import logging

from util.config.validators import BaseValidator, ConfigValidationException
from util.timedeltastring import convert_to_timedelta

logger = logging.getLogger(__name__)

class TimeMachineValidator(BaseValidator):
  name = "time-machine"

  @classmethod
  def validate(cls, validator_context):
    config = validator_context.config

    if not 'DEFAULT_TAG_EXPIRATION' in config:
      # Old style config
      return

    try:
      convert_to_timedelta(config['DEFAULT_TAG_EXPIRATION']).total_seconds()
    except ValueError as ve:
      raise ConfigValidationException('Invalid default expiration: %s' % ve.message)

    if not config['DEFAULT_TAG_EXPIRATION'] in config.get('TAG_EXPIRATION_OPTIONS', []):
      raise ConfigValidationException('Default expiration must be in expiration options set')

    for ts in config.get('TAG_EXPIRATION_OPTIONS', []):
      try:
        convert_to_timedelta(ts)
      except ValueError as ve:
        raise ConfigValidationException('Invalid tag expiration option: %s' % ts)