from django.contrib.gis.db.models import Collect, Count, Extent, F, Union
from django.contrib.gis.geos import GEOSGeometry, MultiPoint, Point
from django.db import NotSupportedError, connection
from django.test import TestCase, skipUnlessDBFeature
from django.test.utils import override_settings
from django.utils import timezone

from .models import (
    Article, Author, Book, City, DirectoryEntry, Event, Location, Parcel,
)


class RelatedGeoModelTest(TestCase):
    fixtures = ['initial']

    def test02_select_related(self):
        "Testing `select_related` on geographic models (see #7126)."
        qs1 = City.objects.order_by('id')
        qs2 = City.objects.order_by('id').select_related()
        qs3 = City.objects.order_by('id').select_related('location')

        # Reference data for what's in the fixtures.
        cities = (
            ('Aurora', 'TX', -97.516111, 33.058333),
            ('Roswell', 'NM', -104.528056, 33.387222),
            ('Kecksburg', 'PA', -79.460734, 40.18476),
        )

        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.assertAlmostEqual(lon, c.location.point.x, 6)
                self.assertAlmostEqual(lat, c.location.point.y, 6)

    @skipUnlessDBFeature("supports_extent_aggr")
    def test_related_extent_aggregate(self):
        "Testing the `Extent` aggregate on related geographic models."
        # This combines the Extent and Union aggregates into one query
        aggs = City.objects.aggregate(Extent('location__point'))

        # One for all locations, one that excludes New Mexico (Roswell).
        all_extent = (-104.528056, 29.763374, -79.460734, 40.18476)
        txpa_extent = (-97.516111, 29.763374, -79.460734, 40.18476)
        e1 = City.objects.aggregate(Extent('location__point'))['location__point__extent']
        e2 = City.objects.exclude(state='NM').aggregate(Extent('location__point'))['location__point__extent']
        e3 = aggs['location__point__extent']

        # The tolerance value is to four decimal places because of differences
        # between the Oracle and PostGIS spatial backends on the extent calculation.
        tol = 4
        for ref, e in [(all_extent, e1), (txpa_extent, e2), (all_extent, e3)]:
            for ref_val, e_val in zip(ref, e):
                self.assertAlmostEqual(ref_val, e_val, tol)

    @skipUnlessDBFeature("supports_extent_aggr")
    def test_related_extent_annotate(self):
        """
        Test annotation with Extent GeoAggregate.
        """
        cities = City.objects.annotate(points_extent=Extent('location__point')).order_by('name')
        tol = 4
        self.assertAlmostEqual(
            cities[0].points_extent,
            (-97.516111, 33.058333, -97.516111, 33.058333),
            tol
        )

    @skipUnlessDBFeature('supports_union_aggr')
    def test_related_union_aggregate(self):
        "Testing the `Union` aggregate on related geographic models."
        # This combines the Extent and Union aggregates into one query
        aggs = City.objects.aggregate(Union('location__point'))

        # These are the points that are components of the aggregate geographic
        # union that is returned.  Each point # corresponds to City PK.
        p1 = Point(-104.528056, 33.387222)
        p2 = Point(-97.516111, 33.058333)
        p3 = Point(-79.460734, 40.18476)
        p4 = Point(-96.801611, 32.782057)
        p5 = Point(-95.363151, 29.763374)

        # The second union aggregate is for a union
        # query that includes limiting information in the WHERE clause (in other
        # words a `.filter()` precedes the call to `.aggregate(Union()`).
        ref_u1 = MultiPoint(p1, p2, p4, p5, p3, srid=4326)
        ref_u2 = MultiPoint(p2, p3, srid=4326)

        u1 = City.objects.aggregate(Union('location__point'))['location__point__union']
        u2 = City.objects.exclude(
            name__in=('Roswell', 'Houston', 'Dallas', 'Fort Worth'),
        ).aggregate(Union('location__point'))['location__point__union']
        u3 = aggs['location__point__union']
        self.assertEqual(type(u1), MultiPoint)
        self.assertEqual(type(u3), MultiPoint)

        # Ordering of points in the result of the union is not defined and
        # implementation-dependent (DB backend, GEOS version)
        self.assertEqual({p.ewkt for p in ref_u1}, {p.ewkt for p in u1})
        self.assertEqual({p.ewkt for p in ref_u2}, {p.ewkt for p in u2})
        self.assertEqual({p.ewkt for p in ref_u1}, {p.ewkt for p in u3})

    def test05_select_related_fk_to_subclass(self):
        "Testing that calling select_related on a query over a model with an FK to a model subclass works"
        # Regression test for #9752.
        list(DirectoryEntry.objects.all().select_related())

    def test06_f_expressions(self):
        "Testing F() expressions on GeometryFields."
        # Constructing a dummy parcel border and getting the City instance for
        # assigning the FK.
        b1 = GEOSGeometry(
            'POLYGON((-97.501205 33.052520,-97.501205 33.052576,'
            '-97.501150 33.052576,-97.501150 33.052520,-97.501205 33.052520))',
            srid=4326
        )
        pcity = City.objects.get(name='Aurora')

        # First parcel has incorrect center point that is equal to the City;
        # it also has a second border that is different from the first as a
        # 100ft buffer around the City.
        c1 = pcity.location.point
        c2 = c1.transform(2276, clone=True)
        b2 = c2.buffer(100)
        Parcel.objects.create(name='P1', city=pcity, center1=c1, center2=c2, border1=b1, border2=b2)

        # Now creating a second Parcel where the borders are the same, just
        # in different coordinate systems.  The center points are also the
        # same (but in different coordinate systems), and this time they
        # actually correspond to the centroid of the border.
        c1 = b1.centroid
        c2 = c1.transform(2276, clone=True)
        b2 = b1 if connection.features.supports_transform else b1.transform(2276, clone=True)
        Parcel.objects.create(name='P2', city=pcity, center1=c1, center2=c2, border1=b1, border2=b2)

        # Should return the second Parcel, which has the center within the
        # border.
        qs = Parcel.objects.filter(center1__within=F('border1'))
        self.assertEqual(1, len(qs))
        self.assertEqual('P2', qs[0].name)

        # This time center2 is in a different coordinate system and needs to be
        # wrapped in transformation SQL.
        qs = Parcel.objects.filter(center2__within=F('border1'))
        if connection.features.supports_transform:
            self.assertEqual('P2', qs.get().name)
        else:
            msg = "This backend doesn't support the Transform function."
            with self.assertRaisesMessage(NotSupportedError, msg):
                list(qs)

        # Should return the first Parcel, which has the center point equal
        # to the point in the City ForeignKey.
        qs = Parcel.objects.filter(center1=F('city__location__point'))
        self.assertEqual(1, len(qs))
        self.assertEqual('P1', qs[0].name)

        # This time the city column should be wrapped in transformation SQL.
        qs = Parcel.objects.filter(border2__contains=F('city__location__point'))
        if connection.features.supports_transform:
            self.assertEqual('P1', qs.get().name)
        else:
            msg = "This backend doesn't support the Transform function."
            with self.assertRaisesMessage(NotSupportedError, msg):
                list(qs)

    def test07_values(self):
        "Testing values() and values_list()."
        gqs = Location.objects.all()
        gvqs = Location.objects.values()
        gvlqs = Location.objects.values_list()

        # Incrementing through each of the models, dictionaries, and tuples
        # returned by each QuerySet.
        for m, d, t in zip(gqs, gvqs, gvlqs):
            # The values should be Geometry objects and not raw strings returned
            # by the spatial database.
            self.assertIsInstance(d['point'], GEOSGeometry)
            self.assertIsInstance(t[1], GEOSGeometry)
            self.assertEqual(m.point, d['point'])
            self.assertEqual(m.point, t[1])

    @override_settings(USE_TZ=True)
    def test_07b_values(self):
        "Testing values() and values_list() with aware datetime. See #21565."
        Event.objects.create(name="foo", when=timezone.now())
        list(Event.objects.values_list('when'))

    def test08_defer_only(self):
        "Testing defer() and only() on Geographic models."
        qs = Location.objects.all().order_by("pk")
        def_qs = Location.objects.defer("point").order_by("pk")
        for loc, def_loc in zip(qs, def_qs):
            self.assertEqual(loc.point, def_loc.point)

    def test09_pk_relations(self):
        "Ensuring correct primary key column is selected across relations. See #10757."
        # The expected ID values -- notice the last two location IDs
        # are out of order.  Dallas and Houston have location IDs that differ
        # from their PKs -- this is done to ensure that the related location
        # ID column is selected instead of ID column for the city.
        city_ids = (1, 2, 3, 4, 5)
        loc_ids = (1, 2, 3, 5, 4)
        ids_qs = City.objects.order_by('id').values('id', 'location__id')
        for val_dict, c_id, l_id in zip(ids_qs, city_ids, loc_ids):
            self.assertEqual(val_dict['id'], c_id)
            self.assertEqual(val_dict['location__id'], l_id)

    def test10_combine(self):
        "Testing the combination of two QuerySets (#10807)."
        buf1 = City.objects.get(name='Aurora').location.point.buffer(0.1)
        buf2 = City.objects.get(name='Kecksburg').location.point.buffer(0.1)
        qs1 = City.objects.filter(location__point__within=buf1)
        qs2 = City.objects.filter(location__point__within=buf2)
        combined = qs1 | qs2
        names = [c.name for c in combined]
        self.assertEqual(2, len(names))
        self.assertIn('Aurora', names)
        self.assertIn('Kecksburg', names)

    @skipUnlessDBFeature('allows_group_by_lob')
    def test12a_count(self):
        "Testing `Count` aggregate on geo-fields."
        # The City, 'Fort Worth' uses the same location as Dallas.
        dallas = City.objects.get(name='Dallas')

        # Count annotation should be 2 for the Dallas location now.
        loc = Location.objects.annotate(num_cities=Count('city')).get(id=dallas.location.id)
        self.assertEqual(2, loc.num_cities)

    def test12b_count(self):
        "Testing `Count` aggregate on non geo-fields."
        # Should only be one author (Trevor Paglen) returned by this query, and
        # the annotation should have 3 for the number of books, see #11087.
        # Also testing with a values(), see #11489.
        qs = Author.objects.annotate(num_books=Count('books')).filter(num_books__gt=1)
        vqs = Author.objects.values('name').annotate(num_books=Count('books')).filter(num_books__gt=1)
        self.assertEqual(1, len(qs))
        self.assertEqual(3, qs[0].num_books)
        self.assertEqual(1, len(vqs))
        self.assertEqual(3, vqs[0]['num_books'])

    @skipUnlessDBFeature('allows_group_by_lob')
    def test13c_count(self):
        "Testing `Count` aggregate with `.values()`.  See #15305."
        qs = Location.objects.filter(id=5).annotate(num_cities=Count('city')).values('id', 'point', 'num_cities')
        self.assertEqual(1, len(qs))
        self.assertEqual(2, qs[0]['num_cities'])
        self.assertIsInstance(qs[0]['point'], GEOSGeometry)

    def test13_select_related_null_fk(self):
        "Testing `select_related` on a nullable ForeignKey."
        Book.objects.create(title='Without Author')
        b = Book.objects.select_related('author').get(title='Without Author')
        # Should be `None`, and not a 'dummy' model.
        self.assertIsNone(b.author)

    @skipUnlessDBFeature("supports_collect_aggr")
    def test_collect(self):
        """
        Testing the `Collect` aggregate.
        """
        # Reference query:
        # SELECT AsText(ST_Collect("relatedapp_location"."point")) FROM "relatedapp_city" LEFT OUTER JOIN
        #    "relatedapp_location" ON ("relatedapp_city"."location_id" = "relatedapp_location"."id")
        #    WHERE "relatedapp_city"."state" = 'TX';
        ref_geom = GEOSGeometry(
            'MULTIPOINT(-97.516111 33.058333,-96.801611 32.782057,'
            '-95.363151 29.763374,-96.801611 32.782057)'
        )

        coll = City.objects.filter(state='TX').aggregate(Collect('location__point'))['location__point__collect']
        # Even though Dallas and Ft. Worth share same point, Collect doesn't
        # consolidate -- that's why 4 points in MultiPoint.
        self.assertEqual(4, len(coll))
        self.assertTrue(ref_geom.equals(coll))

    def test15_invalid_select_related(self):
        "Testing doing select_related on the related name manager of a unique FK. See #13934."
        qs = Article.objects.select_related('author__article')
        # This triggers TypeError when `get_default_columns` has no `local_only`
        # keyword.  The TypeError is swallowed if QuerySet is actually
        # evaluated as list generation swallows TypeError in CPython.
        str(qs.query)

    def test16_annotated_date_queryset(self):
        "Ensure annotated date querysets work if spatial backend is used.  See #14648."
        birth_years = [dt.year for dt in
                       list(Author.objects.annotate(num_books=Count('books')).dates('dob', 'year'))]
        birth_years.sort()
        self.assertEqual([1950, 1974], birth_years)

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