require 'aws-sdk'

# Context
module Contexto
  # ECS class
  class Contextualize
    attr_reader :display, :cluster, :service

    def initialize(params = {})
      @cluster = params.fetch(:cluster) if params[:cluster]
      @service = params.fetch(:service) if params[:service]
      @container = params.fetch(:container) if params[:container]
      @rake = params.fetch(:rake) if params[:rake]
      @console = params.fetch(:console)
      @display = Contexto::Display.new
    end

    def run
      if (@console || @rake)
        task = describe_tasks
        ec2_instance_id = describe_container_instance(task[:container_instance_arn])
        @ssh = Contexto::SSH.new(describe_instances(ec2_instance_id), @cluster, @service, @container)
        if @console
          @ssh.console
        elsif @rake
          @ssh.rake(@rake)
        end
        return
      end
      if !@cluster
        clusters
        return
      end
      cluster
      puts "\n"
      if !@service
        services
      end
      if @service
        puts "\n"
        service
        puts "\n"
        tasks
      end
    end

    private

    def clusters
      title = "Clusters"
      headings = %w(Name)
      clusters = list_clusters
      rows = []
      clusters.each do |cluster|
        rows << [cluster.split('/')[-1]]
      end
      @display.create_display(title, headings, rows)
    end

    def cluster
      title = "Cluster #{@cluster}"
      headings = %w(Name Status Instances Services RunningTasks PendingTasks)
      cluster = describe_clusters
      rows = []
      rows << [cluster[:cluster_name], cluster[:status], cluster[:registered_container_instances_count], cluster[:active_services_count], cluster[:running_tasks_count], cluster[:pending_tasks_count]]
      @display.create_display(title, headings, rows)
    end

    def services
      title = "Services"
      headings = %w(Name)
      services = list_services
      rows = []
      services.each do |service|
        rows << [service.split('/')[-1]]
      end
      @display.create_display(title, headings, rows)
    end

    def service
      title = "Service #{@service}"
      headings = %w(Name Status Desired Running Pending)
      service = describe_services
      rows = []
      rows << [service[:service_name], service[:status], service[:desired_count], service[:running_count], service[:pending_count]]
      @display.create_display(title, headings, rows)
    rescue Aws::ECS::Errors::ServiceNotFoundException
      puts 'Service not found'
    end

    def tasks
      task = describe_tasks
      containers = task[:containers]
      ec2_instance_id = describe_container_instance(task[:container_instance_arn])
      title = 'Containers'
      headings = %w(Container Status IP)
      rows = []
      containers.each do |container|
        rows << [container[:name], container[:last_status], describe_instances(ec2_instance_id)]
      end
      @display.create_display(title, headings, rows)
    end

    def list_clusters
      resp = ecs_client.list_clusters
      resp.cluster_arns
    end

    def describe_clusters
      resp = ecs_client.describe_clusters(
        clusters: [
          @cluster
        ]
      )
      resp.clusters[0].to_h
    end

    def list_services
      resp = ecs_client.list_services(
        cluster: @cluster
      )
      resp.service_arns
    end

    def describe_services
      resp = ecs_client.describe_services(
        cluster: @cluster,
        services: [
          @service
        ]
      )
      resp.services[0].to_h
    end

    def describe_tasks
      resp = ecs_client.describe_tasks(
        cluster: @cluster,
        tasks: [task_arn]
      )
      resp.tasks[0].to_h
    end

    def task_arn
      resp = ecs_client.list_tasks(
        cluster: @cluster,
        service_name: @service
      )
      resp.task_arns[0]
    end

    def describe_container_instance(container_instance_arn)
      resp = ecs_client.describe_container_instances(
        cluster: @cluster,
        container_instances: [
          container_instance_arn
        ]
      )
      resp.container_instances[0].ec2_instance_id
    end

    def describe_instances(ec2_instance_id)
      resp = ec2_client.describe_instances(
        instance_ids: [ec2_instance_id]
      )
      resp.reservations[0].instances[0].private_ip_address
    end

    def region_name
      ENV['AWS_REGION'] || 'us-east-1'
    end

    def ecs_client
      Aws::ECS::Client.new(region: region_name.to_s)
    end

    def ec2_client
      Aws::EC2::Client.new(region: region_name.to_s)
    end
  end
end