require 'socket'

class SelectChatServer < TCPServer

  def initialize(host,port)
    super host, port
    @sockets = [self]
  end

  def start
    while(1)
      rs,ws,es = IO.select(@sockets,[], @sockets)

      rs.each do | read_socket |
        # if it's the server, accept the connection
        # and add the socket to the list of clients to except
        if read_socket == self
          $stdout.puts "Got client"
          client = self.accept
          # Here we use module extension to add custom
          # properties and methods to a socket!
          client.extend(ChatClient)
          client.username = 'test'
          @sockets << client
        # need to throw out dead sockets
        elsif read_socket.closed? or read_socket.eof?
          # kill the whole thing if it's the server
          exit if read_socket == self
          $stdout.puts "Client closed connection"
          # remove the socket from the connected sockets list
          @sockets.reject! { |socket| socket == read_socket }
        else
          $stdout.puts "Got client data"
          data = read_socket.readline
          $stdout.puts data
          # write the data to all the other sockets except the server listener socket
          # and the author socket
          @sockets.map { | socket | socket.puts data unless socket == read_socket or item == self }
        end
      end

      # throw out any sockets with errors
      es.each do | err_socket |
        $stderr.puts "Client error"
        @sockets.reject! { |socket| socket == err_socket }
      end

    end
  end

end

# an example of a module to provide a custom
# username property to a socket
module ChatClient
  attr_accessor :username
end

server = SelectChatServer.new("localhost", 3829)
server.start