// 取得當月1號
function getMonthFirstDay()
{
  var firstday = new Date();
  firstday.setDate(1);
  return (firstday.toFormat("yyyymmdd"));  
}

// 取得當月最後一天
function getMonthLastDay()
{
  var lastday = new Date();
  lastday.setDate(1);
  lastday = lastday.DateAdd("m", 1);
  lastday = lastday.DateAdd("d", -1);
  return (lastday.toFormat("yyyymmdd"));  

}

// 取得起時到迄時之時間(分鐘數)
// 傳入為分鐘數, 如 08:30 傳入 510 (8*60+30)
function getTimeRange(time_from, time_to)
{

  if (time_from === "" || time_to === "") return "";
  if (time_from >= 1440) time_from = time_from % 1440;
  if (time_to >= 1440) time_to = time_to % 1440;

  if (time_to < time_from) // 跨夜 ex: 21:00~03:00
    {
       return (1440 - time_from) + time_to;
    }
  else
    {
       return time_to - time_from;
    }  

}

// 檢查休息時段(off_from, off_to)是否在班表時段(time_from, time_to)
function isInTimeRange(time_from, time_to, off_from, off_to)
{
  if (time_from === "" || time_to === "") return false;
  if (off_from === "" || off_to === "") return false;
//  
  if (time_to < time_from) // 跨夜 ex: 21:00~03:00
    {
       if (off_from < time_from && off_from > time_to)
          return false;
       if (off_to < time_from &&  off_to > time_to)
          return false;
       return true;   
    }
  else
    {
      if (off_from < time_from || off_from > time_to)
         return false;
      if (off_to < time_from || off_to > time_to)
         return false;
      return true;   
    }  
}

// 輸入分鐘數, 取得 X時Y分
function getChineseHHMM(mm)
{
  return parseInt((mm / 60)) + "時" + (mm % 60) + "分";
}