#!/usr/bin/env ruby

require 'net/ftptls'
require 'optparse'
require 'irb'
require 'irb/workspace'

module IRB
  def IRB.session(name, object)
    IRB.setup(name)
    irb = Irb.new(IRB::WorkSpace.new(object))
    @CONF[:MAIN_CONTEXT] = irb.context

    trap("SIGINT") do
      irb.signal_handle
    end
    catch(:IRB_EXIT) do
      irb.eval_input
    end
  end
end

class SecureFTP
  def initialize(host, port = 21, user = nil, pass = nil)
    @session = Net::FTPTLS.new
    @session.passive = true
    @session.connect(host, port)
    @session.login(user, pass) if user && pass
  end
  def close
    @session.close
  end
  def method_missing(meth, *args, &block)
    if @session.respond_to?(meth)
      @session.send(meth, *args, &block)
    else
      @session.sendcmd(site_cmd(meth, *args))
    end
  end
  def site_cmd(meth, *args)
    cmd = "site #{meth}"
    cmd << " #{args.join(' ')}" unless args.empty?
    cmd
  end
end

options = { :port => 21 }
OptionParser.new do |opt|
  opt.banner = "Usage: $0 [hostname] [options]"
  opt.on('-u', '--user', String, 'FTP Username') { |v| options[:user] = v }
  opt.on('-p', '--pass', String, 'FTP Password') { |v| options[:pass] = v }
  opt.on('-P', '--port', Integer, 'FTP Port') { |v| options[:port] = v }
  opt.parse!(ARGV)
end

begin
  ftp = SecureFTP.new(ARGV[0], options[:port], options[:username], options[:password])
  IRB.session(ftp.class.name, ftp)
ensure
  ftp.close
end