# -*- coding: utf-8 -*-
#
# Copyright (C) 2014-2019 by the Free Software Foundation, Inc.
#
# This file is part of HyperKitty.
#
# HyperKitty is free software: you can redistribute it and/or modify it under
# the terms of the GNU General Public License as published by the Free
# Software Foundation, either version 3 of the License, or (at your option)
# any later version.
#
# HyperKitty is distributed in the hope that it will be useful, but WITHOUT
# ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
# FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
# more details.
#
# You should have received a copy of the GNU General Public License along with
# HyperKitty.  If not, see <http://www.gnu.org/licenses/>.
#
# Author: Aurelien Bompard <abompard@fedoraproject.org>
#

import datetime
import os
from email import message_from_file
from email.message import EmailMessage
from email.policy import default

from django.core.cache import cache
from django.db import DataError, IntegrityError
from django.utils import timezone

import mock

from hyperkitty.lib.incoming import DuplicateMessage, add_to_list
from hyperkitty.lib.utils import get_message_id_hash
from hyperkitty.models import Attachment, Email, MailingList, Thread
from hyperkitty.tests.utils import TestCase, get_test_file


class TestAddToList(TestCase):

    def test_basic(self):
        msg = EmailMessage()
        msg["From"] = "dummy@example.com"
        msg["Subject"] = "Fake Subject"
        msg["Message-ID"] = "<dummy>"
        msg["Date"] = "Fri, 02 Nov 2012 16:07:54"
        msg.set_payload("Fake Message")
        m_hash = add_to_list("example-list", msg)
        # Get the email by id
        try:
            m = Email.objects.get(message_id="dummy")
        except Email.DoesNotExist:
            self.fail("No email found by id")
        self.assertEqual(m.sender_id, "dummy@example.com")
        self.assertEqual(m.sender.address, "dummy@example.com")
        # Get the email by message_id_hash
        try:
            m = Email.objects.get(message_id_hash=m_hash)
        except Email.DoesNotExist:
            self.fail("No email found by hash")
        # The thread_id is created from the message_id_hash
        self.assertEqual(m.thread.thread_id, m_hash)

    def test_no_message_id(self):
        msg = EmailMessage()
        self.assertRaises(ValueError, add_to_list,
                          "example-list", msg)

    def test_no_date(self):
        msg = EmailMessage()
        msg["From"] = "dummy@example.com"
        msg["Message-ID"] = "<dummy>"
        msg.set_payload("Dummy message")
        now = timezone.now()
        try:
            add_to_list("example-list", msg)
        except IntegrityError as e:
            self.fail(e)
        self.assertEqual(Email.objects.count(), 1)
        stored_msg = Email.objects.all()[0]
        self.assertTrue(stored_msg.date >= now)

    def test_date_naive(self):
        msg = EmailMessage()
        msg["From"] = "dummy@example.com"
        msg["Message-ID"] = "<dummy>"
        msg["Date"] = "Fri, 02 Nov 2012 16:07:54"
        msg.set_payload("Dummy message")
        try:
            add_to_list("example-list", msg)
        except IntegrityError as e:
            self.fail(e)
        self.assertEqual(Email.objects.count(), 1)
        stored_msg = Email.objects.all()[0]
        expected = datetime.datetime(2012, 11, 2, 16, 7, 54,
                                     tzinfo=timezone.utc)
        self.assertEqual(stored_msg.date, expected)
        self.assertEqual(stored_msg.timezone, 0)

    def test_date_aware(self):
        msg = EmailMessage()
        msg["From"] = "dummy@example.com"
        msg["Message-ID"] = "<dummy>"
        msg["Date"] = "Fri, 02 Nov 2012 16:07:54 +0100"
        msg.set_payload("Dummy message")
        try:
            add_to_list("example-list", msg)
        except IntegrityError as e:
            self.fail(e)
        self.assertEqual(Email.objects.count(), 1)
        stored_msg = Email.objects.all()[0]
        expected = datetime.datetime(2012, 11, 2, 15, 7, 54,
                                     tzinfo=timezone.utc)
        self.assertEqual(stored_msg.date, expected)
        self.assertEqual(stored_msg.timezone, 60)

    def test_duplicate(self):
        msg = EmailMessage()
        msg["From"] = "dummy@example.com"
        msg["Message-ID"] = "<dummy>"
        msg.set_payload("Dummy message")
        add_to_list("example-list", msg)
        mlist = MailingList.objects.get(name="example-list")
        self.assertEqual(mlist.emails.count(), 1)
        self.assertTrue(mlist.emails.filter(message_id="dummy").exists())
        self.assertRaises(DuplicateMessage, add_to_list, "example-list", msg)
        self.assertEqual(mlist.emails.count(), 1)

    def test_non_ascii_email_address(self):
        """Non-ascii email addresses should raise a ValueError exception"""
        msg = EmailMessage(policy=default)
        msg["From"] = "dummy-non-ascii-\xc3\xa9@example.com"
        msg["Message-ID"] = "<dummy>"
        msg.set_payload("Dummy message")
        try:
            add_to_list("example-list", msg)
        except ValueError as e:
            self.assertEqual(e.__class__.__name__, "ValueError")
        else:
            self.fail("No ValueError was raised")
        self.assertEqual(
            MailingList.objects.get(name="example-list").emails.count(),
            0)

    def test_duplicate_nonascii(self):
        msg = EmailMessage()
        msg["From"] = "dummy-ascii@example.com"
        msg["Message-ID"] = "<dummy>"
        msg.set_payload("Dummy message")
        add_to_list("example-list", msg)
        mlist = MailingList.objects.get(name="example-list")
        self.assertEqual(mlist.emails.count(), 1)
        self.assertTrue(mlist.emails.filter(message_id="dummy").exists())
        msg.replace_header("From", "dummy-non-ascii\xc3\xa9@example.com")
        try:
            self.assertRaises(
                DuplicateMessage, add_to_list, "example-list", msg)
        except UnicodeDecodeError as e:
            self.fail("Died on a non-ascii header message: %s" % (e))
        self.assertEqual(mlist.emails.count(), 1)

    def test_attachment_insert_order(self):
        """Attachments must not be inserted in the DB before the email"""
        with open(get_test_file("attachment-1.txt")) as email_file:
            msg = message_from_file(email_file, EmailMessage, policy=default)
        try:
            add_to_list("example-list", msg)
        except IntegrityError as e:
            self.fail(e)
        self.assertEqual(Email.objects.count(), 1)
        self.assertEqual(Attachment.objects.count(), 1)

    def test_bytes_attachment(self):
        """Some attachments have content as bytes."""
        with open(get_test_file("attachment-2.txt")) as email_file:
            msg = message_from_file(email_file, EmailMessage, policy=default)
        try:
            add_to_list("example-list", msg)
        except IntegrityError as e:
            self.fail(e)
        self.assertEqual(Attachment.objects.count(), 1)

    def test_string_no_cset_attachment(self):
        """Some attachments have content as str with no specified encoding."""
        with open(get_test_file("attachment-3.txt")) as email_file:
            msg = message_from_file(email_file, EmailMessage, policy=default)
        try:
            add_to_list("example-list", msg)
        except IntegrityError as e:
            self.fail(e)
        self.assertEqual(Attachment.objects.count(), 1)

    def test_non_ascii_text_attachment_declared_as_ascii(self):
        # Some defective mail has a text attachment declared as ascii but
        # containing non-ascii. We should just replace the non-ascii character.
        with open(get_test_file("attachment-4.txt")) as email_file:
            msg = message_from_file(email_file, EmailMessage, policy=default)
        try:
            add_to_list("example-list", msg)
        except Exception as e:
            self.fail(e)
        self.assertEqual(Attachment.objects.count(), 1)
        self.assertEqual(Attachment.objects.all()[0].content,
                         b'All votes are reported in the form "*Y-N-A*" '
                         b'(*in favor-Y???opposed-N???abstentions-A*; e.g. '
                         b'"5-1-2" means "5 in favor, 1 opposed, and 2 '
                         b'abstentions").\n')

    def test_attachment_local_storage(self):
        # The HYPERKITTY_ATTACHMENT_FOLDER config allows usage of a local
        # folder for attachments.
        with open(get_test_file("attachment-1.txt")) as email_file:
            msg = message_from_file(email_file, EmailMessage, policy=default)
        attachment_folder = os.path.join(self.tmpdir, "attachments")
        with self.settings(HYPERKITTY_ATTACHMENT_FOLDER=attachment_folder):
            add_to_list("list@example.com", msg)
        self.assertEqual(Attachment.objects.count(), 1)
        attachment = Attachment.objects.all().first()
        self.assertIsNone(attachment.content, None)
        self.assertEqual(attachment.size, 49)
        filepath = os.path.join(
            attachment_folder, "example.com", "list", "E3", "YP", "52",
            "1", "2",
        )
        self.assertTrue(os.path.exists(filepath))
        self.assertEqual(os.path.getsize(filepath), 49)

    def test_attachment_local_storage_bad_list_name(self):
        # The HYPERKITTY_ATTACHMENT_FOLDER config allows usage of a local
        # folder for attachments. Verify that bad list names don't crash the
        # app.
        with open(get_test_file("attachment-1.txt")) as email_file:
            msg = message_from_file(email_file, EmailMessage, policy=default)
        attachment_folder = os.path.join(self.tmpdir, "attachments")
        with self.settings(HYPERKITTY_ATTACHMENT_FOLDER=attachment_folder):
            add_to_list("list.example.com", msg)
            add_to_list("list@local@example.com", msg)
        email1 = Email.objects.filter(
            mailinglist__name="list.example.com").first()
        email2 = Email.objects.filter(
            mailinglist__name="list@local@example.com").first()
        self.assertTrue(os.path.exists(os.path.join(
            attachment_folder, "list.example.com", "none", "E3", "YP", "52",
            str(email1.id), "2",
        )))
        self.assertTrue(os.path.exists(os.path.join(
            attachment_folder, "example.com", "list@local", "E3", "YP", "52",
            str(email2.id), "2",
        )))

    def test_thread_neighbors(self):
        # Create 3 threads
        msg_t1_1 = EmailMessage()
        msg_t1_1["From"] = "dummy@example.com"
        msg_t1_1["Message-ID"] = "<id1_1>"
        msg_t1_1.set_payload("Dummy message")
        add_to_list("example-list", msg_t1_1)
        msg_t2_1 = EmailMessage()
        msg_t2_1["From"] = "dummy@example.com"
        msg_t2_1["Message-ID"] = "<id2_1>"
        msg_t2_1.set_payload("Dummy message")
        add_to_list("example-list", msg_t2_1)
        msg_t3_1 = EmailMessage()
        msg_t3_1["From"] = "dummy@example.com"
        msg_t3_1["Message-ID"] = "<id3_1>"
        msg_t3_1.set_payload("Dummy message")
        add_to_list("example-list", msg_t3_1)

        # Check the neighbors
        def check_neighbors(thread, expected_prev, expected_next):
            thread_id = get_message_id_hash("<id%s_1>" % thread)
            thread = Thread.objects.get(thread_id=thread_id)
            prev_th = next_th = None
            # convert to something I can compare
            if thread.prev_thread:
                prev_th = thread.prev_thread.thread_id
            if thread.next_thread:
                next_th = thread.next_thread.thread_id
            expected_prev = expected_prev and \
                get_message_id_hash("<id%s_1>" % expected_prev)
            expected_next = expected_next and \
                get_message_id_hash("<id%s_1>" % expected_next)
            # compare
            self.assertEqual(prev_th, expected_prev)
            self.assertEqual(next_th, expected_next)
        # Order should be: 1, 2, 3
        check_neighbors(1, None, 2)
        check_neighbors(2, 1, 3)
        check_neighbors(3, 2, None)
        # now add a new message in thread 1, which becomes the most recently
        # active
        msg_t1_2 = EmailMessage()
        msg_t1_2["From"] = "dummy@example.com"
        msg_t1_2["Message-ID"] = "<id1_2>"
        msg_t1_2["In-Reply-To"] = "<id1_1>"
        msg_t1_2.set_payload("Dummy message")
        add_to_list("example-list", msg_t1_2)
        # Order should be: 2, 3, 1
        check_neighbors(2, None, 3)
        check_neighbors(3, 2, 1)
        check_neighbors(1, 3, None)

    def test_long_message_id(self):
        # Some message-ids are more than 255 chars long
        # Check with assert here because SQLite will not enforce the limit
        # (http://www.sqlite.org/faq.html#q9)
        msg = EmailMessage()
        msg["From"] = "dummy@example.com"
        msg["Message-ID"] = "X" * 260
        msg.set_payload("Dummy message")
        try:
            add_to_list("example-list", msg)
        except IntegrityError as e:
            self.fail(e)
        self.assertEqual(Email.objects.count(), 1)
        stored_msg = Email.objects.all()[0]
        self.assertTrue(
            len(stored_msg.message_id) <= 255,
            "Very long message-id headers are not truncated")

    def test_long_message_id_reply(self):
        # Some message-ids are more than 255 chars long, we'll truncate them
        # but check that references are preserved
        msg1 = EmailMessage()
        msg1["From"] = "dummy@example.com"
        msg1["Message-ID"] = "<" + ("X" * 260) + ">"
        msg1.set_payload("Dummy message")
        msg2 = EmailMessage()
        msg2["From"] = "dummy@example.com"
        msg2["Message-ID"] = "<Y>"
        msg2["References"] = "<" + ("X" * 260) + ">"
        msg2.set_payload("Dummy message")
        add_to_list("example-list", msg1)
        add_to_list("example-list", msg2)
        stored_msg1 = Email.objects.get(message_id="X" * 254)
        stored_msg2 = Email.objects.get(message_id="Y")
        self.assertEqual(stored_msg2.in_reply_to, "X" * 254)
        self.assertEqual(stored_msg2.parent_id, stored_msg1.id)
        self.assertEqual(stored_msg2.thread_order, 1)
        self.assertEqual(stored_msg2.thread_depth, 1)
        self.assertEqual(Thread.objects.count(), 1)
        thread = Thread.objects.all()[0]
        self.assertEqual(thread.emails.count(), 2)

    def test_top_participants(self):
        expected = [
            ("name3", "email3", 3),
            ("name2", "email2", 2),
            ("name1", "email1", 1),
            ]
        for name, email, count in expected:
            for num in range(count):
                msg = EmailMessage()
                msg["From"] = "%s <%s>" % (name, email)
                msg["Message-ID"] = "<%s_%s>" % (name, num)
                msg.set_payload("Dummy message")
                add_to_list("example-list", msg)
        mlist = MailingList.objects.get(name="example-list")
        result = [(p["name"], p["address"], p["count"]) for p in
                  mlist.top_posters]
        self.assertEqual(expected, result)

    def test_get_sender_name(self):
        msg = EmailMessage()
        msg["From"] = "Sender Name <dummy@example.com>"
        msg["Message-ID"] = "<dummy>"
        msg.set_payload("Dummy message")
        add_to_list("example-list", msg)
        self.assertEqual(Email.objects.count(), 1)
        stored_msg = Email.objects.all()[0]
        self.assertEqual(stored_msg.sender_name, "Sender Name")

    def test_no_sender_address(self):
        msg = EmailMessage()
        msg["From"] = "Sender Name <>"
        msg["Message-ID"] = "<dummy>"
        msg.set_payload("Dummy message")
        try:
            add_to_list("example-list", msg)
        except IntegrityError as e:
            self.fail(e)
        self.assertEqual(Email.objects.count(), 1)
        stored_msg = Email.objects.all()[0]
        self.assertEqual(stored_msg.sender_name, "Sender Name")
        self.assertEqual(stored_msg.sender.address, "sendername@example.com")

    def test_no_sender_name_or_address(self):
        msg = EmailMessage()
        msg["From"] = ""
        msg["Message-ID"] = "<dummy>"
        msg.set_payload("Dummy message")
        try:
            add_to_list("example-list", msg)
        except IntegrityError as e:
            self.fail(e)
        self.assertEqual(Email.objects.count(), 1)
        stored_msg = Email.objects.all()[0]
        self.assertEqual(stored_msg.sender_name, "")
        self.assertEqual(stored_msg.sender.address, "unknown@example.com")

    def test_get_sender_name_if_empty(self):
        msg = EmailMessage()
        msg["From"] = "dummy@example.com"
        msg["Message-ID"] = "<dummy>"
        msg.set_payload("Dummy message")
        add_to_list("example-list", msg)
        self.assertEqual(Email.objects.count(), 1)
        stored_msg = Email.objects.all()[0]
        self.assertEqual(stored_msg.sender_name, "dummy@example.com")

    def test_dont_update_sender_name(self):
        # This first part is equivalent to the test_get_sender_name test.
        msg = EmailMessage()
        msg["From"] = "Sender Name <dummy@example.com>"
        msg["Message-ID"] = "<dummy>"
        msg.set_payload("Dummy message")
        add_to_list("example-list", msg)
        self.assertEqual(Email.objects.count(), 1)
        stored_msg = Email.objects.all()[0]
        self.assertEqual(stored_msg.sender_name, "Sender Name")
        # Send a second message with a different sender name
        msg = EmailMessage()
        msg["From"] = "Another Name <dummy@example.com>"
        msg["Message-ID"] = "<dummy2>"
        msg.set_payload("Dummy message")
        add_to_list("example-list", msg)
        self.assertEqual(Email.objects.count(), 2)
        stored_msg_2 = Email.objects.get(message_id="dummy2")
        self.assertEqual(stored_msg_2.sender_name, "Another Name")
        # The first sender_name hasn't changed.
        self.assertEqual(stored_msg.sender_name, "Sender Name")

    def test_long_subject(self):
        msg = EmailMessage()
        msg["From"] = "dummy@example.com"
        msg["Message-ID"] = "<dummy>"
        msg["Subject"] = "x" * 600
        msg.set_payload("Dummy message")
        try:
            add_to_list("example-list", msg)
        except IntegrityError as e:
            self.fail(e)
        self.assertEqual(Email.objects.count(), 1)
        stored_msg = Email.objects.all()[0]
        self.assertEqual(len(stored_msg.subject), 512)

    def test_orphans(self):
        # When a reply is received before the original message, it must be
        # re-attached when the original message arrives
        orphan_msg = EmailMessage()
        orphan_msg["From"] = "person@example.com"
        orphan_msg["Message-ID"] = "<msg2>"
        orphan_msg["In-Reply-To"] = "<msg1>"
        orphan_msg.set_payload("Second message")
        add_to_list("example-list", orphan_msg)
        self.assertEqual(Email.objects.count(), 1)
        orphan = Email.objects.all()[0]
        self.assertIsNone(orphan.parent_id)
        parent_msg = EmailMessage()
        parent_msg["From"] = "person@example.com"
        parent_msg["Message-ID"] = "<msg1>"
        parent_msg.set_payload("First message")
        add_to_list("example-list", parent_msg)
        self.assertEqual(Email.objects.count(), 2)
        orphan = Email.objects.get(id=orphan.id)  # Refresh the instance
        parent = Email.objects.filter(message_id="msg1").first()
        self.assertEqual(orphan.parent_id, parent.id)

    def test_archived_date(self):
        msg = EmailMessage()
        msg["From"] = "dummy@example.com"
        msg["Subject"] = "Fake Subject"
        msg["Message-ID"] = "<dummy>"
        msg["Date"] = "Fri, 02 Nov 2012 16:07:54"
        msg.set_payload("Fake Message")
        msg.set_unixfrom("mail@example.com Mon Jul 21 11:59:48 2013")
        add_to_list("example-list", msg)
        self.assertEqual(Email.objects.count(), 1)
        stored_msg = Email.objects.all()[0]
        self.assertEqual(
            stored_msg.archived_date,
            datetime.datetime(2013, 7, 21, 11, 59, 48, tzinfo=timezone.utc))

    def test_archived_date_unparseable(self):
        msg = EmailMessage()
        msg["From"] = "dummy@example.com"
        msg["Subject"] = "Fake Subject"
        msg["Message-ID"] = "<dummy>"
        msg["Date"] = "Fri, 02 Nov 2012 16:07:54"
        msg.set_payload("Fake Message")
        msg.set_unixfrom("mail@example.com Something that cant be parsed")
        add_to_list("example-list", msg)
        self.assertEqual(Email.objects.count(), 1)
        stored_msg = Email.objects.all()[0]
        one_hour_ago = timezone.now() - datetime.timedelta(hours=1)
        self.assertTrue(stored_msg.archived_date > one_hour_ago)

    def test_rebuild_recent_threads_cache(self):
        # The recent threads cache must be rebuilt when a new message arrives.
        mlist = MailingList.objects.create(name="example-list")
        cache.set("MailingList:%s:recent_threads" % mlist.pk, [42])
        cache.set("MailingList:%s:recent_threads_count" % mlist.pk,
                  "test-value")
        msg = EmailMessage()
        msg["From"] = "dummy@example.com"
        msg["Subject"] = "Fake Subject"
        msg["Message-ID"] = "<dummy>"
        msg.set_payload("Fake Message")
        m_hash = add_to_list("example-list", msg)
        thread = Thread.objects.get(thread_id=m_hash)
        cached_value = cache.get("MailingList:%s:recent_threads" % mlist.pk)
        self.assertListEqual(list(cached_value), [thread.id])
        self.assertEqual(mlist.recent_threads[0].thread_id, m_hash)
        self.assertEqual(
            cache.get("MailingList:%s:recent_threads_count" % mlist.pk), 1)

    def test_existing_thread(self):
        msg = EmailMessage()
        msg["From"] = "dummy@example.com"
        msg["Subject"] = "Fake Subject"
        msg["Message-ID"] = "<dummy>"
        msg["Date"] = "Fri, 02 Nov 2012 16:07:54"
        msg.set_payload("Fake Message")
        # Create a thread with the same message_id
        mlist = MailingList.objects.create(name="example-list")
        thread = Thread.objects.create(
            mailinglist=mlist, thread_id=get_message_id_hash("dummy"))
        # Add the message
        m_hash = add_to_list("example-list", msg)
        self.assertEqual(m_hash, thread.thread_id)
        self.assertEqual(thread.emails.count(), 1)
        # Get the email
        try:
            email = Email.objects.get(message_id="dummy")
        except Email.DoesNotExist:
            self.fail("No email found by id")
        self.assertEqual(email.thread, thread)

    def test_data_error(self):
        # Verify that a DataError exception when calling save() is propertly
        # propagated.
        msg = EmailMessage()
        msg["From"] = "dummy@example.com"
        msg["Subject"] = "Fake Subject"
        msg["Message-ID"] = "<dummy>"
        msg["Date"] = "Fri, 02 Nov 2012 16:07:54"
        msg.set_payload("Fake Message")
        email = mock.Mock()
        email.save.side_effect = DataError("test error")
        with mock.patch("hyperkitty.lib.incoming.Email") as Email:
            Email.return_value = email
            filter_mock = mock.Mock()
            filter_mock.exists.return_value = False
            Email.objects.filter.return_value = filter_mock
            self.assertRaises(ValueError, add_to_list, "example-list", msg)
