from typing import Annotated

from fastapi import Depends, HTTPException, status
from fastapi.security import OAuth2PasswordBearer
from jose import JWTError, jwt
from sqlmodel import Session, select

from app.core.config import get_settings
from app.database import get_session
from app.models import User
from app.schemas import TokenData

settings = get_settings()
oauth2_scheme = OAuth2PasswordBearer(tokenUrl="/api/auth/token")

SessionDep = Annotated[Session, Depends(get_session)]


def get_current_user(
    session: SessionDep,
    token: Annotated[str, Depends(oauth2_scheme)],
) -> User:
    credentials_exception = HTTPException(
        status_code=status.HTTP_401_UNAUTHORIZED,
        detail="Could not validate credentials",
        headers={"WWW-Authenticate": "Bearer"},
    )
    try:
        payload = jwt.decode(token, settings.secret_key, algorithms=[settings.algorithm])
        username = payload.get("sub")
        if username is None:
            raise credentials_exception
        token_data = TokenData(username=username)
    except JWTError:
        raise credentials_exception

    user = session.exec(select(User).where(User.username == token_data.username)).first()
    if user is None:
        raise credentials_exception
    return user


CurrentUserDep = Annotated[User, Depends(get_current_user)]