import distutils.util
import functools
import inspect

from fabric.decorators import task


class bool_args(object):
    def __init__(self, *bool_arg_names):
        self.bool_arg_names = bool_arg_names

    def __call__(self, f):
        @functools.wraps(f)
        def wrapper(*args, **kwargs):
            callargs = inspect.getcallargs(f, *args, **kwargs)
            for k, v in callargs.viewitems():
                if k in self.bool_arg_names and not isinstance(v, bool):
                    callargs[k] = bool(distutils.util.strtobool(v))
            return f(**callargs)
        return wrapper


@task
@bool_args('my_bool_arg')
def do_something(my_bool_arg=True):
  assert isinstance(my_bool_arg, bool)