##
# Copyright (c) 2006-2007 Apple 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.
##

"""
Implements drop-box functionality. A drop box is an external attachment store.
"""

__all__ = [
    "DropBoxHomeResource",
    "DropBoxCollectionResource",
    "DropBoxChildResource",
]

from twext.web2.dav.davxml import ErrorResponse
from twisted.web2 import responsecode
from twisted.web2.dav import davxml
from twisted.web2.dav.resource import DAVResource, TwistedACLInheritable

from twistedcaldav.customxml import calendarserver_namespace
from twistedcaldav.log import Logger

log = Logger()

class DropBoxHomeResource (DAVResource):
    """
    Drop box collection resource.
    """
    def resourceType(self):
        return davxml.ResourceType.dropboxhome

    def isCollection(self):
        return True

    def http_PUT(self, request):
        return responsecode.FORBIDDEN

class DropBoxCollectionResource (DAVResource):
    """
    Drop box resource.
    """
    def resourceType(self):
        return davxml.ResourceType.dropbox

    def isCollection(self):
        return True

    def writeNewACEs(self, newaces):
        """
        Write a new ACL to the resource's property store. We override this for calendar collections
        and force all the ACEs to be inheritable so that all calendar object resources within the
        calendar collection have the same privileges unless explicitly overridden. The same applies
        to drop box collections as we want all resources (attachments) to have the same privileges as
        the drop box collection.
        
        @param newaces: C{list} of L{ACE} for ACL being set.
        """
        # Add inheritable option to each ACE in the list
        edited_aces = []
        for ace in newaces:
            if TwistedACLInheritable() not in ace.children:
                children = list(ace.children)
                children.append(TwistedACLInheritable())
                edited_aces.append(davxml.ACE(*children))
            else:
                edited_aces.append(ace)
        
        # Do inherited with possibly modified set of aces
        super(DropBoxCollectionResource, self).writeNewACEs(edited_aces)

    def http_PUT(self, request):
        return ErrorResponse(
            responsecode.FORBIDDEN,
            (calendarserver_namespace, "valid-drop-box")
        )