# (c) 2005 Ian Bicking and contributors; written for Paste (http://pythonpaste.org)
# Licensed under the MIT license: http://www.opensource.org/licenses/mit-license.php
from paste.deploy.compat import basestring


truthy = frozenset(['true', 'yes', 'on', 'y', 't', '1'])
falsy = frozenset(['false', 'no', 'off', 'n', 'f', '0'])


def asbool(obj):
    if isinstance(obj, basestring):
        obj = obj.strip().lower()
        if obj in truthy:
            return True
        elif obj in falsy:
            return False
        else:
            raise ValueError("String is not true/false: %r" % obj)
    return bool(obj)


def asint(obj):
    try:
        return int(obj)
    except (TypeError, ValueError):
        raise ValueError("Bad integer value: %r" % obj)


def aslist(obj, sep=None, strip=True):
    if isinstance(obj, basestring):
        lst = obj.split(sep)
        if strip:
            lst = [v.strip() for v in lst]
        return lst
    elif isinstance(obj, (list, tuple)):
        return obj
    elif obj is None:
        return []
    else:
        return [obj]
