"""Tests for items views."""

import copy
import json
import os
import tempfile
import textwrap
from uuid import uuid4
from mock import patch

from django.core.urlresolvers import reverse
from django.test.utils import override_settings
from django.conf import settings

from contentstore.tests.utils import CourseTestCase, mock_requests_get
from cache_toolbox.core import del_cached_content
from xmodule.modulestore.django import modulestore
from xmodule.contentstore.django import contentstore
from xmodule.contentstore.content import StaticContent
from xmodule.exceptions import NotFoundError
from opaque_keys.edx.keys import UsageKey
from xmodule.video_module import transcripts_utils

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


@override_settings(CONTENTSTORE=TEST_DATA_CONTENTSTORE)
class BaseTranscripts(CourseTestCase):
    """Base test class for transcripts tests."""

    def clear_subs_content(self):
        """Remove, if transcripts content exists."""
        for youtube_id in self.get_youtube_ids().values():
            filename = 'subs_{0}.srt.sjson'.format(youtube_id)
            content_location = StaticContent.compute_location(self.course.id, filename)
            try:
                content = contentstore().find(content_location)
                contentstore().delete(content.get_id())
            except NotFoundError:
                pass

    def setUp(self):
        """Create initial data."""
        super(BaseTranscripts, self).setUp()

        # Add video module
        data = {
            'parent_locator': unicode(self.course.location),
            'category': 'video',
            'type': 'video'
        }
        resp = self.client.ajax_post('/xblock/', data)
        self.assertEqual(resp.status_code, 200)

        self.video_usage_key = self._get_usage_key(resp)
        self.item = modulestore().get_item(self.video_usage_key)
        # hI10vDNYz4M - valid Youtube ID with transcripts.
        # JMD_ifUUfsU, AKqURZnYqpk, DYpADpL7jAY - valid Youtube IDs without transcripts.
        self.item.data = '<video youtube="0.75:JMD_ifUUfsU,1.0:hI10vDNYz4M,1.25:AKqURZnYqpk,1.50:DYpADpL7jAY" />'
        modulestore().update_item(self.item, self.user.id)

        self.item = modulestore().get_item(self.video_usage_key)
        # Remove all transcripts for current module.
        self.clear_subs_content()

    def _get_usage_key(self, resp):
        """ Returns the usage key from the response returned by a create operation. """
        usage_key_string = json.loads(resp.content).get('locator')
        return UsageKey.from_string(usage_key_string)

    def get_youtube_ids(self):
        """Return youtube speeds and ids."""
        item = modulestore().get_item(self.video_usage_key)

        return {
            0.75: item.youtube_id_0_75,
            1: item.youtube_id_1_0,
            1.25: item.youtube_id_1_25,
            1.5: item.youtube_id_1_5
        }


class TestUploadTranscripts(BaseTranscripts):
    """Tests for '/transcripts/upload' url."""

    def setUp(self):
        """Create initial data."""
        super(TestUploadTranscripts, self).setUp()

        self.good_srt_file = tempfile.NamedTemporaryFile(suffix='.srt')
        self.good_srt_file.write(textwrap.dedent("""
            1
            00:00:10,500 --> 00:00:13,000
            Elephant's Dream

            2
            00:00:15,000 --> 00:00:18,000
            At the left we can see...
        """))
        self.good_srt_file.seek(0)

        self.bad_data_srt_file = tempfile.NamedTemporaryFile(suffix='.srt')
        self.bad_data_srt_file.write('Some BAD data')
        self.bad_data_srt_file.seek(0)

        self.bad_name_srt_file = tempfile.NamedTemporaryFile(suffix='.BAD')
        self.bad_name_srt_file.write(textwrap.dedent("""
            1
            00:00:10,500 --> 00:00:13,000
            Elephant's Dream

            2
            00:00:15,000 --> 00:00:18,000
            At the left we can see...
        """))
        self.bad_name_srt_file.seek(0)

        self.ufeff_srt_file = tempfile.NamedTemporaryFile(suffix='.srt')

    def test_success_video_module_source_subs_uploading(self):
        self.item.data = textwrap.dedent("""
            <video youtube="">
                <source src="http://www.quirksmode.org/html5/videos/big_buck_bunny.mp4"/>
                <source src="http://www.quirksmode.org/html5/videos/big_buck_bunny.webm"/>
                <source src="http://www.quirksmode.org/html5/videos/big_buck_bunny.ogv"/>
            </video>
        """)
        modulestore().update_item(self.item, self.user.id)

        link = reverse('upload_transcripts')
        filename = os.path.splitext(os.path.basename(self.good_srt_file.name))[0]
        resp = self.client.post(link, {
            'locator': self.video_usage_key,
            'transcript-file': self.good_srt_file,
            'video_list': json.dumps([{
                'type': 'html5',
                'video': filename,
                'mode': 'mp4',
            }])
        })
        self.assertEqual(resp.status_code, 200)
        self.assertEqual(json.loads(resp.content).get('status'), 'Success')

        item = modulestore().get_item(self.video_usage_key)
        self.assertEqual(item.sub, filename)

        content_location = StaticContent.compute_location(
            self.course.id, 'subs_{0}.srt.sjson'.format(filename))
        self.assertTrue(contentstore().find(content_location))

    def test_fail_data_without_id(self):
        link = reverse('upload_transcripts')
        resp = self.client.post(link, {'transcript-file': self.good_srt_file})
        self.assertEqual(resp.status_code, 400)
        self.assertEqual(json.loads(resp.content).get('status'), 'POST data without "locator" form data.')

    def test_fail_data_without_file(self):
        link = reverse('upload_transcripts')
        resp = self.client.post(link, {'locator': self.video_usage_key})
        self.assertEqual(resp.status_code, 400)
        self.assertEqual(json.loads(resp.content).get('status'), 'POST data without "file" form data.')

    def test_fail_data_with_bad_locator(self):
        # Test for raising `InvalidLocationError` exception.
        link = reverse('upload_transcripts')
        filename = os.path.splitext(os.path.basename(self.good_srt_file.name))[0]
        resp = self.client.post(link, {
            'locator': 'BAD_LOCATOR',
            'transcript-file': self.good_srt_file,
            'video_list': json.dumps([{
                'type': 'html5',
                'video': filename,
                'mode': 'mp4',
            }])
        })
        self.assertEqual(resp.status_code, 400)
        self.assertEqual(json.loads(resp.content).get('status'), "Can't find item by locator.")

        # Test for raising `ItemNotFoundError` exception.
        link = reverse('upload_transcripts')
        filename = os.path.splitext(os.path.basename(self.good_srt_file.name))[0]
        resp = self.client.post(link, {
            'locator': '{0}_{1}'.format(self.video_usage_key, 'BAD_LOCATOR'),
            'transcript-file': self.good_srt_file,
            'video_list': json.dumps([{
                'type': 'html5',
                'video': filename,
                'mode': 'mp4',
            }])
        })
        self.assertEqual(resp.status_code, 400)
        self.assertEqual(json.loads(resp.content).get('status'), "Can't find item by locator.")

    def test_fail_for_non_video_module(self):
        # non_video module: setup
        data = {
            'parent_locator': unicode(self.course.location),
            'category': 'non_video',
            'type': 'non_video'
        }
        resp = self.client.ajax_post('/xblock/', data)
        usage_key = self._get_usage_key(resp)
        item = modulestore().get_item(usage_key)
        item.data = '<non_video youtube="0.75:JMD_ifUUfsU,1.0:hI10vDNYz4M" />'
        modulestore().update_item(item, self.user.id)

        # non_video module: testing

        link = reverse('upload_transcripts')
        filename = os.path.splitext(os.path.basename(self.good_srt_file.name))[0]
        resp = self.client.post(link, {
            'locator': unicode(usage_key),
            'transcript-file': self.good_srt_file,
            'video_list': json.dumps([{
                'type': 'html5',
                'video': filename,
                'mode': 'mp4',
            }])
        })
        self.assertEqual(resp.status_code, 400)
        self.assertEqual(json.loads(resp.content).get('status'), 'Transcripts are supported only for "video" modules.')

    def test_fail_bad_xml(self):
        self.item.data = '<<<video youtube="0.75:JMD_ifUUfsU,1.25:AKqURZnYqpk,1.50:DYpADpL7jAY" />'
        modulestore().update_item(self.item, self.user.id)

        link = reverse('upload_transcripts')
        filename = os.path.splitext(os.path.basename(self.good_srt_file.name))[0]
        resp = self.client.post(link, {
            'locator': unicode(self.video_usage_key),
            'transcript-file': self.good_srt_file,
            'video_list': json.dumps([{
                'type': 'html5',
                'video': filename,
                'mode': 'mp4',
            }])
        })

        self.assertEqual(resp.status_code, 400)
        # incorrect xml produces incorrect item category error
        self.assertEqual(json.loads(resp.content).get('status'), 'Transcripts are supported only for "video" modules.')

    def test_fail_bad_data_srt_file(self):
        link = reverse('upload_transcripts')
        filename = os.path.splitext(os.path.basename(self.bad_data_srt_file.name))[0]
        resp = self.client.post(link, {
            'locator': unicode(self.video_usage_key),
            'transcript-file': self.bad_data_srt_file,
            'video_list': json.dumps([{
                'type': 'html5',
                'video': filename,
                'mode': 'mp4',
            }])
        })
        self.assertEqual(resp.status_code, 400)
        self.assertEqual(json.loads(resp.content).get('status'), 'Something wrong with SubRip transcripts file during parsing.')

    def test_fail_bad_name_srt_file(self):
        link = reverse('upload_transcripts')
        filename = os.path.splitext(os.path.basename(self.bad_name_srt_file.name))[0]
        resp = self.client.post(link, {
            'locator': unicode(self.video_usage_key),
            'transcript-file': self.bad_name_srt_file,
            'video_list': json.dumps([{
                'type': 'html5',
                'video': filename,
                'mode': 'mp4',
            }])
        })
        self.assertEqual(resp.status_code, 400)
        self.assertEqual(json.loads(resp.content).get('status'), 'We support only SubRip (*.srt) transcripts format.')

    def test_undefined_file_extension(self):
        srt_file = tempfile.NamedTemporaryFile(suffix='')
        srt_file.write(textwrap.dedent("""
            1
            00:00:10,500 --> 00:00:13,000
            Elephant's Dream

            2
            00:00:15,000 --> 00:00:18,000
            At the left we can see...
        """))
        srt_file.seek(0)

        link = reverse('upload_transcripts')
        filename = os.path.splitext(os.path.basename(srt_file.name))[0]
        resp = self.client.post(link, {
            'locator': self.video_usage_key,
            'transcript-file': srt_file,
            'video_list': json.dumps([{
                'type': 'html5',
                'video': filename,
                'mode': 'mp4',
            }])
        })
        self.assertEqual(resp.status_code, 400)
        self.assertEqual(json.loads(resp.content).get('status'), 'Undefined file extension.')

    def test_subs_uploading_with_byte_order_mark(self):
        """
        Test uploading subs containing BOM(Byte Order Mark), e.g. U+FEFF
        """
        filedata = textwrap.dedent("""
            1
            00:00:10,500 --> 00:00:13,000
            Test ufeff characters

            2
            00:00:15,000 --> 00:00:18,000
            At the left we can see...
        """).encode('utf-8-sig')

        # Verify that ufeff character is in filedata.
        self.assertIn("ufeff", filedata)
        self.ufeff_srt_file.write(filedata)
        self.ufeff_srt_file.seek(0)

        link = reverse('upload_transcripts')
        filename = os.path.splitext(os.path.basename(self.ufeff_srt_file.name))[0]
        resp = self.client.post(link, {
            'locator': self.video_usage_key,
            'transcript-file': self.ufeff_srt_file,
            'video_list': json.dumps([{
                'type': 'html5',
                'video': filename,
                'mode': 'mp4',
            }])
        })
        self.assertEqual(resp.status_code, 200)

        content_location = StaticContent.compute_location(
            self.course.id, 'subs_{0}.srt.sjson'.format(filename))
        self.assertTrue(contentstore().find(content_location))

        subs_text = json.loads(contentstore().find(content_location).data).get('text')
        self.assertIn("Test ufeff characters", subs_text)

    def tearDown(self):
        super(TestUploadTranscripts, self).tearDown()

        self.good_srt_file.close()
        self.bad_data_srt_file.close()
        self.bad_name_srt_file.close()
        self.ufeff_srt_file.close()


class TestDownloadTranscripts(BaseTranscripts):
    """Tests for '/transcripts/download' url."""

    def save_subs_to_store(self, subs, subs_id):
        """Save transcripts into `StaticContent`."""
        filedata = json.dumps(subs, indent=2)
        mime_type = 'application/json'
        filename = 'subs_{0}.srt.sjson'.format(subs_id)

        content_location = StaticContent.compute_location(self.course.id, filename)
        content = StaticContent(content_location, filename, mime_type, filedata)
        contentstore().save(content)
        del_cached_content(content_location)
        return content_location

    def test_success_download_youtube(self):
        self.item.data = '<video youtube="1:JMD_ifUUfsU" />'
        modulestore().update_item(self.item, self.user.id)

        subs = {
            'start': [100, 200, 240],
            'end': [200, 240, 380],
            'text': [
                'subs #1',
                'subs #2',
                'subs #3'
            ]
        }
        self.save_subs_to_store(subs, 'JMD_ifUUfsU')

        link = reverse('download_transcripts')
        resp = self.client.get(link, {'locator': self.video_usage_key, 'subs_id': "JMD_ifUUfsU"})
        self.assertEqual(resp.status_code, 200)
        self.assertEqual(resp.content, """0\n00:00:00,100 --> 00:00:00,200\nsubs #1\n\n1\n00:00:00,200 --> 00:00:00,240\nsubs #2\n\n2\n00:00:00,240 --> 00:00:00,380\nsubs #3\n\n""")

    def test_success_download_nonyoutube(self):
        subs_id = str(uuid4())
        self.item.data = textwrap.dedent("""
            <video youtube="" sub="{}">
                <source src="http://www.quirksmode.org/html5/videos/big_buck_bunny.mp4"/>
                <source src="http://www.quirksmode.org/html5/videos/big_buck_bunny.webm"/>
                <source src="http://www.quirksmode.org/html5/videos/big_buck_bunny.ogv"/>
            </video>
        """.format(subs_id))
        modulestore().update_item(self.item, self.user.id)

        subs = {
            'start': [100, 200, 240],
            'end': [200, 240, 380],
            'text': [
                'subs #1',
                'subs #2',
                'subs #3'
            ]
        }
        self.save_subs_to_store(subs, subs_id)

        link = reverse('download_transcripts')
        resp = self.client.get(link, {'locator': self.video_usage_key, 'subs_id': subs_id})
        self.assertEqual(resp.status_code, 200)
        self.assertEqual(
            resp.content,
            '0\n00:00:00,100 --> 00:00:00,200\nsubs #1\n\n1\n00:00:00,200 --> '
            '00:00:00,240\nsubs #2\n\n2\n00:00:00,240 --> 00:00:00,380\nsubs #3\n\n'
        )
        transcripts_utils.remove_subs_from_store(subs_id, self.item)

    def test_fail_data_without_file(self):
        link = reverse('download_transcripts')
        resp = self.client.get(link, {'locator': ''})
        self.assertEqual(resp.status_code, 404)

        resp = self.client.get(link, {})
        self.assertEqual(resp.status_code, 404)

    def test_fail_data_with_bad_locator(self):
        # Test for raising `InvalidLocationError` exception.
        link = reverse('download_transcripts')
        resp = self.client.get(link, {'locator': 'BAD_LOCATOR'})
        self.assertEqual(resp.status_code, 404)

        # Test for raising `ItemNotFoundError` exception.
        link = reverse('download_transcripts')
        resp = self.client.get(link, {'locator': '{0}_{1}'.format(self.video_usage_key, 'BAD_LOCATOR')})
        self.assertEqual(resp.status_code, 404)

    def test_fail_for_non_video_module(self):
        # Video module: setup
        data = {
            'parent_locator': unicode(self.course.location),
            'category': 'videoalpha',
            'type': 'videoalpha'
        }
        resp = self.client.ajax_post('/xblock/', data)
        usage_key = self._get_usage_key(resp)
        subs_id = str(uuid4())
        item = modulestore().get_item(usage_key)
        item.data = textwrap.dedent("""
            <videoalpha youtube="" sub="{}">
                <source src="http://www.quirksmode.org/html5/videos/big_buck_bunny.mp4"/>
                <source src="http://www.quirksmode.org/html5/videos/big_buck_bunny.webm"/>
                <source src="http://www.quirksmode.org/html5/videos/big_buck_bunny.ogv"/>
            </videoalpha>
        """.format(subs_id))
        modulestore().update_item(item, self.user.id)

        subs = {
            'start': [100, 200, 240],
            'end': [200, 240, 380],
            'text': [
                'subs #1',
                'subs #2',
                'subs #3'
            ]
        }
        self.save_subs_to_store(subs, subs_id)

        link = reverse('download_transcripts')
        resp = self.client.get(link, {'locator': unicode(usage_key)})
        self.assertEqual(resp.status_code, 404)

    def test_fail_nonyoutube_subs_dont_exist(self):
        self.item.data = textwrap.dedent("""
            <video youtube="" sub="UNDEFINED">
                <source src="http://www.quirksmode.org/html5/videos/big_buck_bunny.mp4"/>
                <source src="http://www.quirksmode.org/html5/videos/big_buck_bunny.webm"/>
                <source src="http://www.quirksmode.org/html5/videos/big_buck_bunny.ogv"/>
            </video>
        """)
        modulestore().update_item(self.item, self.user.id)

        link = reverse('download_transcripts')
        resp = self.client.get(link, {'locator': self.video_usage_key})
        self.assertEqual(resp.status_code, 404)

    def test_empty_youtube_attr_and_sub_attr(self):
        self.item.data = textwrap.dedent("""
            <video youtube="">
                <source src="http://www.quirksmode.org/html5/videos/big_buck_bunny.mp4"/>
                <source src="http://www.quirksmode.org/html5/videos/big_buck_bunny.webm"/>
                <source src="http://www.quirksmode.org/html5/videos/big_buck_bunny.ogv"/>
            </video>
        """)
        modulestore().update_item(self.item, self.user.id)

        link = reverse('download_transcripts')
        resp = self.client.get(link, {'locator': self.video_usage_key})

        self.assertEqual(resp.status_code, 404)

    def test_fail_bad_sjson_subs(self):
        subs_id = str(uuid4())
        self.item.data = textwrap.dedent("""
            <video youtube="" sub="{}">
                <source src="http://www.quirksmode.org/html5/videos/big_buck_bunny.mp4"/>
                <source src="http://www.quirksmode.org/html5/videos/big_buck_bunny.webm"/>
                <source src="http://www.quirksmode.org/html5/videos/big_buck_bunny.ogv"/>
            </video>
        """.format(subs_id))
        modulestore().update_item(self.item, self.user.id)

        subs = {
            'start': [100, 200, 240],
            'end': [200, 240, 380],
            'text': [
                'subs #1'
            ]
        }
        self.save_subs_to_store(subs, 'JMD_ifUUfsU')

        link = reverse('download_transcripts')
        resp = self.client.get(link, {'locator': self.video_usage_key})

        self.assertEqual(resp.status_code, 404)


class TestCheckTranscripts(BaseTranscripts):
    """Tests for '/transcripts/check' url."""

    def save_subs_to_store(self, subs, subs_id):
        """Save transcripts into `StaticContent`."""
        filedata = json.dumps(subs, indent=2)
        mime_type = 'application/json'
        filename = 'subs_{0}.srt.sjson'.format(subs_id)

        content_location = StaticContent.compute_location(self.course.id, filename)
        content = StaticContent(content_location, filename, mime_type, filedata)
        contentstore().save(content)
        del_cached_content(content_location)
        return content_location

    def test_success_download_nonyoutube(self):
        subs_id = str(uuid4())
        self.item.data = textwrap.dedent("""
            <video youtube="" sub="{}">
                <source src="http://www.quirksmode.org/html5/videos/big_buck_bunny.mp4"/>
                <source src="http://www.quirksmode.org/html5/videos/big_buck_bunny.webm"/>
                <source src="http://www.quirksmode.org/html5/videos/big_buck_bunny.ogv"/>
            </video>
        """.format(subs_id))
        modulestore().update_item(self.item, self.user.id)

        subs = {
            'start': [100, 200, 240],
            'end': [200, 240, 380],
            'text': [
                'subs #1',
                'subs #2',
                'subs #3'
            ]
        }
        self.save_subs_to_store(subs, subs_id)

        data = {
            'locator': unicode(self.video_usage_key),
            'videos': [{
                'type': 'html5',
                'video': subs_id,
                'mode': 'mp4',
            }]
        }
        link = reverse('check_transcripts')
        resp = self.client.get(link, {'data': json.dumps(data)})
        self.assertEqual(resp.status_code, 200)
        self.assertDictEqual(
            json.loads(resp.content),
            {
                u'status': u'Success',
                u'subs': unicode(subs_id),
                u'youtube_local': False,
                u'is_youtube_mode': False,
                u'youtube_server': False,
                u'command': u'found',
                u'current_item_subs': unicode(subs_id),
                u'youtube_diff': True,
                u'html5_local': [unicode(subs_id)],
                u'html5_equal': False,
            }
        )

        transcripts_utils.remove_subs_from_store(subs_id, self.item)

    def test_check_youtube(self):
        self.item.data = '<video youtube="1:JMD_ifUUfsU" />'
        modulestore().update_item(self.item, self.user.id)

        subs = {
            'start': [100, 200, 240],
            'end': [200, 240, 380],
            'text': [
                'subs #1',
                'subs #2',
                'subs #3'
            ]
        }
        self.save_subs_to_store(subs, 'JMD_ifUUfsU')
        link = reverse('check_transcripts')
        data = {
            'locator': unicode(self.video_usage_key),
            'videos': [{
                'type': 'youtube',
                'video': 'JMD_ifUUfsU',
                'mode': 'youtube',
            }]
        }
        resp = self.client.get(link, {'data': json.dumps(data)})
        self.assertEqual(resp.status_code, 200)
        self.assertDictEqual(
            json.loads(resp.content),
            {
                u'status': u'Success',
                u'subs': u'JMD_ifUUfsU',
                u'youtube_local': True,
                u'is_youtube_mode': True,
                u'youtube_server': False,
                u'command': u'found',
                u'current_item_subs': None,
                u'youtube_diff': True,
                u'html5_local': [],
                u'html5_equal': False,
            }
        )

    @patch('xmodule.video_module.transcripts_utils.requests.get', side_effect=mock_requests_get)
    def test_check_youtube_with_transcript_name(self, mock_get):
        """
        Test that the transcripts are fetched correctly when the the transcript name is set
        """
        self.item.data = '<video youtube="good_id_2" />'
        modulestore().update_item(self.item, self.user.id)

        subs = {
            'start': [100, 200, 240],
            'end': [200, 240, 380],
            'text': [
                'subs #1',
                'subs #2',
                'subs #3'
            ]
        }
        self.save_subs_to_store(subs, 'good_id_2')
        link = reverse('check_transcripts')
        data = {
            'locator': unicode(self.video_usage_key),
            'videos': [{
                'type': 'youtube',
                'video': 'good_id_2',
                'mode': 'youtube',
            }]
        }
        resp = self.client.get(link, {'data': json.dumps(data)})

        mock_get.assert_any_call(
            'http://video.google.com/timedtext',
            params={'lang': 'en', 'v': 'good_id_2', 'name': 'Custom'}
        )

        self.assertEqual(resp.status_code, 200)

        self.assertDictEqual(
            json.loads(resp.content),
            {
                u'status': u'Success',
                u'subs': u'good_id_2',
                u'youtube_local': True,
                u'is_youtube_mode': True,
                u'youtube_server': True,
                u'command': u'replace',
                u'current_item_subs': None,
                u'youtube_diff': True,
                u'html5_local': [],
                u'html5_equal': False,
            }
        )

    def test_fail_data_without_id(self):
        link = reverse('check_transcripts')
        data = {
            'locator': '',
            'videos': [{
                'type': '',
                'video': '',
                'mode': '',
            }]
        }
        resp = self.client.get(link, {'data': json.dumps(data)})
        self.assertEqual(resp.status_code, 400)
        self.assertEqual(json.loads(resp.content).get('status'), "Can't find item by locator.")

    def test_fail_data_with_bad_locator(self):
        # Test for raising `InvalidLocationError` exception.
        link = reverse('check_transcripts')
        data = {
            'locator': '',
            'videos': [{
                'type': '',
                'video': '',
                'mode': '',
            }]
        }
        resp = self.client.get(link, {'data': json.dumps(data)})
        self.assertEqual(resp.status_code, 400)
        self.assertEqual(json.loads(resp.content).get('status'), "Can't find item by locator.")

        # Test for raising `ItemNotFoundError` exception.
        data = {
            'locator': '{0}_{1}'.format(self.video_usage_key, 'BAD_LOCATOR'),
            'videos': [{
                'type': '',
                'video': '',
                'mode': '',
            }]
        }
        resp = self.client.get(link, {'data': json.dumps(data)})
        self.assertEqual(resp.status_code, 400)
        self.assertEqual(json.loads(resp.content).get('status'), "Can't find item by locator.")

    def test_fail_for_non_video_module(self):
        # Not video module: setup
        data = {
            'parent_locator': unicode(self.course.location),
            'category': 'not_video',
            'type': 'not_video'
        }
        resp = self.client.ajax_post('/xblock/', data)
        usage_key = self._get_usage_key(resp)
        subs_id = str(uuid4())
        item = modulestore().get_item(usage_key)
        item.data = textwrap.dedent("""
            <not_video youtube="" sub="{}">
                <source src="http://www.quirksmode.org/html5/videos/big_buck_bunny.mp4"/>
                <source src="http://www.quirksmode.org/html5/videos/big_buck_bunny.webm"/>
                <source src="http://www.quirksmode.org/html5/videos/big_buck_bunny.ogv"/>
            </videoalpha>
        """.format(subs_id))
        modulestore().update_item(item, self.user.id)

        subs = {
            'start': [100, 200, 240],
            'end': [200, 240, 380],
            'text': [
                'subs #1',
                'subs #2',
                'subs #3'
            ]
        }
        self.save_subs_to_store(subs, subs_id)

        data = {
            'locator': unicode(usage_key),
            'videos': [{
                'type': '',
                'video': '',
                'mode': '',
            }]
        }
        link = reverse('check_transcripts')
        resp = self.client.get(link, {'data': json.dumps(data)})
        self.assertEqual(resp.status_code, 400)
        self.assertEqual(json.loads(resp.content).get('status'), 'Transcripts are supported only for "video" modules.')