# Copyright (c) 2023, 2026, Oracle and/or its affiliates.
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License, version 2.0, as
# published by the Free Software Foundation.
#
# This program is designed to work with certain software (including
# but not limited to OpenSSL) that is licensed under separate terms,
# as designated in a particular file or component or in included license
# documentation. The authors of MySQL hereby grant you an
# additional permission to link the program and your derivative works
# with the separately licensed software that they have either included with
# the program or referenced in the documentation.
#
# Without limiting anything contained in the foregoing, this file,
# which is part of MySQL Connector/Python, is also subject to the
# Universal FOSS Exception, version 1.0, a copy of which can be found at
# http://oss.oracle.com/licenses/universal-foss-exception.
#
# This program 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, version 2.0, for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software Foundation, Inc.,
# 51 Franklin St, Fifth Floor, Boston, MA 02110-1301  USA

"""SHA256 Password Authentication Plugin."""

from typing import TYPE_CHECKING, Any, Optional

from .. import errors
from ..logger import logger
from . import MySQLAuthPlugin

if TYPE_CHECKING:
    from ..network import MySQLSocket

AUTHENTICATION_PLUGIN_CLASS = "MySQLSHA256PasswordAuthPlugin"


class MySQLSHA256PasswordAuthPlugin(MySQLAuthPlugin):
    """Class implementing the MySQL SHA256 authentication plugin

    Note that encrypting using RSA is not supported since the Python
    Standard Library does not provide this OpenSSL functionality.
    """

    def _prepare_password(self) -> bytes:
        """Prepare and return password as as clear text.

        Returns:
            password (bytes): Prepared password.
        """
        return self._password.encode() + b"\x00"

    @property
    def name(self) -> str:
        """Plugin official name."""
        return "sha256_password"

    @property
    def requires_ssl(self) -> bool:
        """Signals whether or not SSL is required."""
        return True

    def auth_response(self, auth_data: bytes, **kwargs: Any) -> Optional[bytes]:
        """Return the prepared password to send to MySQL.

        Raises:
            InterfaceError: When SSL is required by not enabled.

        Returns:
            str: The prepared password.
        """
        if self.requires_ssl and not self.ssl_enabled:
            raise errors.InterfaceError(f"{self.name} requires SSL")
        return self._prepare_password()

    def auth_switch_response(
        self, sock: "MySQLSocket", auth_data: bytes, **kwargs: Any
    ) -> bytes:
        """Handles server's `auth switch request` response.

        Args:
            sock: Pointer to the socket connection.
            auth_data: Plugin provided data (extracted from a packet
                       representing an `auth switch request` response).
            kwargs: Custom configuration to be passed to the auth plugin
                    when invoked. The parameters defined here will override the ones
                    defined in the auth plugin itself.

        Returns:
            packet: Last server's response after back-and-forth
                    communication.
        """
        response = self.auth_response(auth_data, **kwargs)
        if response is None:
            raise errors.InterfaceError("Got a NULL auth response")

        logger.debug("# request: %s size: %s", response, len(response))
        sock.send(response)

        pkt = bytes(sock.recv())
        logger.debug("# server response packet: %s", pkt)

        return pkt
