dominicsayers/foreplay

require 'net/ssh'
require 'net/ssh/shell'

module Foreplay
  class Engine
    class Remote
      autoload :Check, 'foreplay/engine/remote/check'
      autoload :Step, 'foreplay/engine/remote/step'

      include Foreplay
      attr_reader :server, :steps, :instructions

      def initialize(s, st, i)
        @server = s
        @steps = st
        @instructions = i

        @options = nil
      end

      def deploy
        output = ''

        log "Connecting to #{host} on port #{port}", host: host

        # SSH connection
        session = start_session(host, user, options)

        log "Successfully connected to #{host} on port #{port}", host: host

        session.shell do |sh|
          steps.each { |step| output += Foreplay::Engine::Remote::Step.new(host, sh, step, instructions).execute }
        end

        session.close
        output
      end

      # Deployment check: just say what we would have done
      def check
        Foreplay::Engine::Remote::Check.new(host, steps, instructions).perform
      end

      def user
        @user = instructions['user']
      end

      def host
        @host ||= host_port[0]
      end

      def port
        @port ||= (host_port[1] || 22)
      end

      def host_port
        @host_port ||= server.split(':') # Parse host + port
      end

      def options
        return @options if @options

        @options = { verbose: :warn, port: port }
        password = instructions['password']

        if password.blank?
          @options[:key_data] = [private_key]
        else
          @options[:password] = password
        end

        @options
      end

      def private_key
        pk = instructions['private_key']
        pk.blank? ? private_key_from_file : pk
      end

      def private_key_from_file
        keyfile = instructions['keyfile']
        keyfile.sub! '~', ENV['HOME'] || '/' unless keyfile.blank? # Remote shell won't expand this for us

        if keyfile.blank?
          terminate(
            'No authentication methods supplied. '\
            'You must supply a private key, key file or password in the configuration file'
          )
        end

        # Get the key from the key file
        log "Using private key from #{keyfile}"
        File.read keyfile
      end

      def start_session(host, user, options)
        Net::SSH.start(host, user, options)
      rescue SocketError => e
        terminate "There was a problem starting an ssh session on #{host}:\n#{e.message}"
      end
    end
  end
end