"""Shared API dependencies."""

import uuid
from typing import Annotated

from fastapi import Depends, Header, HTTPException, status
from sqlalchemy.ext.asyncio import AsyncSession

from app.core.db import get_session
from app.models.user import User
from app.services.user_service import get_user

SessionDep = Annotated[AsyncSession, Depends(get_session)]


async def get_current_user(
    session: SessionDep,
    x_user_id: Annotated[uuid.UUID | None, Header()] = None,
) -> User:
    """TEMPORARY pre-auth shim: identifies the caller via the ``X-User-Id``
    header. Replaced by the AuthProvider (sessions/tokens) in the auth slice.
    The assistant principal will also be minted here, scoped to its user."""
    if x_user_id is None:
        raise HTTPException(
            status.HTTP_401_UNAUTHORIZED, "X-User-Id header required (pre-auth)"
        )
    user = await get_user(session, x_user_id)
    if user is None:
        raise HTTPException(status.HTTP_401_UNAUTHORIZED, "unknown user")
    return user


CurrentUser = Annotated[User, Depends(get_current_user)]