# vim: tabstop=4 shiftwidth=4 softtabstop=4

# Copyright 2011 Citrix Systems.
# 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.


import webob.dec
import webob.exc

from quantum.api import api_common as common
from quantum.common import wsgi


class Fault(webob.exc.HTTPException):
    """Error codes for API faults"""

    _fault_names = {
            400: "malformedRequest",
            401: "unauthorized",
            420: "networkNotFound",
            421: "networkInUse",
            430: "portNotFound",
            431: "requestedStateInvalid",
            432: "portInUse",
            440: "alreadyAttached",
            470: "serviceUnavailable",
            471: "pluginFault"
    }

    def __init__(self, exception):
        """Create a Fault for the given webob.exc.exception."""
        self.wrapped_exc = exception

    @webob.dec.wsgify(RequestClass=wsgi.Request)
    def __call__(self, req):
        """Generate a WSGI response based on the exception passed to ctor."""
        # Replace the body with fault details.
        code = self.wrapped_exc.status_int
        fault_name = self._fault_names.get(code, "quantumServiceFault")
        fault_data = {
            fault_name: {
                'code': code,
                'message': self.wrapped_exc.explanation, 
                'detail': self.wrapped_exc.detail}}
        # 'code' is an attribute on the fault tag itself
        metadata = {'application/xml': {'attributes': {fault_name: 'code'}}}
        default_xmlns = common.XML_NS_V10
        serializer = wsgi.Serializer(metadata, default_xmlns)
        content_type = req.best_match_content_type()
        self.wrapped_exc.body = serializer.serialize(fault_data, content_type)
        self.wrapped_exc.content_type = content_type
        return self.wrapped_exc


class NetworkNotFound(webob.exc.HTTPClientError):
    """
    subclass of :class:`~HTTPClientError`

    This indicates that the server did not find the network specified
    in the HTTP request

    code: 420, title: Network not Found
    """
    code = 420
    title = 'Network not Found'
    explanation = ('Unable to find a network with the specified identifier.')


class NetworkInUse(webob.exc.HTTPClientError):
    """
    subclass of :class:`~HTTPClientError`

    This indicates that the server could not delete the network as there is
    at least an attachment plugged into its ports

    code: 421, title: Network In Use
    """
    code = 421
    title = 'Network in Use'
    explanation = ('Unable to remove the network: attachments still plugged.')


class PortNotFound(webob.exc.HTTPClientError):
    """
    subclass of :class:`~HTTPClientError`

    This indicates that the server did not find the port specified
    in the HTTP request for a given network

    code: 430, title: Port not Found
    """
    code = 430
    title = 'Port not Found'
    explanation = ('Unable to find a port with the specified identifier.')


class RequestedStateInvalid(webob.exc.HTTPClientError):
    """
    subclass of :class:`~HTTPClientError`

    This indicates that the server could not update the port state to
    to the request value

    code: 431, title: Requested State Invalid
    """
    code = 431
    title = 'Requested State Invalid'
    explanation = ('Unable to update port state with specified value.')


class PortInUse(webob.exc.HTTPClientError):
    """
    subclass of :class:`~HTTPClientError`

    This indicates that the server could not remove o port or attach
    a resource to it because there is an attachment plugged into the port

    code: 432, title: PortInUse
    """
    code = 432
    title = 'Port in Use'
    explanation = ('A resource is currently attached to the logical port')


class AlreadyAttached(webob.exc.HTTPClientError):
    """
    subclass of :class:`~HTTPClientError`

    This indicates that the server refused an attempt to re-attach a resource
    already attached to the network

    code: 440, title: AlreadyAttached
    """
    code = 440
    title = 'Already Attached'
    explanation = ('The resource is already attached to another port')