from datetime import timedelta
from email.headerregistry import Address

import time_machine
from django.conf import settings
from django.core import mail
from django.utils.html import escape
from django.utils.timezone import now

from confirmation.models import (
    Confirmation,
    confirmation_url,
    create_confirmation_link,
    generate_key,
)
from zerver.actions.create_user import do_reactivate_user
from zerver.actions.realm_settings import do_deactivate_realm, do_set_realm_property
from zerver.actions.user_settings import do_change_user_setting, do_start_email_change_process
from zerver.actions.users import do_deactivate_user
from zerver.lib.test_classes import ZulipTestCase
from zerver.models import EmailChangeStatus, UserProfile
from zerver.models.realms import get_realm
from zerver.models.users import get_user, get_user_by_delivery_email, get_user_profile_by_id


class EmailChangeTestCase(ZulipTestCase):
    def generate_email_change_link(self, new_email: str) -> str:
        data = {"email": new_email}
        url = "/json/settings"
        self.assert_length(mail.outbox, 0)
        result = self.client_patch(url, data)
        self.assert_length(mail.outbox, 1)
        self.assert_json_success(result)
        email_message = mail.outbox[0]
        self.assertEqual(
            email_message.subject,
            "Verify your new email address for zulip.testserver",
        )
        body = email_message.body
        self.assertIn("We received a request to change the email", body)

        mail.outbox.pop()

        activation_url = [s for s in body.split("\n") if s][2]
        return activation_url

    def test_confirm_email_change_with_non_existent_key(self) -> None:
        self.login("hamlet")
        key = generate_key()
        url = confirmation_url(key, None, Confirmation.EMAIL_CHANGE)
        response = self.client_get(url)
        self.assertEqual(response.status_code, 404)
        self.assert_in_response(
            "Whoops. We couldn't find your confirmation link in the system.", response
        )

    def test_confirm_email_change_with_invalid_key(self) -> None:
        self.login("hamlet")
        key = "invalid_key"
        url = confirmation_url(key, None, Confirmation.EMAIL_CHANGE)
        response = self.client_get(url)
        self.assertEqual(response.status_code, 404)
        self.assert_in_response("Whoops. The confirmation link is malformed.", response)

    def test_confirm_email_change_when_time_exceeded(self) -> None:
        user_profile = self.example_user("hamlet")
        old_email = user_profile.email
        new_email = "hamlet-new@zulip.com"
        self.login("hamlet")
        obj = EmailChangeStatus.objects.create(
            new_email=new_email,
            old_email=old_email,
            user_profile=user_profile,
            realm=user_profile.realm,
        )
        date_sent = now() - timedelta(days=2)
        with time_machine.travel(date_sent, tick=False):
            url = create_confirmation_link(obj, Confirmation.EMAIL_CHANGE)

        response = self.client_get(url)
        self.assertEqual(response.status_code, 404)
        self.assert_in_response("The confirmation link has expired or been deactivated.", response)

    def test_confirm_email_change(self) -> None:
        user_profile = self.example_user("hamlet")

        old_email = user_profile.delivery_email
        new_email = '"<li>hamlet-new<li>"@zulip.com'
        new_email_address = Address(addr_spec=new_email)
        new_realm = get_realm("zulip")
        self.login("hamlet")
        obj = EmailChangeStatus.objects.create(
            new_email=new_email,
            old_email=old_email,
            user_profile=user_profile,
            realm=user_profile.realm,
        )
        url = create_confirmation_link(obj, Confirmation.EMAIL_CHANGE)
        response = self.client_get(url)

        self.assertEqual(response.status_code, 200)
        self.assert_in_success_response(
            [
                "This confirms that the email address for your Zulip",
                f'<a href="mailto:{escape(new_email)}">{escape(new_email_address.username)}@<wbr>{escape(new_email_address.domain)}</wbr></a>',
            ],
            response,
        )
        user_profile = get_user_by_delivery_email(new_email, new_realm)
        self.assertTrue(bool(user_profile))
        obj.refresh_from_db()
        self.assertEqual(obj.status, 1)

    def test_change_email_link_cant_be_reused(self) -> None:
        new_email = "hamlet-new@zulip.com"
        user_profile = self.example_user("hamlet")
        self.login_user(user_profile)

        activation_url = self.generate_email_change_link(new_email)
        response = self.client_get(activation_url)
        self.assertEqual(response.status_code, 200)

        user_profile.refresh_from_db()
        self.assertEqual(user_profile.delivery_email, new_email)

        response = self.client_get(activation_url)
        self.assertEqual(response.status_code, 404)

    def test_change_email_revokes(self) -> None:
        user_profile = self.example_user("hamlet")
        self.login_user(user_profile)
        old_email = user_profile.delivery_email

        first_email = "hamlet-newer@zulip.com"
        first_url = self.generate_email_change_link(first_email)
        second_email = "hamlet-newest@zulip.com"
        second_url = self.generate_email_change_link(second_email)
        response = self.client_get(first_url)
        self.assertEqual(response.status_code, 404)
        user_profile.refresh_from_db()
        self.assertEqual(user_profile.delivery_email, old_email)

        response = self.client_get(second_url)
        self.assertEqual(response.status_code, 200)
        user_profile.refresh_from_db()
        self.assertEqual(user_profile.delivery_email, second_email)

    def test_change_email_deactivated_user_realm(self) -> None:
        new_email = "hamlet-new@zulip.com"
        user_profile = self.example_user("hamlet")
        self.login_user(user_profile)

        activation_url = self.generate_email_change_link(new_email)

        do_deactivate_user(user_profile, acting_user=None)
        response = self.client_get(activation_url)
        self.assertEqual(response.status_code, 401)

        do_reactivate_user(user_profile, acting_user=None)
        self.login_user(user_profile)
        activation_url = self.generate_email_change_link(new_email)

        do_deactivate_realm(
            user_profile.realm,
            acting_user=None,
            deactivation_reason="owner_request",
            email_owners=False,
        )

        response = self.client_get(activation_url)
        self.assertEqual(response.status_code, 302)
        self.assertTrue(response["Location"].endswith("/accounts/deactivated/"))

    def test_start_email_change_process(self) -> None:
        user_profile = self.example_user("hamlet")
        do_start_email_change_process(user_profile, "hamlet-new@zulip.com")
        self.assertEqual(EmailChangeStatus.objects.count(), 1)

    def test_end_to_end_flow(self) -> None:
        data = {"email": "hamlet-new@zulip.com"}
        self.login("hamlet")
        url = "/json/settings"
        self.assert_length(mail.outbox, 0)
        result = self.client_patch(url, data)
        self.assert_json_success(result)
        self.assert_length(mail.outbox, 1)
        email_message = mail.outbox[0]
        self.assertEqual(
            email_message.subject,
            "Verify your new email address for zulip.testserver",
        )
        body = email_message.body
        self.assertIn("We received a request to change the email", body)
        self.assertEqual(self.email_envelope_from(email_message), settings.NOREPLY_EMAIL_ADDRESS)
        self.assertRegex(
            self.email_display_from(email_message),
            rf"^testserver account security <{self.TOKENIZED_NOREPLY_REGEX}>\Z",
        )

        self.assertEqual(email_message.extra_headers["List-Id"], "Zulip Dev <zulip.testserver>")

        activation_url = [s for s in body.split("\n") if s][2]
        response = self.client_get(activation_url)

        self.assert_in_success_response(["This confirms that the email address"], response)

        # Now confirm trying to change your email back doesn't throw an immediate error
        result = self.client_patch(url, {"email": "hamlet@zulip.com"})
        self.assert_json_success(result)

    def test_unauthorized_email_change(self) -> None:
        data = {"email": "hamlet-new@zulip.com"}
        user_profile = self.example_user("hamlet")
        self.login_user(user_profile)
        do_set_realm_property(
            user_profile.realm,
            "email_changes_disabled",
            True,
            acting_user=None,
        )
        url = "/json/settings"
        result = self.client_patch(url, data)
        self.assert_length(mail.outbox, 0)
        self.assertEqual(result.status_code, 400)
        self.assert_in_response("Email address changes are disabled in this organization.", result)
        # Realm admins can change their email address even setting is disabled.
        data = {"email": "iago-new@zulip.com"}
        self.login("iago")
        url = "/json/settings"
        result = self.client_patch(url, data)
        self.assert_json_success(result)

    def test_email_change_already_taken(self) -> None:
        data = {"email": "cordelia@zulip.com"}
        user_profile = self.example_user("hamlet")
        self.login_user(user_profile)

        url = "/json/settings"
        result = self.client_patch(url, data)
        self.assert_length(mail.outbox, 0)
        self.assertEqual(result.status_code, 400)
        self.assert_in_response("Already has an account", result)

    def test_email_change_already_taken_later(self) -> None:
        conflict_email = "conflict@zulip.com"
        hamlet = self.example_user("hamlet")
        cordelia = self.example_user("cordelia")

        self.login_user(hamlet)
        hamlet_url = self.generate_email_change_link(conflict_email)
        self.logout()

        self.login_user(cordelia)
        cordelia_url = self.generate_email_change_link(conflict_email)
        response = self.client_get(cordelia_url)
        self.assertEqual(response.status_code, 200)
        cordelia.refresh_from_db()
        self.assertEqual(cordelia.delivery_email, conflict_email)

        self.logout()
        self.login_user(hamlet)
        response = self.client_get(hamlet_url)
        self.assertEqual(response.status_code, 400)
        self.assert_in_response("Already has an account", response)

    def test_change_email_to_disposable_email(self) -> None:
        hamlet = self.example_user("hamlet")

        # Make the realm allow permissive email changes, create a
        # link, and then lock the permissions down -- the change
        # should not be allowed when the link is followed.
        realm = hamlet.realm
        realm.disallow_disposable_email_addresses = False
        realm.emails_restricted_to_domains = False
        realm.save()

        self.login_user(hamlet)
        confirmation_url = self.generate_email_change_link("hamlet@mailnator.com")

        realm.disallow_disposable_email_addresses = True
        realm.save()

        response = self.client_get(confirmation_url)
        self.assertEqual(response.status_code, 400)
        self.assert_in_response("Please use your real email address.", response)

    def test_unauthorized_email_change_from_email_confirmation_link(self) -> None:
        new_email = "hamlet-new@zulip.com"
        user_profile = self.example_user("hamlet")
        self.login_user(user_profile)

        activation_url = self.generate_email_change_link(new_email)

        do_set_realm_property(
            user_profile.realm,
            "email_changes_disabled",
            True,
            acting_user=None,
        )

        response = self.client_get(activation_url)

        self.assertEqual(response.status_code, 400)
        self.assert_in_response(
            "Email address changes are disabled in this organization.", response
        )

    def test_post_invalid_email(self) -> None:
        invalid_emails = ["", "hamlet-new"]
        for email in invalid_emails:
            data = {"email": email}
            self.login("hamlet")
            url = "/json/settings"
            result = self.client_patch(url, data)
            self.assert_in_response("Invalid address", result)

    def test_post_same_email(self) -> None:
        data = {"email": self.example_email("hamlet")}
        self.login("hamlet")
        url = "/json/settings"
        result = self.client_patch(url, data)
        response_dict = self.assert_json_success(result)
        self.assertEqual("success", response_dict["result"])
        self.assertEqual("", response_dict["msg"])

    def test_change_delivery_email_end_to_end_with_admins_visibility(self) -> None:
        user_profile = self.example_user("hamlet")
        do_change_user_setting(
            user_profile,
            "email_address_visibility",
            UserProfile.EMAIL_ADDRESS_VISIBILITY_ADMINS,
            acting_user=None,
        )

        self.login_user(user_profile)
        old_email = user_profile.delivery_email
        new_email = "hamlet-new@zulip.com"
        obj = EmailChangeStatus.objects.create(
            new_email=new_email,
            old_email=old_email,
            user_profile=user_profile,
            realm=user_profile.realm,
        )
        url = create_confirmation_link(obj, Confirmation.EMAIL_CHANGE)
        response = self.client_get(url)

        self.assertEqual(response.status_code, 200)
        self.assert_in_success_response(
            ["This confirms that the email address for your Zulip"], response
        )
        user_profile = get_user_profile_by_id(user_profile.id)
        self.assertEqual(user_profile.delivery_email, new_email)
        self.assertEqual(user_profile.email, f"user{user_profile.id}@zulip.testserver")
        obj.refresh_from_db()
        self.assertEqual(obj.status, 1)
        with self.assertRaises(UserProfile.DoesNotExist):
            get_user(old_email, user_profile.realm)
        with self.assertRaises(UserProfile.DoesNotExist):
            get_user_by_delivery_email(old_email, user_profile.realm)
        self.assertEqual(get_user_by_delivery_email(new_email, user_profile.realm), user_profile)

    def test_configure_demo_organization_owner_email(self) -> None:
        desdemona = self.example_user("desdemona")
        desdemona.realm.demo_organization_scheduled_deletion_date = now() + timedelta(days=30)
        desdemona.realm.save()
        assert desdemona.realm.demo_organization_scheduled_deletion_date is not None

        self.login("desdemona")
        desdemona.delivery_email = ""
        desdemona.save()
        self.assertEqual(desdemona.delivery_email, "")

        data = {"email": "desdemona-new@zulip.com"}
        url = "/json/settings"
        self.assert_length(mail.outbox, 0)
        result = self.client_patch(url, data)
        self.assert_json_success(result)
        self.assert_length(mail.outbox, 1)

        email_message = mail.outbox[0]
        self.assertEqual(
            email_message.subject,
            "Verify your new email address for your demo Zulip organization",
        )
        body = email_message.body
        self.assertIn(
            "We received a request to add the email address",
            body,
        )
        self.assertEqual(self.email_envelope_from(email_message), settings.NOREPLY_EMAIL_ADDRESS)
        self.assertRegex(
            self.email_display_from(email_message),
            rf"^testserver account security <{self.TOKENIZED_NOREPLY_REGEX}>\Z",
        )
        self.assertEqual(email_message.extra_headers["List-Id"], "Zulip Dev <zulip.testserver>")

        confirmation_url = [s for s in body.split("\n") if s][2]
        response = self.client_get(confirmation_url, follow=True)
        self.assertEqual(response.status_code, 200)
        self.assert_in_success_response(["Set a new password"], response)

        user_profile = get_user_profile_by_id(desdemona.id)
        self.assertEqual(user_profile.delivery_email, "desdemona-new@zulip.com")