module OSC
  class Server
    def initialize(port)
      @socket = UDPSocket.new
      @socket.bind('', port)
      @matchers = []
      @queue = Queue.new
    end

    def run
      start_dispatcher

      start_detector
    end

    def stop
      @socket.close
    end

    def add_method(address_pattern, &proc)
      matcher = AddressPattern.new(address_pattern)

      @matchers << [matcher, proc]
    end

    private

    def start_detector
      begin
        detector
      rescue
        Thread.main.raise($!)
      end
    end

    def start_dispatcher
      Thread.fork do
        begin
          dispatcher
        rescue
          Thread.main.raise($!)
        end
      end
    end

    def dispatcher
      loop do
        mesg = @queue.pop
        dispatch_message(mesg)
      end
    end

    def dispatch_message(message)
      diff = (message.time || 0) - Time.now.to_ntp

      if diff <= 0
        sendmesg(message)
      else # spawn a thread to wait until it's time
        Thread.fork do
          sleep(diff)
          sendmesg(message)
          Thread.exit
        end
      end
    end

    def sendmesg(mesg)
      @matchers.each do |matcher, proc|
        if matcher.match?(mesg.address)
          proc.call(mesg)
        end
      end
    end

    def detector
      loop do
        osc_data, network = @socket.recvfrom(16384)
        begin
          ip_info = Array.new
          ip_info << network[1]
          ip_info.concat(network[2].split('.'))
          OSCPacket.messages_from_network( osc_data, ip_info ).each do |message|
            @queue.push(message)
          end

        rescue(EOFError)
        end
      end
    end
  end
end