from __future__ import absolute_import

import mimetypes
from os import path

from django.conf import settings
from django.conf.urls.static import static
from django.test import TestCase
from django.http import HttpResponseNotModified
from django.views.static import STREAM_CHUNK_SIZE

from .. import urls
from ..urls import media_dir


class StaticTests(TestCase):
    """Tests django views in django/views/static.py"""

    def setUp(self):
        self.prefix = 'site_media'
        self.old_debug = settings.DEBUG
        settings.DEBUG = True

    def tearDown(self):
        settings.DEBUG = self.old_debug

    def test_serve(self):
        "The static view can serve static media"
        media_files = ['file.txt', 'file.txt.gz']
        for filename in media_files:
            response = self.client.get('/views/%s/%s' % (self.prefix, filename))
            file_path = path.join(media_dir, filename)
            content = response.content
            self.assertEqual(open(file_path).read(), content)
            self.assertEqual(len(content), int(response['Content-Length']))
            self.assertEqual(mimetypes.guess_type(file_path)[1], response.get('Content-Encoding', None))

    def test_chunked(self):
        "The static view should stream files in chunks to avoid large memory usage"
        response = self.client.get('/views/%s/%s' % (self.prefix, 'long-line.txt'))
        first_chunk = iter(response).next()
        self.assertEqual(len(first_chunk), STREAM_CHUNK_SIZE)
        second_chunk = response.next()
        self.assertEqual(len(second_chunk), 1451)

    def test_unknown_mime_type(self):
        response = self.client.get('/views/%s/file.unknown' % self.prefix)
        self.assertEqual('application/octet-stream', response['Content-Type'])

    def test_copes_with_empty_path_component(self):
        file_name = 'file.txt'
        response = self.client.get('/views/%s//%s' % (self.prefix, file_name))
        file = open(path.join(media_dir, file_name))
        self.assertEqual(file.read(), response.content)

    def test_is_modified_since(self):
        file_name = 'file.txt'
        response = self.client.get('/views/%s/%s' % (self.prefix, file_name),
            HTTP_IF_MODIFIED_SINCE='Thu, 1 Jan 1970 00:00:00 GMT')
        file = open(path.join(media_dir, file_name))
        self.assertEqual(file.read(), response.content)

    def test_not_modified_since(self):
        file_name = 'file.txt'
        response = self.client.get(
            '/views/%s/%s' % (self.prefix, file_name),
            HTTP_IF_MODIFIED_SINCE='Mon, 18 Jan 2038 05:14:07 GMT'
            # This is 24h before max Unix time. Remember to fix Django and
            # update this test well before 2038 :)
            )
        self.assertTrue(isinstance(response, HttpResponseNotModified))

    def test_invalid_if_modified_since(self):
        """Handle bogus If-Modified-Since values gracefully

        Assume that a file is modified since an invalid timestamp as per RFC
        2616, section 14.25.
        """
        file_name = 'file.txt'
        invalid_date = 'Mon, 28 May 999999999999 28:25:26 GMT'
        response = self.client.get('/views/%s/%s' % (self.prefix, file_name),
                                   HTTP_IF_MODIFIED_SINCE=invalid_date)
        file = open(path.join(media_dir, file_name))
        content = response.content
        self.assertEqual(file.read(), content)
        self.assertEqual(len(content), int(response['Content-Length']))

    def test_invalid_if_modified_since2(self):
        """Handle even more bogus If-Modified-Since values gracefully

        Assume that a file is modified since an invalid timestamp as per RFC
        2616, section 14.25.
        """
        file_name = 'file.txt'
        invalid_date = ': 1291108438, Wed, 20 Oct 2010 14:05:00 GMT'
        response = self.client.get('/views/%s/%s' % (self.prefix, file_name),
                                   HTTP_IF_MODIFIED_SINCE=invalid_date)
        file = open(path.join(media_dir, file_name))
        content = response.content
        self.assertEqual(file.read(), content)
        self.assertEqual(len(content), int(response['Content-Length']))


class StaticHelperTest(StaticTests):
    """
    Test case to make sure the static URL pattern helper works as expected
    """
    def setUp(self):
        super(StaticHelperTest, self).setUp()
        self.prefix = 'media'
        self._old_views_urlpatterns = urls.urlpatterns[:]
        urls.urlpatterns += static('/media/', document_root=media_dir)

    def tearDown(self):
        super(StaticHelperTest, self).tearDown()
        urls.urlpatterns = self._old_views_urlpatterns