from __future__ import annotations

from datetime import datetime
from uuid import UUID, uuid4

import pytest

from schemas.enums import NotificationTargetMode
from v1.notifications.service import NotificationService


class _FakeNotification:
    def __init__(
        self,
        *,
        id: UUID,
        target_mode: NotificationTargetMode = NotificationTargetMode.ALL_USERS,
        status: str = "published",
        deleted_at: datetime | None = None,
    ):
        self.id = id
        self.target_mode = target_mode
        self.status = status
        self.deleted_at = deleted_at


class _TrackingNotificationRepository:
    def __init__(self, notifications: list[_FakeNotification]) -> None:
        self._notifications = notifications
        self.linked_notification_ids: list[list[UUID]] = []
        self.linked_is_first: list[bool] = []

    async def link_notifications_for_registered_user(
        self, *, user_id: UUID, is_first_registration: bool
    ) -> int:
        target_modes: list[NotificationTargetMode]
        if is_first_registration:
            target_modes = [
                NotificationTargetMode.NEW_USERS,
                NotificationTargetMode.ALL_USERS,
            ]
        else:
            target_modes = [NotificationTargetMode.ALL_USERS]

        matched = [
            n
            for n in self._notifications
            if n.status == "published"
            and n.deleted_at is None
            and n.target_mode in target_modes
        ]
        self.linked_notification_ids.append([n.id for n in matched])
        self.linked_is_first.append(is_first_registration)
        return len(matched)


@pytest.fixture
def notification_new_users() -> _FakeNotification:
    return _FakeNotification(id=uuid4(), target_mode=NotificationTargetMode.NEW_USERS)


@pytest.fixture
def notification_all_users() -> _FakeNotification:
    return _FakeNotification(id=uuid4(), target_mode=NotificationTargetMode.ALL_USERS)


@pytest.fixture
def notification_exist_users() -> _FakeNotification:
    return _FakeNotification(id=uuid4(), target_mode=NotificationTargetMode.EXIST_USERS)


class TestLinkNotificationsForRegisteredUser:
    @pytest.mark.asyncio
    async def test_first_registration_gets_new_users_and_all_users(
        self,
        notification_new_users: _FakeNotification,
        notification_all_users: _FakeNotification,
        notification_exist_users: _FakeNotification,
    ) -> None:
        repo = _TrackingNotificationRepository(
            [notification_new_users, notification_all_users, notification_exist_users]
        )
        service = NotificationService(repository=repo)  # type: ignore[arg-type]

        count = await service.link_notifications_for_registered_user(
            user_id=uuid4(), is_first_registration=True
        )

        assert count == 2
        linked_ids = repo.linked_notification_ids[0]
        assert notification_new_users.id in linked_ids
        assert notification_all_users.id in linked_ids
        assert notification_exist_users.id not in linked_ids

    @pytest.mark.asyncio
    async def test_reregistered_user_only_gets_all_users(
        self,
        notification_new_users: _FakeNotification,
        notification_all_users: _FakeNotification,
        notification_exist_users: _FakeNotification,
    ) -> None:
        repo = _TrackingNotificationRepository(
            [notification_new_users, notification_all_users, notification_exist_users]
        )
        service = NotificationService(repository=repo)  # type: ignore[arg-type]

        count = await service.link_notifications_for_registered_user(
            user_id=uuid4(), is_first_registration=False
        )

        assert count == 1
        linked_ids = repo.linked_notification_ids[0]
        assert notification_new_users.id not in linked_ids
        assert notification_all_users.id in linked_ids
        assert notification_exist_users.id not in linked_ids

    @pytest.mark.asyncio
    async def test_no_published_notifications_returns_zero(self) -> None:
        repo = _TrackingNotificationRepository([])
        service = NotificationService(repository=repo)  # type: ignore[arg-type]

        count = await service.link_notifications_for_registered_user(
            user_id=uuid4(), is_first_registration=True
        )

        assert count == 0

    @pytest.mark.asyncio
    async def test_only_new_users_notification_first_registration(self) -> None:
        n = _FakeNotification(id=uuid4(), target_mode=NotificationTargetMode.NEW_USERS)
        repo = _TrackingNotificationRepository([n])
        service = NotificationService(repository=repo)  # type: ignore[arg-type]

        count = await service.link_notifications_for_registered_user(
            user_id=uuid4(), is_first_registration=True
        )

        assert count == 1

    @pytest.mark.asyncio
    async def test_only_new_users_notification_reregistered(self) -> None:
        n = _FakeNotification(id=uuid4(), target_mode=NotificationTargetMode.NEW_USERS)
        repo = _TrackingNotificationRepository([n])
        service = NotificationService(repository=repo)  # type: ignore[arg-type]

        count = await service.link_notifications_for_registered_user(
            user_id=uuid4(), is_first_registration=False
        )

        assert count == 0