class Protobuf::Rpc::SocketServer

def cleanup? 
  # every 10 connections run a cleanup routine after closing the response
  @threads.size > (@thread_threshold - 1) && (@threads.size % @thread_threshold) == 0
end

def cleanup_threads
  log_debug "[#{log_signature}] Thread cleanup - #{@threads.size} - start"
  @threads = @threads.select do |t| 
    if t[:thread].alive? 
      true  
    else
      t[:thread].join
      @working.delete(t[:socket])
      false
    end
  end
  log_debug "[#{log_signature}] Thread cleanup - #{@threads.size} - complete"
end

def log_signature
  @log_signature ||= "server-#{self}"
end

def new_worker(socket)
  Thread.new(socket) do |sock|
    Protobuf::Rpc::SocketServer::Worker.new(sock) do |s|
      s.close
    end
  end
end

def run(host = "127.0.0.1", port = 9399, backlog = 100, thread_threshold = 100)
  log_debug "[#{log_signature}] Run"
  @running = true
  @threads = []
  @thread_threshold = thread_threshold
  @server = TCPServer.new(host, port)
  @server.listen(backlog)
  @working = []
  @listen_fds = [@server]
  while running?
    log_debug "[#{log_signature}] Waiting for connections"
    if ready_cnxns = IO.select(@listen_fds, [], [], 20)
      cnxns = ready_cnxns.first
      cnxns.each do |client|
        case 
        when !running? then
          # no-op
        when client == @server then 
          log_debug "[#{log_signature}] Accepted new connection"
          client, sockaddr = @server.accept
          @listen_fds << client
        else 
          if !@working.include?(client)
            @working << @listen_fds.delete(client)
            log_debug "[#{log_signature}] Working" 
            @threads << { :thread => new_worker(client), 
                          :socket => client }
            cleanup_threads if cleanup?
          end
        end
      end
    else
      # Run a cleanup if select times out while waiting
      cleanup_threads if @threads.size > 1
    end
  end
rescue 
  # Closing the server causes the loop to raise an exception here
  raise if running?
end

def running?
  @running
end

def stop 
  @running = false
  @server.close
end