# frozen_string_literal: true

# Copyright (C) 2018-2020 MongoDB Inc.
#
# 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.

module Mongo
  module Operation
    # Shared behavior of operations that require their documents to each have an id.
    #
    # @since 2.5.2
    # @api private
    module Idable
      def documents
        @documents ||= ensure_ids(super)
      end

      private

      # The option for a custom id generator.
      #
      # @since 2.2.0
      ID_GENERATOR = :id_generator

      # Get the id generator.
      #
      # @example Get the id generator.
      #   idable.id_generator
      #
      # @return [ IdGenerator ] The default or custom id generator.
      #
      # @since 2.2.0
      def id_generator
        @id_generator ||= spec[ID_GENERATOR] || Operation::ObjectIdGenerator.new
      end

      def id(doc)
        doc.respond_to?(:id) ? doc.id : (doc['_id'] || doc[:_id])
      end

      def has_id?(doc)
        !!id(doc)
      end

      def ensure_ids(documents)
        @ids = []
        documents.collect do |doc|
          doc_with_id = has_id?(doc) ? doc : doc.merge(_id: id_generator.generate)
          @ids << id(doc_with_id)
          doc_with_id
        end
      end
    end
  end
end
