module Publisher
  class Ssh
    attr_accessor :remote_user
    attr_accessor :remote_host
    attr_accessor :ssh_key_file

    def remote_execute(command)
      Helper.validates_presence_of remote_user,  'Remote User not set'
      Helper.validates_presence_of remote_host,  'Remote Host not set'
      Helper.validates_presence_of ssh_key_file, 'SSH keyfile not set'
      Helper.validates_presence_of command,      'No valid remote command given'

      result          = ''
      # joined_filename = File.join(File.dirname($exec_file_path), ssh_key_file)
      # ssh_key_file    = joined_filename

      unless File.file? ssh_key_file
        $log.writer.error "Can not find SSH keyfile #{ssh_key_file}"
        exit 1
      end

      Net::SSH.start(remote_host, remote_user, \
                     auth_methods: ['publickey'], \
                     forward_agent: true, \
                     keys: ssh_key_file, \
                     timeout: 30) do |session|
        session.open_channel do |channel|
          channel.exec command do |ch, success|
            unless success
              $log.writer.error "could not execute remote command: '#{command}'"
              exit 1
            end

            ch.on_data do |_ch, data| # STDOUT of command
              if data
                $log.writer.debug data.strip
                result << data
              else
                $log.writer.info 'Warning: Maybe successfully executed but no output found'
              end
            end

            ch.on_extended_data do |_ch, type, data| # STDERR of command
              $log.writer.error 'could not execute command'
              $log.writer.error data
              $log.writer.error type
              exit 1
            end

            ch.on_close do |_ch|
              # result << "all done, closing!"
            end
          end
        end
      end
      result
    end

    def remove_old_releases(path, num_of_releases_to_keep, release_name_shema)
      releases = remote_execute("ls #{path}").split("\n").select { |dir| dir =~ release_name_shema }.sort
      num_to_remove = releases.size - num_of_releases_to_keep
      releases_to_delete = releases.take(num_to_remove < 0 ? 0 : num_to_remove)
      releases_to_delete.each do |dir|
        $log.writer.debug "removing #{path}/#{dir}"
        remote_execute("rm -rf #{path}/#{dir}")
      end
    end
  end
end