from django.contrib.gis.db import models

from django.contrib.gis.tests.utils import mysql, spatialite

# MySQL spatial indices can't handle NULL geometries.

null_flag = not mysql

class Country(models.Model):

    name = models.CharField(max_length=30)

    mpoly = models.MultiPolygonField() # SRID, by default, is 4326

    objects = models.GeoManager()

    def __unicode__(self): return self.name

class City(models.Model):

    name = models.CharField(max_length=30)

    point = models.PointField()

    objects = models.GeoManager()

    def __unicode__(self): return self.name

# This is an inherited model from City

class PennsylvaniaCity(City):

    county = models.CharField(max_length=30)

    objects = models.GeoManager() # TODO: This should be implicitly inherited.

class State(models.Model):

    name = models.CharField(max_length=30)

    poly = models.PolygonField(null=null_flag) # Allowing NULL geometries here.

    objects = models.GeoManager()

    def __unicode__(self): return self.name

if not spatialite:

    class Feature(models.Model):

        name = models.CharField(max_length=20)

        geom = models.GeometryField()

        objects = models.GeoManager()

        def __unicode__(self): return self.name

    class MinusOneSRID(models.Model):

        geom = models.PointField(srid=-1) # Minus one SRID.

        objects = models.GeoManager()