##############################################################################
#
# Copyright (c) 2002 Zope Foundation and Contributors.
#
# This software is subject to the provisions of the Zope Public License,
# Version 2.1 (ZPL).  A copy of the ZPL should accompany this distribution.
# THIS SOFTWARE IS PROVIDED "AS IS" AND ANY AND ALL EXPRESS OR IMPLIED
# WARRANTIES ARE DISCLAIMED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
# WARRANTIES OF TITLE, MERCHANTABILITY, AGAINST INFRINGEMENT, AND FITNESS
# FOR A PARTICULAR PURPOSE
#
##############################################################################
"""General exceptions that wish they were standard exceptions

These exceptions are so general purpose that they don't belong in Zope
application-specific packages.
"""

from types import ClassType
import warnings

from zope.interface import implements
from zope.interface.common.interfaces import IException
from zope.publisher.interfaces import INotFound
from zope.security.interfaces import IForbidden
from zExceptions.unauthorized import Unauthorized


class BadRequest(Exception):
    implements(IException)


class InternalError(Exception):
    implements(IException)


class NotFound(Exception):
    implements(INotFound)


class Forbidden(Exception):
    implements(IForbidden)


class MethodNotAllowed(Exception):
    pass


class Redirect(Exception):
    pass


def convertExceptionType(name):
    import zExceptions
    etype = None
    if name in __builtins__:
        etype = __builtins__[name]
    elif hasattr(zExceptions, name):
        etype = getattr(zExceptions, name)
    if (etype is not None and
        isinstance(etype, (type, ClassType)) and
        issubclass(etype, Exception)):
        return etype


def upgradeException(t, v):
    # If a string exception is found, convert it to an equivalent
    # exception defined either in builtins or zExceptions. If none of
    # that works, tehn convert it to an InternalError and keep the
    # original exception name as part of the exception value.
    if isinstance(t, basestring):
        warnings.warn('String exceptions are deprecated starting '
                    'with Python 2.5 and will be removed in a '
                    'future release', DeprecationWarning, stacklevel=2)

        etype = convertExceptionType(t)
        if etype is not None:
            t = etype
        else:
            v = t, v
            t = InternalError
    return t, v