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

import subprocess

from django.http import HttpResponse
from django.utils.timezone import now as timezone_now

from zerver.lib.test_helpers import (
    most_recent_message,
    most_recent_usermessage,
    POSTRequestMock)

from zerver.lib.test_classes import (
    ZulipTestCase,
)

from zerver.models import (
    get_display_recipient,
    get_realm,
    get_stream,
    get_client,
    Recipient,
    UserProfile,
    UserActivity,
    Realm
)

from zerver.lib.actions import (
    create_stream_if_needed,
    encode_email_address,
    do_create_user
)
from zerver.lib.email_mirror import (
    process_message, process_stream_message, ZulipEmailForwardError,
    create_missed_message_address,
    get_missed_message_token_from_address,
)

from zerver.lib.digest import gather_new_streams, handle_digest_email, enqueue_emails
from zerver.lib.send_email import FromAddress
from zerver.lib.notifications import (
    handle_missedmessage_emails,
)
from zerver.management.commands import email_mirror

from email.mime.text import MIMEText

import datetime
import time
import re
import ujson
import mock
import os
import sys
from io import StringIO
from django.conf import settings

from zerver.lib.str_utils import force_str
from typing import Any, Callable, Dict, Mapping, Union, Text

class TestEmailMirrorLibrary(ZulipTestCase):
    def test_get_missed_message_token(self) -> None:

        def get_token(address: Text) -> Text:
            with self.settings(EMAIL_GATEWAY_PATTERN="%s@example.com"):
                return get_missed_message_token_from_address(address)

        address = 'mm' + ('x' * 32) + '@example.com'
        token = get_token(address)
        self.assertEqual(token, 'x' * 32)

        # This next section was a bug at one point--we'd treat ordinary
        # user addresses that happened to begin with "mm" as being
        # the special mm+32chars tokens.
        address = 'mmathers@example.com'
        with self.assertRaises(ZulipEmailForwardError):
            get_token(address)

        # Now test the case where we our address does not match the
        # EMAIL_GATEWAY_PATTERN.
        # This used to crash in an ugly way; we want to throw a proper
        # exception.
        address = 'alice@not-the-domain-we-were-expecting.com'
        with self.assertRaises(ZulipEmailForwardError):
            get_token(address)

class TestStreamEmailMessagesSuccess(ZulipTestCase):
    def test_receive_stream_email_messages_success(self) -> None:

        # build dummy messages for stream
        # test valid incoming stream message is processed properly
        user_profile = self.example_user('hamlet')
        self.login(user_profile.email)
        self.subscribe(user_profile, "Denmark")
        stream = get_stream("Denmark", user_profile.realm)

        stream_to_address = encode_email_address(stream)

        incoming_valid_message = MIMEText('TestStreamEmailMessages Body')  # type: Any # https://github.com/python/typeshed/issues/275

        incoming_valid_message['Subject'] = 'TestStreamEmailMessages Subject'
        incoming_valid_message['From'] = self.example_email('hamlet')
        incoming_valid_message['To'] = stream_to_address
        incoming_valid_message['Reply-to'] = self.example_email('othello')

        process_message(incoming_valid_message)

        # Hamlet is subscribed to this stream so should see the email message from Othello.
        message = most_recent_message(user_profile)

        self.assertEqual(message.content, "TestStreamEmailMessages Body")
        self.assertEqual(get_display_recipient(message.recipient), stream.name)
        self.assertEqual(message.topic_name(), incoming_valid_message['Subject'])

class TestStreamEmailMessagesEmptyBody(ZulipTestCase):
    def test_receive_stream_email_messages_empty_body(self) -> None:

        # build dummy messages for stream
        # test message with empty body is not sent
        user_profile = self.example_user('hamlet')
        self.login(user_profile.email)
        self.subscribe(user_profile, "Denmark")
        stream = get_stream("Denmark", user_profile.realm)

        stream_to_address = encode_email_address(stream)
        headers = {}
        headers['Reply-To'] = self.example_email('othello')

        # empty body
        incoming_valid_message = MIMEText('')  # type: Any # https://github.com/python/typeshed/issues/275

        incoming_valid_message['Subject'] = 'TestStreamEmailMessages Subject'
        incoming_valid_message['From'] = self.example_email('hamlet')
        incoming_valid_message['To'] = stream_to_address
        incoming_valid_message['Reply-to'] = self.example_email('othello')

        exception_message = ""
        debug_info = {}  # type: Dict[str, Any]

        # process_message eats the exception & logs an error which can't be parsed here
        # so calling process_stream_message directly
        try:
            process_stream_message(incoming_valid_message['To'],
                                   incoming_valid_message['Subject'],
                                   incoming_valid_message,
                                   debug_info)
        except ZulipEmailForwardError as e:
            # empty body throws exception
            exception_message = str(e)
        self.assertEqual(exception_message, "Unable to find plaintext or HTML message body")

class TestMissedPersonalMessageEmailMessages(ZulipTestCase):
    def test_receive_missed_personal_message_email_messages(self) -> None:

        # build dummy messages for missed messages email reply
        # have Hamlet send Othello a PM. Othello will reply via email
        # Hamlet will receive the message.
        email = self.example_email('hamlet')
        self.login(email)
        result = self.client_post("/json/messages", {"type": "private",
                                                     "content": "test_receive_missed_message_email_messages",
                                                     "client": "test suite",
                                                     "to": self.example_email('othello')})
        self.assert_json_success(result)

        user_profile = self.example_user('othello')
        usermessage = most_recent_usermessage(user_profile)

        # we don't want to send actual emails but we do need to create and store the
        # token for looking up who did reply.
        mm_address = create_missed_message_address(user_profile, usermessage.message)

        incoming_valid_message = MIMEText('TestMissedMessageEmailMessages Body')  # type: Any # https://github.com/python/typeshed/issues/275

        incoming_valid_message['Subject'] = 'TestMissedMessageEmailMessages Subject'
        incoming_valid_message['From'] = self.example_email('othello')
        incoming_valid_message['To'] = mm_address
        incoming_valid_message['Reply-to'] = self.example_email('othello')

        process_message(incoming_valid_message)

        # self.login(self.example_email("hamlet"))
        # confirm that Hamlet got the message
        user_profile = self.example_user('hamlet')
        message = most_recent_message(user_profile)

        self.assertEqual(message.content, "TestMissedMessageEmailMessages Body")
        self.assertEqual(message.sender, self.example_user('othello'))
        self.assertEqual(message.recipient.id, user_profile.id)
        self.assertEqual(message.recipient.type, Recipient.PERSONAL)

class TestMissedHuddleMessageEmailMessages(ZulipTestCase):
    def test_receive_missed_huddle_message_email_messages(self) -> None:

        # build dummy messages for missed messages email reply
        # have Othello send Iago and Cordelia a PM. Cordelia will reply via email
        # Iago and Othello will receive the message.
        email = self.example_email('othello')
        self.login(email)
        result = self.client_post("/json/messages", {"type": "private",
                                                     "content": "test_receive_missed_message_email_messages",
                                                     "client": "test suite",
                                                     "to": ujson.dumps([self.example_email('cordelia'),
                                                                        self.example_email('iago')])})
        self.assert_json_success(result)

        user_profile = self.example_user('cordelia')
        usermessage = most_recent_usermessage(user_profile)

        # we don't want to send actual emails but we do need to create and store the
        # token for looking up who did reply.
        mm_address = create_missed_message_address(user_profile, usermessage.message)

        incoming_valid_message = MIMEText('TestMissedHuddleMessageEmailMessages Body')  # type: Any # https://github.com/python/typeshed/issues/275

        incoming_valid_message['Subject'] = 'TestMissedHuddleMessageEmailMessages Subject'
        incoming_valid_message['From'] = self.example_email('cordelia')
        incoming_valid_message['To'] = mm_address
        incoming_valid_message['Reply-to'] = self.example_email('cordelia')

        process_message(incoming_valid_message)

        # Confirm Iago received the message.
        user_profile = self.example_user('iago')
        message = most_recent_message(user_profile)

        self.assertEqual(message.content, "TestMissedHuddleMessageEmailMessages Body")
        self.assertEqual(message.sender, self.example_user('cordelia'))
        self.assertEqual(message.recipient.type, Recipient.HUDDLE)

        # Confirm Othello received the message.
        user_profile = self.example_user('othello')
        message = most_recent_message(user_profile)

        self.assertEqual(message.content, "TestMissedHuddleMessageEmailMessages Body")
        self.assertEqual(message.sender, self.example_user('cordelia'))
        self.assertEqual(message.recipient.type, Recipient.HUDDLE)

class TestEmptyGatewaySetting(ZulipTestCase):
    def test_missed_message(self) -> None:
        email = self.example_email('othello')
        self.login(email)
        result = self.client_post("/json/messages", {"type": "private",
                                                     "content": "test_receive_missed_message_email_messages",
                                                     "client": "test suite",
                                                     "to": ujson.dumps([self.example_email('cordelia'),
                                                                        self.example_email('iago')])})
        self.assert_json_success(result)

        user_profile = self.example_user('cordelia')
        usermessage = most_recent_usermessage(user_profile)
        with self.settings(EMAIL_GATEWAY_PATTERN=''):
            mm_address = create_missed_message_address(user_profile, usermessage.message)
            self.assertEqual(mm_address, FromAddress.NOREPLY)

    def test_encode_email_addr(self) -> None:
        stream = get_stream("Denmark", get_realm("zulip"))

        with self.settings(EMAIL_GATEWAY_PATTERN=''):
            test_address = encode_email_address(stream)
            self.assertEqual(test_address, '')

class TestDigestEmailMessages(ZulipTestCase):
    @mock.patch('zerver.lib.digest.enough_traffic')
    @mock.patch('zerver.lib.digest.send_future_email')
    def test_receive_digest_email_messages(self, mock_send_future_email: mock.MagicMock,
                                           mock_enough_traffic: mock.MagicMock) -> None:

        # build dummy messages for missed messages email reply
        # have Hamlet send Othello a PM. Othello will reply via email
        # Hamlet will receive the message.
        email = self.example_email('hamlet')
        self.login(email)
        result = self.client_post("/json/messages", {"type": "private",
                                                     "content": "test_receive_missed_message_email_messages",
                                                     "client": "test suite",
                                                     "to": self.example_email('othello')})
        self.assert_json_success(result)

        user_profile = self.example_user('othello')
        cutoff = time.mktime(datetime.datetime(year=2016, month=1, day=1).timetuple())

        handle_digest_email(user_profile.id, cutoff)
        self.assertEqual(mock_send_future_email.call_count, 1)
        self.assertEqual(mock_send_future_email.call_args[1]['to_user_id'], user_profile.id)

    @mock.patch('zerver.lib.digest.queue_digest_recipient')
    @mock.patch('zerver.lib.digest.timezone_now')
    def test_inactive_users_queued_for_digest(self, mock_django_timezone: mock.MagicMock,
                                              mock_queue_digest_recipient: mock.MagicMock) -> None:
        cutoff = timezone_now()
        # Test Tuesday
        mock_django_timezone.return_value = datetime.datetime(year=2016, month=1, day=5)
        all_user_profiles = UserProfile.objects.filter(
            is_active=True, is_bot=False, enable_digest_emails=True)
        # Check that all users without an a UserActivity entry are considered
        # inactive users and get enqueued.
        enqueue_emails(cutoff)
        self.assertEqual(mock_queue_digest_recipient.call_count, all_user_profiles.count())
        mock_queue_digest_recipient.reset_mock()
        for realm in Realm.objects.filter(deactivated=False, show_digest_email=True):
            user_profiles = all_user_profiles.filter(realm=realm)
            for user_profile in user_profiles:
                UserActivity.objects.create(
                    last_visit=cutoff - datetime.timedelta(days=1),
                    user_profile=user_profile,
                    count=0,
                    client=get_client('test_client'))
        # Check that inactive users are enqueued
        enqueue_emails(cutoff)
        self.assertEqual(mock_queue_digest_recipient.call_count, all_user_profiles.count())

    @mock.patch('zerver.lib.digest.enough_traffic', return_value=True)
    @mock.patch('zerver.lib.digest.timezone_now')
    def test_active_users_not_enqueued(self, mock_django_timezone: mock.MagicMock,
                                       mock_enough_traffic: mock.MagicMock) -> None:
        cutoff = timezone_now()
        # A Tuesday
        mock_django_timezone.return_value = datetime.datetime(year=2016, month=1, day=5)
        realms = Realm.objects.filter(deactivated=False, show_digest_email=True)
        for realm in realms:
            user_profiles = UserProfile.objects.filter(realm=realm)
            for counter, user_profile in enumerate(user_profiles, 1):
                UserActivity.objects.create(
                    last_visit=cutoff + datetime.timedelta(days=1),
                    user_profile=user_profile,
                    count=0,
                    client=get_client('test_client'))
        # Check that an active user is not enqueued
        with mock.patch('zerver.lib.digest.queue_digest_recipient') as mock_queue_digest_recipient:
            enqueue_emails(cutoff)
            self.assertEqual(mock_queue_digest_recipient.call_count, 0)

    @mock.patch('zerver.lib.digest.queue_digest_recipient')
    @mock.patch('zerver.lib.digest.timezone_now')
    def test_only_enqueue_on_valid_day(self, mock_django_timezone: mock.MagicMock,
                                       mock_queue_digest_recipient: mock.MagicMock) -> None:
        # Not a Tuesday
        mock_django_timezone.return_value = datetime.datetime(year=2016, month=1, day=6)

        # Check that digests are not sent on days other than Tuesday.
        cutoff = timezone_now()
        enqueue_emails(cutoff)
        self.assertEqual(mock_queue_digest_recipient.call_count, 0)

    @mock.patch('zerver.lib.digest.queue_digest_recipient')
    @mock.patch('zerver.lib.digest.timezone_now')
    def test_no_email_digest_for_bots(self, mock_django_timezone: mock.MagicMock,
                                      mock_queue_digest_recipient: mock.MagicMock) -> None:
        cutoff = timezone_now()
        # A Tuesday
        mock_django_timezone.return_value = datetime.datetime(year=2016, month=1, day=5)
        bot = do_create_user('some_bot@example.com', 'password', get_realm('zulip'), 'some_bot', '',
                             bot_type=UserProfile.DEFAULT_BOT)
        UserActivity.objects.create(
            last_visit=cutoff - datetime.timedelta(days=1),
            user_profile=bot,
            count=0,
            client=get_client('test_client'))

        # Check that bots are not sent emails
        enqueue_emails(cutoff)
        for arg in mock_queue_digest_recipient.call_args_list:
            user = arg[0][0]
            self.assertNotEqual(user.id, bot.id)

    @mock.patch('zerver.lib.digest.timezone_now')
    def test_new_stream_link(self, mock_django_timezone: mock.MagicMock) -> None:
        cutoff = datetime.datetime(year=2017, month=11, day=1)
        mock_django_timezone.return_value = datetime.datetime(year=2017, month=11, day=5)
        cordelia = self.example_user('cordelia')
        create_stream_if_needed(cordelia.realm, 'New stream')
        new_stream = gather_new_streams(cordelia, cutoff)[1]
        expected_html = "<a href='http://zulip.testserver/#narrow/stream/New.20stream'>New stream</a>"
        self.assertIn(expected_html, new_stream['html'])

class TestReplyExtraction(ZulipTestCase):
    def test_reply_is_extracted_from_plain(self) -> None:

        # build dummy messages for stream
        # test valid incoming stream message is processed properly
        email = self.example_email('hamlet')
        self.login(email)
        user_profile = self.example_user('hamlet')
        self.subscribe(user_profile, "Denmark")
        stream = get_stream("Denmark", user_profile.realm)

        stream_to_address = encode_email_address(stream)
        text = """Reply

        -----Original Message-----

        Quote"""

        incoming_valid_message = MIMEText(text)  # type: Any # https://github.com/python/typeshed/issues/275

        incoming_valid_message['Subject'] = 'TestStreamEmailMessages Subject'
        incoming_valid_message['From'] = self.example_email('hamlet')
        incoming_valid_message['To'] = stream_to_address
        incoming_valid_message['Reply-to'] = self.example_email('othello')

        process_message(incoming_valid_message)

        # Hamlet is subscribed to this stream so should see the email message from Othello.
        message = most_recent_message(user_profile)

        self.assertEqual(message.content, "Reply")

    def test_reply_is_extracted_from_html(self) -> None:

        # build dummy messages for stream
        # test valid incoming stream message is processed properly
        email = self.example_email('hamlet')
        self.login(email)
        user_profile = self.example_user('hamlet')
        self.subscribe(user_profile, "Denmark")
        stream = get_stream("Denmark", user_profile.realm)

        stream_to_address = encode_email_address(stream)
        html = """
        <html>
            <body>
                <p>Reply</p>
                <blockquote>

                    <div>
                        On 11-Apr-2011, at 6:54 PM, Bob &lt;bob@example.com&gt; wrote:
                    </div>

                    <div>
                        Quote
                    </div>

                </blockquote>
            </body>
        </html>
        """

        incoming_valid_message = MIMEText(html, 'html')  # type: Any # https://github.com/python/typeshed/issues/275

        incoming_valid_message['Subject'] = 'TestStreamEmailMessages Subject'
        incoming_valid_message['From'] = self.example_email('hamlet')
        incoming_valid_message['To'] = stream_to_address
        incoming_valid_message['Reply-to'] = self.example_email('othello')

        process_message(incoming_valid_message)

        # Hamlet is subscribed to this stream so should see the email message from Othello.
        message = most_recent_message(user_profile)

        self.assertEqual(message.content, 'Reply')

MAILS_DIR = os.path.join(os.path.dirname(os.path.dirname(os.path.abspath(__file__))), "fixtures", "email")


class TestScriptMTA(ZulipTestCase):

    def test_success(self) -> None:
        script = os.path.join(os.path.dirname(__file__),
                              '../../scripts/lib/email-mirror-postfix')

        sender = self.example_email('hamlet')
        stream = get_stream("Denmark", get_realm("zulip"))
        stream_to_address = encode_email_address(stream)

        template_path = os.path.join(MAILS_DIR, "simple.txt")
        with open(template_path) as template_file:
            mail_template = template_file.read()
        mail = mail_template.format(stream_to_address=stream_to_address, sender=sender)
        read_pipe, write_pipe = os.pipe()
        os.write(write_pipe, mail.encode())
        os.close(write_pipe)
        subprocess.check_call(
            [script, '-r', force_str(stream_to_address), '-s', settings.SHARED_SECRET, '-t'],
            stdin=read_pipe)

    def test_error_no_recipient(self) -> None:
        script = os.path.join(os.path.dirname(__file__),
                              '../../scripts/lib/email-mirror-postfix')

        sender = self.example_email('hamlet')
        stream = get_stream("Denmark", get_realm("zulip"))
        stream_to_address = encode_email_address(stream)
        template_path = os.path.join(MAILS_DIR, "simple.txt")
        with open(template_path) as template_file:
            mail_template = template_file.read()
        mail = mail_template.format(stream_to_address=stream_to_address, sender=sender)
        read_pipe, write_pipe = os.pipe()
        os.write(write_pipe, mail.encode())
        os.close(write_pipe)
        success_call = True
        try:
            subprocess.check_output([script, '-s', settings.SHARED_SECRET, '-t'],
                                    stdin=read_pipe)
        except subprocess.CalledProcessError as e:
            self.assertEqual(
                e.output,
                b'5.1.1 Bad destination mailbox address: No missed message email address.\n'
            )
            self.assertEqual(e.returncode, 67)
            success_call = False
        self.assertFalse(success_call)


class TestEmailMirrorTornadoView(ZulipTestCase):

    def send_private_message(self) -> Text:
        email = self.example_email('othello')
        self.login(email)
        result = self.client_post(
            "/json/messages",
            {
                "type": "private",
                "content": "test_receive_missed_message_email_messages",
                "client": "test suite",
                "to": ujson.dumps([self.example_email('cordelia'), self.example_email('iago')])
            })
        self.assert_json_success(result)

        user_profile = self.example_user('cordelia')
        user_message = most_recent_usermessage(user_profile)
        return create_missed_message_address(user_profile, user_message.message)

    @mock.patch('zerver.lib.email_mirror.queue_json_publish')
    def send_offline_message(self, to_address: str, sender: str,
                             mock_queue_json_publish: mock.Mock) -> HttpResponse:
        template_path = os.path.join(MAILS_DIR, "simple.txt")
        with open(template_path) as template_file:
            mail_template = template_file.read()
        mail = mail_template.format(stream_to_address=to_address, sender=sender)

        def check_queue_json_publish(queue_name: str,
                                     event: Union[Mapping[str, Any], str],
                                     processor: Callable[[Any], None]=None) -> None:
            self.assertEqual(queue_name, "email_mirror")
            self.assertEqual(event, {"rcpt_to": to_address, "message": mail})

        mock_queue_json_publish.side_effect = check_queue_json_publish
        request_data = {
            "recipient": to_address,
            "msg_text": mail
        }
        post_data = dict(
            data=ujson.dumps(request_data),
            secret=settings.SHARED_SECRET
        )
        return self.client_post('/email_mirror_message', post_data)

    def test_success_stream(self) -> None:
        stream = get_stream("Denmark", get_realm("zulip"))
        stream_to_address = encode_email_address(stream)
        result = self.send_offline_message(stream_to_address, self.example_email('hamlet'))
        self.assert_json_success(result)

    def test_error_to_stream_with_wrong_address(self) -> None:
        stream = get_stream("Denmark", get_realm("zulip"))
        stream_to_address = encode_email_address(stream)
        stream_to_address = stream_to_address.replace("Denmark", "Wrong_stream")

        result = self.send_offline_message(stream_to_address, self.example_email('hamlet'))
        self.assert_json_error(
            result,
            "5.1.1 Bad destination mailbox address: "
            "Please use the address specified in your Streams page.")

    def test_success_to_private(self) -> None:
        mm_address = self.send_private_message()
        result = self.send_offline_message(mm_address, self.example_email('cordelia'))
        self.assert_json_success(result)

    def test_using_mm_address_twice(self) -> None:
        mm_address = self.send_private_message()
        self.send_offline_message(mm_address, self.example_email('cordelia'))
        result = self.send_offline_message(mm_address, self.example_email('cordelia'))
        self.assert_json_error(
            result,
            "5.1.1 Bad destination mailbox address: Bad or expired missed message address.")

    def test_wrong_missed_email_private_message(self) -> None:
        self.send_private_message()
        mm_address = 'mm' + ('x' * 32) + '@testserver'
        result = self.send_offline_message(mm_address, self.example_email('cordelia'))
        self.assert_json_error(
            result,
            "5.1.1 Bad destination mailbox address: Bad or expired missed message address.")