# -*- coding: utf-8 -*-
from __future__ import absolute_import
from django.conf import settings
from django.test import TestCase, override_settings
from unittest import skip

from zerver.lib.avatar import avatar_url
from zerver.lib.bugdown import url_filename
from zerver.lib.test_classes import ZulipTestCase
from zerver.lib.test_helpers import avatar_disk_path, get_test_image_file
from zerver.lib.test_runner import slow
from zerver.lib.upload import sanitize_name, S3UploadBackend, \
    upload_message_image, delete_message_image, LocalUploadBackend
import zerver.lib.upload
from zerver.models import Attachment, Recipient, get_user_profile_by_email, \
    get_old_unclaimed_attachments, Message, UserProfile
from zerver.lib.actions import do_delete_old_unclaimed_attachments

import ujson
from six.moves import urllib
from PIL import Image

from boto.s3.connection import S3Connection
from boto.s3.key import Key
from six.moves import StringIO as _StringIO
import mock
import os
import io
import shutil
import re
import datetime
import requests
import base64
from datetime import timedelta
from django.utils import timezone

from moto import mock_s3

from typing import Any, Callable, TypeVar, Text

def destroy_uploads():
    # type: () -> None
    if os.path.exists(settings.LOCAL_UPLOADS_DIR):
        shutil.rmtree(settings.LOCAL_UPLOADS_DIR)

class StringIO(_StringIO):
    name = '' # https://github.com/python/typeshed/issues/598

class FileUploadTest(ZulipTestCase):

    def test_rest_endpoint(self):
        # type: () -> None
        """
        Tests the /api/v1/user_uploads api endpoint. Here a single file is uploaded
        and downloaded using a username and api_key
        """
        fp = StringIO("zulip!")
        fp.name = "zulip.txt"

        # Upload file via API
        auth_headers = self.api_auth('hamlet@zulip.com')
        result = self.client_post('/api/v1/user_uploads', {'file': fp}, **auth_headers)
        json = ujson.loads(result.content)
        self.assertIn("uri", json)
        uri = json["uri"]
        base = '/user_uploads/'
        self.assertEqual(base, uri[:len(base)])

        # Download file via API
        self.client_post('/accounts/logout/')
        response = self.client_get(uri, **auth_headers)
        data = b"".join(response.streaming_content)
        self.assertEqual(b"zulip!", data)

        # Files uploaded through the API should be accesible via the web client
        self.login("hamlet@zulip.com")
        self.assert_url_serves_contents_of_file(uri, b"zulip!")

    def test_file_too_big_failure(self):
        # type: () -> None
        """
        Attempting to upload big files should fail.
        """
        self.login("hamlet@zulip.com")
        fp = StringIO("bah!")
        fp.name = "a.txt"

        # Use MAX_FILE_UPLOAD_SIZE of 0, because the next increment
        # would be 1MB.
        with self.settings(MAX_FILE_UPLOAD_SIZE=0):
            result = self.client_post("/json/upload_file", {'f1': fp})
        self.assert_json_error(result, 'Uploaded file is larger than the allowed limit of 0 MB')

    def test_multiple_upload_failure(self):
        # type: () -> None
        """
        Attempting to upload two files should fail.
        """
        self.login("hamlet@zulip.com")
        fp = StringIO("bah!")
        fp.name = "a.txt"
        fp2 = StringIO("pshaw!")
        fp2.name = "b.txt"

        result = self.client_post("/json/upload_file", {'f1': fp, 'f2': fp2})
        self.assert_json_error(result, "You may only upload one file at a time")

    def test_no_file_upload_failure(self):
        # type: () -> None
        """
        Calling this endpoint with no files should fail.
        """
        self.login("hamlet@zulip.com")

        result = self.client_post("/json/upload_file")
        self.assert_json_error(result, "You must specify a file to upload")

    def test_download_non_existent_file(self):
        # type: () -> None
        self.login("hamlet@zulip.com")
        response = self.client_get('/user_uploads/unk/nonexistent_file')
        self.assertEqual(response.status_code, 404)
        self.assertIn('File not found', str(response.content))

    def test_serve_s3_error_handling(self):
        # type: () -> None
        self.login("hamlet@zulip.com")
        use_s3 = lambda: self.settings(LOCAL_UPLOADS_DIR=None)
        getting_realm_id = lambda realm_id: mock.patch(
            'zerver.views.upload.get_realm_for_filename',
            return_value=realm_id
        )

        # nonexistent_file
        with use_s3(), getting_realm_id(None):
            response = self.client_get('/user_uploads/unk/nonexistent_file')
        self.assertEqual(response.status_code, 404)
        self.assertIn('File not found', str(response.content))

        # invalid realm of 999999 (for non-zulip.com)
        user = get_user_profile_by_email('hamlet@zulip.com')
        user.realm.domain = 'example.com'
        user.realm.save()

        with use_s3(), getting_realm_id(999999):
            response = self.client_get('/user_uploads/unk/whatever')
        self.assertEqual(response.status_code, 403)

    # This test will go through the code path for uploading files onto LOCAL storage
    # when zulip is in DEVELOPMENT mode.
    def test_file_upload_authed(self):
        # type: () -> None
        """
        A call to /json/upload_file should return a uri and actually create an
        entry in the database. This entry will be marked unclaimed till a message
        refers it.
        """
        self.login("hamlet@zulip.com")
        fp = StringIO("zulip!")
        fp.name = "zulip.txt"

        result = self.client_post("/json/upload_file", {'file': fp})
        self.assert_json_success(result)
        json = ujson.loads(result.content)
        self.assertIn("uri", json)
        uri = json["uri"]
        base = '/user_uploads/'
        self.assertEqual(base, uri[:len(base)])

        # In the future, local file requests will follow the same style as S3
        # requests; they will be first authenthicated and redirected
        self.assert_url_serves_contents_of_file(uri, b"zulip!")

        # check if DB has attachment marked as unclaimed
        entry = Attachment.objects.get(file_name='zulip.txt')
        self.assertEqual(entry.is_claimed(), False)

        self.subscribe_to_stream("hamlet@zulip.com", "Denmark")
        body = "First message ...[zulip.txt](http://localhost:9991" + uri + ")"
        self.send_message("hamlet@zulip.com", "Denmark", Recipient.STREAM, body, "test")
        self.assertIn('title="zulip.txt"', self.get_last_message().rendered_content)

    def test_delete_old_unclaimed_attachments(self):
        # type: () -> None

        # Upload some files and make them older than a weeek
        self.login("hamlet@zulip.com")
        d1 = StringIO("zulip!")
        d1.name = "dummy_1.txt"
        result = self.client_post("/json/upload_file", {'file': d1})
        json = ujson.loads(result.content)
        uri = json["uri"]
        d1_path_id = re.sub('/user_uploads/', '', uri)

        d2 = StringIO("zulip!")
        d2.name = "dummy_2.txt"
        result = self.client_post("/json/upload_file", {'file': d2})
        json = ujson.loads(result.content)
        uri = json["uri"]
        d2_path_id = re.sub('/user_uploads/', '', uri)

        two_week_ago = timezone.now() - datetime.timedelta(weeks=2)
        d1_attachment = Attachment.objects.get(path_id = d1_path_id)
        d1_attachment.create_time = two_week_ago
        d1_attachment.save()
        self.assertEqual(str(d1_attachment), u'<Attachment: dummy_1.txt>')
        d2_attachment = Attachment.objects.get(path_id = d2_path_id)
        d2_attachment.create_time = two_week_ago
        d2_attachment.save()

        # Send message refering only dummy_1
        self.subscribe_to_stream("hamlet@zulip.com", "Denmark")
        body = "Some files here ...[zulip.txt](http://localhost:9991/user_uploads/" + d1_path_id + ")"
        self.send_message("hamlet@zulip.com", "Denmark", Recipient.STREAM, body, "test")

        # dummy_2 should not exist in database or the uploads folder
        do_delete_old_unclaimed_attachments(2)
        self.assertTrue(not Attachment.objects.filter(path_id = d2_path_id).exists())
        self.assertTrue(not delete_message_image(d2_path_id))

    def test_multiple_claim_attachments(self):
        # type: () -> None
        """
        This test tries to claim the same attachment twice. The messages field in
        the Attachment model should have both the messages in its entry.
        """
        self.login("hamlet@zulip.com")
        d1 = StringIO("zulip!")
        d1.name = "dummy_1.txt"
        result = self.client_post("/json/upload_file", {'file': d1})
        json = ujson.loads(result.content)
        uri = json["uri"]
        d1_path_id = re.sub('/user_uploads/', '', uri)

        self.subscribe_to_stream("hamlet@zulip.com", "Denmark")
        body = "First message ...[zulip.txt](http://localhost:9991/user_uploads/" + d1_path_id + ")"
        self.send_message("hamlet@zulip.com", "Denmark", Recipient.STREAM, body, "test")
        body = "Second message ...[zulip.txt](http://localhost:9991/user_uploads/" + d1_path_id + ")"
        self.send_message("hamlet@zulip.com", "Denmark", Recipient.STREAM, body, "test")

        self.assertEqual(Attachment.objects.get(path_id=d1_path_id).messages.count(), 2)

    def test_check_attachment_reference_update(self):
        # type: () -> None
        f1 = StringIO("file1")
        f1.name = "file1.txt"
        f2 = StringIO("file2")
        f2.name = "file2.txt"
        f3 = StringIO("file3")
        f3.name = "file3.txt"

        self.login("hamlet@zulip.com")
        result = self.client_post("/json/upload_file", {'file': f1})
        json = ujson.loads(result.content)
        uri = json["uri"]
        f1_path_id = re.sub('/user_uploads/', '', uri)

        result = self.client_post("/json/upload_file", {'file': f2})
        json = ujson.loads(result.content)
        uri = json["uri"]
        f2_path_id = re.sub('/user_uploads/', '', uri)

        self.subscribe_to_stream("hamlet@zulip.com", "test")
        body = ("[f1.txt](http://localhost:9991/user_uploads/" + f1_path_id + ")"
                "[f2.txt](http://localhost:9991/user_uploads/" + f2_path_id + ")")
        msg_id = self.send_message("hamlet@zulip.com", "test", Recipient.STREAM, body, "test")

        result = self.client_post("/json/upload_file", {'file': f3})
        json = ujson.loads(result.content)
        uri = json["uri"]
        f3_path_id = re.sub('/user_uploads/', '', uri)

        new_body = ("[f3.txt](http://localhost:9991/user_uploads/" + f3_path_id + ")"
                    "[f2.txt](http://localhost:9991/user_uploads/" + f2_path_id + ")")
        result = self.client_patch("/json/messages/" + str(msg_id), {
            'message_id': msg_id,
            'content': new_body
        })
        self.assert_json_success(result)

        message = Message.objects.get(id=msg_id)
        f1_attachment = Attachment.objects.get(path_id=f1_path_id)
        f2_attachment = Attachment.objects.get(path_id=f2_path_id)
        f3_attachment = Attachment.objects.get(path_id=f3_path_id)

        self.assertTrue(message not in f1_attachment.messages.all())
        self.assertTrue(message in f2_attachment.messages.all())
        self.assertTrue(message in f3_attachment.messages.all())

        # Delete all the attachments from the message
        new_body = "(deleted)"
        result = self.client_patch("/json/messages/" + str(msg_id), {
            'message_id': msg_id,
            'content': new_body
        })
        self.assert_json_success(result)

        message = Message.objects.get(id=msg_id)
        f1_attachment = Attachment.objects.get(path_id=f1_path_id)
        f2_attachment = Attachment.objects.get(path_id=f2_path_id)
        f3_attachment = Attachment.objects.get(path_id=f3_path_id)
        self.assertTrue(message not in f1_attachment.messages.all())
        self.assertTrue(message not in f2_attachment.messages.all())
        self.assertTrue(message not in f3_attachment.messages.all())

    def test_file_name(self):
        # type: () -> None
        """
        Unicode filenames should be processed correctly.
        """
        self.login("hamlet@zulip.com")
        for expected in ["Здравейте.txt", "test"]:
            fp = StringIO("bah!")
            fp.name = urllib.parse.quote(expected)

            result = self.client_post("/json/upload_file", {'f1': fp})
            content = ujson.loads(result.content)
            assert sanitize_name(expected) in content['uri']

    def tearDown(self):
        # type: () -> None
        destroy_uploads()

class AvatarTest(ZulipTestCase):

    def test_multiple_upload_failure(self):
        # type: () -> None
        """
        Attempting to upload two files should fail.
        """
        self.login("hamlet@zulip.com")
        with get_test_image_file('img.png') as fp1, \
                get_test_image_file('img.png') as fp2:
            result = self.client_put_multipart("/json/users/me/avatar", {'f1': fp1, 'f2': fp2})
        self.assert_json_error(result, "You must upload exactly one avatar.")

    def test_no_file_upload_failure(self):
        # type: () -> None
        """
        Calling this endpoint with no files should fail.
        """
        self.login("hamlet@zulip.com")

        result = self.client_put_multipart("/json/users/me/avatar")
        self.assert_json_error(result, "You must upload exactly one avatar.")

    correct_files = [
        ('img.png', 'png_resized.png'),
        ('img.jpg', None), # jpeg resizing is platform-dependent
        ('img.gif', 'gif_resized.png'),
        ('img.tif', 'tif_resized.png')
    ]
    corrupt_files = ['text.txt', 'corrupt.png', 'corrupt.gif']

    def test_get_gravatar_avatar(self):
        # type: () -> None
        self.login("hamlet@zulip.com")
        cordelia = get_user_profile_by_email('cordelia@zulip.com')

        cordelia.avatar_source = UserProfile.AVATAR_FROM_GRAVATAR
        cordelia.save()
        with self.settings(ENABLE_GRAVATAR=True):
            response = self.client_get("/avatar/cordelia@zulip.com?foo=bar")
            redirect_url = response['Location']
            self.assertEqual(redirect_url, avatar_url(cordelia) + '&foo=bar')

        with self.settings(ENABLE_GRAVATAR=False):
            response = self.client_get("/avatar/cordelia@zulip.com?foo=bar")
            redirect_url = response['Location']
            self.assertTrue(redirect_url.endswith(avatar_url(cordelia) + '&foo=bar'))

    def test_get_user_avatar(self):
        # type: () -> None
        self.login("hamlet@zulip.com")
        cordelia = get_user_profile_by_email('cordelia@zulip.com')

        cordelia.avatar_source = UserProfile.AVATAR_FROM_USER
        cordelia.save()
        response = self.client_get("/avatar/cordelia@zulip.com?foo=bar")
        redirect_url = response['Location']
        self.assertTrue(redirect_url.endswith(avatar_url(cordelia) + '&foo=bar'))

    def test_non_valid_user_avatar(self):
        # type: () -> None

        # It's debatable whether we should generate avatars for non-users,
        # but this test just validates the current code's behavior.
        self.login("hamlet@zulip.com")

        response = self.client_get("/avatar/nonexistent_user@zulip.com?foo=bar")
        redirect_url = response['Location']
        actual_url = 'https://secure.gravatar.com/avatar/444258b521f152129eb0c162996e572d?d=identicon&foo=bar'
        self.assertEqual(redirect_url, actual_url)

    def test_valid_avatars(self):
        # type: () -> None
        """
        A PUT request to /json/users/me/avatar with a valid file should return a url and actually create an avatar.
        """
        for fname, rfname in self.correct_files:
            # TODO: use self.subTest once we're exclusively on python 3 by uncommenting the line below.
            # with self.subTest(fname=fname):
            self.login("hamlet@zulip.com")
            with get_test_image_file(fname) as fp:
                result = self.client_put_multipart("/json/users/me/avatar", {'file': fp})

            self.assert_json_success(result)
            json = ujson.loads(result.content)
            self.assertIn("avatar_url", json)
            url = json["avatar_url"]
            base = '/user_avatars/'
            self.assertEqual(base, url[:len(base)])

            if rfname is not None:
                response = self.client_get(url)
                data = b"".join(response.streaming_content)
                self.assertEqual(Image.open(io.BytesIO(data)).size, (100, 100))

            # Verify that the medium-size avatar was created
            user_profile = get_user_profile_by_email('hamlet@zulip.com')
            medium_avatar_disk_path = avatar_disk_path(user_profile, medium=True)
            self.assertTrue(os.path.exists(medium_avatar_disk_path))

            # Confirm that ensure_medium_avatar_url works to recreate
            # medium size avatars from the original if needed
            os.remove(medium_avatar_disk_path)
            self.assertFalse(os.path.exists(medium_avatar_disk_path))
            zerver.lib.upload.upload_backend.ensure_medium_avatar_image(user_profile.email)
            self.assertTrue(os.path.exists(medium_avatar_disk_path))

    def test_invalid_avatars(self):
        # type: () -> None
        """
        A PUT request to /json/users/me/avatar with an invalid file should fail.
        """
        for fname in self.corrupt_files:
            # with self.subTest(fname=fname):
            self.login("hamlet@zulip.com")
            with get_test_image_file(fname) as fp:
                result = self.client_put_multipart("/json/users/me/avatar", {'file': fp})

            self.assert_json_error(result, "Could not decode avatar image; did you upload an image file?")

    def test_delete_avatar(self):
        # type: () -> None
        """
        A DELETE request to /json/users/me/avatar should delete the user avatar and return gravatar URL
        """
        self.login("hamlet@zulip.com")
        hamlet = get_user_profile_by_email("hamlet@zulip.com")
        hamlet.avatar_source = UserProfile.AVATAR_FROM_USER
        hamlet.save()

        result = self.client_delete("/json/users/me/avatar")
        user_profile = get_user_profile_by_email('hamlet@zulip.com')

        self.assert_json_success(result)
        json = ujson.loads(result.content)
        self.assertIn("avatar_url", json)
        self.assertEqual(json["avatar_url"], avatar_url(user_profile))

        self.assertEqual(user_profile.avatar_source, UserProfile.AVATAR_FROM_GRAVATAR)

    def tearDown(self):
        # type: () -> None
        destroy_uploads()

class LocalStorageTest(ZulipTestCase):

    def test_file_upload_local(self):
        # type: () -> None
        sender_email = "hamlet@zulip.com"
        user_profile = get_user_profile_by_email(sender_email)
        uri = upload_message_image(u'dummy.txt', u'text/plain', b'zulip!', user_profile)

        base = '/user_uploads/'
        self.assertEqual(base, uri[:len(base)])
        path_id = re.sub('/user_uploads/', '', uri)
        file_path = os.path.join(settings.LOCAL_UPLOADS_DIR, 'files', path_id)
        self.assertTrue(os.path.isfile(file_path))

    def test_delete_message_image_local(self):
        # type: () -> None
        self.login("hamlet@zulip.com")
        fp = StringIO("zulip!")
        fp.name = "zulip.txt"
        result = self.client_post("/json/upload_file", {'file': fp})

        json = ujson.loads(result.content)
        uri = json["uri"]
        path_id = re.sub('/user_uploads/', '', uri)
        self.assertTrue(delete_message_image(path_id))

    def tearDown(self):
        # type: () -> None
        destroy_uploads()

FuncT = TypeVar('FuncT', bound=Callable[..., None])

def use_s3_backend(method):
    # type: (FuncT) -> FuncT
    @mock_s3
    @override_settings(LOCAL_UPLOADS_DIR=None)
    def new_method(*args, **kwargs):
        # type: (*Any, **Any) -> Any
        zerver.lib.upload.upload_backend = S3UploadBackend()
        try:
            return method(*args, **kwargs)
        finally:
            zerver.lib.upload.upload_backend = LocalUploadBackend()
    return new_method

class S3Test(ZulipTestCase):

    @use_s3_backend
    def test_file_upload_s3(self):
        # type: () -> None
        conn = S3Connection(settings.S3_KEY, settings.S3_SECRET_KEY)
        bucket = conn.create_bucket(settings.S3_AUTH_UPLOADS_BUCKET)

        sender_email = "hamlet@zulip.com"
        user_profile = get_user_profile_by_email(sender_email)
        uri = upload_message_image(u'dummy.txt', u'text/plain', b'zulip!', user_profile)

        base = '/user_uploads/'
        self.assertEqual(base, uri[:len(base)])
        path_id = re.sub('/user_uploads/', '', uri)
        self.assertEqual(b"zulip!", bucket.get_key(path_id).get_contents_as_string())

        self.subscribe_to_stream("hamlet@zulip.com", "Denmark")
        body = "First message ...[zulip.txt](http://localhost:9991" + uri + ")"
        self.send_message("hamlet@zulip.com", "Denmark", Recipient.STREAM, body, "test")
        self.assertIn('title="dummy.txt"', self.get_last_message().rendered_content)

    @use_s3_backend
    def test_message_image_delete_s3(self):
        # type: () -> None
        conn = S3Connection(settings.S3_KEY, settings.S3_SECRET_KEY)
        conn.create_bucket(settings.S3_AUTH_UPLOADS_BUCKET)

        sender_email = "hamlet@zulip.com"
        user_profile = get_user_profile_by_email(sender_email)
        uri = upload_message_image(u'dummy.txt', u'text/plain', b'zulip!', user_profile)

        path_id = re.sub('/user_uploads/', '', uri)
        self.assertTrue(delete_message_image(path_id))

    @use_s3_backend
    def test_file_upload_authed(self):
        # type: () -> None
        """
        A call to /json/upload_file should return a uri and actually create an object.
        """
        conn = S3Connection(settings.S3_KEY, settings.S3_SECRET_KEY)
        conn.create_bucket(settings.S3_AUTH_UPLOADS_BUCKET)

        self.login("hamlet@zulip.com")
        fp = StringIO("zulip!")
        fp.name = "zulip.txt"

        result = self.client_post("/json/upload_file", {'file': fp})
        self.assert_json_success(result)
        json = ujson.loads(result.content)
        self.assertIn("uri", json)
        uri = json["uri"]
        base = '/user_uploads/'
        self.assertEqual(base, uri[:len(base)])

        response = self.client_get(uri)
        redirect_url = response['Location']

        self.assertEqual(b"zulip!", urllib.request.urlopen(redirect_url).read().strip()) # type: ignore # six.moves.urllib.request.urlopen is not defined in typeshed

        self.subscribe_to_stream("hamlet@zulip.com", "Denmark")
        body = "First message ...[zulip.txt](http://localhost:9991" + uri + ")"
        self.send_message("hamlet@zulip.com", "Denmark", Recipient.STREAM, body, "test")
        self.assertIn('title="zulip.txt"', self.get_last_message().rendered_content)

class UploadTitleTests(TestCase):
    def test_upload_titles(self):
        # type: () -> None
        self.assertEqual(url_filename("http://localhost:9991/user_uploads/1/LUeQZUG5jxkagzVzp1Ox_amr/dummy.txt"), "dummy.txt")
        self.assertEqual(url_filename("http://localhost:9991/user_uploads/1/94/SzGYe0RFT-tEcOhQ6n-ZblFZ/zulip.txt"), "zulip.txt")
        self.assertEqual(url_filename("https://zulip.com/user_uploads/4142/LUeQZUG5jxkagzVzp1Ox_amr/pasted_image.png"), "pasted_image.png")
        self.assertEqual(url_filename("https://zulipchat.com/integrations"), "https://zulipchat.com/integrations")
        self.assertEqual(url_filename("https://example.com"), "https://example.com")

class SanitizeNameTests(TestCase):
    def test_file_name(self):
        # type: () -> None
        self.assertEqual(sanitize_name(u'test.txt'), u'test.txt')
        self.assertEqual(sanitize_name(u'.hidden'), u'.hidden')
        self.assertEqual(sanitize_name(u'.hidden.txt'), u'.hidden.txt')
        self.assertEqual(sanitize_name(u'tarball.tar.gz'), u'tarball.tar.gz')
        self.assertEqual(sanitize_name(u'.hidden_tarball.tar.gz'), u'.hidden_tarball.tar.gz')
        self.assertEqual(sanitize_name(u'Testing{}*&*#().ta&&%$##&&r.gz'), u'Testing.tar.gz')
        self.assertEqual(sanitize_name(u'*testingfile?*.txt'), u'testingfile.txt')
        self.assertEqual(sanitize_name(u'snowman☃.txt'), u'snowman.txt')
        self.assertEqual(sanitize_name(u'테스트.txt'), u'테스트.txt')
        self.assertEqual(sanitize_name(u'~/."\`\?*"u0`000ssh/test.t**{}ar.gz'), u'.u0000sshtest.tar.gz')