from django.db import models
from django.db.models import permalink
from django.contrib import admin
from fields import ThumbnailImageField

class Item(models.Model):
    name = models.CharField(max_length=250)
    description = models.TextField()

    class Meta:
        ordering = ['name']
        
    def __unicode__(self):
        return self.name
        
    @permalink
    def get_absolute_url(self):
        return ('item_detail', None, {'object_id': self.id})

class Photo(models.Model):
    item = models.ForeignKey(Item)
    title = models.CharField(max_length=100)
    image = ThumbnailImageField(upload_to='photos')
    caption = models.CharField(max_length=250, blank=True)
        
    class Meta:
        ordering = ['title']
        
    def __unicode__(self):
        return self.title

    @permalink
    def get_absolute_url(self):
        return ('photo_detail', None, {'object_id': self.id})

class PhotoInline(admin.StackedInline):
    model = Photo

class ItemAdmin(admin.ModelAdmin):
    inlines = [PhotoInline]

admin.site.register(Photo)
admin.site.register(Item, ItemAdmin)    

from django.db.models.fields.files import ImageField, ImageFieldFile
import Image
import os

def _add_thumb(s):
    """
    Modifies a string (filename, URL) containing an image filename, to insert
    '.thumb'
    """
    parts = s.split(".")
    parts.insert(-1, "thumb")
    if parts[-1].lower() not in ['jpeg', 'jpg']:
        parts[-1] = 'jpg'
    return ".".join(parts)

class ThumbnailImageFieldFile(ImageFieldFile):
    def _get_thumb_path(self):
        return _add_thumb(self.path)
    thumb_path = property(_get_thumb_path)
    
    def _get_thumb_url(self):
        return _add_thumb(self.url)
    thumb_url = property(_get_thumb_url)

    def save(self, name, content, save=True):
        super(ThumbnailImageFieldFile, self).save(name, content, save)
        img = Image.open(self.path)
        img.thumbnail(
            (self.field.thumb_width, self.field.thumb_height),
            Image.ANTIALIAS
        )
        img.save(self.thumb_path, 'JPEG')

    def delete(self, save=True):
        if os.path.exists(self.thumb_path):
            os.remove(self.thumb_path)
        super(ThumbnailImageFieldFile, self).delete(save)


class ThumbnailImageField(ImageField):
    """
    Behaves like a regular ImageField, but stores an extra (JPEG) thumbnail
    image, providing FIELD.thumb_url and FIELD.thumb_path.
    
    Accepts two additional, optional arguments: thumb_width and thumb_height,
    both defaulting to 128 (pixels). Resizing will preserve aspect ratio while
    staying inside the requested dimensions; see PIL's Image.thumbnail()
    method documentation for details.
    """
    attr_class = ThumbnailImageFieldFile

    def __init__(self, thumb_width=128, thumb_height=128, *args, **kwargs):
        self.thumb_width = thumb_width
        self.thumb_height = thumb_height
        super(ThumbnailImageField, self).__init__(*args, **kwargs)

gallary/
          /gallary/
                     /__init__.py
                     /context_processors.py
                     /real_urls.py
                     /setting.py
                     /urls.py
                     /wsgi.py
           /item
                     /templates/
                     /media/
                     /__init__.py
                     /fields.py
                     /models.py
                     /test.py
                     /urls.py
                     /views.py
           /manage.py

INSTALLED_APPS = (
    'django.contrib.auth',
    'django.contrib.contenttypes',
    'django.contrib.sessions',
    'django.contrib.sites',
    'django.contrib.admin',
    'gallery.items',
)