# -*- coding: utf-8 -*-
# Copyright 2018 New Vector Ltd
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.

import hashlib
import hmac
import json

from mock import Mock

import synapse.rest.admin
from synapse.api.constants import UserTypes
from synapse.rest.client.v1 import login

from tests import unittest


class UserRegisterTestCase(unittest.HomeserverTestCase):

    servlets = [synapse.rest.admin.register_servlets_for_client_rest_resource]

    def make_homeserver(self, reactor, clock):

        self.url = "/_matrix/client/r0/admin/register"

        self.registration_handler = Mock()
        self.identity_handler = Mock()
        self.login_handler = Mock()
        self.device_handler = Mock()
        self.device_handler.check_device_registered = Mock(return_value="FAKE")

        self.datastore = Mock(return_value=Mock())
        self.datastore.get_current_state_deltas = Mock(return_value=(0, []))

        self.secrets = Mock()

        self.hs = self.setup_test_homeserver()

        self.hs.config.registration_shared_secret = "shared"

        self.hs.get_media_repository = Mock()
        self.hs.get_deactivate_account_handler = Mock()

        return self.hs

    def test_disabled(self):
        """
        If there is no shared secret, registration through this method will be
        prevented.
        """
        self.hs.config.registration_shared_secret = None

        request, channel = self.make_request("POST", self.url, b"{}")
        self.render(request)

        self.assertEqual(400, int(channel.result["code"]), msg=channel.result["body"])
        self.assertEqual(
            "Shared secret registration is not enabled", channel.json_body["error"]
        )

    def test_get_nonce(self):
        """
        Calling GET on the endpoint will return a randomised nonce, using the
        homeserver's secrets provider.
        """
        secrets = Mock()
        secrets.token_hex = Mock(return_value="abcd")

        self.hs.get_secrets = Mock(return_value=secrets)

        request, channel = self.make_request("GET", self.url)
        self.render(request)

        self.assertEqual(channel.json_body, {"nonce": "abcd"})

    def test_expired_nonce(self):
        """
        Calling GET on the endpoint will return a randomised nonce, which will
        only last for SALT_TIMEOUT (60s).
        """
        request, channel = self.make_request("GET", self.url)
        self.render(request)
        nonce = channel.json_body["nonce"]

        # 59 seconds
        self.reactor.advance(59)

        body = json.dumps({"nonce": nonce})
        request, channel = self.make_request("POST", self.url, body.encode("utf8"))
        self.render(request)

        self.assertEqual(400, int(channel.result["code"]), msg=channel.result["body"])
        self.assertEqual("username must be specified", channel.json_body["error"])

        # 61 seconds
        self.reactor.advance(2)

        request, channel = self.make_request("POST", self.url, body.encode("utf8"))
        self.render(request)

        self.assertEqual(400, int(channel.result["code"]), msg=channel.result["body"])
        self.assertEqual("unrecognised nonce", channel.json_body["error"])

    def test_register_incorrect_nonce(self):
        """
        Only the provided nonce can be used, as it's checked in the MAC.
        """
        request, channel = self.make_request("GET", self.url)
        self.render(request)
        nonce = channel.json_body["nonce"]

        want_mac = hmac.new(key=b"shared", digestmod=hashlib.sha1)
        want_mac.update(b"notthenonce\x00bob\x00abc123\x00admin")
        want_mac = want_mac.hexdigest()

        body = json.dumps(
            {
                "nonce": nonce,
                "username": "bob",
                "password": "abc123",
                "admin": True,
                "mac": want_mac,
            }
        )
        request, channel = self.make_request("POST", self.url, body.encode("utf8"))
        self.render(request)

        self.assertEqual(403, int(channel.result["code"]), msg=channel.result["body"])
        self.assertEqual("HMAC incorrect", channel.json_body["error"])

    def test_register_correct_nonce(self):
        """
        When the correct nonce is provided, and the right key is provided, the
        user is registered.
        """
        request, channel = self.make_request("GET", self.url)
        self.render(request)
        nonce = channel.json_body["nonce"]

        want_mac = hmac.new(key=b"shared", digestmod=hashlib.sha1)
        want_mac.update(
            nonce.encode("ascii") + b"\x00bob\x00abc123\x00admin\x00support"
        )
        want_mac = want_mac.hexdigest()

        body = json.dumps(
            {
                "nonce": nonce,
                "username": "bob",
                "password": "abc123",
                "admin": True,
                "user_type": UserTypes.SUPPORT,
                "mac": want_mac,
            }
        )
        request, channel = self.make_request("POST", self.url, body.encode("utf8"))
        self.render(request)

        self.assertEqual(200, int(channel.result["code"]), msg=channel.result["body"])
        self.assertEqual("@bob:test", channel.json_body["user_id"])

    def test_nonce_reuse(self):
        """
        A valid unrecognised nonce.
        """
        request, channel = self.make_request("GET", self.url)
        self.render(request)
        nonce = channel.json_body["nonce"]

        want_mac = hmac.new(key=b"shared", digestmod=hashlib.sha1)
        want_mac.update(nonce.encode("ascii") + b"\x00bob\x00abc123\x00admin")
        want_mac = want_mac.hexdigest()

        body = json.dumps(
            {
                "nonce": nonce,
                "username": "bob",
                "password": "abc123",
                "admin": True,
                "mac": want_mac,
            }
        )
        request, channel = self.make_request("POST", self.url, body.encode("utf8"))
        self.render(request)

        self.assertEqual(200, int(channel.result["code"]), msg=channel.result["body"])
        self.assertEqual("@bob:test", channel.json_body["user_id"])

        # Now, try and reuse it
        request, channel = self.make_request("POST", self.url, body.encode("utf8"))
        self.render(request)

        self.assertEqual(400, int(channel.result["code"]), msg=channel.result["body"])
        self.assertEqual("unrecognised nonce", channel.json_body["error"])

    def test_missing_parts(self):
        """
        Synapse will complain if you don't give nonce, username, password, and
        mac.  Admin and user_types are optional.  Additional checks are done for length
        and type.
        """

        def nonce():
            request, channel = self.make_request("GET", self.url)
            self.render(request)
            return channel.json_body["nonce"]

        #
        # Nonce check
        #

        # Must be present
        body = json.dumps({})
        request, channel = self.make_request("POST", self.url, body.encode("utf8"))
        self.render(request)

        self.assertEqual(400, int(channel.result["code"]), msg=channel.result["body"])
        self.assertEqual("nonce must be specified", channel.json_body["error"])

        #
        # Username checks
        #

        # Must be present
        body = json.dumps({"nonce": nonce()})
        request, channel = self.make_request("POST", self.url, body.encode("utf8"))
        self.render(request)

        self.assertEqual(400, int(channel.result["code"]), msg=channel.result["body"])
        self.assertEqual("username must be specified", channel.json_body["error"])

        # Must be a string
        body = json.dumps({"nonce": nonce(), "username": 1234})
        request, channel = self.make_request("POST", self.url, body.encode("utf8"))
        self.render(request)

        self.assertEqual(400, int(channel.result["code"]), msg=channel.result["body"])
        self.assertEqual("Invalid username", channel.json_body["error"])

        # Must not have null bytes
        body = json.dumps({"nonce": nonce(), "username": "abcd\u0000"})
        request, channel = self.make_request("POST", self.url, body.encode("utf8"))
        self.render(request)

        self.assertEqual(400, int(channel.result["code"]), msg=channel.result["body"])
        self.assertEqual("Invalid username", channel.json_body["error"])

        # Must not have null bytes
        body = json.dumps({"nonce": nonce(), "username": "a" * 1000})
        request, channel = self.make_request("POST", self.url, body.encode("utf8"))
        self.render(request)

        self.assertEqual(400, int(channel.result["code"]), msg=channel.result["body"])
        self.assertEqual("Invalid username", channel.json_body["error"])

        #
        # Password checks
        #

        # Must be present
        body = json.dumps({"nonce": nonce(), "username": "a"})
        request, channel = self.make_request("POST", self.url, body.encode("utf8"))
        self.render(request)

        self.assertEqual(400, int(channel.result["code"]), msg=channel.result["body"])
        self.assertEqual("password must be specified", channel.json_body["error"])

        # Must be a string
        body = json.dumps({"nonce": nonce(), "username": "a", "password": 1234})
        request, channel = self.make_request("POST", self.url, body.encode("utf8"))
        self.render(request)

        self.assertEqual(400, int(channel.result["code"]), msg=channel.result["body"])
        self.assertEqual("Invalid password", channel.json_body["error"])

        # Must not have null bytes
        body = json.dumps({"nonce": nonce(), "username": "a", "password": "abcd\u0000"})
        request, channel = self.make_request("POST", self.url, body.encode("utf8"))
        self.render(request)

        self.assertEqual(400, int(channel.result["code"]), msg=channel.result["body"])
        self.assertEqual("Invalid password", channel.json_body["error"])

        # Super long
        body = json.dumps({"nonce": nonce(), "username": "a", "password": "A" * 1000})
        request, channel = self.make_request("POST", self.url, body.encode("utf8"))
        self.render(request)

        self.assertEqual(400, int(channel.result["code"]), msg=channel.result["body"])
        self.assertEqual("Invalid password", channel.json_body["error"])

        #
        # user_type check
        #

        # Invalid user_type
        body = json.dumps(
            {
                "nonce": nonce(),
                "username": "a",
                "password": "1234",
                "user_type": "invalid",
            }
        )
        request, channel = self.make_request("POST", self.url, body.encode("utf8"))
        self.render(request)

        self.assertEqual(400, int(channel.result["code"]), msg=channel.result["body"])
        self.assertEqual("Invalid user type", channel.json_body["error"])


class UsersListTestCase(unittest.HomeserverTestCase):

    servlets = [
        synapse.rest.admin.register_servlets,
        login.register_servlets,
    ]
    url = "/_synapse/admin/v2/users"

    def prepare(self, reactor, clock, hs):
        self.admin_user = self.register_user("admin", "pass", admin=True)
        self.admin_user_tok = self.login("admin", "pass")

        self.register_user("user1", "pass1", admin=False)
        self.register_user("user2", "pass2", admin=False)

    def test_no_auth(self):
        """
        Try to list users without authentication.
        """
        request, channel = self.make_request("GET", self.url, b"{}")
        self.render(request)

        self.assertEqual(401, int(channel.result["code"]), msg=channel.result["body"])
        self.assertEqual("M_MISSING_TOKEN", channel.json_body["errcode"])

    def test_all_users(self):
        """
        List all users, including deactivated users.
        """
        request, channel = self.make_request(
            "GET",
            self.url + "?deactivated=true",
            b"{}",
            access_token=self.admin_user_tok,
        )
        self.render(request)

        self.assertEqual(200, int(channel.result["code"]), msg=channel.result["body"])
        self.assertEqual(3, len(channel.json_body["users"]))


class UserRestTestCase(unittest.HomeserverTestCase):

    servlets = [
        synapse.rest.admin.register_servlets,
        login.register_servlets,
    ]

    def prepare(self, reactor, clock, hs):
        self.store = hs.get_datastore()

        self.url = "/_synapse/admin/v2/users/@bob:test"

        self.admin_user = self.register_user("admin", "pass", admin=True)
        self.admin_user_tok = self.login("admin", "pass")

        self.other_user = self.register_user("user", "pass")
        self.other_user_token = self.login("user", "pass")

    def test_requester_is_no_admin(self):
        """
        If the user is not a server admin, an error is returned.
        """
        self.hs.config.registration_shared_secret = None

        request, channel = self.make_request(
            "GET", self.url, access_token=self.other_user_token,
        )
        self.render(request)

        self.assertEqual(403, int(channel.result["code"]), msg=channel.result["body"])
        self.assertEqual("You are not a server admin", channel.json_body["error"])

        request, channel = self.make_request(
            "PUT", self.url, access_token=self.other_user_token, content=b"{}",
        )
        self.render(request)

        self.assertEqual(403, int(channel.result["code"]), msg=channel.result["body"])
        self.assertEqual("You are not a server admin", channel.json_body["error"])

    def test_requester_is_admin(self):
        """
        If the user is a server admin, a new user is created.
        """
        self.hs.config.registration_shared_secret = None

        body = json.dumps({"password": "abc123", "admin": True})

        # Create user
        request, channel = self.make_request(
            "PUT",
            self.url,
            access_token=self.admin_user_tok,
            content=body.encode(encoding="utf_8"),
        )
        self.render(request)

        self.assertEqual(201, int(channel.result["code"]), msg=channel.result["body"])
        self.assertEqual("@bob:test", channel.json_body["name"])
        self.assertEqual("bob", channel.json_body["displayname"])

        # Get user
        request, channel = self.make_request(
            "GET", self.url, access_token=self.admin_user_tok,
        )
        self.render(request)

        self.assertEqual(200, int(channel.result["code"]), msg=channel.result["body"])
        self.assertEqual("@bob:test", channel.json_body["name"])
        self.assertEqual("bob", channel.json_body["displayname"])
        self.assertEqual(1, channel.json_body["admin"])
        self.assertEqual(0, channel.json_body["is_guest"])
        self.assertEqual(0, channel.json_body["deactivated"])

        # Change password
        body = json.dumps({"password": "hahaha"})

        request, channel = self.make_request(
            "PUT",
            self.url,
            access_token=self.admin_user_tok,
            content=body.encode(encoding="utf_8"),
        )
        self.render(request)

        self.assertEqual(200, int(channel.result["code"]), msg=channel.result["body"])

        # Modify user
        body = json.dumps({"displayname": "foobar", "deactivated": True})

        request, channel = self.make_request(
            "PUT",
            self.url,
            access_token=self.admin_user_tok,
            content=body.encode(encoding="utf_8"),
        )
        self.render(request)

        self.assertEqual(200, int(channel.result["code"]), msg=channel.result["body"])
        self.assertEqual("@bob:test", channel.json_body["name"])
        self.assertEqual("foobar", channel.json_body["displayname"])
        self.assertEqual(True, channel.json_body["deactivated"])

        # Get user
        request, channel = self.make_request(
            "GET", self.url, access_token=self.admin_user_tok,
        )
        self.render(request)

        self.assertEqual(200, int(channel.result["code"]), msg=channel.result["body"])
        self.assertEqual("@bob:test", channel.json_body["name"])
        self.assertEqual("foobar", channel.json_body["displayname"])
        self.assertEqual(1, channel.json_body["admin"])
        self.assertEqual(0, channel.json_body["is_guest"])
        self.assertEqual(1, channel.json_body["deactivated"])