module BBC
  module Cosmos
    module Config
      class AWS
        def initialize(ec2)
          @ec2 = ec2
        end

        def tags
          instance.tags
        end

        def region
          ::AWS.config.region
        end

        def instance_id
          BBC::Cosmos.production? ? aws_instance_id : "instance_id"
        end

        private

        def instance
          BBC::Cosmos.production? ? aws_instance : dummy_instance
        end

        def dummy_instance
          Struct.new(:tags).new({
            "aws:cloudformation:stack-name" => "stack_name",
            "Component" => "component_name"
          })
        end

        def aws_instance
          @instance ||= @ec2.regions[region].instances[instance_id]
        end

        def aws_instance_id
          `curl http://169.254.169.254/latest/meta-data/instance-id`
        end
      end
    end
  end
end