em-irc-client.rb

#!/usr/bin/env ruby
# -*- coding: utf-8 -*-

require 'ircp'
require 'pit'
require 'eventmachine'

class IrcClient < EM::Connection
  def initialize(options)
    @nick = options[:nick]
    @user = options[:user] || @nick
    @real = options[:real] || @nick
    @pass = options[:pass]
  end

  def send(*args)
    msg = Ircp::Message.new(*args)
    puts msg.to_s
    send_data msg.to_irc
  end

  def post_init
    send 'PASS', @pass if @pass
    send 'NICK', @nick
    send 'USER', @user, '*', '*', @real
  end

  def unbind
  end

  def receive_data(data)
    msg = Ircp.parse data
    method = "on_#{msg.command.to_s.downcase}"
    __send__ method, msg if respond_to? method
  end

  def on_ping(msg)
    send 'PONG'
  end

  def on_privmsg(msg)
    puts msg.to_s
  end

  def on_notice(msg)
    puts msg.to_s
  end
end

options = {
    host: '127.0.0.1',
    port: 6667,
    nick: 'shunirr',
}
EM.run do
  Signal.trap("INT")  { EM.stop }
  Signal.trap("TERM") { EM.stop }
  EM.connect(options[:host], options[:port], IrcClient, options)
end