class DEBUGGER__::UI_ServerBase

def greeting
  case g = @sock.gets
  when /^info cookie:\s+(.*)$/
    require 'etc'
    check_cookie $1
    @sock.puts "PID: #{Process.pid}, $0: #{$0}, session_name: #{CONFIG[:session_name]}"
    @sock.puts "debug #{VERSION} on #{RUBY_DESCRIPTION}"
    @sock.puts "uname: #{Etc.uname.inspect}"
    @sock.close
    raise GreetingError, "HEAD request"
  when /^version:\s+(\S+)\s+(.+)$/
    v, params = $1, $2
    # TODO: protocol version
    if v != VERSION
      @sock.puts msg = "out DEBUGGER: Incompatible version (server:#{VERSION} and client:#{$1})"
      raise GreetingError, msg
    end
    parse_option(params)
    session_name = CONFIG[:session_name]
    session_name_str = ", session_name:#{session_name}" if session_name
    puts "DEBUGGER (client): Connected. PID:#{Process.pid}, $0:#{$0}#{session_name_str}"
    puts "DEBUGGER (client): Type `Ctrl-C` to enter the debug console." unless @need_pause_at_first
    puts
  when /^Content-Length: (\d+)/
    require_relative 'server_dap'
    raise unless @sock.read(2) == "\r\n"
    self.extend(UI_DAP)
    @repl = false
    @need_pause_at_first = false
    dap_setup @sock.read($1.to_i)
  when /^GET\s\/json\sHTTP\/1.1/, /^GET\s\/json\/version\sHTTP\/1.1/, /^GET\s\/\w{8}-\w{4}-\w{4}-\w{4}-\w{12}\sHTTP\/1.1/
    # The reason for not using @uuid here is @uuid is nil if users run debugger without `--open=chrome`.
    require_relative 'server_cdp'
    self.extend(UI_CDP)
    send_chrome_response g
  else
    raise GreetingError, "Unknown greeting message: #{g}"
  end
end