import os, unittest

from django.contrib.gis.geos import *

from django.contrib.gis.tests.utils import no_mysql, postgis

from django.conf import settings

from models import City, Location

cities = (('Aurora', 'TX', -97.516111, 33.058333),

          ('Roswell', 'NM', -104.528056, 33.387222),

          ('Kecksburg', 'PA',  -79.460734, 40.18476),

           )

class RelatedGeoModelTest(unittest.TestCase):

    def test01_setup(self):

        "Setting up for related model tests."

        for name, state, lon, lat in cities:

            loc = Location(point=Point(lon, lat))

            loc.save()

            c = City(name=name, state=state, location=loc)

            c.save()

    def test02_select_related(self):

        "Testing `select_related` on geographic models (see #7126)."

        qs1 = City.objects.all()

        qs2 = City.objects.select_related()

        qs3 = City.objects.select_related('location')

        for qs in (qs1, qs2, qs3):

            for ref, c in zip(cities, qs):

                nm, st, lon, lat = ref

                self.assertEqual(nm, c.name)

                self.assertEqual(st, c.state)

                self.assertEqual(Point(lon, lat), c.location.point)

    @no_mysql

    def test03_transform_related(self):

        "Testing the `transform` GeoQuerySet method on related geographic models."

        # All the transformations are to state plane coordinate systems using

        # US Survey Feet (thus a tolerance of 0 implies error w/in 1 survey foot).

        if postgis:

            tol = 3

            nqueries = 4 # +1 for `postgis_lib_version`

        else:

            tol = 0

            nqueries = 3

        def check_pnt(ref, pnt):

            self.assertAlmostEqual(ref.x, pnt.x, tol)

            self.assertAlmostEqual(ref.y, pnt.y, tol)

            self.assertEqual(ref.srid, pnt.srid)

        # Turning on debug so we can manually verify the number of SQL queries issued.

        # DISABLED: the number of queries count testing mechanism is way too brittle.

        #dbg = settings.DEBUG

        #settings.DEBUG = True

        from django.db import connection

        # Each city transformed to the SRID of their state plane coordinate system.

        transformed = (('Kecksburg', 2272, 'POINT(1490553.98959621 314792.131023984)'),

                       ('Roswell', 2257, 'POINT(481902.189077221 868477.766629735)'),

                       ('Aurora', 2276, 'POINT(2269923.2484839 7069381.28722222)'),

                       )

        for name, srid, wkt in transformed:

            # Doing this implicitly sets `select_related` select the location.

            qs = list(City.objects.filter(name=name).transform(srid, field_name='location__point'))

            check_pnt(GEOSGeometry(wkt, srid), qs[0].location.point) 

        #settings.DEBUG= dbg

        # Verifying the number of issued SQL queries.

        #self.assertEqual(nqueries, len(connection.queries))

    @no_mysql

    def test04_related_aggregate(self):

        "Testing the `extent` and `unionagg` GeoQuerySet aggregates on related geographic models."

        if postgis:

            # One for all locations, one that excludes Roswell.

            all_extent = (-104.528060913086, 33.0583305358887,-79.4607315063477, 40.1847610473633)

            txpa_extent = (-97.51611328125, 33.0583305358887,-79.4607315063477, 40.1847610473633)

            e1 = City.objects.extent(field_name='location__point')

            e2 = City.objects.exclude(name='Roswell').extent(field_name='location__point')

            for ref, e in [(all_extent, e1), (txpa_extent, e2)]:

                for ref_val, e_val in zip(ref, e): self.assertAlmostEqual(ref_val, e_val)

        # The second union is for a query that has something in the WHERE clause.

        ref_u1 = GEOSGeometry('MULTIPOINT(-104.528056 33.387222,-97.516111 33.058333,-79.460734 40.18476)', 4326)

        ref_u2 = GEOSGeometry('MULTIPOINT(-97.516111 33.058333,-79.460734 40.18476)', 4326)

        u1 = City.objects.unionagg(field_name='location__point')

        u2 = City.objects.exclude(name='Roswell').unionagg(field_name='location__point')

        self.assertEqual(ref_u1, u1)

        self.assertEqual(ref_u2, u2)

    # TODO: Related tests for KML, GML, and distance lookups.

def suite():

    s = unittest.TestSuite()

    s.addTest(unittest.makeSuite(RelatedGeoModelTest))

    return s