module Vcloud
  module EdgeGateway
    class EdgeGatewayConfiguration

      def initialize(local_config, remote_config, edge_gateway_interfaces)
        @local_config = local_config
        @remote_config = remote_config
        @edge_gateway_interfaces = edge_gateway_interfaces
        @config = { }
        @update_required = nil
      end

      def update_required?
        @update_required = false

        firewall_service_config = EdgeGateway::ConfigurationGenerator::FirewallService.new.generate_fog_config(@local_config[:firewall_service])
        unless firewall_service_config.nil?
          differ = EdgeGateway::FirewallConfigurationDiffer.new(firewall_service_config, @remote_config[:FirewallService])
          unless differ.diff.empty?
            @config[:FirewallService] = firewall_service_config
            @update_required = true
          end
        end

        nat_service_config = EdgeGateway::ConfigurationGenerator::NatService.new(
          @local_config[:nat_service],
          @edge_gateway_interfaces
        ).generate_fog_config

        unless nat_service_config.nil?
          differ = EdgeGateway::NatConfigurationDiffer.new(nat_service_config, @remote_config[:NatService])
          unless differ.diff.empty?
            @config[:NatService] = nat_service_config
            @update_required = true
          end
        end

        load_balancer_service_config =
          EdgeGateway::ConfigurationGenerator::LoadBalancerService.new(
            @edge_gateway_interfaces
          ).generate_fog_config(@local_config[:load_balancer_service])

        unless load_balancer_service_config.nil?
          differ = EdgeGateway::LoadBalancerConfigurationDiffer.new(
                     load_balancer_service_config,
                     @remote_config[:LoadBalancerService]
                   )
          unless differ.diff.empty?
            @config[:LoadBalancerService] = load_balancer_service_config
            @update_required = true
          end
        end

        @update_required
      end

      def config
        if @update_required.nil?
          update_required?
        end
        @config
      end

    end
  end
end