from django.db import models

class Photo(models.Model):
    """
    A photo for my site
    """
    title = models.CharField(maxlength=50)
    photo = models.ImageField(upload_to="photos/")
    thumbnail = models.ImageField(upload_to="thumbnails/", editable=False)
    
    def save(self):
        if not self.thumbnail:
            # We use PIL's Image object
            # Docs: http://www.pythonware.com/library/pil/handbook/image.htm
            from PIL import Image
        
            # Set our max thumbnail size in a tuple (max width, max height)
            THUMBNAIL_SIZE = (50, 50)
        
            # Save fake thumbnail as empty so we can get the filename from the 
            # original filename, from Django's convenience method 
            # get_FIELD_filename()
            self.save_thumbnail_file(self.get_photo_filename(), '')
        
            # Open original photo which we want to thumbnail using PIL's Image
            # object
            image = Image.open(self.get_photo_filename())
        
            # Convert to RGB if necessary
            # Thanks to Limodou on DjangoSnippets.org
            # http://www.djangosnippets.org/snippets/20/
            if image.mode not in ('L', 'RGB'):
                image = image.convert('RGB')
        
            # We use our PIL Image object to create the thumbnail, which already
            # has a thumbnail() convenience method that contrains proportions.
            # Additionally, we use Image.ANTIALIAS to make the image look better.
            # Without antialiasing the image pattern artifacts may result.
            image.thumbnail(THUMBNAIL_SIZE, Image.ANTIALIAS)
        
            # Save the thumbnail
            image.save(self.get_thumbnail_filename())
        
        # Save this photo instance
        super(Photo, self).save()

    class Admin:
        pass

    def __str__(self):
        return self.title