auth.py

from datetime import datetime, timedelta, timezone
from typing import Optional
from jose import JWTError, jwt
from passlib.context import CryptContext
from sqlalchemy.orm import Session
from models import User, Session as DBSession

SECRET_KEY = "ochen_dlinnyi_i_slozhnyi_sekretnyi_kod_andrey_zubrila"
ALGORITHM = "HS256"
ACCESS_TOKEN_EXPIRE_MINUTES = 30

pwd_context = CryptContext(schemes=["argon2"], deprecated="auto")

def verify_password(plain_password, hashed_password):
    return pwd_context.verify(plain_password, hashed_password)

def get_password_hash(password):
    return pwd_context.hash(password)

def get_user_by_login(db: Session, login: str) -> Optional[User]:
    return db.query(User).filter(User.login == login).first()

def authenticate_user(db: Session, login: str, password: str) -> Optional[User]:
    user = get_user_by_login(db, login)
    if not user:
        return None
    if not verify_password(password, user.password_hash):
        return None
    return user

def create_access_token(data: dict, expires_delta: Optional[timedelta] = None):
    to_encode = data.copy()
    if expires_delta:
        expire = datetime.now(timezone.utc) + expires_delta
    else:
        expire = datetime.now(timezone.utc) + timedelta(minutes=ACCESS_TOKEN_EXPIRE_MINUTES)
    to_encode.update({"exp": expire})
    encoded_jwt = jwt.encode(to_encode, SECRET_KEY, algorithm=ALGORITHM)
    return encoded_jwt

def get_current_user(token: str, db: Session) -> Optional[User]:
    try:
        payload = jwt.decode(token, SECRET_KEY, algorithms=[ALGORITHM])
        login: str = payload.get("sub")
        if login is None:
            return None
    except JWTError:
        return None
    
    user = get_user_by_login(db, login)
    return user