local scheduler = {}

socket = require('socket')

function scheduler.Timer(init)
  -- the new instance
  
  local self = {
    -- public fields go in the instance table
    interval  = init
  }

  local function millis()
  	return socket.gettime()*1000
  end
  
  -- private fields are implemented using locals
  -- they are faster than table access, and are truly private, 
  -- so the code that uses your class can't get them
  
  local _timestamp = millis()
  local _running   = true
  
  function self.elapsed()
    if _running and (millis() - _timestamp ) >= self.interval then
        _running = false
    	return true
    else
    	return false
    end 
  end

  function self.running()
  	return (millis() - _timestamp ) < self.interval
  end

  function self.restart()
  	_timestamp = millis()
  	_running = true
  end
  
  function self.count()
    return millis() - timestamp
  end
  
  -- return the instance
  return self
end

return scheduler