# coding=utf-8
#
# Copyright © Cloud Linux GmbH & Cloud Linux Software, Inc 2010-2020 All Rights Reserved
#
# Licensed under CLOUD LINUX LICENSE AGREEMENT
# http://cloudlinux.com/docs/LICENCE.TXT
#

import os
import subprocess
import warnings
from enum import Enum
from typing import AnyStr

from jwt import exceptions

from clcommon.lib.consts import CLN_JWT_TOKEN_PATH, CL_EDITION_FILE_FOR_USERS
from clcommon.lib.jwt_token import read_jwt, decode_jwt, jwt_token_check
from clcommon.clexception import FormattedException
from clcommon.clcagefs import in_cagefs
# The function below used to be in this module, but were moved to clcommon.utils
# So, importing them just for backward compatibility
from clcommon.utils import get_os_version, is_ubuntu, is_secureboot_enabled  # NOQA

CL_SOLO_EDITION_FILE_MARKER = '/etc/cloudlinux-edition-solo'
CL_ADMIN_EDITION_FILE_MARKER = '/etc/cloudlinux-edition-admin'

SHARED_PRO_EDITION_HUMAN_READABLE = 'CloudLinux OS Shared Pro'
SHARED_EDITION_HUMAN_READABLE = 'CloudLinux OS Shared'
SOLO_EDITION_HUMAN_READABLE = 'CloudLinux OS Solo'
ADMIN_EDITION_HUMAN_READABLE = 'CloudLinux OS Admin'


class SupportedEditions(Enum):
    """
    Keeps supported CloudLinux editions
    """

    SOLO = 'solo'
    SHARED = 'shared'
    SHARED_PRO = 'shared_pro'
    ADMIN = 'admin'


class CLEditionDetectionError(FormattedException):
    def __init__(self, message, **context):
        FormattedException.__init__(self, {
            'message': message,
            'context': context
        })


HUMAN_READABLE_TOKEN_EDITION_PAIRS = {
    SOLO_EDITION_HUMAN_READABLE: SupportedEditions.SOLO.value,
    SHARED_PRO_EDITION_HUMAN_READABLE: SupportedEditions.SHARED_PRO.value,
    SHARED_EDITION_HUMAN_READABLE: SupportedEditions.SHARED.value,
    ADMIN_EDITION_HUMAN_READABLE: SupportedEditions.ADMIN.value
}


class CLEditions:

    @staticmethod
    def get_from_jwt(token=None, verify_exp=True):
        """
        Note: be careful when modifying this method.
        Passing token in is used in X-Ray,
        ask @dkavchuk or someone else from C-Projects team for details
        :param token:
        :param verify_exp:
        :return:
        """
        if token is None:
            token = read_jwt(CLN_JWT_TOKEN_PATH)
        try:
            jwt = decode_jwt(token, verify_exp=verify_exp)
        except exceptions.PyJWTError as e:
            raise CLEditionDetectionError(
                f'Unable to detect edition from jwt token: {CLN_JWT_TOKEN_PATH}. '
                f'Please, make sure it is not broken, error: {e}'
            ) from e
        try:
            return jwt['edition']
        except KeyError as e:
            # fallback for old format of tokens
            cl_plus = jwt.get('cl_plus')
            if cl_plus is None:
                raise CLEditionDetectionError(
                    f'Unable to detect edition from jwt token: {CLN_JWT_TOKEN_PATH}. '
                    f'Please, make sure it is not broken, error: not enough fields for detection'
                ) from e
            return SupportedEditions.SHARED_PRO.value if cl_plus else SupportedEditions.SHARED.value

    @staticmethod
    def is_package_installed(package_name):
        with subprocess.Popen(
            ['rpm', '-q', package_name],
            stdout=subprocess.PIPE,
            stderr=subprocess.PIPE,
            text=True,
            env={**os.environ, **{'LC_ALL': 'C'}},
        ) as proc:
            out, err = proc.communicate()
            if proc.returncode != 0:
                if 'is not installed' in out:
                    return False

                raise CLEditionDetectionError(
                    f'Unable to check if package {package_name} is installed, '
                    f'reason: {out}, {err}'
                )
        return True

    @classmethod
    def get_cl_edition(
        cls,
        skip_jwt_check=False,
        skip_marker_check=False,
        raw_jwt=None,
        verify_exp=True,
    ) -> str | None:
        """
        1. Try to detect CL edition from JWT token;
            If edition field is in token -> return edition
            If edition field is not present -> recheck via cl_plus flag (see get_from_jwt)
            If token is broken -> raise an error about it
        2. Try to detect edition from files.
            If JWT edition retreival was attempted and failed, or if we're in cagefs
            -> get edition from CL_EDITION_FILE_FOR_USERS
            If a edition marker file for Solo or Admin edition is present -> return corresponding edition
            Otherwise, fall back to CL_EDITION_FILE_FOR_USERS again
            Detection from marker files may be switched off using the `skip_marker_check` parameter.

        @param skip_jwt_check: if True, skip checking JWT token for edition.
        @param skip_marker_check: if True, skip checking marker files for edition.
        @param raw_jwt: raw JWT token to use for edition detection. If None, token will be read from file.
        @param verify_exp: if True, verify JWT token expiration time.
        @return: Edition of CloudLinux OS or None if edition could not be determined.

        Note: be careful when modifying this method.
        It is used in X-Ray, ask @dkavchuk or someone else from C-Projects team for details.
        """
        # Skipping both jwt and file checks is not allowed
        if skip_jwt_check and skip_marker_check:
            raise CLEditionDetectionError(
                "Unable to detect edition: neither jwt token check, no file marker check enabled"
            )

        # If we have a valid JWT token, try to get edition from it
        if not skip_jwt_check and os.path.isfile(CLN_JWT_TOKEN_PATH):
            try:
                edition = cls.get_from_jwt(token=raw_jwt, verify_exp=verify_exp)
            except PermissionError:
                edition = user_cl_edition()
            if edition:
                return edition

        # If user is in cagefs, look at the CL_EDITION_FILE_FOR_USERS file first
        if in_cagefs():
            return user_cl_edition()

        # Otherwise, check for edition marker files
        if not skip_marker_check:
            # jwt has no 'edition' field -> ensure it really is Solo via file
            if os.path.isfile(CL_SOLO_EDITION_FILE_MARKER):
                return SupportedEditions.SOLO.value
            elif os.path.isfile(CL_ADMIN_EDITION_FILE_MARKER):
                return SupportedEditions.ADMIN.value
            # Finally, if no marker files are present, try CL_EDITION_FILE_FOR_USERS
            return user_cl_edition()

        # Couldn't detect edition through any means - return None
        return None


def is_cl_solo_edition(skip_jwt_check=True, skip_marker_check=False, verify_exp=True):
    """
    Allow skip_jwt_check ONLY if it not critical when license is not valid
    Use skip_marker_check=True when validity of license is critical
     and fallback to file is not applicable
    Note: be careful when modifying this method.
    It is used in X-Ray and SSA,
    ask @dkavchuk or someone else from C-Projects team for details
    """

    edition = CLEditions.get_cl_edition(
        skip_jwt_check=skip_jwt_check,
        skip_marker_check=skip_marker_check,
        verify_exp=verify_exp
    )
    return edition is not None and edition == SupportedEditions.SOLO.value


def is_cl_shared_edition(skip_jwt_check=False, skip_marker_check=False, verify_exp=True):
    """
    Allow skip_jwt_check ONLY if it not critical when license is not valid
    Use skip_marker_check=True when validity of license is critical
     and fallback to file is not applicable
    """

    edition = CLEditions.get_cl_edition(
        skip_jwt_check=skip_jwt_check,
        skip_marker_check=skip_marker_check,
        verify_exp=verify_exp
    )
    return edition is not None and edition == SupportedEditions.SHARED.value


def is_cl_shared_pro_edition(skip_jwt_check=False,
                             skip_marker_check=False,
                             verify_exp=True):
    """
    Allow skip_jwt_check ONLY if it not critical when license is not valid
    Use skip_marker_check=True when validity of license is critical
     and fallback to file is not applicable
    """

    edition = CLEditions.get_cl_edition(
        skip_jwt_check=skip_jwt_check,
        skip_marker_check=skip_marker_check,
        verify_exp=verify_exp
    )
    return edition is not None and edition == SupportedEditions.SHARED_PRO.value


def is_cl_shared_pro_edition_safely(**kwargs):
    """
    Supress edition checking error and returns False
    """
    try:
        return is_cl_shared_pro_edition(**kwargs)
    except CLEditionDetectionError:
        return False


def is_cl_admin_edition(skip_jwt_check=False,
                        skip_marker_check=False,
                        verify_exp=True):
    """
    Allow skip_jwt_check ONLY if it not critical when license is not valid
    Use skip_marker_check=True when validity of license is critical
     and fallback to file is not applicable
    """

    edition = CLEditions.get_cl_edition(
        skip_jwt_check=skip_jwt_check,
        skip_marker_check=skip_marker_check,
        verify_exp=verify_exp
    )
    return edition is not None and edition == SupportedEditions.ADMIN.value


def get_cl_edition_readable() -> AnyStr:
    """
    Function returns current edition of CL:
    - CloudLinux OS Shared
    - CloudLinux OS Shared Pro
    - CloudLinux OS Solo
    - Error string
    """

    try:
        if is_cl_solo_edition(skip_jwt_check=True):
            return SOLO_EDITION_HUMAN_READABLE
        elif is_cl_admin_edition(skip_jwt_check=True):
            return ADMIN_EDITION_HUMAN_READABLE
    except CLEditionDetectionError:
        return SHARED_EDITION_HUMAN_READABLE

    success_flag, error_message, _ = jwt_token_check()

    # This error message indicates that user could not read jwt.token because not enough privileges
    # We have to check existence of token file, to be sure that privilege error acquired
    if 'read error' in error_message and (os.path.isfile(CLN_JWT_TOKEN_PATH) or in_cagefs()):
        with open(CL_EDITION_FILE_FOR_USERS, 'r', encoding='utf-8') as f:
            return f.read().strip()

    if success_flag:
        return SHARED_PRO_EDITION_HUMAN_READABLE
    else:
        return SHARED_EDITION_HUMAN_READABLE


def print_skip_message_on_solo():
    """Just print skip message"""

    warnings.warn(
        'as part of unification effort, features might not map directly to editions',
        DeprecationWarning,
    )
    print('CloudLinux Solo edition detected! \n'
          'Command is skipped, because it is unsupported and unneeded on current edition')


# NOTE(vlebedev): To properly avoid circular imports, these 2 functions' implementations
#                 are moved to "utils" submodule of "clcommon.cpapi" as it is the level
#                 where all necessary panel stuff is imported and constructed and which
#                 uses "clcommon.lib" module as a dependency. In other words "clcommon.lib" lays
#                 lower in the modules hierarchy and should not import from "clcommon.cpapi").
def skip_without_lve():
    warnings.warn(
        'since v3.4.1 use "clcommon.cpapi.utils:skip_without_lve" instead',
        DeprecationWarning,
    )
    from clcommon.cpapi.utils import skip_without_lve  # pylint: disable=cyclic-import,import-outside-toplevel
    return skip_without_lve()


def lve_supported_or_exit(f):
    warnings.warn(
        'since v3.4.1 use "clcommon.cpapi.utils:lve_supported_or_exit" instead',
        DeprecationWarning,
    )
    from clcommon.cpapi.utils import lve_supported_or_exit  # pylint: disable=cyclic-import,import-outside-toplevel
    return lve_supported_or_exit(f)


def user_cl_edition():
    """
    This function is used as a workaround for users to be able to get the CL Edition.
    Crontab will write output of `cldetect --detect-edition` command to CL_EDITION_FILE_FOR_USERS, with 0644 permission.
    """
    if os.path.exists(CL_EDITION_FILE_FOR_USERS):
        with open(CL_EDITION_FILE_FOR_USERS, "r", encoding="utf-8") as f:
            edition = f.read().strip()

        return HUMAN_READABLE_TOKEN_EDITION_PAIRS.get(edition)
    return None


def is_container() -> bool:
    """
    Determines is this system running inside container
    """
    return os.path.exists('/etc/cloudlinux-container')