gistfile1.py

from django.db import models
from polymorphic.polymorphic_model import PolymorphicModel
from cms.models.fields import PlaceholderField
from django.db.models.signals import pre_save
from django.template.defaultfilters import slugify

class Slugifier(object):
    def __init__(self, model, target, source):
        self.model = product
        self.target = slug
        self.source = manufacturer + name
        field = self.model._meta.get_field_by_name(self.target)[0]
        self.max_length = field.max_length
        
    def __call__(self, instance, **kwargs):
        if getattr(instance, self.target):
            return
        slug = slugify(getattr(instance, self.source))[:self.max_length]
        current = slug
        index = 0
        while self.model.objects.filter(**{self.target: current}).exists():
            suffix = '-%s' % index
            current = '%s%s'  % (slug[:-len(suffix)], suffix)
            index += 1
        setattr(instance, self.target, current)

def auto_slug(target, source):
    """
    @auto_slug('slug', 'name')
    class MyModel(models.Model):
        name = models.CharField(max_length=255)
        slug = models.SlugField(max_length=255, null=True)
    """
    def _decorator(cls):
        pre_save.connect(Slugifier(cls, target, source), sender=cls, weak=False)
        return cls
    return _decorator


# Define some models that will allow for multiple choice inputs
# this will make adding new products alot quicker/easier

class Manufacturer(models.Model):
    name = models.CharField(max_length=50, unique=True)
    
    def __unicode__(self):
        return self.name
        

class Backing(models.Model):
    name = models.CharField(max_length=50, unique=True)
    
    def __unicode__(self):
        return self.name
  
  
class Classification(models.Model):
    rating = models.CharField(max_length=50, unique=True)
    
    def __unicode__(self):
        return self.name
        
        
class Width(models.Model):
    widths = models.CharField(max_length=50, unique=True)
    
    def __unicode__(self):
        return self.name
        
        
class PileType(models.Model):
    pile_tpye = models.CharField(max_length=50,unique=True)
    
    def __unicode__(self):
        return self.name
        
class SlipRating(models.Model):
    pile_tpye = models.CharField(max_length=50,unique=True)
    
    def __unicode__(self):
        return self.name
        

# Define a base product model

@auto_slug('slug', 'name')
class Product(PolymorphicModel):
    name = models.CharField(max_length=50, unique=True)
    slug = models.CharField(max_length=50, unique=True)
    manufacturer = models.ForeignKey(Manufacturer) 
    description = PlaceholderField('product_description')
    
    def __unicode__(self):
        return self.name
        

# Defining sub class of the base product model

class Carpet(Product):
    pile_construction = models.CharField(max_length=50)
    backing = models.ForeignKey(Backing)
    classification = models.ForeignKey(Classification)
    widths = models.ForeignKey(Width)
    pile_type = models.ForeignKey(PileType)
    tog_rating = models.CharField(max_length=50)
    
       
    def __unicode__(self):
        return self.name
        
        
class Vinyl(Product):
    classification = models.ForeignKey(Classification)
    wear_layer = models.CharField(max_length=50)
    thickness = models.CharField(max_length=50)
    slip_rating = models.ForeignKey(SlipRating)
    widths = models.ForeignKey(Width)
    
    def __unicode__(self):
        return self.name
        
        
class Laminate(Product):
    classification = models.ForeignKey(Classification)
    pack_size = models.CharField(max_length=50)
    
    def __unicode__(self):
        return self.name
        
        
class LVT(Product):
    classification = models.ForeignKey(Classification)
    wear_layer = models.CharField(max_length=50)
    pack_size = models.CharField(max_length=50)
    
    class Meta:
        verbose_name_plural = 'LVT'
    
    def __unicode__(self):
        return self.name
        
        
class CarpetTile(Product):
    pile_construction = models.CharField(max_length=50)
    pile_type = models.ForeignKey(PileType)
    backing = models.ForeignKey(Backing)
    classification = models.ForeignKey(Classification)
    pack_size = models.CharField(max_length=50)

    def __unicode__(self):
        return u'%s' % (self.name)
        
        
class Underlay(Product):
    construction = models.CharField(max_length=50)
    backing = models.ForeignKey(Backing)
    classification = models.ForeignKey(Classification)
    tog_rating = models.CharField(max_length=50)
    roll_size = models.CharField(max_length=50)
    
       
    def __unicode__(self):
        return self.name
        
        
class Adhesive(Product):
    coverage = models.CharField(max_length=50)
    shelf_life = models.CharField(max_length=50)
   
    def __unicode__(self):
        return self.name
        
        
class Screed(Product):
    coverage = models.CharField(max_length=50)
    shelf_life = models.CharField(max_length=50)
   
    def __unicode__(self):
        return self.name
        
        
class Accessory(Product):
    reference = models.CharField(max_length=255)
    
    class Meta:
        verbose_name_plural = 'Accessories'
    
    def __unicode__(self):
        return u'%s' % (self.product)