require "resource_support/aws/aws_singular_resource_mixin"
require "resource_support/aws/aws_backend_base"
require "aws-sdk-iam"

class AwsIamRootUser < Inspec.resource(1)
  name "aws_iam_root_user"
  desc "Verifies settings for AWS root account"
  example <<~EXAMPLE
    describe aws_iam_root_user do
      it { should have_access_key }
    end
  EXAMPLE
  supports platform: "aws"

  # TODO: rewrite to avoid direct injection, match other resources, use AwsSingularResourceMixin
  def initialize(conn = nil)
    @client = conn ? conn.iam_client : inspec_runner.backend.aws_client(Aws::IAM::Client)
  end

  # TODO: DRY up, see https://github.com/chef/inspec/issues/2633
  # Copied from resource_support/aws/aws_resource_mixin.rb
  def catch_aws_errors
    yield
  rescue Aws::Errors::MissingCredentialsError
    # The AWS error here is unhelpful:
    # "unable to sign request without credentials set"
    Inspec::Log.error "It appears that you have not set your AWS credentials.  You may set them using environment variables, or using the 'aws://region/aws_credentials_profile' target.  See https://www.inspec.io/docs/reference/platforms for details."
    fail_resource("No AWS credentials available")
  rescue Aws::Errors::ServiceError => e
    fail_resource e.message
  end

  # TODO: DRY up, see https://github.com/chef/inspec/issues/2633
  # Copied from resource_support/aws/aws_singular_resource_mixin.rb
  def inspec_runner
    # When running under inspec-cli, we have an 'inspec' method that
    # returns the runner. When running under unit tests, we don't
    # have that, but we still have to call this to pass something
    # (nil is OK) to the backend.
    # TODO: remove with https://github.com/chef/inspec-aws/issues/216
    # TODO: remove after rewrite to include AwsSingularResource
    inspec if respond_to?(:inspec)
  end

  def has_access_key?
    summary_account["AccountAccessKeysPresent"] == 1
  end

  def has_mfa_enabled?
    summary_account["AccountMFAEnabled"] == 1
  end

  # if the root account has a Virtual MFA device then it will have a special
  # serial number ending in 'root-account-mfa-device'
  def has_virtual_mfa_enabled?
    mfa_device_pattern = %r{arn:aws:iam::\d{12}:mfa\/root-account-mfa-device}

    virtual_mfa_devices.any? { |d| mfa_device_pattern =~ d["serial_number"] }
  end

  def has_hardware_mfa_enabled?
    has_mfa_enabled? && !has_virtual_mfa_enabled?
  end

  def to_s
    "AWS Root-User"
  end

  private

  def summary_account
    catch_aws_errors do
      @summary_account ||= @client.get_account_summary.summary_map
    end
  end

  def virtual_mfa_devices
    catch_aws_errors do
      @__virtual_devices ||= @client.list_virtual_mfa_devices.virtual_mfa_devices
    end
  end
end