透過列舉來減少if..else

原始碼: 又臭又長

def parse_time(time_str):
  now = datetime.now()
  if '剛剛' in time_str:
    return now
  elif '秒前' in time_str:
    seconds = int(time_str.split('秒前')[0])
    return now - timedelta(seconds=seconds)
  elif '分鐘前' in time_str:
    minutes = int(time_str.split('分鐘前')[0])
    return now - timedelta(minutes=minutes)
  elif '小時前' in time_str:
    hours = int(time_str.split('小時前')[0])
    return now - timedelta(hours=hours)
  elif '今天' in time_str:
    return None
    # time_format = re.search(r'今天 (\d+:\d+)', time_str).group(1)
    # return datetime.strptime(f'{now.year}-{now.month}-{now.day} {time_format}', '%Y-%m-%d %H:%M')
  else:
    try:
      return datetime.strptime(time_str, '%m月%d日 %H:%M')
    except ValueError:
      try:
        return datetime.strptime(time_str, '%Y-%m-%d %H:%M')
      except ValueError:
        try:
          return datetime.strptime(time_str, '%Y年%m月%d日 %H:%M')
        except ValueError:
          return None

列舉:

class TimeFormat(Enum):
  JUST_NOW=(r'剛剛',lambda m:datetime.now())
  SECONDS_AGO=(r'(\d+)秒前',lambda m:datetime.now()-timedelta(seconds=int(m.group(1))))
  MINUTES_AGO=(r'(\d+)分鐘前',lambda m:datetime.now()-timedelta(minutes=int(m.group(1))))
  HOURS_AGO=(r'(\d+)小時前',lambda m:datetime.now()-timedelta(hours=int(m.group(1))))
  TODAY=(r'今天',lambda m:None)
  MONTH_DAY_TIME = (r'(\d+)月(\d+)日 (\d+:\d+)', lambda m: datetime.strptime(f'{datetime.now().year}-{datetime.now().month}-{datetime.now().day}-{m.group(1)}', '%Y-%m-%d %H:%M:%S'))
  YEAR_MONTH_DAY_TIME=(r'(\d{4})-(\d{2})-(\d{2}) (\d{2}):(\d{2}))',lambda m:datetime.strptime(f'{datetime.now().year}-{m.group(1)}-{m.group(2)}-{m.group(3)}','%Y-%m-%d %H:%M'))
  FULL_DATE_TIME=(r'(\d{4})年(\d{2})月(\d{2})日 (\d{2}):(\d{2}))',lambda m:datetime.strptime(m.group(0),'%Y-%m-%d %H:%M'))

def parse_time(time_str):
  for time_format in TimeFormat:
    pattern,handler=time_format.value
    match=re.search(pattern,time_str)
    if match:
      return handler(match)
  return None