import logging
from data.database import Image, ImageStorage, db
from app import app

logger = logging.getLogger(__name__)

def backfill_parent_id():
  logger.setLevel(logging.DEBUG)

  logger.debug('backfill_parent_id: Starting')
  logger.debug('backfill_parent_id: This can be a LONG RUNNING OPERATION. Please wait!')

  # Check for any images without parent
  has_images = bool(list(Image
                         .select(Image.id)
                         .join(ImageStorage)
                         .where(Image.parent >> None, Image.ancestors != '/', ImageStorage.uploading == False)
                         .limit(1)))

  if not has_images:
    logger.debug('backfill_parent_id: No migration needed')
    return

  while True:
    # Load the record from the DB.
    batch_images_ids = list(Image
                            .select(Image.id)
                            .join(ImageStorage)
                            .where(Image.parent >> None, Image.ancestors != '/', ImageStorage.uploading == False)
                            .limit(100))

    if len(batch_images_ids) == 0:
      logger.debug('backfill_parent_id: Completed')
      return

    for image_id in batch_images_ids:
      with app.config['DB_TRANSACTION_FACTORY'](db):
        try:
          image = Image.select(Image.id, Image.ancestors).where(Image.id == image_id).get()
          image.parent = image.ancestors.split('/')[-2]
          image.save()
        except Image.DoesNotExist:
          pass

if __name__ == "__main__":
  logging.basicConfig(level=logging.DEBUG)
  logging.getLogger('peewee').setLevel(logging.CRITICAL)

  backfill_parent_id()