Help with updating model images automatically

[ste_a47]

I'd like to implement a functionality in an app of mine, but I don't know how to go about it. What I want is this: I have a model class that uses imagekit to save its images, and I'd like to have the users being able to update the images easily for the vehicles without having to edit each respective vehicle record.

How they'll do this is that there will be a folder named originals and it'll contain folders for each vehicle in the format <stock_number>/PUBLIC If a user moves images into the PUBLIC folder for a vehicle, when the script is executed, it'll compare those images with the current ones and update them if those in the PUBLIC folder are newer. If the record has no images, then they will be added. Also, if the images have been deleted from the site_media directory, then their links should be deleted from the database.

How can I go about this in an efficient way? My models are as below:

class Photo(ImageModel):
   name = models.CharField(max_length = 100)
   original_image = models.ImageField(upload_to = 'photos')
   num_views = models.PositiveIntegerField(editable = False, default=0)
   position = models.ForeignKey(PhotoPosition)
   content_type = models.ForeignKey(ContentType)
   object_id = models.PositiveIntegerField()
   content_object = generic.GenericForeignKey('content_type', 'object_id')

   class IKOptions:
      spec_module = 'vehicles.specs'
      cache_dir = 'photos'
      image_field = 'original_image'
      save_count_as = 'num_views'


class Vehicle(models.Model):
   objects = VehicleManager()
   stock_number = models.CharField(max_length=6, blank=False, unique=True)
   vin = models.CharField(max_length=17, blank=False)
   ....
   images = generic.GenericRelation('Photo', blank=True, null=True)

Ideally, what I want is something like the functionality galleria offers. This has been a major obstacle for me so I hope some one here can help me out.