# Licensed to Elasticsearch B.V. under one or more contributor
# license agreements. See the NOTICE file distributed with
# this work for additional information regarding copyright
# ownership. Elasticsearch B.V. licenses this file to you 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.

# frozen_string_literal: true

module ElasticAPM
  module Transport
    # @api private
    class UserAgent
      def initialize(config, version: VERSION)
        @version = version
        @built = build(config)
      end

      def to_s
        @built
      end

      private

      def build(config)
        service = Metadata::ServiceInfo.new(config)

        [
          "elastic-apm-ruby/#{@version}",
          formatted_service_info(service)
        ].compact.join(' ')
      end

      def formatted_service_info(service)
        if service.name
          "(#{[
                service.name,
                service.version
               ].compact.join(' ')
             })"
        end
      end
    end
  end
end