import django
import pytest

from django.db import models

from psqlextra.fields import HStoreField
from psqlextra.query import ConflictAction

from .fake_model import get_fake_model


def test_on_conflict_update():
    """Tests whether simple upserts works correctly."""

    model = get_fake_model(
        {
            "title": HStoreField(uniqueness=["key1"]),
            "cookies": models.CharField(max_length=255, null=True),
        }
    )

    obj1 = model.objects.on_conflict(
        [("title", "key1")], ConflictAction.UPDATE
    ).insert_and_get(title={"key1": "beer"}, cookies="cheers")

    obj1.refresh_from_db()
    assert obj1.title["key1"] == "beer"
    assert obj1.cookies == "cheers"

    obj2 = model.objects.on_conflict(
        [("title", "key1")], ConflictAction.UPDATE
    ).insert_and_get(title={"key1": "beer"}, cookies="choco")

    obj1.refresh_from_db()
    obj2.refresh_from_db()

    # assert both objects are the same
    assert obj1.id == obj2.id
    assert obj1.title["key1"] == "beer"
    assert obj1.cookies == "choco"
    assert obj2.title["key1"] == "beer"
    assert obj2.cookies == "choco"


@pytest.mark.skipif(
    django.VERSION < (2, 2),
    reason="Django < 2.2 doesn't implement constraints",
)
def test_on_conflict_update_by_unique_constraint():
    model = get_fake_model(
        {
            "title": models.CharField(max_length=255, null=True),
        },
        meta_options={
            "constraints": [
                models.UniqueConstraint(name="test_uniq", fields=["title"]),
            ],
        },
    )

    constraint = next(
        (
            constraint
            for constraint in model._meta.constraints
            if constraint.name == "test_uniq"
        )
    )

    model.objects.on_conflict(constraint, ConflictAction.UPDATE).insert_and_get(
        title="title"
    )


def test_on_conflict_update_foreign_key_by_object():
    """Tests whether simple upsert works correctly when the conflicting field
    is a foreign key specified as an object."""

    other_model = get_fake_model({})

    model = get_fake_model(
        {
            "other": models.OneToOneField(
                other_model, on_delete=models.CASCADE
            ),
            "data": models.CharField(max_length=255),
        }
    )

    other_obj = other_model.objects.create()

    obj1 = model.objects.on_conflict(
        ["other"], ConflictAction.UPDATE
    ).insert_and_get(other=other_obj, data="some data")

    assert obj1.other == other_obj
    assert obj1.data == "some data"

    obj1.refresh_from_db()
    assert obj1.other == other_obj
    assert obj1.data == "some data"

    with pytest.raises(ValueError):
        (
            model.objects.on_conflict(
                ["other"], ConflictAction.UPDATE
            ).insert_and_get(other=obj1)
        )

    obj2 = model.objects.on_conflict(
        ["other"], ConflictAction.UPDATE
    ).insert_and_get(other=other_obj, data="different data")

    assert obj2.other == other_obj
    assert obj2.data == "different data"

    obj1.refresh_from_db()
    obj2.refresh_from_db()

    # assert that the 'other' field didn't change
    assert obj1.id == obj2.id
    assert obj1.other == other_obj
    assert obj2.other == other_obj
    assert obj1.data == "different data"
    assert obj2.data == "different data"


def test_on_conflict_update_foreign_key_by_id():
    """Tests whether simple upsert works correctly when the conflicting field
    is a foreign key specified as an id."""

    other_model = get_fake_model({})

    model = get_fake_model(
        {
            "other": models.OneToOneField(
                other_model, on_delete=models.CASCADE
            ),
            "data": models.CharField(max_length=255),
        }
    )

    other_obj = other_model.objects.create()

    obj1 = model.objects.on_conflict(
        ["other_id"], ConflictAction.UPDATE
    ).insert_and_get(other_id=other_obj.pk, data="some data")

    assert obj1.other == other_obj
    assert obj1.data == "some data"

    obj1.refresh_from_db()
    assert obj1.other == other_obj
    assert obj1.data == "some data"

    obj2 = model.objects.on_conflict(
        ["other_id"], ConflictAction.UPDATE
    ).insert_and_get(other_id=other_obj.pk, data="different data")

    assert obj2.other == other_obj
    assert obj2.data == "different data"

    obj1.refresh_from_db()
    obj2.refresh_from_db()

    # assert that the 'other' field didn't change
    assert obj1.id == obj2.id
    assert obj1.other == other_obj
    assert obj2.other == other_obj
    assert obj1.data == "different data"
    assert obj2.data == "different data"