class Net::IRC::Client
  include Net::IRC
  include Constants

  attr_reader :host, :port, :opts
  attr_reader :prefix, :channels

  def initialize(host, port, opts={})
    @host          = host
    @port          = port
    @opts          = OpenStruct.new(opts)
    @log           = @opts.logger || ::Logger.new($stdout)
    @server_config = Message::ServerConfig.new
    @channels = {
#      "#channel" => {
#        :modes => [],
#        :users => [],
#      }
    }
    @channels.extend(MonitorMixin)
  end

  # Connect to server and start loop.
  def start
    # reset config
    @server_config = Message::ServerConfig.new
    @socket = TCPSocket.new(@host, @port)
    on_connected
    post PASS, @opts.pass if @opts.pass
    post NICK, @opts.nick
    post USER, @opts.user, "0", "*", @opts.real

    buffer = BufferedTokenizer.new("\r\n")

    while data = @socket.readpartial(4096)
      buffer.extract(data).each do |line|
        l = "#{line}\r\n"
        begin
          @log.debug "RECEIVE: #{l.chomp}"
          m = Message.parse(l)
          next if on_message(m) === true
          name = "on_#{(COMMANDS[m.command.upcase] || m.command).downcase}"
          send(name, m) if respond_to?(name)
        rescue Exception => e
          warn e
          warn e.backtrace.join("\r\t")
          raise
        rescue Message::InvalidMessage
          @log.error "MessageParse: " + l.inspect
        end
      end
    end
  rescue IOError
  ensure
    finish
  end

  # Close connection to server.
  def finish
    begin
      @socket.close
    rescue
    end
    on_disconnected
  end

  # Catch all messages.
  # If this method return true, aother callback will not be called.
  def on_message(m)
  end

  # Default RPL_WELCOME callback.
  # This sets @prefix from the message.
  def on_rpl_welcome(m)
    @prefix = Prefix.new(m[1][/\S+\z/])
  end

  # Default RPL_ISUPPORT callback.
  # This detects server's configurations.
  def on_rpl_isupport(m)
    @server_config.set(m)
  end

  # Default PING callback. Response PONG.
  def on_ping(m)
    post PONG, @prefix ? @prefix.nick : ""
  end

  # Call when socket connected.
  def on_connected
  end

  # Call when socket closed.
  def on_disconnected
  end

  private

  # Post message to server.
  #
  #     include Net::IRC::Constants
  #     post PRIVMSG, "#channel", "foobar"
  def post(command, *params)
    m = Message.new(nil, command, params.map {|s|
      if s
        s.force_encoding("ASCII-8BIT") if s.respond_to? :force_encoding
        #s.gsub(/\r\n|[\r\n]/, " ")
        s.tr("\r\n", " ")
      else
        ""
      end
    })

    @log.debug "SEND: #{m.to_s.chomp}"
    @socket << m.to_s
  end
end # Client