# MODEL
def images_directory_path(instance, filename):
    return 'images/client_id_{0}/{1}'.format(instance.client.id, filename)


class Image(models.Model):
    created = models.DateTimeField(auto_now_add=True)
    updated = models.DateTimeField(auto_now=True)
    client = models.ForeignKey('client.Client', related_name='client_image', on_delete=models.CASCADE)

    image_file = models.ImageField(upload_to=images_directory_path)

# SERIALIZER
class ImageSerializer(serializers.ModelSerializer):
    class Meta:
        model = Image
        read_only_fields = ['id', 'created', 'updated']
        exclude = ('client',)

    def update(self, instance, validated_data):
        fields = instance._meta.fields
        exclude = ['id', 'created', 'updated', 'client']
        for field in fields:
            field = field.name.split('.')[-1]
            if field in exclude:
                continue
            setattr(instance, field, validated_data.get(field, getattr(instance, field)))
        instance.save()

        if "client" in self.context.keys():
            validated_data["client"] = self.context["client"]
            if instance.client != validated_data["client"]:
                new_object = Image.objects.create(
                    client=validated_data["client"],
                    image_file=instance.image_file
                )
                instance.delete()
                instance = new_object
                return instance

        return instance