"""Utilities for dataloader endpoints."""

from typing import TypeVar

from ddtrace import tracer

T = TypeVar('T')


@tracer.wrap('utils.format_for_dataloader')
def format_for_dataloader(
    items: list[T],
    keys: list[str],
    lookup_key: str,
) -> list[T | None]:
    """Format results for dataloader pattern, maintaining order and handling missing items.

    Args:
        items: List of objects with the lookup_key attribute.
        keys: List of keys to order the items by.
        lookup_key: The attribute name to use for matching against keys.

    Returns:
        List of items ordered by keys, with None for missing items.
    """
    items_dict = {str(getattr(item, lookup_key, None)): item for item in items}
    return [items_dict.get(str(key)) for key in keys]