class WaitForClusterCreationWorker
  include Sidekiq::Worker
  include DedicatedSidekiqQueue

  INITIAL_INTERVAL = 2.minutes
  EAGER_INTERVAL = 10.seconds
  TIMEOUT = 20.minutes

  def perform(cluster_id)
    cluster = Gcp::Cluster.find_by_id(cluster_id)

    unless cluster
      return Rails.logger.error "Cluster object is not found; #{cluster_id}"
    end

    api_client = 
      GoogleApi::CloudPlatform::Client.new(cluster.gcp_token, nil)

    operation = api_client.projects_zones_operations(
      cluster.gcp_project_id,
      cluster.cluster_zone,
      cluster.gcp_operation_id)

    if operation.is_a?(StandardError)
      return cluster.errored!("Failed to request to CloudPlatform; #{operation.message}")
    end

    case operation.status
    when 'RUNNING'
      if Time.now < operation.start_time.to_time + TIMEOUT
        WaitForClusterCreationWorker.perform_in(EAGER_INTERVAL, cluster.id)
      else
        return cluster.errored!("Cluster creation time exceeds timeout; #{TIMEOUT}")
      end
    when 'DONE'
      integrate(cluster, api_client)
    else
      return cluster.errored!("Unexpected operation status; #{operation.status} #{operation.status_message}")
    end
  end

  def integrate(cluster, api_client)
    gke_cluster = api_client.projects_zones_clusters_get(
      cluster.gcp_project_id,
      cluster.cluster_zone,
      cluster.cluster_name)

    if gke_cluster.is_a?(StandardError)
      return cluster.errored!("Failed to request to CloudPlatform; #{gke_cluster.message}")
    end

    begin
      endpoint = gke_cluster.endpoint
      api_url = 'https://' + endpoint
      ca_cert = Base64.decode64(gke_cluster.master_auth.cluster_ca_certificate)
      username = gke_cluster.master_auth.username
      password = gke_cluster.master_auth.password
    rescue Exception => e
      return cluster.errored!("Can not extract the expected data; #{e}")
    end

    kubernetes_token = Ci::FetchKubernetesTokenService.new(
      api_url, ca_cert, username, password).execute

    unless kubernetes_token
      return cluster.errored!('Failed to get a default token of kubernetes')
    end

    Ci::IntegrateClusterService.new.execute(
      cluster, endpoint, ca_cert, kubernetes_token, username, password)
  end
end