#!/usr/bin/env ruby

#------ PhidgetSaver.rb: Phidgetでスクリーンセーバー-------#
#------------------- By Koji Tsukada 2005/11 --------------#


require "socket"
require "dl/import"

module Win32
  extend DL::Importable
  
  typealias "DWORD", "unsigned long"
  typealias "BYTE", "unsigned char"
  typealias "ULONG", "unsigned long"
  
  KEYEVENTF_KEYUP = 0x02
  VK_SHIFT = 0x10
  
  dlload "user32.dll"
  extern "void keybd_event(BYTE, BYTE, DWORD, ULONG)"
  
  def send_keybd_event(bVk, dwFlags = 0)
    keybd_event(bVk, 0, dwFlags, 0)
  end

  module_function :send_keybd_event
end

module PhidgetApplication
  class PhidgetSaver
  
    def initialize(ip = "127.0.0.1", port = 4321, threshold = 200, file = "logon.scr")
      main(ip, port, threshold, file)
    end
  
    def main(ip, port, threshold, file)
      socket = TCPSocket.new(ip, port)
      while line = socket.gets
        level = parse(line.chomp)
         p level.to_s
        if(level != nil)
          if check_brightness?(level, threshold)
            start_screen_saver(file)
          else
            stop_screen_saver
          end
        end
      end
      socket.close
    end

    def check_brightness?(level, threshold)
      flag = false
      flag = true if level > threshold
    end
  
    def parse(line)
      args = line.split(",")
      if args[0] == "In" and
         args[1] == "InterfaceKit" and
         args[2] == "Analog"
        case args[3]
          when "0"
            level = args[4].to_i
        end
      end
      level
    end
    
    def start_screen_saver(file)
      if(!@saver_working)
        system "cygstart #{file}"
        @saver_working = true
      end
    end
    
    def stop_screen_saver
      if(@saver_working)
        Win32.send_keybd_event(Win32::VK_SHIFT)
        Win32.send_keybd_event(Win32::VK_SHIFT, Win32::KEYEVENTF_KEYUP)
        @saver_working = false
      end
    end
  end
  
     
  #############################################
  #プログラム開始
  #############################################
  case ARGV.length
    when 0:
      puts "Usage: PhidgetSaver [ip] [port] [threshold] [saver_file]"
      PhidgetSaver.new()
    when 2:
      PhidgetSaver.new(ARGV[0], ARGV[1].to_i)
    when 3:
      PhidgetSaver.new(ARGV[0], ARGV[1].to_i, ARGV[2].to_i)
    when 4:
      PhidgetSaver.new(ARGV[0], ARGV[1].to_i, ARGV[2].to_i, ARGV[3])
    else
      puts "Usage: PhidgetSaver [ip] [port] [threshold] [saver_file]"
      exit(0)
  end
end