text: # -*- coding: utf-8 -*-
  
  # Copyright (c) 2019 Minoru Osuka
  #
  # 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 whoosh.scoring import BM25F, MultiWeighting
  
  from cockatrice.util.loader import get_instance
  
  
  def get_weighting(class_name, **class_args):
      try:
          weighting = get_instance(class_name, **class_args)
      except Exception as ex:
          raise ex
  
      return weighting
  
  
  def get_multi_weighting(weighting_dict):
      try:
          default_weighting = BM25F
          field_weighting = {}
  
          for field_name in weighting_dict['weighting'].keys():
              class_name = weighting_dict['weighting'][field_name]['class']
              class_args = weighting_dict['weighting'][field_name]['args'] if 'args' in weighting_dict['weighting'][
                  field_name] else {}
              instance = get_instance(class_name, **class_args)
              if field_name == 'default':
                  default_weighting = instance
              else:
                  field_weighting[field_name] = instance
  
          weighting = MultiWeighting(default_weighting, **field_weighting)
      except Exception as ex:
          raise ex
  
      return weighting
  