# GOV.UK Mini Environment Admin
# Copyright © 2018  Christopher Baines <mail@cbaines.net>
#
# This file is part of the GOV.UK Mini Environment Admin.
#
# The GOV.UK Mini Environment Admin is free software: you can
# redistribute it and/or modify it under the terms of the GNU Affero
# General Public License as published by the Free Software Foundation,
# either version 3 of the License, or (at your option) any later
# version.
#
# The GOV.UK Mini Environment Admin is distributed in the hope that it
# will be useful, but WITHOUT ANY WARRANTY; without even the implied
# warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
# See the GNU Affero General Public License for more details.
#
# You should have received a copy of the GNU Affero General Public
# License along with the GOV.UK Mini Environment Admin.  If not, see
# <http://www.gnu.org/licenses/>.

# == Schema Information
#
# Table name: terraform_aws_backends
#
#  id                    :integer          not null, primary key
#  label                 :string
#  aws_region            :string
#  aws_access_key_id     :string
#  aws_secret_access_key :string
#  created_at            :datetime         not null
#  updated_at            :datetime         not null
#  domain                :string
#

require 'ruby_terraform'

class Backends::TerraformAws < ApplicationRecord
  has_many :mini_environments, as: :backend

  self.table_name = 'terraform_aws_backends'

  def self.label
    'Amazon Web Services'
  end

  def type_and_id
    "#{self.class.name}=#{id}"
  end

  def build(mini_environment)
    slug = mini_environment.name.parameterize

    GovukGuix::BuildJob.enqueue(
      mini_environment.id,
      %w(whitehall government-frontend),
      type: 'container-start-script',
      app_domain: "#{slug}.#{domain}",
      web_domain: "www.#{slug}.#{domain}",
      use_https: 'certbot'
    )
  end

  def start(mini_environment)
    logger.info "Setting up #{mini_environment.name}"

    within_terraform_working_directory(mini_environment) do
      RubyTerraform.apply(
        vars: terraform_variables(mini_environment),
        auto_approve: true
      )
    end
  end

  def destroy(mini_environment)
    within_terraform_working_directory(mini_environment) do
      RubyTerraform.destroy(
        vars: terraform_variables(mini_environment),
        force: true
      )
    end
  end

  def within_terraform_working_directory(mini_environment, &block)
    TerraformWorkingDirectory.new(
      "mini_environment/#{mini_environment.id}",
      'terraform/aws'
    ).within_working_directory(&block)
  end

  def signon_url(mini_environment)
    "https://signon.#{mini_environment.name.parameterize}.#{domain}"
  end

  def terraform_variables(mini_environment)
    {
      aws_access_key: aws_access_key_id,
      aws_secret_key: aws_secret_access_key,
      aws_region: aws_region,
      slug: mini_environment.name.parameterize,
      ssh_public_key: ssh_public_key,
      start_command: mini_environment.backend_data['build_output']
    }
  end

  def ssh_public_key
    File.open("#{ENV['HOME']}/.ssh/id_rsa.pub", &:readline)
  end
end