# Copyright (c) 2017 Hitachi, Ltd.
#
#    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 datetime
from http import client as http_client

from ironic_lib import metrics_utils
from oslo_utils import uuidutils
from pecan import rest
import wsme

from ironic import api
from ironic.api.controllers import base
from ironic.api.controllers import link
from ironic.api.controllers.v1 import collection
from ironic.api.controllers.v1 import notification_utils as notify
from ironic.api.controllers.v1 import types
from ironic.api.controllers.v1 import utils as api_utils
from ironic.api import expose
from ironic.api import types as atypes
from ironic.common import exception
from ironic.common.i18n import _
from ironic.common import policy
from ironic import objects

METRICS = metrics_utils.get_metrics_logger(__name__)

_DEFAULT_RETURN_FIELDS = ('uuid', 'node_uuid', 'type', 'connector_id')


class VolumeConnector(base.APIBase):
    """API representation of a volume connector.

    This class enforces type checking and value constraints, and converts
    between the internal object model and the API representation of a volume
    connector.
    """

    _node_uuid = None

    def _get_node_uuid(self):
        return self._node_uuid

    def _set_node_identifiers(self, value):
        """Set both UUID and ID of a node for VolumeConnector object

        :param value: UUID, ID of a node, or atypes.Unset
        """
        if value == atypes.Unset:
            self._node_uuid = atypes.Unset
        elif value and self._node_uuid != value:
            try:
                node = objects.Node.get(api.request.context, value)
                self._node_uuid = node.uuid
                # NOTE(smoriya): Create the node_id attribute on-the-fly
                #                to satisfy the api -> rpc object conversion.
                self.node_id = node.id
            except exception.NodeNotFound as e:
                # Change error code because 404 (NotFound) is inappropriate
                # response for a POST request to create a VolumeConnector
                e.code = http_client.BAD_REQUEST  # BadRequest
                raise

    uuid = types.uuid
    """Unique UUID for this volume connector"""

    type = atypes.wsattr(str, mandatory=True)
    """The type of volume connector"""

    connector_id = atypes.wsattr(str, mandatory=True)
    """The connector_id for this volume connector"""

    extra = {str: types.jsontype}
    """The metadata for this volume connector"""

    node_uuid = atypes.wsproperty(types.uuid, _get_node_uuid,
                                  _set_node_identifiers, mandatory=True)
    """The UUID of the node this volume connector belongs to"""

    links = atypes.wsattr([link.Link], readonly=True)
    """A list containing a self link and associated volume connector links"""

    def __init__(self, **kwargs):
        self.fields = []
        fields = list(objects.VolumeConnector.fields)
        for field in fields:
            # Skip fields we do not expose.
            if not hasattr(self, field):
                continue
            self.fields.append(field)
            setattr(self, field, kwargs.get(field, atypes.Unset))

        # NOTE(smoriya): node_id is an attribute created on-the-fly
        # by _set_node_uuid(), it needs to be present in the fields so
        # that as_dict() will contain node_id field when converting it
        # before saving it in the database.
        self.fields.append('node_id')
        # NOTE(smoriya): node_uuid is not part of objects.VolumeConnector.-
        #                fields because it's an API-only attribute
        self.fields.append('node_uuid')
        # NOTE(jtaryma): Additionally to node_uuid, node_id is handled as a
        # secondary identifier in case RPC volume connector object dictionary
        # was passed to the constructor.
        self.node_uuid = kwargs.get('node_uuid') or kwargs.get('node_id',
                                                               atypes.Unset)

    @staticmethod
    def _convert_with_links(connector, url):

        connector.links = [link.Link.make_link('self', url,
                                               'volume/connectors',
                                               connector.uuid),
                           link.Link.make_link('bookmark', url,
                                               'volume/connectors',
                                               connector.uuid,
                                               bookmark=True)
                           ]
        return connector

    @classmethod
    def convert_with_links(cls, rpc_connector, fields=None, sanitize=True):
        connector = VolumeConnector(**rpc_connector.as_dict())

        if fields is not None:
            api_utils.check_for_invalid_fields(fields, connector.as_dict())

        connector = cls._convert_with_links(connector,
                                            api.request.public_url)

        if not sanitize:
            return connector

        connector.sanitize(fields)

        return connector

    def sanitize(self, fields=None):
        """Removes sensitive and unrequested data.

        Will only keep the fields specified in the ``fields`` parameter.

        :param fields:
            list of fields to preserve, or ``None`` to preserve them all
        :type fields: list of str
        """

        if fields is not None:
            self.unset_fields_except(fields)

        # never expose the node_id attribute
        self.node_id = atypes.Unset

    @classmethod
    def sample(cls, expand=True):
        time = datetime.datetime(2000, 1, 1, 12, 0, 0)
        sample = cls(uuid='86cfd480-0842-4abb-8386-e46149beb82f',
                     type='iqn',
                     connector_id='iqn.2010-10.org.openstack:51332b70524',
                     extra={'foo': 'bar'},
                     created_at=time,
                     updated_at=time)
        sample._node_uuid = '7ae81bb3-dec3-4289-8d6c-da80bd8001ae'
        fields = None if expand else _DEFAULT_RETURN_FIELDS
        return cls._convert_with_links(sample, 'http://localhost:6385',
                                       fields=fields)


class VolumeConnectorPatchType(types.JsonPatchType):

    _api_base = VolumeConnector


class VolumeConnectorCollection(collection.Collection):
    """API representation of a collection of volume connectors."""

    connectors = [VolumeConnector]
    """A list containing volume connector objects"""

    def __init__(self, **kwargs):
        self._type = 'connectors'

    @staticmethod
    def convert_with_links(rpc_connectors, limit, url=None, fields=None,
                           detail=None, **kwargs):
        collection = VolumeConnectorCollection()
        collection.connectors = [
            VolumeConnector.convert_with_links(p, fields=fields,
                                               sanitize=False)
            for p in rpc_connectors]
        if detail:
            kwargs['detail'] = detail
        collection.next = collection.get_next(limit, url=url, fields=fields,
                                              **kwargs)
        for connector in collection.connectors:
            connector.sanitize(fields)
        return collection

    @classmethod
    def sample(cls):
        sample = cls()
        sample.connectors = [VolumeConnector.sample(expand=False)]
        return sample


class VolumeConnectorsController(rest.RestController):
    """REST controller for VolumeConnectors."""

    invalid_sort_key_list = ['extra']

    def __init__(self, node_ident=None):
        super(VolumeConnectorsController, self).__init__()
        self.parent_node_ident = node_ident

    def _get_volume_connectors_collection(self, node_ident, marker, limit,
                                          sort_key, sort_dir,
                                          resource_url=None,
                                          fields=None, detail=None):
        limit = api_utils.validate_limit(limit)
        sort_dir = api_utils.validate_sort_dir(sort_dir)

        marker_obj = None
        if marker:
            marker_obj = objects.VolumeConnector.get_by_uuid(
                api.request.context, marker)

        if sort_key in self.invalid_sort_key_list:
            raise exception.InvalidParameterValue(
                _("The sort_key value %(key)s is an invalid field for "
                  "sorting") % {'key': sort_key})

        node_ident = self.parent_node_ident or node_ident

        if node_ident:
            # FIXME(comstud): Since all we need is the node ID, we can
            #                 make this more efficient by only querying
            #                 for that column. This will get cleaned up
            #                 as we move to the object interface.
            node = api_utils.get_rpc_node(node_ident)
            connectors = objects.VolumeConnector.list_by_node_id(
                api.request.context, node.id, limit, marker_obj,
                sort_key=sort_key, sort_dir=sort_dir)
        else:
            connectors = objects.VolumeConnector.list(api.request.context,
                                                      limit,
                                                      marker_obj,
                                                      sort_key=sort_key,
                                                      sort_dir=sort_dir)
        return VolumeConnectorCollection.convert_with_links(connectors, limit,
                                                            url=resource_url,
                                                            fields=fields,
                                                            sort_key=sort_key,
                                                            sort_dir=sort_dir,
                                                            detail=detail)

    @METRICS.timer('VolumeConnectorsController.get_all')
    @expose.expose(VolumeConnectorCollection, types.uuid_or_name, types.uuid,
                   int, str, str, types.listtype,
                   types.boolean)
    def get_all(self, node=None, marker=None, limit=None, sort_key='id',
                sort_dir='asc', fields=None, detail=None):
        """Retrieve a list of volume connectors.

        :param node: UUID or name of a node, to get only volume connectors
                     for that node.
        :param marker: pagination marker for large data sets.
        :param limit: maximum number of resources to return in a single result.
                      This value cannot be larger than the value of max_limit
                      in the [api] section of the ironic configuration, or only
                      max_limit resources will be returned.
        :param sort_key: column to sort results by. Default: id.
        :param sort_dir: direction to sort. "asc" or "desc". Default: "asc".
        :param fields: Optional, a list with a specified set of fields
                       of the resource to be returned.
        :param detail: Optional, whether to retrieve with detail.

        :returns: a list of volume connectors, or an empty list if no volume
                  connector is found.

        :raises: InvalidParameterValue if sort_key does not exist
        :raises: InvalidParameterValue if sort key is invalid for sorting.
        :raises: InvalidParameterValue if both fields and detail are specified.
        """
        cdict = api.request.context.to_policy_values()
        policy.authorize('baremetal:volume:get', cdict, cdict)

        if fields is None and not detail:
            fields = _DEFAULT_RETURN_FIELDS

        if fields and detail:
            raise exception.InvalidParameterValue(
                _("Can't fetch a subset of fields with 'detail' set"))

        resource_url = 'volume/connectors'
        return self._get_volume_connectors_collection(
            node, marker, limit, sort_key, sort_dir, resource_url=resource_url,
            fields=fields, detail=detail)

    @METRICS.timer('VolumeConnectorsController.get_one')
    @expose.expose(VolumeConnector, types.uuid, types.listtype)
    def get_one(self, connector_uuid, fields=None):
        """Retrieve information about the given volume connector.

        :param connector_uuid: UUID of a volume connector.
        :param fields: Optional, a list with a specified set of fields
            of the resource to be returned.

        :returns: API-serializable volume connector object.

        :raises: OperationNotPermitted if accessed with specifying a parent
                 node.
        :raises: VolumeConnectorNotFound if no volume connector exists with
                 the specified UUID.
        """
        cdict = api.request.context.to_policy_values()
        policy.authorize('baremetal:volume:get', cdict, cdict)

        if self.parent_node_ident:
            raise exception.OperationNotPermitted()

        rpc_connector = objects.VolumeConnector.get_by_uuid(
            api.request.context, connector_uuid)
        return VolumeConnector.convert_with_links(rpc_connector, fields=fields)

    @METRICS.timer('VolumeConnectorsController.post')
    @expose.expose(VolumeConnector, body=VolumeConnector,
                   status_code=http_client.CREATED)
    def post(self, connector):
        """Create a new volume connector.

        :param connector: a volume connector within the request body.

        :returns: API-serializable volume connector object.

        :raises: OperationNotPermitted if accessed with specifying a parent
                 node.
        :raises: VolumeConnectorTypeAndIdAlreadyExists if a volume
                 connector already exists with the same type and connector_id
        :raises: VolumeConnectorAlreadyExists if a volume connector with the
                 same UUID already exists
        """
        context = api.request.context
        cdict = context.to_policy_values()
        policy.authorize('baremetal:volume:create', cdict, cdict)

        if self.parent_node_ident:
            raise exception.OperationNotPermitted()

        connector_dict = connector.as_dict()
        # NOTE(hshiina): UUID is mandatory for notification payload
        if not connector_dict.get('uuid'):
            connector_dict['uuid'] = uuidutils.generate_uuid()

        new_connector = objects.VolumeConnector(context, **connector_dict)

        notify.emit_start_notification(context, new_connector, 'create',
                                       node_uuid=connector.node_uuid)
        with notify.handle_error_notification(context, new_connector,
                                              'create',
                                              node_uuid=connector.node_uuid):
            new_connector.create()
        notify.emit_end_notification(context, new_connector, 'create',
                                     node_uuid=connector.node_uuid)
        # Set the HTTP Location Header
        api.response.location = link.build_url('volume/connectors',
                                               new_connector.uuid)
        return VolumeConnector.convert_with_links(new_connector)

    @METRICS.timer('VolumeConnectorsController.patch')
    @wsme.validate(types.uuid, [VolumeConnectorPatchType])
    @expose.expose(VolumeConnector, types.uuid,
                   body=[VolumeConnectorPatchType])
    def patch(self, connector_uuid, patch):
        """Update an existing volume connector.

        :param connector_uuid: UUID of a volume connector.
        :param patch: a json PATCH document to apply to this volume connector.

        :returns: API-serializable volume connector object.

        :raises: OperationNotPermitted if accessed with specifying a
                 parent node.
        :raises: PatchError if a given patch can not be applied.
        :raises: VolumeConnectorNotFound if no volume connector exists with
                 the specified UUID.
        :raises: InvalidParameterValue if the volume connector's UUID is being
                 changed
        :raises: NodeLocked if node is locked by another conductor
        :raises: NodeNotFound if the node associated with the connector does
                 not exist
        :raises: VolumeConnectorTypeAndIdAlreadyExists if another connector
                 already exists with the same values for type and connector_id
                 fields
        :raises: InvalidUUID if invalid node UUID is passed in the patch.
        :raises: InvalidStateRequested If a node associated with the
                 volume connector is not powered off.
        """
        context = api.request.context
        cdict = context.to_policy_values()
        policy.authorize('baremetal:volume:update', cdict, cdict)

        if self.parent_node_ident:
            raise exception.OperationNotPermitted()

        values = api_utils.get_patch_values(patch, '/node_uuid')
        for value in values:
            if not uuidutils.is_uuid_like(value):
                message = _("Expected a UUID for node_uuid, but received "
                            "%(uuid)s.") % {'uuid': str(value)}
                raise exception.InvalidUUID(message=message)

        rpc_connector = objects.VolumeConnector.get_by_uuid(context,
                                                            connector_uuid)
        connector_dict = rpc_connector.as_dict()
        # NOTE(smoriya):
        # 1) Remove node_id because it's an internal value and
        #    not present in the API object
        # 2) Add node_uuid
        connector_dict['node_uuid'] = connector_dict.pop('node_id', None)
        connector = VolumeConnector(
            **api_utils.apply_jsonpatch(connector_dict, patch))

        # Update only the fields that have changed.
        for field in objects.VolumeConnector.fields:
            try:
                patch_val = getattr(connector, field)
            except AttributeError:
                # Ignore fields that aren't exposed in the API
                continue
            if patch_val == atypes.Unset:
                patch_val = None
            if rpc_connector[field] != patch_val:
                rpc_connector[field] = patch_val

        rpc_node = objects.Node.get_by_id(context,
                                          rpc_connector.node_id)
        notify.emit_start_notification(context, rpc_connector, 'update',
                                       node_uuid=rpc_node.uuid)
        with notify.handle_error_notification(context, rpc_connector, 'update',
                                              node_uuid=rpc_node.uuid):
            topic = api.request.rpcapi.get_topic_for(rpc_node)
            new_connector = api.request.rpcapi.update_volume_connector(
                context, rpc_connector, topic)

        api_connector = VolumeConnector.convert_with_links(new_connector)
        notify.emit_end_notification(context, new_connector, 'update',
                                     node_uuid=rpc_node.uuid)
        return api_connector

    @METRICS.timer('VolumeConnectorsController.delete')
    @expose.expose(None, types.uuid, status_code=http_client.NO_CONTENT)
    def delete(self, connector_uuid):
        """Delete a volume connector.

        :param connector_uuid: UUID of a volume connector.

        :raises: OperationNotPermitted if accessed with specifying a
                 parent node.
        :raises: NodeLocked if node is locked by another conductor
        :raises: NodeNotFound if the node associated with the connector does
                 not exist
        :raises: VolumeConnectorNotFound if the volume connector cannot be
                 found
        :raises: InvalidStateRequested If a node associated with the
                 volume connector is not powered off.
        """
        context = api.request.context
        cdict = context.to_policy_values()
        policy.authorize('baremetal:volume:delete', cdict, cdict)

        if self.parent_node_ident:
            raise exception.OperationNotPermitted()

        rpc_connector = objects.VolumeConnector.get_by_uuid(context,
                                                            connector_uuid)
        rpc_node = objects.Node.get_by_id(context, rpc_connector.node_id)
        notify.emit_start_notification(context, rpc_connector, 'delete',
                                       node_uuid=rpc_node.uuid)
        with notify.handle_error_notification(context, rpc_connector,
                                              'delete',
                                              node_uuid=rpc_node.uuid):
            topic = api.request.rpcapi.get_topic_for(rpc_node)
            api.request.rpcapi.destroy_volume_connector(context,
                                                        rpc_connector, topic)
        notify.emit_end_notification(context, rpc_connector, 'delete',
                                     node_uuid=rpc_node.uuid)
