from fastapi import Depends, HTTPException, status
from fastapi.security import HTTPBearer, HTTPAuthorizationCredentials
from jose import JWTError, jwt
from app.core.config import settings
from app.db.session import get_db
from app.models.schemas import User
from motor.motor_asyncio import AsyncIOMotorDatabase

security = HTTPBearer()

async def get_current_user(
    db: AsyncIOMotorDatabase = Depends(get_db),
    credentials: HTTPAuthorizationCredentials = Depends(security)
) -> User:
    credentials_exception = HTTPException(
        status_code=status.HTTP_401_UNAUTHORIZED,
        detail="Could not validate credentials",
        headers={"WWW-Authenticate": "Bearer"},
    )
    try:
        payload = jwt.decode(credentials.credentials, settings.SECRET_KEY, algorithms=[settings.ALGORITHM])
        user_id: str = payload.get("sub")
        if user_id is None:
            raise credentials_exception
        
        user_data = await db.users.find_one({"id": user_id})
        if user_data is None:
            raise credentials_exception
            
        return User(**user_data)
    except JWTError:
        raise credentials_exception