from datetime import datetime, timedelta
from typing import Any, Union, Optional

from jose import jwt
from passlib.context import CryptContext
from app.core.config import settings

# 密码上下文
pwd_context = CryptContext(schemes=["bcrypt"], deprecated="auto")

# 创建访问令牌
def create_access_token(
    subject: Union[str, Any], expires_delta: Optional[timedelta] = None
) -> str:
    if expires_delta:
        expire = datetime.now() + expires_delta
    else:
        expire = datetime.now() + timedelta(
            minutes=settings.ACCESS_TOKEN_EXPIRE_MINUTES
        )
    to_encode = {"exp": expire, "sub": str(subject)}
    encoded_jwt = jwt.encode(to_encode, settings.SECRET_KEY, algorithm=settings.ALGORITHM)
    return encoded_jwt

# 验证令牌
def verify_token(token: str) -> Optional[str]:
    try:
        payload = jwt.decode(
            token, settings.SECRET_KEY, algorithms=[settings.ALGORITHM]
        )
        return payload.get("sub")
    except jwt.JWTError:
        return None