# frozen_string_literal: true

# Copyright (C) 2015-2020 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
    class ParallelScan
      # Defines custom behavior of results in a parallel scan.
      #
      # @since 2.0.0
      # @api semiprivate
      class Result < Operation::Result
        # The name of the cursors field in the result.
        #
        # @since 2.0.0
        # @api private
        CURSORS = 'cursors'

        # Get all the cursor ids from the result.
        #
        # @example Get the cursor ids.
        #   result.cursor_ids
        #
        # @return [ Array<Integer> ] The cursor ids.
        #
        # @since 2.0.0
        # @api private
        def cursor_ids
          documents.map { |doc| doc[CURSOR][CURSOR_ID] }
        end

        # Get the documents from parallel scan.
        #
        # @example Get the documents.
        #   result.documents
        #
        # @return [ Array<BSON::Document> ] The documents.
        #
        # @since 2.0.0
        # @api public
        def documents
          reply.documents[0][CURSORS]
        end

        private

        def first
          @first ||= reply.documents[0] || {}
        end
      end
    end
  end
end
