class AwsElb

def fetch_from_api
  backend = BackendFactory.create(inspec_runner)
  begin
    lbs = backend.describe_load_balancers(load_balancer_names: [elb_name]).load_balancer_descriptions
    @exists = true
    # Load balancer names are uniq; we will either have 0 or 1 result
    unpack_describe_elbs_response(lbs.first)
  rescue Aws::ElasticLoadBalancing::Errors::LoadBalancerNotFound
    @exists = false
    populate_as_missing
  end
end

def populate_as_missing
  @availability_zones = []
  @external_ports = []
  @instance_ids = []
  @internal_ports = []
  @security_group_ids = []
  @subnet_ids = []
end

def to_s
  "AWS ELB #{elb_name}"
end

def unpack_describe_elbs_response(lb_struct)
  @availability_zones = lb_struct.availability_zones
  @dns_name = lb_struct.dns_name
  @external_ports = lb_struct.listener_descriptions.map { |ld| ld.listener.load_balancer_port }
  @instance_ids = lb_struct.instances.map(&:instance_id)
  @internal_ports = lb_struct.listener_descriptions.map { |ld| ld.listener.instance_port }
  @elb_name = lb_struct.load_balancer_name
  @security_group_ids = lb_struct.security_groups
  @subnet_ids = lb_struct.subnets
  @vpc_id = lb_struct.vpc_id
end

def validate_params(raw_params)
  validated_params = check_resource_param_names(
    raw_params: raw_params,
    allowed_params: [:elb_name],
    allowed_scalar_name: :elb_name,
    allowed_scalar_type: String,
  )
  if validated_params.empty?
    raise ArgumentError, 'You must provide a elb_name to aws_elb.'
  end
  validated_params
end