from django.contrib.gis.db import models

from ..utils import gisfield_may_be_null

class NamedModel(models.Model):

    name = models.CharField(max_length=30)

    class Meta:

        abstract = True

    def __str__(self):

        return self.name

class Country(NamedModel):

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

class CountryWebMercator(NamedModel):

    mpoly = models.MultiPolygonField(srid=3857)

class City(NamedModel):

    point = models.PointField()

    class Meta:

        app_label = "geoapp"

# This is an inherited model from City

class PennsylvaniaCity(City):

    county = models.CharField(max_length=30)

    founded = models.DateTimeField(null=True)

    class Meta:

        app_label = "geoapp"

class State(NamedModel):

    poly = models.PolygonField(

        null=gisfield_may_be_null

    )  # Allowing NULL geometries here.

    class Meta:

        app_label = "geoapp"

class Track(NamedModel):

    line = models.LineStringField()

class MultiFields(NamedModel):

    city = models.ForeignKey(City, models.CASCADE)

    point = models.PointField()

    poly = models.PolygonField()

class UniqueTogetherModel(models.Model):

    city = models.CharField(max_length=30)

    point = models.PointField()

    class Meta:

        unique_together = ("city", "point")

        required_db_features = ["supports_geometry_field_unique_index"]

class Truth(models.Model):

    val = models.BooleanField(default=False)

class Feature(NamedModel):

    geom = models.GeometryField()

class MinusOneSRID(models.Model):

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

class NonConcreteField(models.IntegerField):

    def db_type(self, connection):

        return None

    def get_attname_column(self):

        attname, column = super().get_attname_column()

        return attname, None

class NonConcreteModel(NamedModel):

    non_concrete = NonConcreteField()

    point = models.PointField(geography=True)

class ManyPointModel(NamedModel):

    point1 = models.PointField()

    point2 = models.PointField()

    point3 = models.PointField(srid=3857)