#!/usr/bin/env python
#
# Copyright 2016 the original author or authors.
#
# 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.
#
from lxml import etree
import structlog
from netconf.nc_rpc.rpc import Rpc
import netconf.nc_common.error as ncerror
from netconf.constants import Constants as C
from netconf.utils import elm
from netconf import NSMAP

log = structlog.get_logger()

class GetConfig(Rpc):

	def __init__(self, rpc_request, rpc_method, session):
		super(GetConfig, self).__init__(rpc_request, rpc_method, session)
		self._validate_parameters()

	def execute(self):
		log.info('get-config-request', session=self.session.session_id)
		if self.rpc_response.is_error:
			return self.rpc_response

	def _validate_parameters(self):
		log.info('validate-parameters', session=self.session.session_id)

		self.params = self.rpc_method.getchildren()
		paramslen = len(self.params)
		# Verify that the source parameter is present
		if paramslen > 2:
			# TODO: need to specify all elements not known
			self.rpc_response.is_error = True
			self.rpc_response.node = ncerror.BadMsg(self.rpc_request)
			return

		self.source_param = self.rpc_method.find(C.NC_SOURCE, namespaces=NSMAP)
		if self.source_param is None:
			self.rpc_response.is_error = True
			self.rpc_response.node = ncerror.MissingElement(
				self.rpc_request, elm(C.NC_SOURCE))
			return

		self.filter_param = None
		if paramslen == 2:
			self.filter_param = self.rpc_method.find(C.NC_FILTER,
												  namespaces=NSMAP)
			if self.filter_param is None:
				unknown_elm = self.params[0] if self.params[0] != \
												self.source_param else \
												self.params[1]
				self.rpc_response.is_error = True
				self.rpc_response.node = ncerror.UnknownElement(
					self.rpc_request, unknown_elm)

		self.params = [self.source_param, self.filter_param]