# This file is dual licensed under the terms of the Apache License, Version
# 2.0, and the BSD License. See the LICENSE file in the root of this repository
# for complete details.

from __future__ import absolute_import, division, print_function

from enum import Enum

from characteristic import attributes

from . import _constructs


class AlertLevel(Enum):
    WARNING = 1
    FATAL = 2


class AlertDescription(Enum):
    CLOSE_NOTIFY = 0
    UNEXPECTED_MESSAGE = 10
    BAD_RECORD_MAC = 20
    DECRYPTION_FAILED_RESERVED = 21
    RECORD_OVERFLOW = 22
    DECOMPRESSION_FAILURE = 30
    HANDSHAKE_FAILURE = 40
    NO_CERTIFICATE_RESERVED = 41
    BAD_CERTIFICATE = 42
    UNSUPPORTED_CERTIFICATE = 43
    CERTIFICATE_REVOKED = 44
    CERTIFICATE_EXPIRED = 45
    CERTIFICATE_UNKNOWN = 46
    ILLEGAL_PARAMETER = 47
    UNKNOWN_CA = 48
    ACCESS_DENIED = 49
    DECODE_ERROR = 50
    DECRYPT_ERROR = 51
    EXPORT_RESTRICTION_RESERVED = 60
    PROTOCOL_VERSION = 70
    INSUFFICIENT_SECURITY = 71
    INTERNAL_ERROR = 80
    USER_CANCELED = 90
    NO_RENEGOTIATION = 100
    UNSUPPORTED_EXTENSION = 110


@attributes(['level', 'description'])
class Alert(object):
    """
    An object representing an Alert message.
    """
    @classmethod
    def from_bytes(cls, bytes):
        """
        Parse an ``Alert`` struct.

        :param bytes: the bytes representing the input.
        :return: Alert object.
        """
        construct = _constructs.Alert.parse(bytes)
        return cls(
            level=AlertLevel(construct.level),
            description=AlertDescription(construct.description)
        )