        import_course_from_xml(self.store, self.user.id, TEST_DATA_DIR, ['two_toys'], target_id=target_id)
        course_module = self.store.get_course(target_id)
        self.assertEquals(course_module.wiki_slug, 'MITx.111.2013_Spring')

    def test_import_metadata_with_attempts_empty_string(self):
        import_course_from_xml(self.store, self.user.id, TEST_DATA_DIR, ['simple'], create_if_not_present=True)
        did_load_item = False
        try:
            course_key = self.store.make_course_key('edX', 'simple', 'problem')
            usage_key = course_key.make_usage_key('problem', 'ps01-simple')
            self.store.get_item(usage_key)
            did_load_item = True
        except ItemNotFoundError:
            pass

        # make sure we found the item (e.g. it didn't error while loading)
        self.assertTrue(did_load_item)

    @ddt.data(ModuleStoreEnum.Type.split, ModuleStoreEnum.Type.mongo)
    def test_forum_id_generation(self, default_store):
        """
        Test that a discussion item, even if it doesn't set its discussion_id,
        consistently generates the same one
        """
        course = CourseFactory.create(default_store=default_store)

        # create a discussion item
        discussion_item = self.store.create_item(self.user.id, course.id, 'discussion', 'new_component')

        # now fetch it from the modulestore to instantiate its descriptor
        fetched = self.store.get_item(discussion_item.location)

        # refetch it to be safe
        refetched = self.store.get_item(discussion_item.location)

        # and make sure the same discussion items have the same discussion ids
        self.assertEqual(fetched.discussion_id, discussion_item.discussion_id)
        self.assertEqual(fetched.discussion_id, refetched.discussion_id)

        # and make sure that the id isn't the old "$$GUID$$"
        self.assertNotEqual(discussion_item.discussion_id, '$$GUID$$')

    def test_metadata_inheritance(self):
        course_items = import_course_from_xml(
            self.store, self.user.id, TEST_DATA_DIR, ['toy'], create_if_not_present=True
        )

        course = course_items[0]
        verticals = self.store.get_items(course.id, qualifiers={'category': 'vertical'})

        # let's assert on the metadata_inheritance on an existing vertical
        for vertical in verticals:
            self.assertEqual(course.xqa_key, vertical.xqa_key)
            self.assertEqual(course.start, vertical.start)

        self.assertGreater(len(verticals), 0)

        # crate a new module and add it as a child to a vertical
        parent = verticals[0]
        new_block = self.store.create_child(
            self.user.id, parent.location, 'html', 'new_component'
        )

        # flush the cache
        new_block = self.store.get_item(new_block.location)

        # check for grace period definition which should be defined at the course level
        self.assertEqual(parent.graceperiod, new_block.graceperiod)
        self.assertEqual(parent.start, new_block.start)
        self.assertEqual(course.start, new_block.start)

        self.assertEqual(course.xqa_key, new_block.xqa_key)

        #
        # now let's define an override at the leaf node level
        #
        new_block.graceperiod = timedelta(1)
        self.store.update_item(new_block, self.user.id)

        # flush the cache and refetch
        new_block = self.store.get_item(new_block.location)

        self.assertEqual(timedelta(1), new_block.graceperiod)

    def test_default_metadata_inheritance(self):
        course = CourseFactory.create()
        vertical = ItemFactory.create(parent_location=course.location)
        course.children.append(vertical)
        # in memory
        self.assertIsNotNone(course.start)
        self.assertEqual(course.start, vertical.start)
        self.assertEqual(course.textbooks, [])
        self.assertIn('GRADER', course.grading_policy)
        self.assertIn('GRADE_CUTOFFS', course.grading_policy)
        self.assertGreaterEqual(len(course.checklists), 4)

        # by fetching
        fetched_course = self.store.get_item(course.location)
        fetched_item = self.store.get_item(vertical.location)
        self.assertIsNotNone(fetched_course.start)
        self.assertEqual(course.start, fetched_course.start)
        self.assertEqual(fetched_course.start, fetched_item.start)
        self.assertEqual(course.textbooks, fetched_course.textbooks)
        # is this test too strict? i.e., it requires the dicts to be ==
        self.assertEqual(course.checklists, fetched_course.checklists)

    def test_image_import(self):
        """Test backwards compatibilty of course image."""
        content_store = contentstore()

        # Use conditional_and_poll, as it's got an image already
        courses = import_course_from_xml(
            self.store,
            self.user.id,
            TEST_DATA_DIR,
            ['conditional_and_poll'],
            static_content_store=content_store,
            create_if_not_present=True
        )

        course = courses[0]

        # Make sure the course image is set to the right place
        self.assertEqual(course.course_image, 'images_course_image.jpg')

        # Ensure that the imported course image is present -- this shouldn't raise an exception
        asset_key = course.id.make_asset_key('asset', course.course_image)
        content_store.find(asset_key)

    def _show_course_overview(self, course_key):
        """
        Show the course overview page.
        """
        resp = self.client.get_html(get_url('course_handler', course_key, 'course_key_string'))
        return resp

    def test_wiki_slug(self):
        """When creating a course a unique wiki_slug should be set."""

        course_key = _get_course_id(self.store, self.course_data)
        _create_course(self, course_key, self.course_data)
        course_module = self.store.get_course(course_key)
        self.assertEquals(course_module.wiki_slug, 'MITx.111.2013_Spring')

    def test_course_handler_with_invalid_course_key_string(self):
        """Test viewing the course overview page with invalid course id"""

        response = self.client.get_html('/course/edX/test')
        self.assertEquals(response.status_code, 404)


class MetadataSaveTestCase(ContentStoreTestCase):
    """Test that metadata is correctly cached and decached."""

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

        course = CourseFactory.create()

        video_sample_xml = '''
        <video display_name="Test Video"
                youtube="1.0:p2Q6BrNhdh8,0.75:izygArpw-Qo,1.25:1EeWXzPdhSA,1.5:rABDYkeK0x8"
                show_captions="false"
                from="00:00:01"
                to="00:01:00">
            <source src="http://www.example.com/file.mp4"/>
            <track src="http://www.example.com/track"/>
        </video>
        '''
        self.video_descriptor = ItemFactory.create(
            parent_location=course.location, category='video',
            data={'data': video_sample_xml}
        )

    def test_metadata_not_persistence(self):
        """
        Test that descriptors which set metadata fields in their
        constructor are correctly deleted.
        """
        self.assertIn('html5_sources', own_metadata(self.video_descriptor))
        attrs_to_strip = {
            'show_captions',
            'youtube_id_1_0',
            'youtube_id_0_75',
            'youtube_id_1_25',
            'youtube_id_1_5',
            'start_time',
            'end_time',
            'source',
            'html5_sources',
            'track'
        }

        location = self.video_descriptor.location

        for field_name in attrs_to_strip:
            delattr(self.video_descriptor, field_name)

        self.assertNotIn('html5_sources', own_metadata(self.video_descriptor))
        self.store.update_item(self.video_descriptor, self.user.id)
        module = self.store.get_item(location)

        self.assertNotIn('html5_sources', own_metadata(module))

    def test_metadata_persistence(self):
        # TODO: create the same test as `test_metadata_not_persistence`,
        # but check persistence for some other module.
        pass


class RerunCourseTest(ContentStoreTestCase):
    """
    Tests for Rerunning a course via the view handler
    """
    def setUp(self):
        super(RerunCourseTest, self).setUp()
        self.destination_course_data = {
            'org': 'MITx',
            'number': '111',
            'display_name': 'Robot Super Course',
            'run': '2013_Spring'
        }

    def post_rerun_request(
            self, source_course_key, destination_course_data=None, response_code=200, expect_error=False
    ):
        """Create and send an ajax post for the rerun request"""

        # create data to post
        rerun_course_data = {'source_course_key': unicode(source_course_key)}
        if not destination_course_data:
            destination_course_data = self.destination_course_data
        rerun_course_data.update(destination_course_data)
        destination_course_key = _get_course_id(self.store, destination_course_data)

        # post the request
        course_url = get_url('course_handler', destination_course_key, 'course_key_string')
        response = self.client.ajax_post(course_url, rerun_course_data)

        # verify response
        self.assertEqual(response.status_code, response_code)
        if not expect_error:
            json_resp = parse_json(response)
            self.assertNotIn('ErrMsg', json_resp)
            destination_course_key = CourseKey.from_string(json_resp['destination_course_key'])
        return destination_course_key

    def get_course_listing_elements(self, html, course_key):
        """Returns the elements in the course listing section of html that have the given course_key"""
        return html.cssselect('.course-item[data-course-key="{}"]'.format(unicode(course_key)))

    def get_unsucceeded_course_action_elements(self, html, course_key):
        """Returns the elements in the unsucceeded course action section that have the given course_key"""
        return html.cssselect('.courses-processing li[data-course-key="{}"]'.format(unicode(course_key)))

    def assertInCourseListing(self, course_key):
        """
        Asserts that the given course key is in the accessible course listing section of the html
        and NOT in the unsucceeded course action section of the html.
        """
        course_listing = lxml.html.fromstring(self.client.get_html('/home/').content)
        self.assertEqual(len(self.get_course_listing_elements(course_listing, course_key)), 1)
        self.assertEqual(len(self.get_unsucceeded_course_action_elements(course_listing, course_key)), 0)

    def assertInUnsucceededCourseActions(self, course_key):
        """
        Asserts that the given course key is in the unsucceeded course action section of the html
        and NOT in the accessible course listing section of the html.
        """
        course_listing = lxml.html.fromstring(self.client.get_html('/home/').content)
        self.assertEqual(len(self.get_course_listing_elements(course_listing, course_key)), 0)
        self.assertEqual(len(self.get_unsucceeded_course_action_elements(course_listing, course_key)), 1)

    def verify_rerun_course(self, source_course_key, destination_course_key, destination_display_name):
        """
        Verify the contents of the course rerun action
        """
        rerun_state = CourseRerunState.objects.find_first(course_key=destination_course_key)
        expected_states = {
            'state': CourseRerunUIStateManager.State.SUCCEEDED,
            'display_name': destination_display_name,
            'source_course_key': source_course_key,
            'course_key': destination_course_key,
            'should_display': True,
        }
        for field_name, expected_value in expected_states.iteritems():
            self.assertEquals(getattr(rerun_state, field_name), expected_value)

        # Verify that the creator is now enrolled in the course.
        self.assertTrue(CourseEnrollment.is_enrolled(self.user, destination_course_key))

        # Verify both courses are in the course listing section
        self.assertInCourseListing(source_course_key)
        self.assertInCourseListing(destination_course_key)

    def test_rerun_course_no_videos_in_val(self):
        """
        Test when rerunning a course with no videos, VAL copies nothing
        """
        source_course = CourseFactory.create()
        destination_course_key = self.post_rerun_request(source_course.id)
        self.verify_rerun_course(source_course.id, destination_course_key, self.destination_course_data['display_name'])
        videos = list(get_videos_for_course(destination_course_key))
        self.assertEqual(0, len(videos))
        self.assertInCourseListing(destination_course_key)

    def test_rerun_course_success(self):
        source_course = CourseFactory.create()
        create_video(
            dict(
                edx_video_id="tree-hugger",
                courses=[source_course.id],
                status='test',
                duration=2,
                encoded_videos=[]
            )
        )
        destination_course_key = self.post_rerun_request(source_course.id)
        self.verify_rerun_course(source_course.id, destination_course_key, self.destination_course_data['display_name'])

        # Verify that the VAL copies videos to the rerun
        source_videos = list(get_videos_for_course(source_course.id))
        target_videos = list(get_videos_for_course(destination_course_key))
        self.assertEqual(1, len(source_videos))
        self.assertEqual(source_videos, target_videos)

    def test_rerun_of_rerun(self):
        source_course = CourseFactory.create()
        rerun_course_key = self.post_rerun_request(source_course.id)
        rerun_of_rerun_data = {
            'org': rerun_course_key.org,
            'number': rerun_course_key.course,
            'display_name': 'rerun of rerun',
            'run': 'rerun2'
        }
        rerun_of_rerun_course_key = self.post_rerun_request(rerun_course_key, rerun_of_rerun_data)
        self.verify_rerun_course(rerun_course_key, rerun_of_rerun_course_key, rerun_of_rerun_data['display_name'])

    def test_rerun_course_fail_no_source_course(self):
        existent_course_key = CourseFactory.create().id
        non_existent_course_key = CourseLocator("org", "non_existent_course", "non_existent_run")
        destination_course_key = self.post_rerun_request(non_existent_course_key)

        # Verify that the course rerun action is marked failed
        rerun_state = CourseRerunState.objects.find_first(course_key=destination_course_key)
        self.assertEquals(rerun_state.state, CourseRerunUIStateManager.State.FAILED)
        self.assertIn("Cannot find a course at", rerun_state.message)

        # Verify that the creator is not enrolled in the course.
        self.assertFalse(CourseEnrollment.is_enrolled(self.user, non_existent_course_key))

        # Verify that the existing course continues to be in the course listings
        self.assertInCourseListing(existent_course_key)

        # Verify that the failed course is NOT in the course listings
        self.assertInUnsucceededCourseActions(destination_course_key)

    def test_rerun_course_fail_duplicate_course(self):
        existent_course_key = CourseFactory.create().id
        destination_course_data = {
            'org': existent_course_key.org,
            'number': existent_course_key.course,
            'display_name': 'existing course',
            'run': existent_course_key.run
        }
        destination_course_key = self.post_rerun_request(
            existent_course_key, destination_course_data, expect_error=True
        )

        # Verify that the course rerun action doesn't exist
        with self.assertRaises(CourseActionStateItemNotFoundError):
            CourseRerunState.objects.find_first(course_key=destination_course_key)

        # Verify that the existing course continues to be in the course listing
        self.assertInCourseListing(existent_course_key)

    def test_rerun_with_permission_denied(self):
        with mock.patch.dict('django.conf.settings.FEATURES', {"ENABLE_CREATOR_GROUP": True}):
            source_course = CourseFactory.create()
            auth.add_users(self.user, CourseCreatorRole(), self.user)
            self.user.is_staff = False
            self.user.save()
            self.post_rerun_request(source_course.id, response_code=403, expect_error=True)

    def test_rerun_error(self):
        error_message = "Mock Error Message"
        with mock.patch(
                'xmodule.modulestore.mixed.MixedModuleStore.clone_course',
                mock.Mock(side_effect=Exception(error_message))
        ):
            source_course = CourseFactory.create()
            destination_course_key = self.post_rerun_request(source_course.id)
            rerun_state = CourseRerunState.objects.find_first(course_key=destination_course_key)
            self.assertEquals(rerun_state.state, CourseRerunUIStateManager.State.FAILED)
            self.assertIn(error_message, rerun_state.message)

    def test_rerun_error_trunc_message(self):
        """
        CourseActionUIState.message is sometimes populated with the contents
        of Python tracebacks. This test ensures we don't crash when attempting
        to insert a value exceeding its max_length (note that sqlite does not
        complain if this happens, but MySQL throws an error).
        """
        with mock.patch(
            'xmodule.modulestore.mixed.MixedModuleStore.clone_course',
            mock.Mock(side_effect=Exception()),
        ):
            source_course = CourseFactory.create()
            message_too_long = "traceback".rjust(CourseRerunState.MAX_MESSAGE_LENGTH * 2, '-')
            with mock.patch('traceback.format_exc', return_value=message_too_long):
                destination_course_key = self.post_rerun_request(source_course.id)
            rerun_state = CourseRerunState.objects.find_first(course_key=destination_course_key)
            self.assertEquals(rerun_state.state, CourseRerunUIStateManager.State.FAILED)
            self.assertTrue(rerun_state.message.endswith("traceback"))
            self.assertEqual(len(rerun_state.message), CourseRerunState.MAX_MESSAGE_LENGTH)


class ContentLicenseTest(ContentStoreTestCase):
    """
    Tests around content licenses
    """
    def test_course_license_export(self):
        content_store = contentstore()
        root_dir = path(mkdtemp_clean())
        self.course.license = "creative-commons: BY SA"
        self.store.update_item(self.course, None)
        export_course_to_xml(self.store, content_store, self.course.id, root_dir, 'test_license')
        fname = "{block}.xml".format(block=self.course.scope_ids.usage_id.block_id)
        run_file_path = root_dir / "test_license" / "course" / fname
        run_xml = etree.parse(run_file_path.open())
        self.assertEqual(run_xml.getroot().get("license"), "creative-commons: BY SA")

    def test_video_license_export(self):
        content_store = contentstore()
        root_dir = path(mkdtemp_clean())
        video_descriptor = ItemFactory.create(
            parent_location=self.course.location, category='video',
            license="all-rights-reserved"
        )
        export_course_to_xml(self.store, content_store, self.course.id, root_dir, 'test_license')
        fname = "{block}.xml".format(block=video_descriptor.scope_ids.usage_id.block_id)
        video_file_path = root_dir / "test_license" / "video" / fname
        video_xml = etree.parse(video_file_path.open())
        self.assertEqual(video_xml.getroot().get("license"), "all-rights-reserved")

    def test_license_import(self):
        course_items = import_course_from_xml(
            self.store, self.user.id, TEST_DATA_DIR, ['toy'], create_if_not_present=True
        )
        course = course_items[0]
        self.assertEqual(course.license, "creative-commons: BY")
        videos = self.store.get_items(course.id, qualifiers={'category': 'video'})
        self.assertEqual(videos[0].license, "all-rights-reserved")


class EntryPageTestCase(TestCase):
    """
    Tests entry pages that aren't specific to a course.
    """
    def setUp(self):
        super(EntryPageTestCase, self).setUp()
        self.client = AjaxEnabledTestClient()

    def _test_page(self, page, status_code=200):
        resp = self.client.get_html(page)
        self.assertEqual(resp.status_code, status_code)

    def test_how_it_works(self):
        self._test_page("/howitworks")

    def test_signup(self):
        self._test_page("/signup")

    def test_login(self):
        self._test_page("/signin")

    def test_logout(self):
        # Logout redirects.
        self._test_page("/logout", 302)


class SigninPageTestCase(TestCase):
    """
    Tests that the CSRF token is directly included in the signin form. This is
    important to make sure that the script is functional independently of any
    other script.
    """

    def test_csrf_token_is_present_in_form(self):
        # Expected html:
        # <form>
        #   ...
        #   <fieldset>
        #       ...
        #       <input name="csrfmiddlewaretoken" value="...">
        #       ...
        #       </fieldset>
        #       ...
        #</form>
        response = self.client.get("/signin")
        csrf_token = response.cookies.get("csrftoken")
        form = lxml.html.fromstring(response.content).get_element_by_id("login_form")
        csrf_input_field = form.find(".//input[@name='csrfmiddlewaretoken']")

        self.assertIsNotNone(csrf_token)
        self.assertIsNotNone(csrf_token.value)
        self.assertIsNotNone(csrf_input_field)
        self.assertEqual(csrf_token.value, csrf_input_field.attrib["value"])


def _create_course(test, course_key, course_data):
    """
    Creates a course via an AJAX request and verifies the URL returned in the response.
    """
    course_url = get_url('course_handler', course_key, 'course_key_string')
    response = test.client.ajax_post(course_url, course_data)
    test.assertEqual(response.status_code, 200)
    data = parse_json(response)
    test.assertNotIn('ErrMsg', data)
    test.assertEqual(data['url'], course_url)


def _get_course_id(store, course_data):
    """Returns the course ID."""
    return store.make_course_key(course_data['org'], course_data['number'], course_data['run'])
