from typing import Generator, Optional

from fastapi import Depends, HTTPException, status
from fastapi.security import OAuth2PasswordBearer
from jose import jwt, JWTError
from pydantic import ValidationError
from sqlalchemy.orm import Session

from app import models, schemas
from app.core import security
from app.core.config import settings
from app.db.session import get_db

oauth2_scheme = OAuth2PasswordBearer(tokenUrl=f"{settings.API_V1_STR}/auth/login")


def get_current_user(
    db: Session = Depends(get_db), token: str = Depends(oauth2_scheme)
) -> models.User:
    try:
        payload = jwt.decode(
            token, settings.SECRET_KEY, algorithms=[settings.ALGORITHM]
        )
        token_data = schemas.TokenPayload(**payload)
    except (JWTError, ValidationError):
        raise HTTPException(
            status_code=status.HTTP_403_FORBIDDEN,
            detail="Could not validate credentials",
        )
    user = db.query(models.User).filter(models.User.id == token_data.sub).first()
    if not user:
        raise HTTPException(status_code=404, detail="User not found")
    if not user.is_active:
        raise HTTPException(status_code=400, detail="Inactive user")
    return user


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


def get_current_active_admin(
    current_user: models.User = Depends(get_current_user),
) -> models.User:
    if not current_user.is_admin:
        raise HTTPException(
            status_code=status.HTTP_403_FORBIDDEN, detail="Not enough permissions"
        )
    return current_user