require "sockets/proxies/socks"

module Sockets
  module Proxies
    class SOCKS4 < SOCKS
      VERSION = 0x04

      protected
        def greet(socket)
          # noop
        end

        def authenticate(socket, method)
          # noop
        end

        def connect(socket, host, port)
          begin
            ip = IPAddr.new(host)
          rescue ArgumentError
            ip = IPAddr.new(Socket.getaddrinfo(host, nil, :INET, :STREAM).first)
          end

          socket << [VERSION, 0x01, port].pack("CCn") << ip.hton
          socket << user if user
          socket << 0x00

          version, status, port = socket.read(4).unpack("CCn")
          check_version(version, 0x00)
          ip = IPAddr.ntop(socket.read(4))

          case status
            when 0x5A # request granted
            when 0x5B # request rejected or failed
              raise "request rejected or failed"
            when 0x5C # request rejected becasue SOCKS server cannot connect to identd on the client
              raise "request rejected becasue SOCKS server cannot connect to identd on the client"
            when 0x5D # request rejected because the client program and identd report different user-ids
              raise "request rejected because the client program and identd report different user-ids"
            else
                raise "unknown SOCKS error"
          end
        end
    end
  end
end