"""Shared path resolution for thread virtual paths (e.g. mnt/user-data/outputs/...)."""

from pathlib import Path

from fastapi import HTTPException

from deerflow.config.paths import get_paths
from deerflow.runtime.thread_paths import aresolve_path_user_id, resolve_path_user_id


def resolve_thread_virtual_path(thread_id: str, virtual_path: str, *, user_id: str | None = None) -> Path:
    """Resolve a virtual path to the actual filesystem path under thread user-data.

    Args:
        thread_id: The thread ID.
        virtual_path: The virtual path as seen inside the sandbox
                      (e.g., /mnt/user-data/outputs/file.txt).
        user_id: Pre-resolved canonical user bucket. When ``None`` it is
                 resolved synchronously via :func:`resolve_path_user_id` (the
                 thread creator for task-shared threads, else the current
                 login). Async callers should pass the result of
                 :func:`aresolve_path_user_id` to avoid a blocking DB read.

    Returns:
        The resolved filesystem path.

    Raises:
        HTTPException: If the path is invalid or outside allowed directories.
    """
    if user_id is None:
        user_id = resolve_path_user_id(thread_id)
    try:
        return get_paths().resolve_virtual_path(thread_id, virtual_path, user_id=user_id)
    except ValueError as e:
        status = 403 if "traversal" in str(e) else 400
        raise HTTPException(status_code=status, detail=str(e))


async def aresolve_thread_virtual_path(thread_id: str, virtual_path: str) -> Path:
    """Async variant of :func:`resolve_thread_virtual_path` for FastAPI handlers.

    Resolves the canonical user bucket without blocking the event loop, so a
    task-shared thread's artifacts resolve to the thread creator's directory
    regardless of which account is currently logged in.
    """
    user_id = await aresolve_path_user_id(thread_id)
    return resolve_thread_virtual_path(thread_id, virtual_path, user_id=user_id)