from fastapi import Depends, HTTPException, status
from fastapi.security import HTTPBearer, HTTPAuthorizationCredentials
from jose import jwt, JWTError
from sqlalchemy.orm import Session
from app.db.session import get_db
from app.core.security import SECRET_KEY, ALGORITHM
from app.models.user import User

security = HTTPBearer()

def get_current_user(
    db: Session = 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, SECRET_KEY, algorithms=[ALGORITHM])
        user_id: str = payload.get("sub")
        if user_id is None:
            raise credentials_exception
    except JWTError:
        raise credentials_exception
    
    user = db.query(User).filter(User.id == int(user_id)).first()
    if user is None:
        raise credentials_exception
    return user

def get_current_active_user(
    current_user: User = Depends(get_current_user),
) -> User:
    if not current_user.is_active:
        raise HTTPException(status_code=400, detail="Inactive user")
    return current_user

async def get_user_from_token(token: str, db: Session) -> User:
    """Get user from WebSocket token"""
    try:
        payload = jwt.decode(token, SECRET_KEY, algorithms=[ALGORITHM])
        user_id: str = payload.get("sub")
        if user_id is None:
            return None
        
        user = db.query(User).filter(User.id == int(user_id)).first()
        if user is None or not user.is_active:
            return None
        return user
    except JWTError:
        return None