# Copyright © Cloud Linux GmbH & Cloud Linux Software, Inc 2010-2018 All Rights Reserved
#
# Licensed under CLOUD LINUX LICENSE AGREEMENT
# https://cloudlinux.com/docs/LICENCE.TXT
#
import logging
import inspect
import os
import sys
from dataclasses import dataclass

from clcommon.utils import is_ubuntu, run_command, ExternalProgramFailed


def _get_default_args(func):
    """
    Get dict with key-value pairs of default
    argument values
    """
    signature = inspect.signature(func)
    return {
        k: v.default
        for k, v in signature.parameters.items()
        if v.default is not inspect.Parameter.empty
    }


def _get_args_dict(func, args, kwargs):
    """
    Get all func arguments including defaults, args and kwargs
    """
    func_args = {}

    func_args.update(_get_default_args(func))
    func_args.update(dict(zip(func.__code__.co_varnames, args)))
    func_args.update(kwargs)

    return func_args


def task(name):
    """
    Simple wrapper that logs execution begin and end
    """
    def decorator(func):
        def wrapped_func(*args, **kwargs):
            func_args = _get_args_dict(func, args, kwargs)
            logging.info(name.format(**func_args))
            try:
                func(*args, **kwargs)
            except Exception:
                logging.exception('FAILED to %s', name.format(**func_args))
                raise
        return wrapped_func
    return decorator


def setup_logger(logger_name, log_file):
    """
    Logger setup for all modules
    """
    app_logger = logging.getLogger(logger_name)
    app_logger.setLevel(logging.DEBUG)
    try:
        fh = logging.FileHandler(log_file)
    except IOError:
        pass
    else:
        fh.formatter = logging.Formatter(
            '[%(levelname)s | %(asctime)s]: %(message)s')
        fh.level = logging.DEBUG
        app_logger.addHandler(fh)
    for handler in app_logger.handlers:
        if isinstance(handler, logging.StreamHandler) and handler.stream == sys.stderr:
            handler.formatter = logging.Formatter('[cloudlinux-customizer]: %(message)s')
            handler.level = logging.INFO
    return app_logger


@dataclass
class RunResult:
    """
    Describes process call result
    """
    exitcode: int
    stdout: str
    stderr: str


def run(cmd, fail_ok=False):
    """
    Just a wrapper above run_command that provides some
    cool logging of what happens in subprocess
    """
    logging.debug('Running %s', ' '.join(cmd))

    env_data = os.environ.copy()
    # Force C locale to ensure consistent output across all systems
    env_data['LC_ALL'] = 'C'
    if is_ubuntu():
        # Prevent debconf from asking questions
        env_data['DEBIAN_FRONTEND'] = 'noninteractive'

    try:
        exitcode, stdout, stderr = run_command(
            cmd,
            env_data=env_data,
            return_full_output=True,
        )
        logging.debug('Stdout: %s', stdout)
        logging.debug('Stderr: %s', stderr)
        return RunResult(exitcode, stdout, stderr)
    except ExternalProgramFailed as e:
        if not fail_ok:
            logging.error(str(e))
        return RunResult(-1, None, None)