#Copyright 2013: Mirantis Inc.
# All Rights Reserved.
#
#    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.

# bottlenecks comment: this is a modified copy of rally/rally/common/utils.py

import os
import sys
from oslo_utils import importutils

import utils


# Decorator for cli-args
def cliargs(*args, **kwargs):
    def _decorator(func):
        func.__dict__.setdefault('arguments', []).insert(0, (args, kwargs))
        return func
    return _decorator


def itersubclasses(cls, _seen=None):
    """Generator over all subclasses of a given class in depth first order."""

    if not isinstance(cls, type):
        raise TypeError("itersubclasses must be called with "
                        "new-style classes, not %.100r" % cls)
    _seen = _seen or set()
    try:
        subs = cls.__subclasses__()
    except TypeError:   # fails only when cls is type
        subs = cls.__subclasses__(cls)
    for sub in subs:
        if sub not in _seen:
            _seen.add(sub)
            yield sub
            for sub in itersubclasses(sub, _seen):
                yield sub


def try_append_module(name, modules):
    if name not in modules:
        modules[name] = importutils.import_module(name)


def import_modules_from_package(package):
    """Import modules from package and append into sys.modules

    :param: package - Full package name. For example: rally.deploy.engines
    """
    path = [os.path.dirname(utils.__file__), ".."] + package.split(".")
    path = os.path.join(*path)
    for root, dirs, files in os.walk(path):
        for filename in files:
            if filename.startswith("__") or not filename.endswith(".py"):
                continue
            new_package = ".".join(root.split(os.sep)).split("....")[1]
            module_name = "%s.%s" % (new_package, filename[:-3])
            try_append_module(module_name, sys.modules)