module Terraforming
  module Resource
    class EC2
      include Terraforming::Util

      def self.tf(client = Aws::EC2::Client.new)
        self.new(client).tf
      end

      def self.tfstate(client = Aws::EC2::Client.new)
        self.new(client).tfstate
      end

      def initialize(client)
        @client = client
      end

      def tf
        apply_template(@client, "tf/ec2")
      end

      def tfstate
        resources = instances.inject({}) do |result, instance|
          attributes = {
            "ami"=> instance.image_id,
            "associate_public_ip_address"=> "true",
            "availability_zone"=> instance.placement.availability_zone,
            "ebs_block_device.#"=> instance.block_device_mappings.length.to_s,
            "ebs_optimized"=> instance.ebs_optimized.to_s,
            "ephemeral_block_device.#"=> "0",
            "id"=> instance.instance_id,
            "instance_type"=> instance.instance_type,
            "private_dns"=> instance.private_dns_name,
            "private_ip"=> instance.private_ip_address,
            "public_dns"=> instance.public_dns_name,
            "public_ip"=> instance.public_ip_address,
            "root_block_device.#"=> instance.root_device_name ? "1" : "0",
            "security_groups.#"=> instance.security_groups.length.to_s,
            "source_dest_check"=> instance.source_dest_check.to_s,
            "subnet_id"=> instance.subnet_id,
            "tenancy"=> instance.placement.tenancy
          }
          result["aws_instance.#{module_name_of(instance)}"] = {
            "type" => "aws_instance",
            "primary" => {
              "id" => instance.instance_id,
              "attributes" => attributes,
              "meta" => {
                "schema_version" => "1"
              }
            }
          }

          result
        end

        generate_tfstate(resources)
      end

      private

      def instances
        @client.describe_instances.reservations.map(&:instances).flatten
      end

      def module_name_of(instance)
        normalize_module_name(name_from_tag(instance, instance.instance_id))
      end
    end
  end
end