Fixed #25636 -- Dropped support for SpatiaLite < 3.0

"""

SQL functions reference lists:

http://www.gaia-gis.it/spatialite-2.4.0/spatialite-sql-2.4.html

http://www.gaia-gis.it/spatialite-3.0.0-BETA/spatialite-sql-3.0.0.html

http://www.gaia-gis.it/gaia-sins/spatialite-sql-4.2.1.html

"""

from django.contrib.gis.measure import Distance

from django.core.exceptions import ImproperlyConfigured

from django.db.backends.sqlite3.operations import DatabaseOperations

from django.db.utils import DatabaseError

from django.utils import six

from django.utils.functional import cached_property

    distance = 'Distance'

    envelope = 'Envelope'

    extent = 'Extent'

    geojson = 'AsGeoJSON'

    gml = 'AsGML'

    intersection = 'Intersection'

    kml = 'AsKML'

    length = 'GLength'  # OpenGis defines Length, but this conflicts with an SQLite reserved keyword

    num_geom = 'NumGeometries'

    num_points = 'NumPoints'

                'database (error was "%s").  Was the SpatiaLite initialization '

                'SQL loaded on this database?') % (self.connection.settings_dict['NAME'], msg)

            six.reraise(ImproperlyConfigured, ImproperlyConfigured(new_msg), sys.exc_info()[2])

        if version < (2, 4, 0):

            raise ImproperlyConfigured('GeoDjango only supports SpatiaLite versions '

                                       '2.4.0 and above')

        if version < (3, 0, 0):

            raise ImproperlyConfigured('GeoDjango only supports SpatiaLite versions 3.0.0 and above.')

        return version

    @property

    def _version_greater_2_4_0_rc4(self):

        if self.spatial_version >= (2, 4, 1):

            return True

        else:

            # Spatialite 2.4.0-RC4 added AsGML and AsKML, however both

            # RC2 (shipped in popular Debian/Ubuntu packages) and RC4

            # report version as '2.4.0', so we fall back to feature detection

            try:

                self._get_spatialite_func("AsGML(GeomFromText('POINT(1 1)'))")

            except DatabaseError:

                return False

            return True

    @cached_property

    def disallowed_aggregates(self):

        disallowed = (aggregates.Extent3D, aggregates.MakeLine)

        if self.spatial_version < (3, 0, 0):

            disallowed += (aggregates.Collect, aggregates.Extent)

        return disallowed

    @cached_property

    def gml(self):

        return 'AsGML' if self._version_greater_2_4_0_rc4 else None

    @cached_property

    def kml(self):

        return 'AsKML' if self._version_greater_2_4_0_rc4 else None

    @cached_property

    def geojson(self):

        return 'AsGeoJSON' if self.spatial_version >= (3, 0, 0) else None

    def convert_extent(self, box, srid):

        """

        Convert the polygon data received from Spatialite to min/max values.

        """

        backend = connections[self.db].ops

        if not backend.geojson:

            raise NotImplementedError('Only PostGIS 1.3.4+ and SpatiaLite 3.0+ '

                                      'support GeoJSON serialization.')

            raise NotImplementedError('Only PostGIS and SpatiaLite support GeoJSON serialization.')

        if not isinstance(precision, six.integer_types):

            raise TypeError('Precision keyword must be set with an integer.')

=======================  =======  ======  ==========

Aggregate                PostGIS  Oracle  SpatiaLite

=======================  =======  ======  ==========

:class:`Collect`         X                (from v3.0)

:class:`Extent`          X        X       (from v3.0)

:class:`Collect`         X                X

:class:`Extent`          X        X       X

:class:`Extent3D`        X

:class:`MakeLine`        X

:class:`Union`           X        X       X

.. class:: Collect(geo_field)

*Availability*: PostGIS, Spatialite (≥3.0)

*Availability*: PostGIS, Spatialite

Returns a ``GEOMETRYCOLLECTION`` or a ``MULTI`` geometry object from the geometry

column. This is analogous to a simplified version of the :class:`Union`

.. class:: Extent(geo_field)

*Availability*: PostGIS, Oracle, Spatialite (≥3.0)

*Availability*: PostGIS, Oracle, Spatialite

Returns the extent of all ``geo_field`` in the ``QuerySet`` as a four-tuple,

comprising the lower left coordinate and the upper right coordinate.

:doc:`GDAL <../gdal>`     Geospatial Data Abstraction Library   Yes (SQLite only)                 2.0, 1.11, 1.10, 1.9, 1.8, 1.7

:doc:`GeoIP <../geoip>`   IP-based geolocation library          No                                1.4

`PostGIS`__               Spatial extensions for PostgreSQL     Yes (PostgreSQL only)             2.1, 2.0

`SpatiaLite`__            Spatial extensions for SQLite         Yes (SQLite only)                 4.1, 4.0, 3.0, 2.4

`SpatiaLite`__            Spatial extensions for SQLite         Yes (SQLite only)                 4.1, 4.0, 3.0

========================  ====================================  ================================  ============================

Note that older or more recent versions of these libraries *may* also work

    GDAL 1.11.0 2014-04-25

    PostGIS 2.0.0 2012-04-03

    PostGIS 2.1.0 2013-08-17

    Spatialite 2.4.0 2010-11-14

    Spatialite 3.0.0 2011-12-30

    Spatialite 4.0.0 2012-11-25

    Spatialite 4.1.0 2013-06-04