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

from jose import JWTError, jwt

SECRET_KEY = os.getenv("KEFU_SECRET_KEY", "kefu-dev-secret-change-in-production")
ALGORITHM = "HS256"
ACCESS_TOKEN_EXPIRE_MINUTES = int(os.getenv("KEFU_TOKEN_EXPIRE_MINUTES", str(60 * 24)))


def create_access_token(subject: str, extra: Optional[dict[str, Any]] = None) -> str:
    expire = datetime.utcnow() + timedelta(minutes=ACCESS_TOKEN_EXPIRE_MINUTES)
    payload = {"sub": subject, "exp": expire}
    if extra:
        payload.update(extra)
    return jwt.encode(payload, SECRET_KEY, algorithm=ALGORITHM)


def decode_access_token(token: str) -> Optional[dict[str, Any]]:
    try:
        return jwt.decode(token, SECRET_KEY, algorithms=[ALGORITHM])
    except JWTError:
        return None