from datetime import timedelta
from io import StringIO

from django.contrib.auth import get_user_model
from django.core.management import call_command
from django.test import TestCase
from django.utils import timezone

from misago.categories.models import Category
from misago.conf import settings
from misago.readtracker.management.commands import clearreadtracker
from misago.readtracker.models import PostRead
from misago.threads import testutils


UserModel = get_user_model()


class ClearReadTrackerTests(TestCase):
    def setUp(self):
        self.user_a = UserModel.objects.create_user(
            "UserA", "testa@user.com", "Pass.123"
        )
        self.user_b = UserModel.objects.create_user(
            "UserB", "testb@user.com", "Pass.123"
        )

        self.category = Category.objects.get(slug="first-category")

    def test_no_deleted(self):
        """command works when there are no attachments"""
        command = clearreadtracker.Command()

        out = StringIO()
        call_command(command, stdout=out)
        command_output = out.getvalue().strip()

        self.assertEqual(command_output, "No expired entries were found")

    def test_delete_expired_entries(self):
        """test deletes one expired tracker entry, but spares the other"""
        thread = testutils.post_thread(self.category)

        existing = PostRead.objects.create(
            user=self.user_a,
            category=self.category,
            thread=thread,
            post=thread.first_post,
            last_read_on=timezone.now()
            - timedelta(days=settings.MISAGO_READTRACKER_CUTOFF / 4),
        )
        deleted = PostRead.objects.create(
            user=self.user_b,
            category=self.category,
            thread=thread,
            post=thread.first_post,
            last_read_on=timezone.now()
            - timedelta(days=settings.MISAGO_READTRACKER_CUTOFF * 2),
        )

        command = clearreadtracker.Command()

        out = StringIO()
        call_command(command, stdout=out)
        command_output = out.getvalue().strip()

        self.assertEqual(command_output, "Deleted 1 expired entries")

        PostRead.objects.get(pk=existing.pk)
        with self.assertRaises(PostRead.DoesNotExist):
            PostRead.objects.get(pk=deleted.pk)