# Copyright 2015, 2016 OpenMarket Ltd
# Copyright 2021 The Matrix.org Foundation C.I.C.
#
# 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 argparse
from typing import Any, Optional

from synapse.api.constants import RoomCreationPreset
from synapse.config._base import Config, ConfigError
from synapse.types import JsonDict, RoomAlias, UserID
from synapse.util.stringutils import random_string_with_symbols, strtobool


class RegistrationConfig(Config):
    section = "registration"

    def read_config(self, config: JsonDict, **kwargs: Any) -> None:
        self.enable_registration = strtobool(
            str(config.get("enable_registration", False))
        )
        if "disable_registration" in config:
            self.enable_registration = not strtobool(
                str(config["disable_registration"])
            )

        self.enable_registration_without_verification = strtobool(
            str(config.get("enable_registration_without_verification", False))
        )

        self.registrations_require_3pid = config.get("registrations_require_3pid", [])
        self.allowed_local_3pids = config.get("allowed_local_3pids", [])
        self.enable_3pid_lookup = config.get("enable_3pid_lookup", True)
        self.registration_requires_token = config.get(
            "registration_requires_token", False
        )
        self.enable_registration_token_3pid_bypass = config.get(
            "enable_registration_token_3pid_bypass", False
        )
        self.registration_shared_secret = config.get("registration_shared_secret")

        self.bcrypt_rounds = config.get("bcrypt_rounds", 12)

        account_threepid_delegates = config.get("account_threepid_delegates") or {}
        self.account_threepid_delegate_email = account_threepid_delegates.get("email")
        self.account_threepid_delegate_msisdn = account_threepid_delegates.get("msisdn")
        self.default_identity_server = config.get("default_identity_server")
        self.allow_guest_access = config.get("allow_guest_access", False)

        if config.get("invite_3pid_guest", False):
            raise ConfigError("invite_3pid_guest is no longer supported")

        self.auto_join_rooms = config.get("auto_join_rooms", [])
        for room_alias in self.auto_join_rooms:
            if not RoomAlias.is_valid(room_alias):
                raise ConfigError("Invalid auto_join_rooms entry %s" % (room_alias,))

        # Options for creating auto-join rooms if they do not exist yet.
        self.autocreate_auto_join_rooms = config.get("autocreate_auto_join_rooms", True)
        self.autocreate_auto_join_rooms_federated = config.get(
            "autocreate_auto_join_rooms_federated", True
        )
        self.autocreate_auto_join_room_preset = (
            config.get("autocreate_auto_join_room_preset")
            or RoomCreationPreset.PUBLIC_CHAT
        )
        self.auto_join_room_requires_invite = self.autocreate_auto_join_room_preset in {
            RoomCreationPreset.PRIVATE_CHAT,
            RoomCreationPreset.TRUSTED_PRIVATE_CHAT,
        }

        # Pull the creator/inviter from the configuration, this gets used to
        # send invites for invite-only rooms.
        mxid_localpart = config.get("auto_join_mxid_localpart")
        self.auto_join_user_id = None
        if mxid_localpart:
            # Convert the localpart to a full mxid.
            self.auto_join_user_id = UserID(
                mxid_localpart, self.root.server.server_name
            ).to_string()

        if self.autocreate_auto_join_rooms:
            # Ensure the preset is a known value.
            if self.autocreate_auto_join_room_preset not in {
                RoomCreationPreset.PUBLIC_CHAT,
                RoomCreationPreset.PRIVATE_CHAT,
                RoomCreationPreset.TRUSTED_PRIVATE_CHAT,
            }:
                raise ConfigError("Invalid value for autocreate_auto_join_room_preset")
            # If the preset requires invitations to be sent, ensure there's a
            # configured user to send them from.
            if self.auto_join_room_requires_invite:
                if not mxid_localpart:
                    raise ConfigError(
                        "The configuration option `auto_join_mxid_localpart` is required if "
                        "`autocreate_auto_join_room_preset` is set to private_chat or trusted_private_chat, such that "
                        "Synapse knows who to send invitations from. Please "
                        "configure `auto_join_mxid_localpart`."
                    )

        self.auto_join_rooms_for_guests = config.get("auto_join_rooms_for_guests", True)

        self.enable_set_displayname = config.get("enable_set_displayname", True)
        self.enable_set_avatar_url = config.get("enable_set_avatar_url", True)
        self.enable_3pid_changes = config.get("enable_3pid_changes", True)

        self.disable_msisdn_registration = config.get(
            "disable_msisdn_registration", False
        )

        session_lifetime = config.get("session_lifetime")
        if session_lifetime is not None:
            session_lifetime = self.parse_duration(session_lifetime)
        self.session_lifetime = session_lifetime

        # The `refreshable_access_token_lifetime` applies for tokens that can be renewed
        # using a refresh token, as per MSC2918.
        # If it is `None`, the refresh token mechanism is disabled.
        refreshable_access_token_lifetime = config.get(
            "refreshable_access_token_lifetime",
            "5m",
        )
        if refreshable_access_token_lifetime is not None:
            refreshable_access_token_lifetime = self.parse_duration(
                refreshable_access_token_lifetime
            )
        self.refreshable_access_token_lifetime: Optional[
            int
        ] = refreshable_access_token_lifetime

        if (
            self.session_lifetime is not None
            and "refreshable_access_token_lifetime" in config
        ):
            if self.session_lifetime < self.refreshable_access_token_lifetime:
                raise ConfigError(
                    "Both `session_lifetime` and `refreshable_access_token_lifetime` "
                    "configuration options have been set, but `refreshable_access_token_lifetime` "
                    " exceeds `session_lifetime`!"
                )

        # The `nonrefreshable_access_token_lifetime` applies for tokens that can NOT be
        # refreshed using a refresh token.
        # If it is None, then these tokens last for the entire length of the session,
        # which is infinite by default.
        # The intention behind this configuration option is to help with requiring
        # all clients to use refresh tokens, if the homeserver administrator requires.
        nonrefreshable_access_token_lifetime = config.get(
            "nonrefreshable_access_token_lifetime",
            None,
        )
        if nonrefreshable_access_token_lifetime is not None:
            nonrefreshable_access_token_lifetime = self.parse_duration(
                nonrefreshable_access_token_lifetime
            )
        self.nonrefreshable_access_token_lifetime = nonrefreshable_access_token_lifetime

        if (
            self.session_lifetime is not None
            and self.nonrefreshable_access_token_lifetime is not None
        ):
            if self.session_lifetime < self.nonrefreshable_access_token_lifetime:
                raise ConfigError(
                    "Both `session_lifetime` and `nonrefreshable_access_token_lifetime` "
                    "configuration options have been set, but `nonrefreshable_access_token_lifetime` "
                    " exceeds `session_lifetime`!"
                )

        refresh_token_lifetime = config.get("refresh_token_lifetime")
        if refresh_token_lifetime is not None:
            refresh_token_lifetime = self.parse_duration(refresh_token_lifetime)
        self.refresh_token_lifetime: Optional[int] = refresh_token_lifetime

        if (
            self.session_lifetime is not None
            and self.refresh_token_lifetime is not None
        ):
            if self.session_lifetime < self.refresh_token_lifetime:
                raise ConfigError(
                    "Both `session_lifetime` and `refresh_token_lifetime` "
                    "configuration options have been set, but `refresh_token_lifetime` "
                    " exceeds `session_lifetime`!"
                )

        # The fallback template used for authenticating using a registration token
        self.registration_token_template = self.read_template("registration_token.html")

        # The success template used during fallback auth.
        self.fallback_success_template = self.read_template("auth_success.html")

        self.inhibit_user_in_use_error = config.get("inhibit_user_in_use_error", False)

    def generate_config_section(
        self, generate_secrets: bool = False, **kwargs: Any
    ) -> str:
        if generate_secrets:
            registration_shared_secret = 'registration_shared_secret: "%s"' % (
                random_string_with_symbols(50),
            )
            return registration_shared_secret
        else:
            return ""

    @staticmethod
    def add_arguments(parser: argparse.ArgumentParser) -> None:
        reg_group = parser.add_argument_group("registration")
        reg_group.add_argument(
            "--enable-registration",
            action="store_true",
            default=None,
            help="Enable registration for new users.",
        )

    def read_arguments(self, args: argparse.Namespace) -> None:
        if args.enable_registration is not None:
            self.enable_registration = strtobool(str(args.enable_registration))
