"""Safe compact task badges shown on resources linked to tasks."""

from collections.abc import Iterable

from django.contrib.contenttypes.models import ContentType

from tasks.access import task_board_access_q
from tasks.models import TaskBoard, TaskLinkedObject


def accessible_task_board_ids(user) -> set[int]:
    if not user or not getattr(user, "is_authenticated", False):
        return set()
    return set(
        TaskBoard.objects.filter(is_archived=False)
        .filter(task_board_access_q(user))
        .values_list("id", flat=True)
        .distinct()
    )


def linked_task_badge_payload(
    link: TaskLinkedObject,
    *,
    accessible_board_ids: set[int],
    include_task_card_fields: bool = False,
) -> dict:
    task = link.task
    can_open = task.board_id in accessible_board_ids
    payload = {
        "link_id": link.id,
        "id": task.id,
        "title": task.title,
        "board_id": task.board_id,
        "board_name": task.board.name,
        "column_id": task.column_id,
        "column_name": task.column.name,
        "column_color": task.column.color,
        "priority": task.priority,
        "priority_display": task.get_priority_display(),
        "can_open": can_open,
    }
    if include_task_card_fields:
        # Linked-task management screens historically consume a TaskCard-like
        # shape. Keep these aliases without exposing the full task serializer.
        payload.update(board=task.board_id, column=task.column_id)
    return payload


def linked_task_badges_by_object(
    *,
    model,
    kind: str,
    object_ids: Iterable[int],
    user,
    include_task_card_fields: bool = False,
) -> dict[int, list[dict]]:
    ids = list(dict.fromkeys(object_ids))
    mapping = {object_id: [] for object_id in ids}
    if not ids or not user or not getattr(user, "is_authenticated", False):
        return mapping

    content_type = ContentType.objects.get_for_model(model)
    board_ids = accessible_task_board_ids(user)
    links = (
        TaskLinkedObject.objects.filter(
            kind=kind,
            content_type=content_type,
            object_id__in=ids,
        )
        .select_related("task", "task__board", "task__column")
        .order_by("object_id", "task__title", "task_id")
    )
    for link in links:
        mapping.setdefault(link.object_id, []).append(
            linked_task_badge_payload(
                link,
                accessible_board_ids=board_ids,
                include_task_card_fields=include_task_card_fields,
            )
        )
    return mapping


def linked_task_badges_for_object(
    *,
    obj,
    kind: str,
    user,
    include_task_card_fields: bool = False,
) -> list[dict]:
    return linked_task_badges_by_object(
        model=obj.__class__,
        kind=kind,
        object_ids=[obj.id],
        user=user,
        include_task_card_fields=include_task_card_fields,
    ).get(obj.id, [])