module Opsicle
  class FailureLog
    attr_reader :client, :stack

    def initialize(environment)
      @environment = environment
      @client = Client.new(environment)
      @stack = Opsicle::Stack.new(@client)
    end

    def execute
      puts "Getting most recent failure log..."

      fetch
    end

    def fetch
      failed_deployments = fetch_failed_deployments

      unless failed_deployments.empty?
        failed_deployment_id = failed_deployments.first.deployment_id
        failed_deployments_instances = failed_deployments.first.instance_ids

        unless failed_deployments_instances.empty?
          involved_instance_id = fetch_instance_id(failed_deployments_instances)

          target_failed_command = fetch_target_command(involved_instance_id, failed_deployment_id)
          log_url = target_failed_command.first.log_url
        
          system("open", log_url) if log_url
          puts "Unable to find a url to open." unless log_url
        else
          puts "There is at least one failed deployment, but there is no log available for that failure."
        end
      else
        puts "No failed deployments in available history."
      end
    end

    def fetch_failed_deployments
      deployments = @client.opsworks.describe_deployments(stack_id: @stack.stack_id).deployments
      deployments.select{ |deploy| deploy.status.eql? "failed" }
    end

    def fetch_instance_id(failed_deployments_instances)
      involved_instances = @client.opsworks.describe_instances(instance_ids: failed_deployments_instances).instances
      choice = select_instance(involved_instances)
      involved_instances[choice-1].instance_id
    end

    def fetch_target_command(involved_instance_id, failed_deployment_id)
      command_list = @client.opsworks.describe_commands(instance_id: involved_instance_id)[:commands]
      command_list.select{ |command| command.deployment_id == failed_deployment_id }
    end

    def select_instance(instance_list)
      if instance_list.length == 1
        choice = 1
      else
        Output.say "Choose an Opsworks instance:"
        instance_list.each_with_index do |instance, index|
          Output.say "#{index+1}) #{instance[:hostname]}"
        end
        choice = Output.ask("? ", Integer) { |q| q.in = 1..instance_list.length }
      end
      return choice
    end
  end
end